Attachment structure for attachable body and image forming apparatus

An attachment structure for an attachable body includes an attachable body, a connecting unit, a first regulating device, and a second regulating device. The attachable body is attachable to an apparatus body and has a leading end and a trailing end in an attachment direction in which the attachable body is attached to the apparatus body. The connecting unit is provided on a leading end side of the attachable body in the attachment direction. The connecting unit is connected to the apparatus body. The first regulating device regulates a movement of the attachable body in the attachment direction from a trailing end side. The second regulating device is provided at a position closer to the connecting unit than to the first regulating device in a perpendicular direction perpendicular to the attachment direction. The second regulating device regulates the movement of the attachable body.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2016-168358 filed Aug. 30, 2016.

BACKGROUND

Technical Field

The present invention relates to an attachment structure for an attachable body and an image forming apparatus.

SUMMARY

According to an aspect of the present invention, an attachment structure for an attachable body includes an attachable body, a connecting unit, a first regulating device, and a second regulating device. The attachable body is attachable to an apparatus body and has a leading end and a trailing end in an attachment direction in which the attachable body is attached to the apparatus body. The connecting unit is provided on a leading end side of the attachable body in the attachment direction. The connecting unit is connected to the apparatus body. The first regulating device regulates a movement of the attachable body in the attachment direction from a trailing end side. The second regulating device is provided at a position closer to the connecting unit than to the first regulating device in a perpendicular direction perpendicular to the attachment direction. The second regulating device regulates the movement of the attachable body.

DETAILED DESCRIPTION

An Overall Structure of an Image Forming Apparatus

As illustrated inFIG. 1, an image forming apparatus10according to an exemplary embodiment includes a transport section12, an image forming section14, a fixing device30, and a controller20. The transport section12includes a transport roller pair13that transports sheets P. The image forming section14forms toner images G with toner T on the sheets P transported by the transport section12. The fixing device30heats the toner images G so as to fix the toner images G onto the sheets P. Here, the fixing device30is an example of an attachable body.

The image forming section14performs charging, light exposure, developing, and transfer steps which are steps in a known electrophotographic method. Furthermore, the controller20controls components of the image forming apparatus10other than the controller20.

It is noted that, in the following description, when the image forming apparatus10is seen from the front as illustrated inFIG. 1, the apparatus height direction, the apparatus width direction, and the apparatus depth direction are respectively referred to as the Y direction, the X direction, and the Z direction. Furthermore, in the case where it is required to distinguish between one side and another side in the X direction, the Y direction, and the Z direction, the upper side is the Y side, the lower side is the −Y side, the right side is the X side, the left side is the −X side, the rear side is the Z side, and the front side is the −Z side when the image forming apparatus10is seen from the front.

Image Forming Operation

Next, an image forming operation according to the present exemplary embodiment is described with reference toFIG. 1.

Upon reception of image data from an external device (not illustrated), the controller20causes the components of the image forming apparatus10other than the controller20to operate. Specifically, the controller20causes the transport section12to transport the sheets P, causes the image forming section14to form the toner images G, and causes the fixing device30to fix the toner images G on the sheets P. The sheets P onto which the toner images G have been fixed are output to the outside of the image forming apparatus10. Thus, the image forming operation has been performed.

Configurations of Parts

Next, configurations of parts of an attachment structure according to the present exemplary embodiment are described with reference to the drawings. Here,FIG. 2is a perspective view of a firmly securing device100and a temporarily securing device300of the image forming apparatus10.FIGS. 3A and 3Billustrate operation of the firmly securing device100, respectively illustrating a released state and a secured state.FIG. 4is an external perspective view of the fixing device30.FIG. 5is a side view of the fixing device30.FIG. 6is a plan view of a part where the fixing device30is attached to an apparatus body10A.FIG. 7is a side sectional view (sectional view taken along line VII-VII ofFIG. 6) of the part where the fixing device30is attached to the apparatus body10A.FIG. 8is a side sectional view (sectional view taken along line VIII-VIII ofFIG. 6) of the part where the fixing device30is attached to the apparatus body10A.FIG. 9is a side sectional view (sectional view taken along line IX-IX ofFIG. 6) of the part where the fixing device30is attached to the apparatus body10A.FIG. 10is a side sectional view (sectional view taken along line X-X ofFIG. 6) of the part where the fixing device30is attached to the apparatus body10A.

The Apparatus Body

The part where the fixing device30is attached to the apparatus body10A of the image forming apparatus10is described.

As illustrated inFIGS. 2 and 6, the apparatus body10A according to the present exemplary embodiment includes a frame130, the firmly securing device100, and an electromagnetic induction heater200. The frame130is a structural body of the apparatus body10A. The firmly securing device100is provided in the frame130and secures the fixing device30. The electromagnetic induction heater200heats a fixing belt32. The apparatus body10A also includes a terminal unit160, a gear train180, and a gear train170. The terminal unit160electrically connects the apparatus body10A and the fixing device30to each other. The gear train180rotates the fixing belt32and a pressure roller34. The gear train170is used for adjustment of a pressure state of a nip N.

The Frame

The frame130is the structural body of the apparatus body10A. The frame130is formed by combining metal plates. The fixing device30is secured to the frame130. Furthermore, components for operation of the fixing device30are disposed in the apparatus body10A.

The frame130is formed so as to have a step shape on the −Z side of the part where the fixing device30is attached. In more detail, a first structural surface130A, a second structural surface130B, and a third structural surface130C are provided. The first and second structural surfaces130A (Y-Z surface; seeFIGS. 7 and 8) and130B (Y-Z surface; seeFIG. 10) face a leading surface (surface on the −X side) of the fixing device30. The third structural surface130C (X-Z surface) faces a lower surface (surface on the −Y side; seeFIGS. 7 and 8) of the fixing device30. Furthermore, a fourth structural surface130D is provided. The fourth structural surface130D is a surface (Y-Z surface) that extends in the −Y direction from a trailing end (end portion on the X side) of the third structural surface130C (seeFIGS. 2, 7, and 8). Furthermore, as illustrated inFIGS. 2 and 6, a fifth structural surface130E and a sixth structural surface130F are provided. The fifth structural surface130E is a surface (X-Y surface) facing a side surface (surface on the −Z side) of the fixing device30. The sixth structural surface130F is a surface (Y-Z surface) that extends from a trailing end (end portion on the X side) of the fifth structural surface130E toward the −Z side. Although it is not particularly illustrated, structural surfaces included in the frame130are also provide at portions facing the leading surface (surface on the −X side) and a side surface (surface on the Z side) of the fixing device30on the Z side of the fixing device30.

A pinching portion133that pinches a leading end portion321of the fixing device30is provided at a leading end (end portion on the −X side) of the third structural surface130C (seeFIG. 8). The leading end portion321of the fixing device30will be described later. Specifically, the pinching portion133is formed by, as illustrated inFIG. 8, folding part of a metal plate of the first structural surface130A toward the Y side about a fold line extending in the X direction. The pinching portion133has a groove formed from an end portion on the X side toward an end portion on the −X side. This groove extends throughout the pinching portion133in the Z direction. The leading end portion321of a housing31of the fixing device30is inserted into the groove, thereby a movement of the fixing device30in the Y direction is regulated.

A securing hole132through which a projection320on the −Z side of the fixing device30, which will be described later, is inserted is provided on the −Z side of the fourth structural surface130D (seeFIGS. 7 and 8). When the projection320is inserted into the securing hole132, the movement of the fixing device30in the Y direction is regulated. Also, another securing hole132is provided on a structural surface (Y-Z surface) on the Z side. When another projection320of the fixing device30on the Z side is inserted into the securing hole132on the Z side, the movement of the fixing device30in the Y direction is regulated.

Furthermore, as illustrated inFIGS. 2 and 7, a standing portion120that stands on the X side is provided at an end portion on the −Z side of the fourth structural surface130D. The standing portion120is a plate-shaped member having an X-Y surface and has a securing hole121through which a columnar projection304of the temporarily securing device300, which will be described later, is inserted. The securing hole121is an elongated hole elongated in the Y direction. The width of the securing hole121in the X direction is substantially equal to an outer diameter of the columnar projection304. More specifically, the length of the securing hole121in the X direction may vary the outer diameter of the columnar projection304within a tolerance. Furthermore, the length of the securing hole121in the Y direction is about 1.2 to 1.5 times the outer diameter of the columnar projection304. Furthermore, an inclination122is provided so as to extend from an end portion of the standing portion120on the X side toward the X side. The inclination122is a surface inclined from the standing portion120toward the outside (−Z side) of the apparatus body10A. It is noted that another standing portion120, another securing hole121, and another inclination122are provided on a structural surface (Y-Z surface) on the Z side. These elements on the Z side and −Z side are systematically arranged.

The Firmly Securing Device

As illustrated inFIG. 2, the firmly securing device100for securing the fixing device30is provided at a position which is an end portion on the Z side of the sixth structural surface130F and which corresponds to a substantial center of the fixing device30in the Y direction. The firmly securing device100includes a support103, a movable shaft102, an operating portion101, and a stopper104. The support103is provided on the sixth structural surface130F. The movable shaft102is supported so as to be movable in the axial direction relative to the support103. The operating portion101is used to move the movable shaft102. The stopper104regulates rotation of the operating portion101. Here, the movable shaft102is an example of a shaft portion.

The support103is a plate-shaped member provided on the sixth structural surface130F. Both ends of the support103in the Z direction are bent toward the X side. More particularly, the support103includes a securing surface103A secured to the sixth structural surface130F and a pair of bent portions103B which are formed by bending both the ends in the Z direction of the securing surface103A. The support103supports the movable shaft102and the operating portion101.

As illustrated inFIGS. 3A and 3B, the movable shaft102is a pin having a D shape in section and inserted into holes provided in the bent portions103B. The length of the movable shaft102is larger than the distance between the pair of bent portions103B. Accordingly, the movable shaft102is movable in the Z direction and projects from the support103toward the Z side or is disposed within the support103. In the support103according to the present exemplary embodiment, one of the bent portions103B on the Z side is positioned at an end portion on the Z side of the sixth structural surface130F. Accordingly, the movable shaft102is able to project from the apparatus body10A toward the fixing device30. In the case where the movable shaft102projects toward the Z side, an outer circumferential surface of the movable shaft102faces a receiving portion310of the fixing device30, which will be described later. The movable shaft102is rotatable about the axis.

Here, as illustrated inFIGS. 2, 3A and 3B, the outer circumferential surface of the movable shaft102includes a cylindrical surface102A and a flat surface102B (an example of a surface) formed by cutting part of the cylindrical surface102A in the axial direction (Z direction). When the cylindrical surface102A faces the receiving portion310, the cylindrical surface102A is in contact with the receiving portion310so as to press the receiving portion310in the −X direction. In contrast, when the flat surface102B faces the receiving portion310, a gap of 1 mm is formed between the flat surface102B and the receiving portion310.

The operating portion101causes, when operated by an operator, the movable shaft102to move in the Z direction and rotate the movable shaft102about the axis in the Z direction. The operating portion101has a hole on the Y side thereof. The movable shaft102is fitted into this hole. As illustrated inFIG. 3A, when the operating portion101is moved upward (toward the Y side; this state is referred to as “released state” hereafter), the flat surface102B of the movable shaft102faces the receiving portion310. In contrast, as illustrated inFIG. 3B, when the operating portion101is moved downward (toward the −Y side; this state is referred to as “secured state” hereafter), the cylindrical surface102A of the movable shaft102faces the receiving portion310.

The stopper104is a plate-shaped projection formed on the surface on the Z side of the operating portion101. As illustrated inFIG. 3A, in the case where the operating portion101is operated so as to be set in the released state, when an end portion on the Y side of the stopper104is brought into contact with one of the bent portions103B, an upward (Y side) operation of the operating portion101is regulated. In contrast, as illustrated inFIG. 3B, in the case where the operating portion101is operated so as to be set in the secured state, when an end portion on the −Y side of the stopper104is brought into contact with the bent portion103B, a downward (−Y side) operation of the operating portion101is regulated.

The Electromagnetic Induction Heater

As illustrated inFIGS. 6 and 10, the electromagnetic induction heater200that heats the fixing belt32is provided on the second structural surface130B. The electromagnetic induction heater200includes a coil housing201and a support204. The coil housing201houses therein an exciting coil250that heats the fixing belt32through electromagnetic induction. The support204supports the coil housing201such that the coil housing201is movable in the attachment direction (X direction). The electromagnetic induction heater200also includes contacts202, screws205, and springs206. The contacts202are provided at both ends in the Z direction of the coil housing201. The screws205connect the contacts202to the second structural surface130B. The springs206press the coil housing201toward the fixing belt32side. Here, the electromagnetic induction heater200is an example of a pressing member.

As illustrated inFIG. 10, the coil housing201houses therein the exciting coil250to which an alternating current is applied. The surface on the X side of the coil housing201is a cylindrical recess following the shape of the fixing belt32.

The support204supports the coil housing201such that the coil housing201is movable in the attachment direction (X direction). The support204includes a base204A, a first grip204B, and a second grip204C. The base204A is provided along and screwed to the second structural surface130B. The first grip204B stands erect on the X side at an end portion on the −Y side of the base204A. The second grip204C stands erect on the X side at an end portion on the Y side of the base204A. Here, elongated holes204D elongated in the X direction are provided in the first grip204B and the second grip204C. Projections201A provided at both ends in the Y direction of the coil housing201are inserted into these elongated holes204D. Thus, the coil housing201is supported such that the coil housing201is fixed in the Y direction and the Z direction while being movable in the X direction that is the attachment direction of the fixing device30(seeFIG. 6).

The contacts202provided at both the ends in the Z direction of the coil housing201are projections of the coil housing201. The surface on the X side of the plate-shaped contacts202are in contact with the housing31of the fixing device30.

The screws205connect the contacts202to the second structural surface130B. Specifically, the heads of the screws205are inserted into holes provided in the contacts202and the shafts of the screws205are screwed to the second structural surface130B.

The springs206press the coil housing201toward the fixing device30. The springs206being coil springs are disposed around the shafts of the screws205. One end and the other end of each of the springs206are respectively in contact with a corresponding one of the contacts202and the second structural surface130B. With this configuration, the other end of the spring206is secured to the second structural surface130B and the one end in contact with the contact202presses the contact202(coil housing201) toward the X side.

The Terminal Unit

As illustrated inFIG. 8, the terminal unit160is provided in the first structural surface130A on the −Z side. The terminal unit160electrically connects the apparatus body10A and the fixing device30to each other. Specifically, a terminal unit62which will be described later is inserted into the terminal unit160. The details of the terminal will be described later.

The Gear Trains

The gear train180for rotation of the fixing belt32and the pressure roller34is provided in an opening existing between the first structural surface130A and the second structural surface130B (seeFIG. 9). The gear train180is rotated by a drive motor (not illustrated). One of the gears of the gear train180engaged with an operating gear80on the fixing device30side is referred to as a drive gear180A. The operating gear80will be described later.

The gear train170used for adjustment of the pressure state of the nip N, which will be described later, is provided on the fifth structural surface130E (seeFIG. 7). The gear train170is rotated by an operating motor (not illustrated). One of the gears of the gear train170engaged with an input gear70on the fixing device30side is referred to as an output gear170A. The input gear70will be described later.

The Fixing Device

The fixing device30according to the present exemplary embodiment includes the housing31, the fixing belt32, the pressure roller34, and the temporarily securing device300. The elements included in the fixing device30are described in the following.

FIG. 4is a perspective view of the fixing device30seen from the trailing side in the attachment direction (X direction). The fixing device30is attached to the apparatus body10A by being moved from the X side to the −X side and detached from the apparatus body10A by being moved from the −X side to the X side.

The Housing

As illustrated inFIG. 4, the housing31has a box shape the longitudinal direction of which extends in the Z direction. Openings that allow each of the sheets P to pass therethrough are provided on walls (not illustrated) on the Y side and the −Y side of the housing31.

Two handles350with which the fixing device30is operated during attachment and detachment of the fixing device30are provided on the trailing side (X side) of the housing31in the attachment direction (X direction). The handles350include a left handle350A on the −Z side and a right handle350B on the Z side.

The Temporarily Securing Device

As illustrated inFIG. 4, two temporarily securing devices300that secure the fixing device30to the apparatus body10A are provided at both ends on the −Y side of the housing31. Specifically, the fixing device30is secured by the standing portions120of the apparatus body10A and the temporarily securing devices300. The temporarily securing devices300include a left temporarily securing device300A provided on the −Z side and a right temporarily securing device300B provided on the Z side. Here, each of the temporarily securing devices300and a corresponding one of the standing portions120are included in an example of a first regulating device.

The left temporarily securing device300A is described below with reference toFIG. 4.

The temporarily securing devices300each include a support302, the projection304, a release portion301, and a spring303. The support302extends from the housing31toward the −Y side. The projection304is movably supported by the support302. The release portion301is for moving the projection304. The spring303applies pressure so that the projection304projects from the support302.

The support302is a plate-shaped member extended from an end portion on the −Y side of the housing31toward the −Y side and formed by bending toward the X side both the ends in the Z direction. Specifically, the support302includes an extension302A and a pair of bent portions302B. The extension302A is a portion extended from the end portion on the −Y side of the housing31and provided as a Y-Z surface. The pair of bent portions302B are portions formed by bending both the ends in the Z direction of the extension302A and provided as X-Y surfaces. The support302supports the projection304, the release portion301, and the spring303.

The projection304is a columnar pin inserted into holes formed in the bent portions302B. The length of the projection304is larger than the distance between the pair of bent portions302B. Accordingly, the projection304is movable in the Z direction and projects from the support302toward the Z side. The projection304is insertable into the securing hole121provided in the apparatus body10A.

The release portion301moves the projection304in the Z direction. The release portion301includes a pair of standing surfaces301A, a base301B, and an operating surface301C. The pair of standing surfaces301A are provided adjacent to the pair of bent portions302B. The base301B connects end portions on the −Y side of the pair of standing surfaces301A to each other. The operating surface301C extends from the base301B toward the −Y side and provided as an X-Y surface. The standing surfaces301A have holes into which the projection304is inserted. Here, when observing the left temporarily securing device300A from the X side, one of the standing surfaces301A, one of the bent portions302B, the other standing surface301A, and the other bent portion302B are arranged in this order from the Z side toward the −Z side. The end portion on the Z side of the projection304is secured to the standing surface301A and the end portion on the −Z side of the projection304projects from the bent portion302B.

The spring303is a coil spring provided between the bent portion302B on the Z side and the standing surface301A on the −Z side. The projection304as a pin is inserted through the spring303in the axial direction (Z direction). With this spring303, the projection304and the release portion301are pressed from the Z side toward the −Z side. Accordingly, as illustrated inFIG. 4, while the projection304and the release portion301are pressed by the spring303, the end portion on the −Z side of the projection304projects from the bent portions302B on the −Z side. In contrast, when the operating surface301C is operated so as to be moved toward the Z side against the pressing force of the spring303, the projection304is contained in the support302.

The structure of the right temporarily securing device300B is reversed with respect to that of the left temporarily securing device300A along the Z direction. That is, as illustrated inFIG. 4, while the projection304and the release portion301are pressed by the spring303, the end portion on the Z side of the projection304projects from the bent portions302B on the Z side. In contrast, when the operating surface301C is operated so as to be moved toward the −Z side against the pressing force of the spring303, the projection304is contained in the support302.

The Receiving Portion

The receiving portion310is a box-shaped member provided at a position which is the substantial center of the housing31in the Y direction and an end portion on the −Z side of the housing31. The receiving portion310is supported by a metal frame35of the housing31(seeFIG. 7). A side surface on the X side of the receiving portion310is able to be brought into contact with the movable shaft102of the firmly securing device100. Here, the firmly securing device100and the receiving portion310are included in an example of a second regulating device.

The Projection

As illustrated inFIG. 5, the projection320is a conical projection projected from the extension302A of the support302toward the −X side and provided in each of the left temporarily securing device300A and the right temporarily securing device300B. The projection320is fitted into the securing hole132provided at a position corresponding to the projection320when the fixing device30is attached to the apparatus body10A. When the projection320is fitted into the securing hole132, the movement of the housing31(fixing device30) in the Y direction is regulated. Here, the projection320and the securing hole132are included in an example of a third regulating device.

The Leading End Portion

As illustrated inFIG. 8, the leading end portion321is part of the frame35of the housing31and a leading end portion of a metal plate projecting toward the −X side. The leading end portion321is fitted into the pinching portion133provided at a position corresponding to the leading end portion321when the fixing device30is attached to the apparatus body10A. When the leading end portion321is fitted into the pinching portion133, the movement of the housing31(fixing device30) in the Y direction is regulated. Here, the leading end portion321and the pinching portion133are included in the example of the third regulating device.

Wiring Connecting Unit

A wiring connecting unit60is used to receive power required for operating the fixing device30and transmitting signals from sensors and the like included in the fixing device30. The wiring connecting unit60is movable in the X direction. Here, the wiring connecting unit60is an example of a connecting unit.

As illustrated inFIGS. 6 and 8, the wiring connecting unit60is a connector having a rectangular parallelepiped shape. The sides of the wiring connecting unit60in the X direction and the Y direction are long and the sides of the wiring connecting unit60in the Z direction are short. The wiring connecting unit60includes a body61, the terminal unit62, a leading-side flange63, and a trailing-side flange64. The terminal unit62is provided at an end portion on the −X side. The leading-side flange63is provided at the boundary between the terminal unit62and the body61. The trailing-side flange64is provided on the trailing side (X side) of the body61. The wiring connecting unit60also includes securing screws65and springs66. The securing screws65secure the trailing-side flange64and the frame35to each other. The springs66press the wiring connecting unit60toward the −X side.

A power cable and signal wires for the sensors are connected to the trailing side (X side) of the body61. These cables and signal wires are electrically connected to terminals (not illustrated) provided in the terminal unit62.

The terminal unit62is a connecting portion for connection to the terminal unit160provided on the apparatus body10A side. The terminal unit62is a male connector which is inserted into the terminal unit160which is a female connector so as to be connected to the terminal unit160.

The leading-side flange63is provided at the boundary between the terminal unit62and the body61. The leading-side flange63projects so as to surround the body61. The leading-side flange63is in contact with the end (end portion on the X side) of the terminal unit160when the terminal unit62is connected to the terminal unit160on the apparatus body10A side.

The trailing-side flange64is provided on the trailing side (X side) of the body61. The trailing-side flange64projects from both ends in the Y direction of the body61. The trailing-side flange64has holes (not illustrated) at both ends thereof in the Y direction. The securing screws65are inserted through the respective holes.

The securing screws65are inserted through the holes (not illustrated) of the trailing-side flange64. The ends of the securing screws65(end portions on the −X side) are secured to the frame35.

The securing screws65are inserted through the springs66in the axial direction (X direction). End portions on the X side of the springs66are in contact with the heads of the securing screws65and end portions on the −X side of the springs66are in contact with a trailing end surface (surface on the X side) of the trailing-side flange64. That is, the springs66press the wiring connecting unit60toward the leading side (−X side) in the attachment direction (X direction). When the fixing device30is not attached to the apparatus body10A, the trailing-side flange64is in contact with the frame35due to the pressing forces of the springs66. When the terminal unit62is connected to the terminal unit160of the apparatus body10A, the terminal unit160moves the wiring connecting unit60toward the X side against the pressing forces of the springs66. In other words, the springs66press the terminal unit62against the terminal unit160.

The Pressure Roller

The pressure roller34is disposed on the opposite side (X side) of a transport path L of the sheet P (seeFIG. 1) to the fixing belt32side so as to be rotatable about the axis. The axial direction of the pressure roller34extends in the Z direction. As an example according to the present exemplary embodiment, the transport direction of the sheet P extends in the Y direction in the fixing device30, and the width direction perpendicular to the transport direction of the sheet P extends in the Z direction.

Here, as illustrated inFIG. 9, the pressure roller34is rotated by motive power of the drive motor (not illustrated) of the apparatus body10A transmitted via the plural gears. Specifically, the drive force from the drive motor (not illustrated) of the apparatus body10A is transmitted to the gear train180, and then to the operating gear80of the fixing device30from the drive gear180A on the X side of the gear train180. The drive force is then transmitted from the operating gear80to the pressure roller34via a gear train81, thereby the pressure roller34is rotated. Here, the operating gear80is included in an example of an input device.

Here, a portion where the sheet P is nipped between an outer circumferential surface of the pressure roller34and an outer circumferential surface of the fixing belt32and where the toner T on the sheet P is subjected to heat and pressure is referred to as a nip N. As illustrated inFIG. 7, motive power of an operating motor (not illustrated) of the apparatus body10A is transmitted via the plural gears. This allows the pressure state in the nip N to be adjusted. Specifically, a drive force from the operating motor (not illustrated) of the apparatus body10A is transmitted to the gear train170, and then to the input gear70of the fixing device30from the output gear170A on the X side of the gear train170. Then, the drive force is transmitted from the input gear70to a cam72(seeFIG. 6) via a gear train71. When the cam72presses a lever (not illustrated) upward, the pressure roller34is separated from the fixing belt32, thereby a pressure state (nip state) is released. Here, the input gear70is included in the example of the input device.

The Fixing Belt

The fixing belt32is an endless belt and disposed on the toner image G side (−X side) of the transport path L of the sheet P (seeFIG. 1) so as to be rotatable about the axis. The axial direction of the fixing belt32extends in the Z direction. Furthermore, the fixing belt32is supported without being tensioned so that portions of the fixing belt32other than both ends in the width direction and the nip N are not brought into contact with other members. Here, examples of the structure of the fixing belt32include, for example, a structure in which a metal heating layer that generates heat due to electromagnetic induction, an elastic layer, and a surface mold release layer are disposed in this order on a base material layer. With this structure, an alternating current magnetic field from the electromagnetic induction heater200passes through the metal heating layer in the width direction. This generates eddy currents in the metal heating layer, thereby the metal heating layer is heated. Thus, the fixing belt32generates heat.

A gear for a belt (not illustrated) is provided at an end portion on the −Z side of the fixing belt32. The motive force of the same drive motor (not illustrated) as that used for the pressure roller34is transmitted to the gear train81via plural gears to rotate the above-described gear for a belt.

As has been described, the fixing belt32according to the present exemplary embodiment is heated by the electromagnetic induction heater200and heats the sheet P and the toner images G (toner T) formed on the sheet P while being rotated. Thus, the toner images G are fixed onto the sheet P.

The surface temperature of the fixing belt32is measured by, for example, a thermo-sensitive element provided for the fixing belt32and controlled by a controller. The type of the thermo-sensitive element is not particularly limited. Examples of the thermo-sensitive element include, for example, a thermistor, a temperature sensor, and so forth.

Methods of Attachment and Detachment

Next, a method of attaching the fixing device30to the apparatus body10A according to the present exemplary embodiment is described. First, the operator opens a door (not illustrated) disposed on a side surface (surface on the X side) of the image forming apparatus10. Thus, the operator faces the apparatus body10A. Then, the operator performs operations in the following order.

(1) Temporarily Securing of the Fixing Device

First, when the operating portion101of the firmly securing device100is in the secured state, the operator sets the operating portion101in the released state and moves the operating portion101toward the −Z side so as to retract the movable shaft102toward the −Z side. Thus, the end portion on the Z side of the movable shaft102is positioned further to the −Z side than the fifth structural surface130E. Thus, the fixing device30becomes ready to be inserted.

Next, the operator holds two handles350of the fixing device30and inserts the fixing device30toward an attachment part of the apparatus body10A in the attachment direction (−X side). At this time, the terminal unit62of the fixing device30is inserted into the terminal unit160of the apparatus body10A. When the terminal unit160is brought into contact with the leading-side flange63, the terminal unit160of the apparatus body10A moves the wiring connecting unit60toward the X side against the pressing forces of the springs66of the wiring connecting unit60. Furthermore, when the housing31is brought into contact with the contacts202of the electromagnetic induction heater200, the housing31moves the coil housing201toward the −X side against the pressing forces of the springs206of the electromagnetic induction heater200.

Meanwhile, the projections304of the temporarily securing devices300on both the ends in the Z direction are each brought into contact with a corresponding one of the inclinations122of the apparatus body10A. When the operator moves the fixing device30further toward the −X side, the projections304are contained in the supports302due to the inclinations122against the pressing forces of the springs303. When the projection304reach the securing holes121, the ends of the projections304are inserted into the securing holes121due to the pressing forces of the springs303. This sets the fixing device30in a temporarily secured state in which the movement of the fixing device30in the X direction is regulated. Furthermore, when the projections320of the fixing device30are fitted into the securing holes132of the apparatus body10A, the leading end portion321of the fixing device30is pinched by the pinching portion133of the apparatus body10A. This regulates the movement of the housing31(fixing device30) in the Y direction (seeFIG. 8).

As has been described, in order to attach the fixing device30to the attachment part of the apparatus body10A, the operator needs to insert the fixing device30into the apparatus body10A against the pressing forces of the springs66of the wiring connecting unit60, the springs206of the electromagnetic induction heater200, and the springs303of the temporarily securing devices300.

(2) Firmly Securing the Fixing Device

In the temporarily secured state, the operator moves the operating portion101of the firmly securing device100toward the Z side so as to cause the movable shaft102to project toward the Z side. As a result, the projecting portion of the movable shaft102faces the receiving portion310. During this movement of the operating portion101toward the Z side, the flat surface102B of the movable shaft102is positioned at the facing portion that faces the receiving portion310because of the operating portion101being in the released state. That is, since the 1 mm gap exists between the movable shaft102and the receiving portion310as has been described, the movable shaft102is moved toward the Z side without being brought into contact with the receiving portion310.

Then, the operator sets the operating portion101in the secured state. At this time, the cylindrical surface102A of the movable shaft102is pressed against the receiving portion310. This sets the fixing device30in the firmly secured state in which the movement of the fixing device30in the X direction and the Y direction is regulated.

Next, a method of detaching the fixing device30from the apparatus body10A according to the present exemplary embodiment is described. As is the case with the attachment, the operator opens the door (not illustrated) of the image forming apparatus10. Thus, the operator faces the apparatus body10A. Then, the operator performs detachment in the following order.

(3) Releasing the Securing of the Fixing Device

First, during the firmly secured state, the operator sets the operating portion101of the firmly securing device100into the released state. As a result, the movable shaft102is rotated and the portion of the movable shaft102facing the receiving portion310transitions from the cylindrical surface102A to the flat surface102B. This changes the state from the firmly secured state to the temporally secured state.

Since the operating portion101is set in the released state, the 1 mm gap is formed between the movable shaft102and the receiving portion310. Thus, the operator is able to move the operating portion101toward the −Z side. Due to the movement of the operating portion101toward the −Z side, the end portion on the Z side of the movable shaft102is positioned further to the −Z side than the fifth structural surface130E. Thus, the fixing device30becomes ready to be detached.

(4) Detachment of the Fixing Device

Next, during the temporarily secured state, the operator operates the temporarily securing devices300so as to release the temporarily secured state in which the fixing device30is temporarily secured to the apparatus body10A. Specifically, the operator operates the release portion301on the −Z side to move toward the Z side and the release portion301on the Z side to move toward the −Z side, thereby containing the projections304received in the securing holes121in the supports302. This allows the fixing device30to move in the X direction. Then, the fixing device30is detached from the apparatus body10A.

Fixing Operation

Next, fixing operation of the fixing device30according to the present exemplary embodiment is described. In the fixing operation according to the present exemplary embodiment, the controller20controls the electromagnetic induction heater200to heat the fixing belt32and rotate the fixing belt32. With the fixing device30according to the present exemplary embodiment, the cam72is controlled so as to set a nipped state in accordance with the type of the sheet P used for the image forming operation. Furthermore, when the image forming apparatus10is in a stand-by state, in the event of a paper jam or the like, the cam72is controlled so as to set a nip released state. Switching between the nipped state and the nip released state (control of the cam72) is performed before the transport section12transports the sheet P, for example, as follows: a user inputs the type or the like of the sheet P used for the image forming operation to an input unit (not illustrated); and the controller20to which data relating to the type or the like of the sheet P is transmitted as a result of the input by the user switches the state between the nipped state and the nip released state. Then, the toner images G are formed by the image forming section14and fixed in the nip N onto the sheet P transported by the transport section12. Thus, the fixing operation is completed.

Operations

Next, operations according to the present exemplary embodiment are described on the basis of a comparative example and arrangement of the firmly securing device100and the temporarily securing devices300.

A Comparative Example

First, thumbscrews are used to secure the fixing device30for a related-art image forming apparatus as the comparative example. Specifically, according to the comparative example, the firmly securing device100is not provided. The fixing device30is secured by screwing the thumbscrews provided at the positions of the temporarily securing devices300according to the present exemplary embodiment into the apparatus body10A.

As has been described, in order to attach the fixing device30to the apparatus body10A, the operator needs to insert the fixing device30into the apparatus body10A against the pressing forces of the springs66of the wiring connecting unit60and the springs206of the electromagnetic induction heater200. With a method of securing according to the comparative example, after the fixing device30has been inserted toward the apparatus body10A, the operator needs to operate the thumbscrews by one of his or her hands while pressing the fixing device30against the apparatus body10A by the other hand. That is, during the securing work, the operator needs to use both of his or her hands. Furthermore, the operator needs to continue to firmly press the fixing device30until the thumbscrews are engaged with the apparatus body10A. That is, the operator needs to continue to press the fixing device30with an unnecessary force.

Arrangement of the Firmly Securing Device and the Temporarily Securing Devices

According to the exemplary embodiment of the invention, the temporarily securing devices300that use a pin insertion method instead of the thumbscrews are used, and in addition, the firmly securing device100is provided at the one end (on the −Z side) in the Z direction. Here, the arrangement of the firmly securing device100and the temporarily securing devices300is described.

As illustrated inFIG. 4, the temporarily securing devices300are provided at end portions on the −Y side at both the ends of the housing31in the Z direction. In contrast, the firmly securing device100is provided on the −Z side of the housing31. This −Z side is a portion where the wiring connecting unit60, a drive system for the fixing belt32and the pressure roller34(simply referred to as “drive system” hereafter), and an operating system that switches the nipped state (simply referred to as “operating system” hereafter) are provided. That is, the −Z side where the firmly securing device100and the left temporarily securing device300A are provided is subjected to the pressing forces of the springs and the drive forces of the gears.

As illustrated inFIG. 6, when the part of the fixing device30is attached is seen from the top, the input gear70that is the input device of the motive power for the operating system from the apparatus body10A to the fixing device30is provided between the firmly securing device100and the left temporarily securing device300A (between line VII-VII and line VIII-VIII) in the Z direction.

Furthermore, as illustrated inFIG. 7, when observing the section taken along line VII-VII, the input gear70that is the input device of the motive power for the operating system from the apparatus body10A to the fixing device30is provided between the firmly securing device100and the left temporarily securing device300A (between line E-E and line F-F) in the Y direction. More specifically, a contact position where the input gear70on which the motive power acts is in contact with the output gear170A is disposed closer to the firmly securing device100(line E-E) than to the left temporarily securing device300A (line F-F) in the Y direction.

Furthermore, as illustrated inFIG. 8, when observing the section taken along line VIII-VIII, the springs66are provided at both the ends in the Y direction so as to press the wiring connecting unit60against the terminal unit160of the apparatus body10A. A resultant force of the pressing forces of the springs66at both the ends is produced at a central portion in the Y direction of the wiring connecting unit60(in line H-H). Here, the central portion in the Y direction of the wiring connecting unit60(in line H-H) where the resultant force of the pressing forces of the springs66is produced is provided between the firmly securing device100and the left temporarily securing device300A (between line E-E and line F-F) in the Y direction. More specifically, the central portion in the Y direction of the wiring connecting unit60(in line H-H) where the resultant force of the pressing forces of the springs66is produced is provided closer to the firmly securing device100(line E-E) than to the left temporarily securing device300A (line F-F) in the Y direction.

Furthermore, as illustrated inFIG. 9, when observing the section taken along line IX-IX, the operating gear80that is the input device of the motive power for the driving system from the apparatus body10A to the fixing device30is provided between the firmly securing device100and the left temporarily securing device300A (between line E-E and line F-F) in the Y direction. More specifically, a contact position where the operating gear80on which the motive power acts is in contact with the drive gear180A is disposed closer to the firmly securing device100(line E-E) than to the left temporarily securing device300A (line F-F) in the Y direction.

Furthermore, as illustrated inFIG. 10, when observing the section taken along line X-X, the springs206that press the coil housing201of the electromagnetic induction heater200toward the fixing belt32side are provided between the firmly securing device100and the left temporarily securing device300A (between line E-E and line F-F) in the Y direction. More specifically, the springs206are provided closer to the firmly securing device100(line E-E) than to the left temporarily securing device300A (line F-F) in the Y direction. The position of the springs206in the Y direction is coincident with the position of the central portion in the Y direction of the wiring connecting unit60(in line H-H).

Furthermore, the nip N formed by the fixing belt32and the pressure roller34is provided between the firmly securing device100and the left temporarily securing device300A (between line E-E and line F-F) in the Y direction. More specifically, the nip N is provided closer to the firmly securing device100(line E-E) than to the left temporarily securing device300A (line F-F) in the Y direction.

The Details of the Operations

The detailed operations according to the present exemplary embodiment on the basis of the comparative example and the arrangement of the firmly securing device100and the temporarily securing devices300described above are as follows.

(1) The Temporarily Securing Devices and the Firmly Securing Device

The wiring connecting unit60is provided in the fixing device30to receive the power required to operate the fixing device30and transmit the signals from the sensors and the like included in the fixing device30. In order to electrically connect an attachable/detachable unit such as a fixing device30according to the present exemplary embodiment, a drawer connector, with which versatility of the angle for terminal connection is obtained, is used. In order to reliably connect the terminals, the springs66are provided at both the upper and lower (Y direction) ends of the wiring connecting unit60as the drawer connector, thereby the terminal unit62on the wiring connecting unit60side is pressed against the terminal unit160on the apparatus body10A side. As the pressing forces of the springs66increase, the connection between the terminal unit160and the terminal unit62becomes reliable. This produces, however, a resisting force when the fixing device30is inserted into the apparatus body10A.

In order to address this, the temporarily securing devices300and the firmly securing device100are provided according to the present exemplary embodiment. That is, when the temporarily securing devices300are attached to the apparatus body10A (in the case of temporary securing), the operator presses the temporarily securing device300side against the apparatus body10A so that the fixing device30is slightly inclined toward the temporarily securing device300side (the upper end side (Y side) of the fixing device30is inclined toward the X side) to attach the temporarily securing devices300to the apparatus body10A. Thus, out of the springs66disposed at both the upper and lower (Y direction) ends of the wiring connecting unit60, the lower (−Y side) spring66is compressed due to pressing of the temporarily securing device300side. Unlike the temporarily securing device300side, in the case of temporary securing, the pressing is small on the firmly securing device100side. Thus, the upper (Y side) spring66is compressed less than the lower (−Y side) spring66.

As has been described, according to the present exemplary embodiment, the springs66disposed at both the upper and lower (−Y direction) ends of the wiring connecting unit60are not simultaneously compressed during the temporary securing. This reduces a compressive force acting when the fixing device30is inserted. That is, compared to the case such as a case with the comparative example where an unnecessary force is applied for securing, an operating force may be reduced. Furthermore, according to the present exemplary embodiment, the fixing device30is secured only by pressing the fixing device30against the apparatus body10A. Thus, the operator may perform the attachment work only with one of his or her hands.

Furthermore, in the case of the firm securing, the cylindrical surface102A of the movable shaft102is pressed against the receiving portion310only by moving the operating portion101of the firmly securing device100downward. That is, the fixing device30is secured against the pressing forces of the springs66(the upper (Y side) spring66in particular).

(2) Disposition of the Points of Application Between the Firmly Securing Device and the Temporarily Securing Devices

As has been described, according to the present exemplary embodiment, the points of application of connecting portions between the fixing device30and the apparatus body10A are positioned between the firmly securing device100and the left temporarily securing device300A (between line E-E and line F-F) in the Y direction. Specifically, these points of application are as listed below.

Point of Application A: the position where the resultant force of the pressing forces of the springs66of the wiring connecting unit60is produced

Points of Application B: the positions where the pressing forces of the springs206of the electromagnetic induction heater200are produced

Point of Application C: the contact position where the input gear70that is the input device of the motive force for the operating system is in contact with the output gear170A

Point of Application D: the contact position where the operating gear80that is the input device of the motive force for the drive system is in contact with the drive gear180A.

Here, the fixing device30according to the present exemplary embodiment includes the frame35formed of metal. When the fixing device30is secured only with the temporarily securing devices300, the upper side (Y side) of the fixing device30is moved slightly toward the trailing side (X side) due to flexure of the frame35. Here, the lower side (−Y side) of the fixing device30is secured to the apparatus body10A. Accordingly, moments that rotate (clockwise inFIGS. 7 to 10) the upper side (Y side) toward the trailing side (X side) are produced in the fixing device30. This causes the fixing device30to be inclined toward the trailing side (X side).

According to the present exemplary embodiment, the firmly securing device100and the left temporarily securing device300A are disposed so that the above-described points of application where the moments that rotate the upper side (Y side) of the fixing device30toward the trailing side (X side) are produced are positioned between the firmly securing device100and the left temporarily securing device300A (between line E-E and line F-F). This may prevent the fixing device30from being inclined toward the trailing side (X side). Furthermore, in the case where the fixing device30is attached to the apparatus body10A, when the fixing device30is not inclined, neither the positional relationship between the axis of the input gear70and the axis of the output gear170A nor the positional relationship between the axis of the operating gear80and the axis of the drive gear180A is necessarily changed. In this case, tooth skipping between the input gear70and the output gear170A and between the operating gear80and the drive gear180A may be prevented.

Furthermore, as has been described, according to the present exemplary embodiment, the point of application C is positioned between the firmly securing device100and the left temporarily securing device300A (between line VII-VII and line VIII-VIII) in the Z direction (seeFIG. 6). Here, the temporarily securing devices300of the fixing device30according to the present exemplary embodiment are secured to the apparatus body10A, and the point of application C is positioned further to the −Z side than the left temporarily securing device300A. Accordingly, when the fixing device30is secured only with the temporarily securing devices300, the −Z side of the fixing device30is moved slightly toward the trailing side (X side) due to flexure of the frame35. That is, a moment that rotates (counterclockwise inFIG. 6) the end portion on the left side (−Z side) toward the trailing side (X side) is produced in the fixing device30. This causes the fixing device30to be inclined toward the trailing side (X side).

According to the present exemplary embodiment, the firmly securing device100and the left temporarily securing device300A are disposed so that the point of application C where the moment that rotates the end portion on the left side (−Z side) of the fixing device30toward the trailing side (X side) is produced is positioned between the firmly securing device100and the left temporarily securing device300A (between line VII-VII and line VIII-VIII). This may prevent the end portion on the left side (−Z side) of the fixing device30from being inclined toward the trailing side (X side). Furthermore, in the case where the fixing device30is attached to the apparatus body10A, when the fixing device30is not inclined, the positional relationship between the axis of the input gear70and the axis of the output gear170A is not necessarily changed. In this case, tooth skipping between the input gear70and the output gear170A may be prevented.

In the above description, the arrangement of the firmly securing device100and the left temporarily securing device300A with respect to the points of application has been discussed. However, the fixing device30and the apparatus body10A may be designed so that a resultant force of the forces applied to the points of application (points of application A to D) applied to a position between the firmly securing device100and the left temporarily securing device300A. In this case, however, a force is applied to the point of application C only when the nipped state is switched to the nip released state or the nip released state is switched to the nipped state. Accordingly, the fixing device30and the apparatus body10A may be designed so that a resultant force of the forces applied to the point of application A, the points of application B, and the point of application D is applied to a position between the firmly securing device100and the left temporarily securing device300A.

(3) Disposition of the Points of Application Near a Line Passing Through the Firmly Securing Device

As has been described, the temporarily securing devices300are secured by inserting the projections304into the securing holes121provided in the apparatus body10A. Here, although the width of the securing holes121in the X direction is substantially equal to the outer diameter of the projections304, there is the tolerance. Furthermore, the length of the securing holes121in the Y direction is about 1.2 to 1.5 times the outer diameter of the projections304(seeFIG. 7). Accordingly, when considering deformation of the frame35, positional accuracy of the temporarily securing devices300in the X direction is lower than that of the firmly securing device100that is secured by pressing the cylindrical surface102A of the movable shaft102.

According to the present exemplary embodiment, when the fixing device30is attached to the apparatus body10A, the positions of the points of application are closer to the firmly securing device100(line E-E) than to the left temporarily securing device300A (line F-F) in the Y direction. Thus, when the fixing device30is attached to the apparatus body10A, displacement of the fixing device30in the X direction may be suppressed. In this case, changes in the positional relationship between the axis of the input gear70and the axis of the output gear170A and the positional relationship between the axis of the operating gear80and the axis of the drive gear180A may be suppressed. That is, tooth skipping between the gears that connect the fixing device30and the apparatus body10A may be prevented.

Other than the above-described points of application A to D produced at the connecting portions between the fixing device30and the apparatus body10A, the following point of application exists in the fixing device30.

Point of Application E: the position where the pressing force of the nip N formed between the fixing belt32and the pressure roller34is produced.

Although the point of application E does not affect the positioning of the fixing device30, the point of application E relates to the deformation of the frame35. According to the present exemplary embodiment, the point of application E is disposed close to the firmly securing device100(line E-E). Thus, the firmly securing device100may suppress the deformation of the frame35. In this case, displacement of the fixing belt32and the pressure roller34in the X direction may be suppressed.

When the fixing device30is attached to the apparatus body10A, the positions of the points of application may be closer to the firmly securing device100(line VII-VII) than to the left temporarily securing device300A (line VIII-VIII) also in the Z direction. In this case, when the fixing device30is attached to the apparatus body10A, displacement of the fixing device30in the X direction may be suppressed.

As has been described, the positions of the points of application are closer to the firmly securing device100(line E-E, line VII-VII) than to the left temporarily securing device300A (line F-F, line VIII-VIII). That is, changes in the positional relationship between the axis of the input gear70and the axis of the output gear170A may be suppressed, changes in the positional relationship between the axis of the operating gear80and the axis of the drive gear180A may be suppressed, and displacement of the fixing belt32and the pressure roller34in the X direction may be suppressed. As the distance between any one of the points of application and the firmly securing device100reduces, the degree of suppression increases. That is, the points of application may be disposed on lines (line E-E, line VII-VII) passing through the firmly securing device100.

Similarly to the case where the point of application is positioned between the firmly securing device100and the left temporarily securing device300A, the arrangement of the firmly securing device100and the left temporarily securing device300A may be designed so that the resultant force of the forces applied to the points of application (points of application A to D) is applied to a position closer to the firmly securing device100(line E-E, line VII-VII) than to the left temporarily securing device300A (line F-F, line VIII-VIII). Also in this case, a force is applied to the point of application C only when the nipped state is switched to the nip released state or the nip released state is switched to the nipped state. Accordingly, the fixing device30and the apparatus body10A may be designed so that a resultant force of the forces applied to the point of application A, the points of application B, and the point of application D is applied to a position closer to the firmly securing device100(line E-E, line VII-VII) than to the left temporarily securing device300A (line F-F, line VIII-VIII).

(4) The Third Regulating Device

According to the exemplary embodiment of the invention, the example of the third regulating device that regulates the fixing device30in the vertical direction (Y direction) includes the projections320, the securing holes132, the leading end portion321, and the pinching portion133. When the projections320of the fixing device30are inserted into the securing holes132of the apparatus body10A and the leading end portion321of the fixing device30is pinched by the pinching portion133of the apparatus body10A, the movement of the fixing device30in the Y direction is regulated. In addition, the movement in the X direction is regulated by the temporarily securing devices300and the firmly securing device100. Thus, according to the present exemplary embodiment, the position of the fixing device30relative to the apparatus body10A is determined. It is noted that, according to the present exemplary embodiment, no external force acts in the Z direction. Accordingly, the degree of accuracy required in the X direction and the Y direction is not necessarily required for positional accuracy in the Z direction.

(5) The Flat Surface and the Cylindrical Surface of the Movable Shaft of the Firmly Securing Device

According to the present exemplary embodiment, the movable shaft102of the firmly securing device100has the cylindrical surface102A and the flat surface102B. The movable shaft102is moved in the axial direction (Z direction). More specifically, the movable shaft102is able to project from or retract into the support103. In the case where the operating portion101is operated so as to be set in the secured state, the cylindrical surface102A is brought into contact with the receiving portion310. In the case where the operating portion101is operated so as to be set in the released state, the gap is formed between the flat surface102B and the receiving portion310.

According to the present exemplary embodiment, in the case where the fixing device30is temporarily secured to the apparatus body10A, the flat surface102B and the fixing device30(receiving portion310) are not in contact with each other. Thus, the movable shaft102is able to be operated so as to move in the axial direction (Z direction) for the securing by using the firmly securing device100. Here, in order for the operator to move the movable shaft102in the axial direction (Z direction), such a large operating force that is required when pressing the fixing device30against the apparatus body10A is not required. Furthermore, in order to press the cylindrical surface102A against the receiving portion310, it is sufficient to operate the operating portion101so as to be set in the secured state. Accordingly, such a large operating force that is required when pressing the fixing device30against the apparatus body10A is not required. It is noted that, as the length of the operating portion101increases, the operating force for the firm securing of the fixing device30reduces. Also, as the outer diameter of the movable shaft102increases, the pressing force with which the fixing device30is pressed using the firmly securing device100during the firm securing increases.

As has been described, the operator may perform the firm securing with one of his or her hands.

Supplemental Remarks

Although the firmly securing device100is provided only on one side in the longitudinal direction (Z direction) of the fixing device30according to the present exemplary embodiment, this is not limiting. The firmly securing device100may be provided on each side in the longitudinal direction of the fixing device30. Furthermore, although the projecting directions of the projections304of the temporarily securing devices300and the movable shaft102of the firmly securing device100extend in the Z direction according to the present exemplary embodiment, this is not limiting. For example, the projections304and the movable shaft102may project in the Y direction as long as the fixing device30is able to be secured to the apparatus body10A.

Although the firmly securing device100and the standing portions120are provided in the apparatus body10A and the corresponding receiving portion310and the temporarily securing devices300are provided in the fixing device30according to the present exemplary embodiment, this is not limiting. For example, in some cases, the firmly securing device100and the temporarily securing devices300are provided in the apparatus body10A and the corresponding receiving portion310and the standing portions120are provided in the fixing device30. Alternatively, for example, in some cases, the receiving portion310and the standing portions120are provided in the apparatus body10A and the corresponding firmly securing device100and the temporarily securing devices300are provided in the fixing device30. Alternatively, for example, in some case, the temporarily securing devices300and the receiving portion310are provided in the apparatus body10A and the corresponding standing portions120and the firmly securing device100are provided in the fixing device30.

Although the movable shaft102according to the present exemplary embodiment has the flat surface102B, this is not limiting. The movable shaft102may have a curved surface or an uneven surface instead of the flat surface102B as long as the movable shaft102is able to be operated in the axial direction (Z direction). Furthermore, although the movable shaft102according to the present exemplary embodiment is a pin having a D shape in section, this is not limiting. The movable shaft102may instead be a cam in which the distance between the axis to an outer circumferential surface varies.

The exemplary embodiment of the invention is applicable not only to the fixing device30but also to a unit which is attached to the apparatus body10A and positioned by using a spring or the like during attachment or which is attached to the apparatus body10A and receives external motive power while the unit is movable. For example, the exemplary embodiment of the invention is applicable to a developing unit and a photosensitive unit.