Image forming device

Abstract

To achieve both the holding property and detachability of a detachable unit. [Solution] The image forming device 1 is provided with an image forming unit 10 that can be inserted into or removed from the device housing 2, a load supply member that applies a load to the image forming unit 10, and a load change section 36 that applies a climbing load Po to the image forming unit 10 via the lock lever 30 when the image forming unit 10 passes through the lock lever lock section 30b during insertion or removal of the image forming unit 10 from the device housing 2, applies a load Pw to the image forming unit 10 via the lock lever 30 when the image forming unit 10 is in a position attached to the device housing 2, and applies a load Ps that is greater than the load Pw to the image forming unit 10 via the lock lever 30 when restricting the range of movement of the image forming unit 10 after the image forming unit 10 has been attached to the device housing 2.

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus, and is suitable for application to image forming apparatuses such as copying machines and printers. [Background technology]

[0002] Conventionally, a widely used image forming apparatus is one in which an image is printed by irradiating the surface of a photosensitive drum in an image forming unit with light from a head unit having an exposure head that emits exposure light emitted from an LED (Light Emitting Diode) chip, which is a light emitting element, onto the surface of the photosensitive drum, thereby forming an electrostatic latent image on the surface of the photosensitive drum, and then by attaching a developer to the electrostatic latent image to develop a developer image, which is then transferred to a medium such as paper, and then the developer image is fixed to the medium by a fixing device.

[0003] Some image forming devices are configured so that the image forming unit can be attached to and detached from the image forming device (see, for example, Patent Document 1). In such image forming devices, when the image forming unit is attached to a predetermined attachment position in the image forming device and enters an attached state, the image forming unit is locked to prevent movement. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-31749 Summary of the Invention [Problem to be solved by the invention]

[0005] In such an image forming device, it is desirable to ensure that the image forming unit is held in place so that it does not move when attached, while also ensuring ease of attachment and detachment when attaching and detaching the image forming unit, which is a detachable unit.

[0006] The present invention has been made in consideration of the above points, and aims to propose an image forming apparatus that can achieve both the ease of holding and the ease of attaching and detaching a detachable unit. [Means for solving the problem]

[0007] In order to solve this problem, the image forming apparatus of the present invention is provided with a detachable unit that can be inserted into or removed from the device main body, a load supply member that applies a load to the detachable unit, and a load change section that applies a first load to the detachable unit by the load supply member when the detachable unit passes a predetermined position during insertion or removal of the detachable unit from the device main body, applies a second load to the detachable unit by the load supply member when the detachable unit is at a position where it is attached to the device main body, and applies a third load greater than the second load to the detachable unit by the load supply member after the detachable unit is attached to the device main body.

[0008] In addition, the image forming apparatus of the present invention is provided with a detachable unit that can be inserted into or removed from the apparatus main body, a load supply member that applies a load to the detachable unit, and a load change section that applies a first load to the detachable unit by the load supply member when the detachable unit passes a predetermined position during insertion or removal of the detachable unit from the apparatus main body, applies a second load to the detachable unit by the load supply member when the detachable unit is attached to the apparatus main body, and applies a third load greater than the second load to the detachable unit by the load supply member when image formation is possible.

[0009] As a result, the present invention applies a large third load to the detachable unit when the detachable unit is attached, thereby firmly holding the detachable unit, and when the detachable unit is attached or detached, the load applied to the detachable unit is a second load that is smaller than the third load, allowing the detachable unit to be easily attached or detached. [Effects of the Invention]

[0010] According to the present invention, when the detachable unit is attached, a large third load is applied to the detachable unit to firmly hold the detachable unit, and when the detachable unit is attached or detached, a second load smaller than the third load is applied to the detachable unit, allowing the detachable unit to be easily attached or detached. Thus, the present invention can realize an image forming apparatus that can achieve both the holdability and detachability of the detachable unit. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view showing an external configuration (1) of an image forming apparatus in a state where a front cover is closed and an image forming unit is attached. FIG. [Figure 2] 1 is a perspective view showing the external configuration of an image forming apparatus according to a first embodiment in a state where a front cover is open and an image forming unit is attached; [Figure 3] FIG. 10 is a plan view showing the external configuration (2) of the image forming apparatus in a state where the front cover is closed and the image forming unit is attached. [Figure 4] FIG. 2 is a left side view showing the internal configuration of the image forming apparatus with the front cover closed and the image forming unit attached. [Figure 5] 1 is a perspective view showing an external configuration (1) of an image forming apparatus according to a first embodiment in a state where a front cover is open and an image forming unit is removed. [Figure 6] FIG. 2 is a perspective view showing an external configuration (2) of the image forming apparatus according to the first embodiment in a state where the front cover is open and the image forming unit is removed. [Figure 7] 4 is a cross-sectional view taken along the line AA on the right side of the right frame in FIG. 3, showing the configuration (1) of the right drive mechanism with the front cover closed and the image forming unit attached according to the first embodiment. FIG. [Figure 8] 4 is a cross-sectional view taken along the line BB in FIG. 3, showing the configuration (2) of the right drive mechanism with the front cover closed and the image forming unit attached according to the first embodiment, with appropriate members removed to the left of the right frame. [Figure 9]4 is a cross-sectional view taken along the line AA in FIG. 3, showing the configuration (1) of the right-side drive mechanism in the state where the front cover is open and the image forming unit is attached according to the first embodiment. FIG. [Figure 10] 4 is a cross-sectional view taken along the line BB in FIG. 3 with appropriate members removed, showing the configuration (2) of the right-side drive mechanism in the state where the front cover is open and the image forming unit is attached according to the first embodiment. [Figure 11] 5A to 5C are schematic right side views showing the operation of the right drive mechanism and the removal of the image forming unit according to the first embodiment. [Figure 12] 5A and 5B are schematic right side views showing the operation of the right drive mechanism and the installation of the image forming unit according to the first embodiment. [Figure 13] FIG. 10 is a perspective view showing the configuration (1) of the right-side drive mechanism in the state where the front cover is closed and the image forming unit is attached according to the second embodiment, with appropriate members removed through the right side of the device housing. [Figure 14] 3. FIG. 5 is a cross-sectional view taken along the line AA in FIG. 3, showing the configuration (2) of the right-side drive mechanism in the state where the front cover is closed and the image forming unit is attached according to the second embodiment. [Figure 15] FIG. 10 is a perspective view showing the configuration (3) of the right-side drive mechanism in the state where the front cover is closed and the image forming unit is attached according to the second embodiment, with appropriate members removed through the right side of the device housing. [Figure 16] 10 is a perspective view showing the configuration (1) of the right-side drive mechanism in a state where the front cover is open and the image forming unit is attached according to a second embodiment, with appropriate members removed through the right side of the device housing. FIG. [Figure 17] 3. FIG. 5 is a cross-sectional view taken along the line AA in FIG. 3, showing the configuration (2) of the right-side drive mechanism in the state where the front cover is open and the image forming unit is attached according to the second embodiment. [Figure 18] FIG. 10 is a perspective view showing the configuration (3) of the right-side drive mechanism in the second embodiment with the front cover open and the image forming unit attached, with appropriate members removed through the right side of the device housing. [Figure 19]FIG. 10 is a schematic right side view showing the configuration (1) of a right-side drive mechanism according to another embodiment. [Figure 20] FIG. 10 is a schematic right side view showing the configuration (2) of the right drive mechanism according to another embodiment. [Figure 21] FIG. 10 is a schematic right side view showing the configuration (3) of the right drive mechanism according to another embodiment. [Figure 22] FIG. 10 is a schematic right side view showing the configuration (4) of the right drive mechanism according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, modes for carrying out the invention (hereinafter referred to as embodiments) will be described with reference to the drawings.

[0013] 1. First Embodiment [1-1. External configuration of image forming device] 1, 2, and 3, the image forming apparatus 1 has an exterior housing 2 that is a substantially rectangular parallelepiped and formed by resin molding. Here, the direction from the front to the rear of the housing 2 is defined as the rear direction, the direction from the rear to the front of the housing 2 is defined as the front direction, the direction from the bottom to the top of the housing 2 is defined as the up direction, the direction from the top to the bottom of the housing 2 is defined as the down direction, the direction from the right to the left of the housing 2 is defined as the left direction, and the direction from the left to the right of the housing 2 is defined as the right direction.

[0014] The device housing 2 has a device housing upper surface portion 2u on the top side, a device housing rear surface portion 2b on the rear side, a device housing right surface portion 2r on the right side, and a device housing left surface portion 2l on the left side.

[0015] The device housing 2 is provided with an image forming unit insertion / removal opening 3 in front of and above the image forming unit 10 (described later). The image forming unit insertion / removal opening 3 is a hole that is long in the left-right direction and connects the front side of the device housing 2 to the interior of the device housing 2. The device housing 2 also has a front cover 4 on the front side that can open and close the image forming unit insertion / removal opening 3. When the front cover 4 is in the closed state shown in FIGS. 1, 3, and 4, the front and top surfaces of the front cover 4 close the image forming unit insertion / removal opening 3. The front cover 4 opens and closes the image forming unit insertion / removal opening 3 by rotating about a rotation shaft that extends left-right at the bottom end. When the image forming device 1 is in the open state with the image forming unit insertion / removal opening 3, as shown in FIG. 2, the image forming unit 10 is removably attached to the right frame 8R and the left frame 8L (described later) through the image forming unit insertion / removal opening 3. Therefore, when the image forming unit 10 is removed in the front cover open state, the image forming device 1 changes from the image forming unit installed state in which the image forming unit 10 is installed in a predetermined installation position as shown in Figure 2 to the image forming unit removed state as shown in Figures 5 and 6.

[0016] [1-2. Internal structure of image forming device] 4, the image forming apparatus 1 is a monochrome electrophotographic printer that performs monochrome printing and prints a desired monochrome image on paper P, for example, A3 size, A4 size, etc. Inside the apparatus housing 2, various parts are arranged along a transport path R along which the paper P is transported.

[0017] As shown in Fig. 3, right frames 8R and 8L made of sheet metal are provided inside the device housing 2. The right frame 8R is a plate-like member extending in the up-down and front-rear directions slightly to the left of the device housing right side surface 2r inside the device housing 2. The left frame 8L is a plate-like member extending in the up-down and front-rear directions slightly to the right of the device housing left side surface 2l inside the device housing 2. The right frame 8R and the left frame 8L are fixed to the device housing 2 to support the device housing 2.

[0018] Furthermore, a right guide frame 9R (shown in Fig. 5) is fixed to the left side of the right frame 8R, and a left guide frame 9L (shown in Fig. 6) is fixed to the right side of the left frame 8L. The left guide frame 9L is configured to be almost bilaterally symmetrical with the right guide frame 9R. Hereinafter, the right guide frame 9R and the left guide frame 9L will be collectively referred to as the guide frames 9.

[0019] Inside the device housing 2 (FIGS. 3 and 4), between the right frame 8R and the left frame 8L, an image forming unit 10 corresponding to the color of developer (e.g., black (K) toner) used in the image forming device 1 is provided near the front of the upper side. Hereinafter, the left-right direction perpendicular to the transport direction of the paper P and the thickness direction perpendicular to the paper surface of the paper P will also be referred to as the transport width direction. The image forming unit 10 is fixed by being connected at its right end to the right frame 8R and at its left end to the left frame 8L, thereby maintaining the strength of the right frame 8R and the left frame 8L. The image forming unit 10 forms an electrostatic latent image on the surface of the photosensitive drum 13 by irradiating the surface of the photosensitive drum 13 with light using an LED head as an exposure unit of the head unit 12. Then, a developer supplied from a developer container is applied to the electrostatic latent image, thereby forming a developer image on the surface of the photosensitive drum 13.

[0020] A transfer unit 14 is provided below the image forming unit 10 between the right frame 8R and the left frame 8L inside the device housing 2. The transfer unit 14 has a circular transport belt (not shown) that is provided so as to be able to move freely in the front-to-rear direction along the transport path R, and a transfer roller 15 that is disposed below the photosensitive drum 13 and faces the transport belt across the belt. The transfer roller 15 transfers the developer image formed on the photosensitive drum 13 onto the paper P by charging the paper P with a polarity opposite to that of the developer when the paper P passes between the photosensitive drum 13 and the transport belt.

[0021] Furthermore, inside the device housing 2, a paper tray 16 for storing paper P is provided below the transfer unit 14 between the right frame 8R and the left frame 8L (i.e., at the bottom of the device housing 2). Furthermore, inside the device housing 2, between the right frame 8R and the left frame 8L, a pair of transport rollers for transporting paper P is provided on the transport path R between the paper tray 16 and the transfer unit 14.

[0022] Furthermore, inside the device housing 2, a fixing unit 17 is provided downstream (i.e., rearward) of the image forming unit 10 in the paper transport direction, between the right frame 8R and the left frame 8L. The fixing unit 17 has various components arranged inside a fixing unit housing formed in a substantially box shape. The fixing unit 17 takes in the paper P transported along the transport path R through this paper intake port into the fixing unit housing.

[0023] The fixing unit 17 has a heating roller 18 above the transport path R and a pressure roller 19 disposed below the heating roller 18 and facing the transport path R, and fixes the developer image transferred to the paper P by the transfer unit 14 onto the paper P by applying heat and pressure with the heating roller 18 and pressure roller 19. Furthermore, between the right frame 8R and the left frame 8L inside the device housing 2, on the transport path R between the fixing unit 17 and the paper discharge port 20 (FIG. 1), a pair of discharge rollers and the like are provided, which discharge the paper P from the paper discharge port 20 to a paper stacker section 21 that accumulates the paper P.

[0024] As shown in Figures 10 and 11, the image forming unit 10 has a planar upper end surface 10u that slopes downwards at the top end of both its left and right ends. Note that Figure 11 illustrates the upper end surface 10u at the right end. When the image forming unit 10 is removed from or attached to the image forming apparatus 1, the upper end surface 10u slides against the lock lever locking portion 30b of the lock lever 30 of each of the right drive mechanism 24R and the left drive mechanism 24L (described later). A locking portion 10a is formed on the upper end surface 10u slightly forward of the center in the front-to-rear direction, protruding upward from the upper end surface 10u. The locking portion 10a is shaped like an isosceles triangle and is provided with a removal resistance surface 10ar and an attachment resistance surface 10aa. The removal resistance surface 10ar is the front upper end surface of the locking portion 10a and has a planar shape that slopes upward toward the rear so as to approach the lock lever locking portions 30b of the lock levers 30 of the right drive mechanism 24R and the left drive mechanism 24L. The attachment resistance surface 10aa is the rear upper end surface of the locking portion 10a and has a planar shape that slopes upward toward the front so as to approach the lock lever locking portions 30b of the lock levers 30 of the right drive mechanism 24R and the left drive mechanism 24L.

[0025] As shown in Fig. 11, the upper surface of the guide frames 9 (right guide frame 9R and left guide frame 9L) is shaped to match the shape of the lower surface of the image forming unit 10. Note that Figs. 11 and 12 only show the right drive mechanism 24R. The upper surface of this guide frame 9 has a horizontal surface 9Sh, which is a plane that is approximately horizontal, formed on the rear side, and an inclined surface 9Ss, which is a plane that slopes upward as it approaches the front, formed in front of the horizontal surface 9Sh.

[0026] 7 is provided to the right of the image forming unit 10. The left end of the image forming unit drive member 22, which serves as a first member, is connected to the image forming unit 10 and transmits a drive force to the image forming unit 10 by rotating. The image forming unit drive member 22 is biased by a biasing spring 23 toward the left, toward the inside of the image forming apparatus 1, toward the image forming unit 10. In the front cover closed state (FIG. 7), the image forming unit drive member 22 is connected to the image forming unit 10 and is capable of transmitting a drive force to the image forming unit 10. In the front cover open state (FIG. 9), the image forming unit drive member 22 abuts against a slide lever 26 (described below) and moves in a manner to be pushed rightward against the biasing force of the biasing spring 23, thereby separating from the image forming unit 10 and becoming unable to transmit a drive force to the image forming unit 10.

[0027] [1-3. Right-side drive mechanism configuration] As shown in Figures 3, 7, and 8, a right-side drive mechanism 24R is provided near the right-side frame 8R. The right-side drive mechanism 24R changes the force with which the lock lever 30 presses the image forming unit 10 downward by rotating the tension lever 28 in response to the opening and closing of the front cover 4. The right-side drive mechanism 24R is made up of the front cover 4, the right-side frame 8R, the slide lever 26, the tension lever 28, the lock lever 30, a link lever 32, and a spring 34. Hereinafter, the slide lever 26, the link lever 32, the tension lever 28, and the spring 34 will be collectively referred to as a load change unit 36.

[0028] The slide lever 26 as a moving mechanism is arranged adjacent to the right side of the right frame 8R, is a member that is thin in the left-right direction and extends in the front-to-back and up-to-down directions, and is formed with a guide post sliding groove 26g, a front cover abutment portion 26a, a link lever abutment portion 26b, a drive member sliding groove 26d, a left side flat surface 26S1, an inclined surface 26S2 and a right side flat surface 26S3.

[0029] The guide post sliding groove 26g is formed near the top of the slide lever 26 and is a groove portion that extends in the front-rear direction, penetrating the slide lever 26 in the left-right direction. Two cylindrical guide posts 8a that protrude to the right from the right frame 8R are slidably inserted into this guide post sliding groove 26g.

[0030] The front cover contact portion 26a is formed forward of the guide post sliding groove 26g and has a flat surface facing forward and opposing the slide lever contact portion 4a of the front cover 4 in the front-to-rear direction. On the other hand, the front cover 4 has a slide lever contact portion 4a facing rearward and having a flat surface facing the front cover contact portion 26a in the front-to-rear direction. In the front cover closed state shown in Figures 7 and 8, the front cover 4 causes the slide lever contact portion 4a to contact the front cover contact portion 26a of the slide lever 26 from the front side, thereby restricting the forward movement of the slide lever 26.

[0031] The link lever abutment portion 26b is formed rearward and above the guide post sliding groove 26g, and is a ridge line connecting the rear end surface and left end surface of the slide lever 26, facing the slide lever abutment portion 32b of the link lever 32 in the front-rear direction. In the front cover closed state shown in FIGS. 7 and 8, the slide lever 26 causes the link lever abutment portion 26b to abut against the slide lever abutment portion 32b of the link lever 32 from the front right side, restricting rotation of the link lever 32 in the tension lever down-unrestricted direction Dld (FIG. 9), which is clockwise in plan view. Therefore, in the front cover closed state (FIGS. 7 and 8), the slide lever 26 maintains the link lever 32 in a closed link lever state in which it has been rotated in the tension lever down-restricted direction Dlu, which is counterclockwise in plan view, relative to the open link lever state shown in FIGS. 9 and 10.

[0032] The drive member sliding groove 26d is formed near the bottom of the slide lever 26 and is a groove portion that extends in the front-rear direction, penetrating the slide lever 26 in the left-right direction. The image forming unit drive member 22, which has a substantially cylindrical shape and protrudes leftward from the image forming unit 10, is slidably inserted into the drive member sliding groove 26d.

[0033] The left flat surface 26S1, the inclined surface 26S2, and the right flat surface 26S3 are aligned from front to rear near the bottom of the slide lever 26, each extending over approximately one-third of the length of the slide lever 26 in the front-to-rear direction. A drive member slide groove 26d is formed in the vertical center of the left flat surface 26S1, the inclined surface 26S2, and the right flat surface 26S3. The left flat surface 26S1 faces rightward and extends approximately vertically in the front-to-rear and up-down directions. The inclined surface 26S2 is connected to the rear end of the left flat surface 26S1, faces diagonally forward to the right, and slopes rightward as it extends rearward. The right flat surface 26S3 is connected to the rear end of the inclined surface 26S2, faces rightward and extends approximately vertically in the front-to-rear and up-down directions. Therefore, the right flat surface 26S3 is located to the right of the left flat surface 26S1 in the left-to-right direction. When the front cover is closed (FIG. 7), the image forming unit driving member 22 is located near the front end of the driving member slide groove 26d, and the left side surface of the image forming unit driving member 22 abuts against the left flat surface 26S1.

[0034] The tension lever 28 is a thin, vertically extending plate-like member mounted on the left side of the right frame 8R. The front end of the tension lever 28 is supported by a fulcrum 28a mounted on the right guide frame 9R, and the rear end is rotatable around the fulcrum 28a so that the rear end moves up and down. Hereinafter, the counterclockwise rotation of the tension lever 28 in FIG. 8 to raise the rear end is referred to as the spring compression direction Dc1, and the clockwise rotation of the tension lever 28 in FIG. 10 to lower the rear end is referred to as the spring release direction Dr1. Hereinafter, the position of the tension lever 28, with its rear end at its uppermost position and generally horizontal as shown in FIGS. 7 and 8, is referred to as the tension lever raised state. The position of the tension lever 28 with its rear end at its lowermost position and generally tilted backward as shown in FIGS. 11 and 12 is referred to as the tension lever lowered state. The tension lever 28 also has an inclined rib 28b protruding downward from its underside. The inclined rib 28b is thin in the front-rear direction and extends left-right, with an inclined surface and a horizontal surface formed at the bottom end surface. The inclined surface is formed on the right side and is a plane that slopes downward as it goes left. The horizontal surface is formed on the left side and is a plane that follows the horizontal direction.

[0035] The lock lever 30 is a plate-like member that is thin in the left-right direction and extends in the front-rear direction and is provided above the tension lever 28. The lock lever 30 is supported by a rotation fulcrum 30a provided on the right guide frame 9R at a point forward of the center in the front-rear direction, and is rotatable around the rotation fulcrum 30a so that its front and rear ends move up and down. The lock lever 30 also has an arc-shaped lock lever lock portion 30b at its lower end, forward of the rotation fulcrum 30a. Hereinafter, the direction in which the lock lever 30 rotates counterclockwise in FIG. 8 to lower the lock lever lock portion 30b is also referred to as the lock direction Dl1, and the direction in which the lock lever 30 rotates clockwise in FIG. 10 to raise the lock lever lock portion 30b is also referred to as the unlock direction Dul1.

[0036] The link lever 32 is a thin, plate-like member that is provided below the tension lever 28. The front end of the link lever 32 is supported by a fulcrum 32a provided on the right guide frame 9R, and the rear end is rotatable around the fulcrum 32a so that it can move laterally. The link lever 32 also has an upwardly protruding slanted rib abutment portion 32c. When the link lever 32 rotates from the open link lever state (FIG. 10) in the tension lever downward restriction direction Dlu, the slanted rib abutment portion 32c abuts against the slanted surface of the slanted rib 28b of the tension lever 28, rotating in the spring compression direction Dc1 so as to lift the tension lever 28. When the link lever 32 shifts to the closed link lever state (FIG. 8), the slanted rib abutment portion 32c abuts against the horizontal surface of the slanted rib 28b of the tension lever 28, placing the tension lever 28 in the tension lever raised state.

[0037] The spring 34 is a compression spring, and is disposed between the lower surface of the lock lever 30 near the rear end and the upper surface of the tension lever 28 near the rear end in a state compressed from its natural state. As a result, the spring 34 exerts a restoring force as it tries to return to its natural state, biasing the area near the rear end of the lock lever 30 upward and the area near the rear end of the tension lever 28 downward. As a result, the lock lever 30 is biased in the locking direction Dl1, which is the counterclockwise direction in FIG. 8, around the rotation fulcrum 30a. As a result, the lock lever 30 brings the lock lever locking portion 30b into contact with the locking portion 10a of the image forming unit 10 from above, restricting the upward movement of the image forming unit 10.

[0038] Furthermore, when the tension lever is in the lowered state (FIG. 10), the vertical distance between the lower surface of the lock lever 30 near the rear end and the upper surface of the tension lever 28 near the rear end is wider than when the tension lever is in the raised state (FIG. 8). As a result, the amount by which the spring 34 is compressed by the lock lever 30 and the tension lever 28 is less than when the tension lever is in the raised state (FIG. 8). As a result, the force with which the spring 34 urges the lock lever 30 in the locking direction Dl1 in the lowered state (FIG. 10) is less than when the tension lever is in the raised state (FIG. 8). At this time, the lock lever 30 applies a load Pw from the lock lever lock portion 30b to the lock portion 10a of the image forming unit 10, thereby restricting the upward movement of the image forming unit 10.

[0039] On the other hand, when the tension lever is in the raised state (FIG. 8), the vertical distance between the lower surface of the lock lever 30 near the rear end and the upper surface of the tension lever 28 near the rear end is narrower than when the tension lever is in the lowered state (FIG. 10). Therefore, the amount by which the spring 34 is compressed by the lock lever 30 and the tension lever 28 is greater than when the tension lever is in the lowered state (FIG. 10). As a result, the load Ps, which is the force with which the spring 34 urges the lock lever 30 in the locking direction Dl1, is greater when the tension lever is in the raised state (FIG. 8) than when the tension lever is in the lowered state (FIG. 12). At this time, the lock lever 30 applies a load Ps greater than the load Pw to the lock portion 10a of the image forming unit 10 via the lock lever lock portion 30b, pressing the lock portion 10a more strongly than when the tension lever is in the lowered state (FIG. 10). This restricts the upward movement of the image forming unit 10 and secures the image forming unit 10.

[0040] [1-4. Operation of the right drive mechanism] [1-4-1. Operation of the right drive mechanism when the front cover is closed] Next, the operation of the right-side drive mechanism 24R when the front cover is closed will be described with reference to Figures 7 and 8. When the front cover is closed (Figure 1), the front cover 4 causes the slide lever contact portion 4a to contact the front cover contacted portion 26a of the slide lever 26 from the front side, pushing the slide lever 26 toward the rear inside the image forming apparatus 1 along the guide post 8a and restricting forward movement.

[0041] At this time, the slide lever 26 has its link lever abutment portion 26b abutting against the slide lever abutted portion 32b of the link lever 32 from the front right side, maintaining the link lever 32 in a closed link lever state in which it has been rotated in the tension lever downward restriction direction Dlu from the open link lever state (FIGS. 9 and 10). As a result, the link lever 32 has its inclined rib abutment portion 32c abutting against the horizontal surface of the inclined rib 28b of the tension lever 28, maintaining the tension lever 28 in the tension lever raised state.

[0042] Therefore, the spring 34 is compressed more by the lock lever 30 and the tension lever 28 than when the tension lever is in the lowered state (FIG. 10), generating a strong restoring force. As a result, the lock lever 30 applies a load Ps greater than the load Pw when the tension lever is in the lowered state (FIG. 10) to the lock portion 10a of the image forming unit 10 through the lock lever lock portion 30b, pressing the lock portion 10a of the image forming unit 10 and securing the image forming unit 10. Furthermore, when the front cover is closed, the left side of the image forming unit drive member 22 abuts against the left flat surface 26S1, and is engaged with the image forming unit 10.

[0043] [1-4-2. Operation of the right drive mechanism when changing from the front cover closed state to the front cover open state] Next, the operation of the right drive mechanism 24R when the front cover 4 is opened from the front cover closed state to the front cover open state will be described with reference to FIGS. 7, 8, 9 and 10. FIG.

[0044] When the front cover 4 is opened in the front cover closed state (FIGS. 1, 7, and 8) and enters the front cover open state (FIGS. 2, 9, and 10), the slide lever 26 is no longer restricted from moving forward by the slide lever abutment portion 4a as the slide lever abutment portion 4a of the front cover 4 moves forward. At this time, the slide lever 26 is pushed forward along the guide post 8a while sliding the guide post sliding groove 26g on the guide post 8a by a biasing means (not shown).

[0045] Additionally, as the link lever abutment portion 26b of the slide lever 26 moves forward, the link lever 32's rotation in the tension lever downward non-restriction direction Dld is no longer restricted by the link lever abutment portion 26b, and the link lever 32 becomes rotatable. At this time, the tension lever 28 is pressed downward by the load of the spring 34, and rotates in the spring release direction Dr1 while bringing the inclined surface of the inclined rib 28b into contact with the inclined rib abutment portion 32c of the link lever 32, thereby entering the tension lever downward state.

[0046] Therefore, the vertical distance between the lower surface of the lock lever 30 near the rear end and the upper surface of the tension lever 28 near the rear end is wider than when the tension lever is in the raised state (FIG. 8). As a result, the amount by which the spring 34 is compressed by the lock lever 30 and the tension lever 28 is less than when the tension lever is in the raised state (FIG. 8), and the restoring force it generates is also weaker. As a result, the load Pw that the lock lever 30 applies to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 30b is smaller than the load Ps when the tension lever is in the raised state (FIG. 8).

[0047] Furthermore, when the slide lever 26 moves forward, the slide lever 26 brings the inclined surface 26S2 into contact with the left side surface of the image forming unit drive member 22, thereby pushing the image forming unit drive member 22 outward toward the right, outside the image forming apparatus 1, against the biasing force of the biasing spring 23, and retracting the image forming unit drive member 22, thereby separating it from the image forming unit 10. When the slide lever 26 moves further forward, the slide lever 26 brings the right-side flat surface 26S3 into contact with the left side surface of the image forming unit drive member 22, thereby maintaining the image forming unit drive member 22 in a state separated from the image forming unit 10. This allows the image forming apparatus 1 to put the image forming unit 10 in a state where it can be removed from the inside to the outside of the image forming apparatus 1.

[0048] [1-4-3. Operation of the right drive mechanism when the front cover changes from the open state to the closed state] The above has explained the operation of the right-side drive mechanism 24R when changing from the front cover closed state to the front cover open state. However, when the front cover 4 is closed from the front cover open state to the front cover closed state, each component of the right-side drive mechanism 24R performs the opposite operation to when changing from the front cover open state to the front cover closed state.

[0049] [1-4-4. Operation of the right drive mechanism when removing the image forming unit] Next, the operation of the right drive mechanism 24R when the image forming unit 10 is removed from the image forming apparatus 1 with the front cover open will be described with reference to FIG.

[0050] When the front cover is closed and the image forming unit is attached (Figures 8 and 11(A)), the image forming device 1 applies a load Ps greater than the load Pw to the locking portion 10a of the image forming unit 10 from the locking lever locking portion 30b of the locking lever 30, thereby firmly fixing the image forming unit 10.

[0051] When the front cover 4 is opened (FIGS. 10 and 11B), the tension lever 28 rotates in the spring release direction Dr1, and the tension lever is lowered, as described above. Therefore, the load that the lock lever 30 applies from the lock lever lock portion 30b to the lock portion 10a of the image forming unit 10 becomes a load Pw that is smaller than the load Ps.

[0052] At this time, as described above, the image forming unit driving member 22 is separated from the image forming unit 10. Thereafter, for example, by an operator, the LED head as the first member of the head unit 12 is separated upward from the image forming unit 10, thereby making the image forming unit 10 detachable from the image forming apparatus 101.

[0053] Next, the operator pulls out the image forming unit 10 in a forward and upward direction with the lower surface of the image forming unit 10 abutting against the inclined surface 9Ss of the guide frame 9. At this time, the load Pw applied to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 30b of the lock lever 30 is smaller than the load Ps. Therefore, when the removal resistance surface 10ar of the lock portion 10a slides forward and upward on the lock lever lock portion 30b of the lock lever 30, pushing up the lock lever 30 and rotating it in the unlocking direction Dul1, a climbing load Po, which is slightly larger than the load Pw but smaller than the load Ps, is applied from the lock lever lock portion 30b to the removal resistance surface 10ar. Therefore, the image forming apparatus 1 compresses the spring 34, easily pushing up the lock lever 30 and rotating it in the unlocking direction Dul1 ( FIG. 11(C) ), and moves the lock lever 30 out of the path of travel of the image forming unit 10.

[0054] When the image forming unit 10 is further pulled out in the upward and front direction, the locking portion 10a of the image forming unit 10 moves forward of the lock lever locking portion 30b of the lock lever 30 (FIG. 11(D)). At this time, the spring 34 is slightly restored, and the lock lever 30 rotates in the locking direction Dl1. When the image forming unit 10 is further pulled out, the image forming unit 10 moves while sliding the upper end surface 10u on the lock lever locking portion 30b of the lock lever 30.

[0055] Subsequently, when the image forming unit 10 is removed from the image forming apparatus 1 (FIG. 11(E)), the lock lever locking portion 30b of the lock lever 30 no longer abuts against the upper end surface 10u of the image forming unit 10. At this time, the spring 34 is further restored, and the lock lever 30 further rotates in the locking direction Dl1.

[0056] [1-4-5. Operation of the right drive mechanism when the image forming unit is installed] Next, the operation of the right drive mechanism 24R when the image forming unit 10 is attached to the image forming apparatus 1 with the front cover open will be described with reference to FIG.

[0057] In the front cover open state and the image forming unit detached state (FIG. 12(A)), when the operator pushes the image forming unit 10 downward and rearward with the lower surface of the image forming unit 10 abutting against the inclined surface 9Ss of the guide frame 9, the image forming unit 10 moves while sliding the upper end surface 10u against the lock lever lock portion 30b of the lock lever 30. Next, the attachment resistance surface 10aa of the lock portion 10a of the image forming unit 10 abuts against the lock lever lock portion 30b of the lock lever 30 (FIG. 12(B)). At this time, the load Pw applied to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 30b of the lock lever 30 is smaller than the load Ps. Therefore, when the mounting resistance surface 10aa of the lock portion 10a slides on the lock lever lock portion 30b of the lock lever 30 and moves rearward and downward, pushing up the lock lever 30 and rotating it in the unlocking direction Dul1, a climbing load Po, which is slightly greater than the load Pw but less than the load Ps, is applied from the lock lever lock portion 30b to the mounting resistance surface 10aa. As a result, the image forming apparatus 1 compresses the spring 34, allowing the lock lever 30 to be easily pushed up by its own weight or by a light force from the operator and rotated in the unlocking direction Dul1 (FIG. 12C), and the lock lever 30 is retracted from the path of travel of the image forming unit 10.

[0058] As the image forming unit 10 continues to be pushed in, the image forming unit 10 moves rearward and downward while sliding the upper end surface 10u against the lock lever lock portion 30b of the lock lever 30, and moves to the predetermined mounting position (FIGS. 10 and 12(D)). At this time, a load Pw smaller than the climbing load Po is applied from the lock lever lock portion 30b of the lock lever 30 to the lock portion 10a of the image forming unit 10.

[0059] Next, when the front cover 4 is closed and enters the front cover closed state (Figures 8 and 12(E)), as described above, the image forming device 1 applies a load Ps greater than the load Pw to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 30b of the lock lever 30, thereby firmly fixing the image forming unit 10.

[0060] [1-5. Configuration and operation of the left drive mechanism] The left-side drive mechanism 24L is provided near the left frame 8L (FIG. 3). The left-side drive mechanism 24L is configured substantially symmetrically with the right-side drive mechanism 24R, and does not have mechanisms corresponding to the left-side flat surface 26S1, the inclined surface 26S2, and the right-side flat surface 26S3. Furthermore, the image forming unit drive member 22 is not provided on the left side of the image forming unit 10. Because the left-side drive mechanism 24L is configured substantially similarly to the right-side drive mechanism 24R, a description thereof will be omitted. Furthermore, because the left-side drive mechanism 24L is symmetrical with the right-side drive mechanism 24R and operates substantially in the same manner, a description thereof will be omitted.

[0061] [1-6. Effects, etc.] In the above configuration, when the image forming device 1 is in an image forming unit mounted state in which the image forming unit 10 is mounted in the device housing 2 and in a front cover closed state in which the image forming unit 10 is not removed from the device housing 2, the lock lever 30 applies a load Ps that is greater than the load Pw to the image forming unit 10, thereby restricting the range of movement of the image forming unit 10 and firmly locking it.

[0062] On the other hand, when the front cover 4 is opened to detach the image forming unit 10 from the device housing 2 and the image forming device 1 enters the front cover open state, the load change section 36 is moved in conjunction with the front cover 4, and the load applied to the image forming unit 10 from the lock lever 30 is set to a load Pw which is smaller than the load Ps, thereby reducing the force that locks the image forming unit 10. Therefore, the image forming device 1 allows the operator to easily detach the image forming unit 10 from the device housing 2.

[0063] Furthermore, the image forming apparatus 1 moves the load change section 36 in conjunction with the opening and closing of the front cover 4, thereby changing the load applied from the lock lever 30 to the image forming unit 10. This eliminates the need for the operator to perform an operation to change the load applied from the lock lever 30 to the image forming unit 10 in addition to the operation of opening and closing the front cover 4, thereby reducing the operator's workload.

[0064] In this way, the image forming apparatus 1 changes the load applied to the image forming unit 10 from the lock lever 30 by the load change section 36 in conjunction with the opening and closing of the front cover 4, switching between a state in which the image forming unit 10 is firmly locked and a state in which the locking force on the image forming unit 10 is weakened. As a result, the image forming apparatus 1 can achieve both strong fixation of the image forming unit 10 and improved ease of attachment and detachment of the image forming unit 10 with a simple configuration.

[0065] Furthermore, the image forming apparatus 1 moves the slide lever 26 in the load changing section 36 in the front-rear direction in conjunction with the opening and closing of the front cover 4, and causes the left side flat surface 26S1 or the right side flat surface 26S3 to abut against the image forming unit driving member 22, thereby moving the image forming unit driving member 22 toward and away from the image forming unit 10. Therefore, the image forming apparatus 1 eliminates the need for the operator to perform the operation of moving the image forming unit driving member 22 toward and away from the image forming unit 10 in addition to the operation of opening and closing the front cover 4, thereby reducing the operator's workload.

[0066] Furthermore, when an operator pushes image forming unit 10 rearward to install image forming unit 10 in device housing 2, image forming unit 10 causes installation resistance surface 10aa of lock portion 10a of image forming unit 10 to abut against lock lever lock portion 30b of lock lever 30, and image forming unit 10 pushes up lock lever 30, causing lock portion 10a to overcome lock lever lock portion 30b and reach the installation position. At this time, image forming apparatus 1 applies an overtaking load Po, which is slightly greater than load Pw but less than load Ps, from lock lever lock portion 30b to removal resistance surface 10ar. This allows image forming apparatus 1 to give the operator a tactile sensation (also referred to as a locking sensation or insertion sensation) that image forming unit 10 has reached the installation position, allowing the operator to recognize that image forming unit 10 has reached the installation position.

[0067] In this way, in the image forming apparatus 1, the member that firmly locks the image forming unit 10 and the member that gives the operator the feeling that the image forming unit 10 has been inserted are shared by the lock lever 30. Therefore, the image forming apparatus 1 can omit components compared to when a separate member that firmly locks the image forming unit 10 and a separate member that gives the operator the feeling that the image forming unit 10 has been inserted are provided.

[0068] According to the above configuration, the image forming device 1 is provided with an image forming unit 10 that can be inserted into or removed from the device housing 2 serving as the device main body, a load supplying member that applies a load to the image forming unit 10, and a load changing section 36 that applies a first load, a climbing load Po, to the image forming unit 10 by the lock lever 30 when the image forming unit 10 passes through the lock lever lock section 30b, which is a predetermined position, during the insertion or removal of the image forming unit 10 into or from the device housing 2, applies a second load, a load Pw, to the image forming unit 10 by the lock lever 30 when the image forming unit 10 is in a position where it is attached to the device housing 2, and applies a third load, a load Ps, which is greater than the load Pw, to the image forming unit 10 by the lock lever 30 when restricting the range of movement of the image forming unit 10 after the image forming unit 10 has been attached to the device housing 2.

[0069] Furthermore, according to the above configuration, the image forming device 1 is provided with an image forming unit 10 that can be inserted into or removed from the device housing 2, a load supplying member that applies a load to the image forming unit 10, and a load changing section 36 that applies a climbing load Po to the image forming unit 10 by the lock lever 30 when the image forming unit 10 passes through the lock lever lock section 30b, which is a predetermined position, during the insertion or removal of the image forming unit 10 into or from the device housing 2, applies a load Pw to the image forming unit 10 by the lock lever 30 when the image forming unit 10 is attached to the device housing 2, and applies a load Ps that is larger than the load Pw to the image forming unit 10 by the lock lever 30 when image formation is possible.

[0070] As a result, when the image forming unit 10 is attached, the image forming device 1 applies a large load Ps to the image forming unit 10 to firmly hold the image forming unit 10, and when the image forming unit 10 is attached or detached, the load applied to the image forming unit 10 is a load Pw which is smaller than the load Ps, allowing the image forming unit 10 to be easily attached or detached.

[0071] 2. Second Embodiment [2-1. Configuration of image forming device] The image forming apparatus 101 (FIGS. 1 and 3) according to the second embodiment differs from the image forming apparatus 1 according to the first embodiment in that it has a right drive mechanism 124R and a left drive mechanism 124L instead of the right drive mechanism 24R and the left drive mechanism 24L, respectively, but is otherwise configured similarly.

[0072] [2-2. Right-side drive mechanism configuration] 13, 14, and 15, in which the same reference numerals are used to denote components corresponding to those in FIGS. 7 and 8, a right-side drive mechanism 124R is provided near the right-side frame 108R. The right-side drive mechanism 124R moves the slide piece 41 up and down in response to the opening and closing of the front cover 4, thereby changing the force with which the lock lever 130 presses the image forming unit 10 downward.

[0073] The right-side drive mechanism 124R according to the second embodiment differs from the right-side drive mechanism 24R according to the first embodiment in that it includes a right-side frame 108R instead of the right-side frame 8R, a slide lever 126 instead of the slide lever 26, a slide piece 41 instead of the tension lever 28 and the link lever 32, a lock lever 130 instead of the lock lever 30, and a spring 42 instead of the spring 34, but is otherwise configured similarly. Hereinafter, the slide lever 126, slide piece 41, spring 42, and lock lever 130 will also be collectively referred to as a load change unit 136.

[0074] The right frame 108R according to the second embodiment differs from the right frame 8R according to the first embodiment in that it includes a guide groove 108a. The guide groove 108a is formed near the rear end of the slide lever 126 in the front-rear direction, penetrates the right frame 108R in the left-right direction, and has a shape resembling a capital letter "L" rotated 180 degrees when viewed from the right side. The guide groove 108a includes a vertical groove portion 108av and a front-rear groove portion 108ah. The vertical groove portion 108av has a linear shape with its upper end slightly tilted forward relative to the vertical direction, and a cylindrical post 12hv protruding to the right from the head holder 12h (described later) is slidably inserted into the vertical groove portion 108ah. The vertical groove portion 108ah has a linear shape extending horizontally forward from the upper end of the vertical groove portion 108av, and a cylindrical post 12hh protruding to the right from the head holder 12h is slidably inserted into the vertical groove portion 108ah.

[0075] The head holder 12h holds the LED head 12d (FIG. 16). When the front cover is closed (FIGS. 13, 14, and 15), the head holder 12h descends, bringing the LED head 12d into contact with the image forming unit 10 and positioning the post 12hv near the lower end of the vertical groove 108av. When the front cover is open (FIGS. 16, 17, and 18), the head holder 12h ascends while tilting its upper end forward, separating the LED head 12d upward from the image forming unit 10 and positioning the post 12hv near the upper end of the vertical groove 108av. In this state, the LED head 12d is not in contact with the image forming unit 10, so the image forming unit 10 is detachable from the image forming apparatus 101.

[0076] The slide lever 126 according to the second embodiment differs from the slide lever 26 according to the first embodiment in that it has an additional hole 126c and a slide piece abutment inclined surface 126i instead of the link lever abutment portion 26b, but is otherwise configured in the same manner.

[0077] The hole 126c is formed in the rear end of the slide lever 126 below and behind the guide post slide groove 26g, and passes through the slide lever 126 in the left-right direction. The post 12hh is inserted into and engaged with this hole 126c.

[0078] In the front cover closed state shown in FIGS. 13, 14, and 15, the slide lever abutting portion 4a of the front cover 4 abuts the front cover abutting portion 26a of the slide lever 126 from the front side, restricting the forward movement of the slide lever 126. At this time, compared to the front cover open state (FIGS. 16, 17, and 18), the post 12hh of the head holder 12h engaged with the hole 126c of the slide lever 126 also moves rearward together with the slide lever 126 along the front-rear groove 108ah. Accompanying the rearward movement of the slide lever 126, the post 12hh moves downward along the rearward-sloping vertical groove 108av of the right frame 8R. Therefore, in the front cover closed state (FIGS. 13, 14, and 15), the LED head 12d abuts against the image forming unit 10. Furthermore, in the front cover closed state (FIGS. 13, 14 and 15), the image forming unit driving member 22 is engaged with the image forming unit 10, similarly to the first embodiment.

[0079] The slide piece abutment inclined surface 126i is provided at the upper end of the slide lever 126, has a length of about one-third of the slide lever 126 in the front-to-rear direction, and is a flat surface above the slide piece 41 that slopes upward as it moves rearward so as to face the slide piece 41 in the vertical direction, and faces downward and rearward.

[0080] When the front cover is closed (Figures 13, 14, and 15), the slide lever 126 abuts the front end portion, which is the portion of the slide piece abutment inclined surface 126i that is lower in the vertical direction, against the slide piece 41 from above, greatly compressing the spring 42 against the restoring force of the spring 42 and moving the slide piece 41 significantly downward.

[0081] On the other hand, when the front cover is in the open state (Figures 16, 17, and 18), the rear end portion of the slide lever 126, which is the part of the slide piece abutment inclined surface 126i that is taller in the vertical direction, abuts against the slide piece 41 from above, compressing the spring 42 slightly against the restoring force of the spring 42 and moving the slide piece 41 slightly downward.

[0082] The slide piece 41 is a thin, plate-like member that is provided on the left side of the right frame 8R. The slide piece 41 is capable of reciprocating vertically within a groove provided in the right guide frame 9R. Hereinafter, the direction in which the slide piece 41 ascends will also be referred to as the spring release direction Dr2, and the direction in which the slide piece 41 descends will also be referred to as the spring compression direction Dc2. In addition, the state in which the slide piece 41 is positioned at the lowest position as shown in Figures 14 and 15 will also be referred to as the slide piece descended state, and the state in which the slide piece 41 is positioned at the highest position as shown in Figures 17 and 18 will also be referred to as the slide piece ascended state.

[0083] The lock lever 130 is provided below the slide piece 41, has a horizontally flat upper surface, and has an arc-shaped lock lever lock portion 130b at its lower end, and is capable of reciprocating up and down. Hereinafter, the direction in which the lock lever 130 descends will also be referred to as the lock direction Dl2, and the direction in which the lock lever 130 ascends will also be referred to as the unlock direction Dul2.

[0084] The spring 42 is a compression spring, and is disposed between the lower surface of the slide piece 41 and the upper surface of the lock lever 130 in a state compressed from its natural state. Therefore, the spring 42 biases the slide piece 41 upward and the lock lever 130 downward due to a restoring force that attempts to return to its natural state. As a result, the lock lever 130 is biased downward in the locking direction Dl1. As a result, the lock lever 130 causes the lock lever lock portion 130b to abut against the lock portion 10a of the image forming unit 10 from above, restricting upward movement of the image forming unit 10.

[0085] Furthermore, in the slide piece raised state (FIGS. 17 and 18), the vertical distance between the upper surface of the lock lever 130 and the lower surface of the slide piece 41 is wider than in the slide piece lowered state (FIGS. 14 and 15). Therefore, the amount by which the spring 42 is compressed by the lock lever 130 and the slide piece 41 is less than in the slide piece lowered state (FIGS. 14 and 15). As a result, the force with which the spring 42 urges the lock lever 130 in the locking direction Dl1 in the slide piece raised state (FIGS. 17 and 18) is smaller than in the slide piece lowered state (FIGS. 14 and 15). At this time, the lock lever 130 applies a load Pw from the lock lever lock portion 130b to the lock portion 10a of the image forming unit 10, thereby restricting the upward movement of the image forming unit 10.

[0086] On the other hand, in the slide piece lowered state (FIGS. 14 and 15), the vertical distance between the upper surface of the lock lever 130 and the lower surface of the slide piece 41 is narrower than in the slide piece raised state (FIGS. 17 and 18). Therefore, the amount by which the spring 42 is compressed by the lock lever 130 and the slide piece 41 is greater than in the slide piece raised state (FIGS. 17 and 18). As a result, the force with which the spring 42 urges the lock lever 130 in the locking direction Dl1 in the slide piece lowered state (FIGS. 14 and 15) is greater than in the slide piece raised state (FIGS. 17 and 18). At this time, the lock lever 130 applies a load Ps greater than the load Pw to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 130b, pressing the lock portion 10a more strongly than in the slide piece raised state (FIGS. 17 and 18). This restricts the upward movement of the image forming unit 10 and secures the image forming unit 10.

[0087] [2-3. Operation of the right drive mechanism] [2-3-1. Operation of the right drive mechanism when the front cover is closed] Next, the operation of the right-side drive mechanism 124R when the front cover is closed will be described with reference to Figures 13, 14, and 15. When the front cover is closed (Figure 1), the front cover 4 causes the slide lever abutting portion 4a to abut against the front cover abutting portion 26a of the slide lever 126 from the front side, pushing the slide lever 126 toward the rear inside the image forming device 101 along the guide post 8a, thereby restricting forward movement.

[0088] At this time, the slide lever 126 abuts the front end portion, which is the portion of the slide piece abutment inclined surface 126i that is the lower part in the vertical direction, against the slide piece 41 from above, compressing the spring 42 greatly against the restoring force of the spring 42 and moving the slide piece 41 significantly toward the spring compression direction Dc2, thereby lowering the slide piece.

[0089] Therefore, the spring 42 is compressed more by the lock lever 130 and the slide piece 41 than in the slide piece raised state (FIGS. 17 and 18), generating a strong restoring force. As a result, the lock lever 130 applies a load Ps larger than the load Pw in the slide piece raised state (FIGS. 17 and 18) to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 130b, pressing the lock portion 10a to fix the image forming unit 10.

[0090] The head holder 12h is in a state in which the post 12hv is positioned near the lower end of the vertical groove portion 108av, and the LED head 12d is in contact with the image forming unit 10. Furthermore, when the front cover is closed, the left side surface of the image forming unit driving member 22 is in contact with the left flat surface 26S1, and the image forming unit driving member 22 is engaged with the image forming unit 10.

[0091] [2-3-2. Operation of the right drive mechanism when changing from the front cover closed state to the front cover open state] Next, the operation of the right drive mechanism 124R when the front cover 4 is opened from the front cover closed state to the front cover open state will be described with reference to FIGS. 13, 14, 15, 16, 17 and 18.

[0092] When the front cover 4 is opened in the front cover closed state (FIGS. 1, 13, 14, and 15) and assumes the front cover open state (FIGS. 2, 16, 17, and 18), the slide lever 126 is no longer restricted from moving forward by the slide lever abutment portion 4a as the slide lever abutment portion 4a of the front cover 4 moves forward. At this time, the slide lever 126 is pushed forward along the guide post 8a while sliding the guide post sliding groove 26g on the guide post 8a by a biasing means (not shown).

[0093] At this time, the slide lever 126 moves forward while bringing the slide piece abutment inclined surface 126i into contact with the slide piece 41, thereby gradually moving the slide piece 41 in the spring release direction Dr2. When the front cover is in the open state (FIGS. 2, 16, 17, and 18), the slide lever 126 brings the rear end portion of the slide piece abutment inclined surface 126i, which is the portion that is taller in the vertical direction, into contact with the slide piece 41 from above, compressing the spring 42 slightly against the restoring force of the spring 42 and bringing the slide piece into the raised state.

[0094] Therefore, the vertical distance between the upper surface of the lock lever 130 and the lower surface of the slide piece 41 is wider than when the slide piece is in the lowered state (FIGS. 14 and 15). As a result, the amount by which the spring 42 is compressed by the lock lever 130 and the slide piece 41 is smaller than when the slide piece is in the lowered state (FIGS. 14 and 15), and the restoring force it generates is also weaker. As a result, the load Pw that the lock lever 130 applies to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 130b is smaller than the load Ps when the slide piece is in the lowered state (FIGS. 14 and 15).

[0095] Furthermore, when the slide lever 126 moves forward, the post 12hh moves forward along the longitudinal groove 108ah, and the head holder 12h moves forward while tilting its upper end forward. At this time, the post 12hv moves diagonally upward and forward along the vertical groove 108av, and the head holder 12h moves diagonally upward and forward. As a result, the head holder 12h rises, separating the LED head 12d upward from the image forming unit 10.

[0096] Furthermore, when the slide lever 126 moves forward, the slide lever 126 brings the inclined surface 26S2 into contact with the left side surface of the image forming unit drive member 22, thereby pushing the image forming unit drive member 22 outward toward the right, toward the outside of the image forming apparatus 101, against the biasing force of the biasing spring 23, and retracting the image forming unit drive member 22, thereby separating it from the image forming unit 10. When the slide lever 126 moves further forward, the slide lever 126 brings the right-side flat surface 26S3 into contact with the left side surface of the image forming unit drive member 22, thereby maintaining the image forming unit drive member 22 in a state separated from the image forming unit 10. This allows the image forming apparatus 101 to be in a state in which the image forming unit 10 can be removed from the inside to the outside of the image forming apparatus 101.

[0097] [2-3-3. Operation of the right drive mechanism when the front cover changes from the open state to the closed state] The above describes the operation of the right-side drive mechanism 124R when changing from the front cover closed state to the front cover open state. However, when the front cover 4 is closed from the front cover open state to the front cover closed state, each component of the right-side drive mechanism 124R performs the opposite operation to when changing from the front cover open state to the front cover closed state.

[0098] [2-3-4. Operation of the right drive mechanism when removing the image forming unit] Next, the operation of the right drive mechanism 124R when the image forming unit 10 is removed from the image forming apparatus 101 with the front cover open will be described with reference to FIGS.

[0099] When the front cover is closed and the image forming unit is attached (Figure 15), the image forming device 101 applies a load Ps greater than the load Pw to the locking portion 10a of the image forming unit 10 from the locking lever locking portion 130b of the locking lever 130, thereby firmly fixing the image forming unit 10.

[0100] When the front cover 4 is opened (FIG. 18), the slide piece 41 moves in the spring release direction Dr2 and enters the slide piece raised state, as described above. Therefore, the load that the lock lever 130 applies from the lock lever lock portion 130b to the lock portion 10a of the image forming unit 10 becomes a load Pw that is smaller than the load Ps.

[0101] At this time, as described above, the image forming unit drive member 22 is separated from the image forming unit 10, and the LED head 12d of the head unit 12 is separated upward from the image forming unit 10, so that the image forming unit 10 becomes detachable from the image forming device 101.

[0102] Next, the operator pulls out the image forming unit 10 in a forward and upward direction with the lower surface of the image forming unit 10 abutting against the inclined surface 9Ss of the guide frame 9. At this time, the load Pw applied to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 130b of the lock lever 130 is smaller than the load Ps. Therefore, when the removal resistance surface 10ar of the lock portion 10a slides on the lock lever lock portion 130b of the lock lever 130 and moves forward and upward, pushing up the lock lever 130 in the unlocking direction Dul2, a climbing load Po, which is slightly larger than the load Pw but smaller than the load Ps, is applied from the lock lever lock portion 130b to the removal resistance surface 10ar. Therefore, the image forming apparatus 101 compresses the spring 42, easily pushing up the lock lever 130 and moving it in the unlocking direction Dul2, thereby retracting the lock lever 130 from the path of travel of the image forming unit 10.

[0103] When the image forming unit 10 is further pulled out in the front-upward direction, the locking portion 10a of the image forming unit 10 moves forward of the lock lever locking portion 130b of the lock lever 130. At this time, the spring 42 is slightly restored, and the lock lever 130 moves downward in the locking direction Dl2. When the image forming unit 10 is further pulled out, the image forming unit 10 moves while sliding the upper end surface 10u on the lock lever locking portion 130b of the lock lever 130.

[0104] Subsequently, when the image forming unit 10 is removed from the image forming apparatus 101, the lock lever lock portion 130b of the lock lever 130 no longer abuts against the upper end surface 10u of the image forming unit 10. At this time, the spring 42 is further restored, and the lock lever 130 further descends in the lock direction Dl2.

[0105] [2-3-5. Operation of the right drive mechanism when the image forming unit is installed] Next, the operation of the right drive mechanism 124R when the image forming unit 10 is attached to the image forming apparatus 101 with the front cover open will be described with reference to FIGS.

[0106] In the front cover open state and the image forming unit detached state, when the operator pushes the image forming unit 10 downward and rearward with the lower surface of the image forming unit 10 abutting against the inclined surface 9Ss of the guide frame 9, the image forming unit 10 moves while the upper end surface 10u slides against the lock lever lock portion 130b of the lock lever 130. Next, the attachment resistance surface 10aa of the lock portion 10a of the image forming unit 10 abuts against the lock lever lock portion 130b of the lock lever 130. At this time, the load Pw applied to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 130b of the lock lever 130 is smaller than the load Ps. Therefore, when the mounting resistance surface 10aa of the lock portion 10a slides on the lock lever lock portion 130b of the lock lever 130 and moves rearward and downward, pushing up the lock lever 130 in the unlocking direction Dul2, a climbing load Po, which is slightly greater than the load Pw but less than the load Ps, is applied from the lock lever lock portion 130b to the mounting resistance surface 10aa. Therefore, the image forming apparatus 101 compresses the spring 42 and easily pushes up the lock lever 130 by its own weight or by a light force from the operator, lifting it in the unlocking direction Dul2 and retracting the lock lever 130 from the path of travel of the image forming unit 10.

[0107] As the image forming unit 10 continues to be pushed in, the image forming unit 10 moves rearward and downward while sliding the upper end surface 10u against the lock lever lock portion 130b of the lock lever 130, and moves to the predetermined installation position (FIG. 18). At this time, a load Pw smaller than the climbing load Po is applied from the lock lever lock portion 130b of the lock lever 130 to the lock portion 10a of the image forming unit 10.

[0108] Next, when the front cover 4 is closed and enters the front cover closed state (Figure 15), as described above, the image forming device 101 applies a load Ps greater than the load Pw to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 130b of the lock lever 130, thereby firmly fixing the image forming unit 10.

[0109] [2-4. Configuration and operation of the left drive mechanism] A left-side drive mechanism 124L is provided near the left-side frame 108L (FIG. 3) corresponding to the left-side frame 8L according to the first embodiment. The left-side drive mechanism 124L is configured substantially symmetrically with the right-side drive mechanism 124R, and does not include mechanisms corresponding to the left-side flat surface 26S1, the inclined surface 26S2, and the right-side flat surface 26S3. Furthermore, the image forming unit drive member 22 is not provided on the left side of the image forming unit 10. Because the left-side drive mechanism 124L is configured substantially similarly to the right-side drive mechanism 124R, a description thereof will be omitted. Furthermore, because the left-side drive mechanism 124L is symmetrical with the right-side drive mechanism 124R and operates substantially similarly, a description thereof will be omitted.

[0110] [2-5. Effects, etc.] In the above configuration, the image forming apparatus 101 moves the slide lever 26 in the load changing section 36 in the front-rear direction in conjunction with the opening and closing of the front cover 4, and moves the head holder 12h in the front-rear direction while tilting it, thereby moving the LED head 12d toward and away from the image forming unit 10. This eliminates the need for the operator to perform the operation of moving the LED head 12d toward and away from the image forming unit 10 in addition to the operation of opening and closing the front cover 4, thereby reducing the operator's workload.

[0111] In other respects as well, image forming apparatus 101 according to the second embodiment can achieve the same effects as image forming apparatus 1 according to the first embodiment.

[0112] 3. Other Embodiments [3-1. Other embodiment 1] The image forming apparatus 1 according to the first embodiment described above may be provided with a right-side drive mechanism 224R shown in Fig. 19, in which the same reference numerals are used for components corresponding to those in Fig. 11, instead of the right-side drive mechanism 24R. The right-side drive mechanism 224R differs from the right-side drive mechanism 24R in that a spring 35 and a spring retainer 50 are added, but the other points are similarly configured.

[0113] The spring 35 is a compression spring, and is arranged, for example, behind the spring 34, in a state compressed from its natural state, between the lower surface of the lock lever 30 near the rear end and the upper surface of the tension lever 28 near the rear end. The spring retainer 50 is arranged above the spring 35 so as to face the spring 35 in the vertical direction, and is a member that is movable in the vertical direction. The tension lever 28 may also be fixed rather than movable in the spring release direction Dr1 and the spring compression direction Dc1.

[0114] In this configuration, when the front cover is closed (FIG. 19(A)), the spring retainer 50 is located above the spring 35 and does not abut against the spring 35. Therefore, both the springs 34 and 35 are compressed by the lock lever 30 and the tension lever 28, generating a strong restoring force. As a result, the lock lever 30 applies a load Ps greater than the load Pw (FIG. 19(B)) to the lock portion 10a of the image forming unit 10 through the lock lever lock portion 30b, thereby pressing the lock portion 10a and securing the image forming unit 10. On the other hand, when the front cover is open (FIG. 19(B)), the spring retainer 50 descends and abuts against the spring 35, compressing it, so that the upper end of the spring 35 is located below the lock lever 30 and does not abut against the lock lever 30. Therefore, only the spring 34 is compressed by the lock lever 30 and the tension lever 28, generating a weak restoring force. As a result, the load Pw that the lock lever 30 applies to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 30b is smaller than the load Ps (FIG. 19A).

[0115] Furthermore, the image forming apparatus 1 may be provided with a left-side drive mechanism (not shown) that is bilaterally symmetrical to the right-side drive mechanism 224R (FIG. 19), instead of the left-side drive mechanism 24L.

[0116] [3-2. Other embodiment 2] Furthermore, the image forming apparatus 1 according to the first embodiment described above may be provided with a right-side drive mechanism 324R shown in Figure 20, in which the same reference numerals are used for components corresponding to those in Figure 11, instead of the right-side drive mechanism 24R. The right-side drive mechanism 324R differs from the right-side drive mechanism 24R in that it additionally includes a tension lever 52, a spring 53, and a tension lever retainer 54, but is otherwise configured similarly.

[0117] The tension lever 52 is located above the tension lever 28, facing the tension lever 28 in the vertical direction across the lock lever 30, and is a member that can move up and down. The spring 53 is a compression spring and is located between the upper surface of the lock lever 30 near its rear end and the underside of the tension lever 52. The spring 53's restoring force, which tends to return to its natural state, biases the rear end of the lock lever 30 downward and the tension lever 52 upward. The spring 53 biases the lock lever 30 clockwise in FIG. 20 around the rotation fulcrum 30a. Meanwhile, the spring 34 biases the lock lever 30 counterclockwise in FIG. 20 around the rotation fulcrum 30a. The tension lever retainer 54 is located above the tension lever 52 and is a member that can move up and down. The tension lever 28 may be fixed rather than movable in the spring release direction Dr1 and the spring compression direction Dc1.

[0118] In this configuration, in the front cover closed state (FIG. 20(A)), the tension lever retaining member 54 abuts against the upper side of the tension lever 52, restricting the upward movement of the tension lever 52. At this time, the spring 53 is compressed less by the lock lever 30 and the tension lever 52 than in the front cover open state (FIG. 20(B)), generating a weaker restoring force. As a result, the counterclockwise biasing force of the spring 34 in FIG. 20 is not largely offset by the clockwise biasing force of the spring 53 in FIG. 20, and the lock lever locking portion 30b presses the locking portion 10a of the image forming unit 10 with a load Ps greater than the load Pw (FIG. 20(B)), thereby securing the image forming unit 10. On the other hand, in the front cover open state (FIG. 20(B)), the tension lever retaining member 54 descends, pushing down the tension lever 52 and compressing the spring 53. Therefore, the spring 53 generates a stronger restoring force than in the front cover closed state (FIG. 20(A)). 20 by the spring 34 is largely offset by the clockwise biasing force of the spring 53. As a result, the load Pw that the lock lever 30 applies to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 30b is smaller than the load Ps (FIG. 20(A)).

[0119] Furthermore, the image forming apparatus 1 may be provided with a left-side drive mechanism (not shown) that is bilaterally symmetrical to the right-side drive mechanism 324R (FIG. 20), instead of the left-side drive mechanism 24L.

[0120] [3-3. Other embodiment 3] Furthermore, the image forming apparatus 1 according to the first embodiment described above may be provided with a right-side drive mechanism 424R shown in Fig. 21, in which the same reference numerals are used for components corresponding to those in Fig. 11, instead of the right-side drive mechanism 24R. The right-side drive mechanism 424R differs from the right-side drive mechanism 24R in that a spring retaining member 56 is added, but is otherwise configured similarly.

[0121] The spring retainer 56 is a member that is disposed behind the spring 34 and is movable in the front-to-rear direction. The tension lever 28 may be fixed rather than movable in the spring release direction Dr1 and the spring compression direction Dc1.

[0122] In this configuration, when the front cover is closed (FIG. 21(A)), the spring retainer 56 moves forward and is inserted into the wound portion of the spring 34. Therefore, only the wound portion of the spring 34 between the spring retainer 56 and the lock lever 30 expands or contracts. As a result, the lock lever 30 applies a load Ps greater than the load Pw (FIG. 21(B)) to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 30b, pressing the lock portion 10a of the image forming unit 10 and securing the image forming unit 10. On the other hand, when the front cover is open (FIG. 21(B)), the spring retainer 56 moves rearward and is positioned outside the wound portion of the spring 34. Therefore, the entire wound portion of the spring 34 between the tension lever 28 and the lock lever 30 expands or contracts, generating a weak restoring force. As a result, the load Pw applied by the lock lever 30 to the lock portion 10a of the image forming unit 10 from the lock lever lock portion 30b is smaller than the load Ps (FIG. 21(A)).

[0123] Furthermore, the image forming apparatus 1 may be provided with a left-side drive mechanism (not shown) that is bilaterally symmetrical to the right-side drive mechanism 424R (FIG. 21), instead of the left-side drive mechanism 24L.

[0124] [3-4. Other embodiment 4] Furthermore, the image forming apparatus 1 according to the first embodiment described above may be provided with a right-side drive mechanism 524R shown in Fig. 22, in which the same reference numerals are used for components corresponding to those in Fig. 11, instead of the right-side drive mechanism 24R. The right-side drive mechanism 524R differs from the right-side drive mechanism 24R in that a stopper 58 is added, but is otherwise configured similarly.

[0125] The stopper 58 is a member that is located near the lower end surface of the rear end of the lock lever 30 behind the spring 34 and is movable in the front-to-rear direction. The tension lever 28 may be fixed rather than movable in the spring release direction Dr1 and the spring compression direction Dc1.

[0126] In this configuration, when the front cover is closed (FIG. 22(A)), the stopper 58 moves forward and abuts against the lower end surface of the rear end of the lock lever 30, which is rearward of the rotation fulcrum 30a. This restricts the lock lever 30 from rotating in the unlocking direction Dul1. On the other hand, when the front cover is open (FIG. 22(B)), the stopper 58 moves rearward and is positioned rearward of the lock lever 30. This allows the lock lever 30 to rotate in the unlocking direction Dul1.

[0127] Furthermore, the image forming apparatus 1 may be provided with a left-side drive mechanism (not shown) that is bilaterally symmetrical to the right-side drive mechanism 524R (FIG. 22), instead of the left-side drive mechanism 24L.

[0128] [3-5. Other embodiment 5] Furthermore, in the first embodiment described above, the image forming apparatus 1 has been described as moving the lock lever 30 by rotating the tension lever 28 in conjunction with the opening and closing of the front cover 4, thereby changing the force with which the lock lever 30 presses the image forming unit 10 downward. However, the present invention is not limited to this. For example, if there is a cover covering the image forming unit 10, the image forming apparatus 1 may move the lock lever 30 in conjunction with the opening and closing of the cover, or may move the lock lever 30 by an operator's operation, and the movement of the lock lever 30 does not have to be linked to the opening and closing of the front cover 4. The same applies to the second embodiment.

[0129] [3-6. Other embodiment 6] Furthermore, in the first embodiment described above, the image forming apparatus 1 has been described as connecting or separating the image forming unit driving member 22 to or from the image forming unit 10 by bringing the image forming unit driving member 22 into contact with the left flat surface 26S1 or the right flat surface 26S3 of the slide lever 26 in conjunction with the opening and closing of the front cover 4. The present invention is not limited to this, and the image forming apparatus 1 may not require the movement of the image forming unit driving member 22 to be linked to the opening and closing of the front cover 4, for example, by moving the image forming unit driving member 22 through an operator's operation. The same applies to the second embodiment.

[0130] [3-7. Other embodiment 7] Furthermore, in the second embodiment described above, the image forming apparatus 101 has been described as moving the head holder 12h up or down in conjunction with the opening and closing of the front cover 4 to move it closer to or away from the image forming unit 10. However, the present invention is not limited to this, and the image forming apparatus 101 does not need to move the head holder 12h in conjunction with the opening and closing of the front cover 4; for example, the head holder 12h may be moved by an operator's operation.

[0131] [3-8. Other embodiment 8] Furthermore, in the first embodiment described above, the image forming apparatus 1 has been described as having the locking portion 10a of the image forming unit 10 in the shape of an approximately isosceles triangle. However, the present invention is not limited to this, and the image forming apparatus 1 may have the locking portion 10a in various other shapes as long as it protrudes from the upper end surface 10u of the image forming unit 10. The same applies to the second embodiment.

[0132] [3-9. Other Embodiment 9] Furthermore, in the above-described embodiment, the present invention has been described as being applied to the image forming apparatus 1 or 101 to which the image forming unit 10, which is a detachable unit, is detachable. However, the present invention is not limited to this, and the present invention may also be applied to the image forming apparatus 1 or 101 to which various other detachable members such as the photosensitive drum 13, the transfer unit 14, the fixing unit 17, and the toner cartridge are detachably attached to the image forming apparatus 1 or 101.

[0133] [3-10. Other Embodiments 10] Furthermore, in the first embodiment described above, the image forming apparatus 1 applies the load Ps, the climbing load Po, and the load Pw to the image forming unit 10 by changing the load applied from the lock lever lock portion 30b of the lock lever 30 to the lock portion 10a of the image forming unit 10. The present invention is not limited to this, and the image forming apparatus 1 may apply the load Ps, the climbing load Po, and the load Pw to the image forming unit 10 by various other forces such as pressure, frictional force, magnetic force, and gravity. The same applies to the second embodiment.

[0134] [3-11. Other Embodiments 11] Furthermore, in the first embodiment described above, the image forming apparatus 1 has been described as changing the load applied from the lock lever lock portion 30b of the lock lever 30 to the lock portion 10a of the image forming unit 10 depending on the compression state of the spring 34. The present invention is not limited to this, and the image forming apparatus 1 may change the load applied from the lock lever lock portion 30b of the lock lever 30 to the lock portion 10a of the image forming unit 10 using various other members such as a magnet, an electromagnetic clutch, a weight, or a damper instead of the spring 34. The same applies to the second embodiment.

[0135] [3-12. Other Embodiments 12] Furthermore, in the above-described embodiment, the present invention has been described as being applied to the image forming apparatus 1, which is a monochrome printer that has one image forming unit 10 corresponding to the color black and performs monochrome printing. However, the present invention is not limited to this, and may be applied to various image forming apparatuses, such as an image forming apparatus that is a color printer that has four image forming units corresponding to the colors yellow, magenta, cyan, and black and performs color printing, or an image forming apparatus that has three or less or five or more image forming units.

[0136] [3-13. Other Embodiments 13] Furthermore, in the above-described embodiment, the present invention has been described as being applied to a printer, but the present invention is not limited to this and may be applied to various devices that perform various image processing, such as facsimiles, MFPs (Multifunction Printers), copiers, etc.

[0137] [3-14. Other Embodiments 14] Furthermore, the present invention is not limited to the above-described embodiments and other embodiments. That is, the scope of application of the present invention also extends to embodiments in which the above-described embodiments are combined in part or in whole with any of the above-described other embodiments. The scope of application of the present invention also extends to embodiments in which part of the configuration described in any of the above-described embodiments and other embodiments is extracted and used as part of the configuration of any of the above-described embodiments and other embodiments, or in which part of the extracted configuration is added to any of the above-described embodiments.

[0138] [3-15. Other Embodiments 15] Furthermore, in the first embodiment described above, the image forming apparatus 1 is configured as an image forming apparatus using the image forming unit 10 as a detachable unit, the lock lever 30 as a load supplying member, and the load changing unit 36 ​​as a load changing unit. However, the present invention is not limited to this, and the image forming apparatus may be configured using a detachable unit, a load supplying member, and a load changing unit having various other configurations. [Industrial Applicability]

[0139] The present invention can be used not only in a computer that causes a printer to print an image, but also in various electronic devices that perform various image-related processes, such as an image scanner, a facsimile machine, or a copying machine. [Explanation of symbols]

[0140] 1, 101...image forming device, 2...device housing, 2u...top surface of device housing, 2b...rear surface of device housing, 2r...right surface of device housing, 2l...left surface of device housing, 3...image forming unit insertion / removal opening, 4...front cover, 4a...slide lever contact portion, 8R, 108R...right frame, 8L...left frame, 8a...guide post, 9R...right guide frame, 9L...left guide frame, 9Sh...horizontal surface, 9Ss...inclined surface, 10...image forming unit, 10a...lock portion, 1 0u...top surface, 10ar...resistance surface when removed, 10aa...resistance surface when installed, 12...head unit, 13...photosensitive drum, 14...transfer unit, 15...transfer roller, 16...paper tray, 17...fixing unit, 18...heating roller, 19...pressure roller, 20...paper exit, 21...paper stacker section, 22...image forming unit drive member, 23...urging spring, 24R, 124R, 224R...right side drive mechanism, 24L, 124L...left side drive mechanism, 26, 126...slide Lever, 26g...guide post sliding groove, 26a...front cover abutment portion, 26b...link lever abutment portion, 26d...drive member sliding groove, 26S1...left side flat surface, 26S2...inclined surface, 26S3...right side flat surface, 28...tension lever, 28a...fulcrum, 28b...inclined rib, 30, 130...lock lever, 30a...rotation fulcrum, 30b, 130b...lock lever lock portion, 32...link lever, 32a...fulcrum, 32b...slide lever abutment portion, 32c...inclined rib abutment Contact portion, 34, 35...spring, 36, 136...load changing portion, 12d...LED head, 12h...head holder, 12hh, 12hv...post, 41...slide piece, 42...spring, 108a...guide groove, 108av...upper and lower groove portion, 108ah...front and rear groove portion, 126i...slide piece abutment inclined surface, 126c...hole portion, 50, 56...spring holding member, 52...tension lever, 53...spring, 54...tension lever holding member, 58...stopper.

Claims

1. a detachable unit that can be inserted into and removed from the device body; a load supplying member that applies a load to the detachable unit; a load changing unit that applies a first load to the detachable unit by the load supply member when the detachable unit passes a predetermined position during insertion or removal of the detachable unit from the device body, applies a second load to the detachable unit by the load supply member at a position where the detachable unit is attached to the device body, and applies a third load larger than the second load to the detachable unit by the load supply member after the detachable unit is attached to the device body; An image forming apparatus having the same.

2. The device further includes a cover that can be opened and closed relative to the device body, The load changing unit With the cover in an open state, the load supply member applies the second load to the detachable unit at a position where the detachable unit is attached to the device body, and with the cover in a closed state, the load supply member applies the third load to the detachable unit at a position where the detachable unit has been attached to the device body. The image forming apparatus according to claim 1 .

3. The load changing unit The load is moved in conjunction with the opening and closing of the cover, and when the cover transitions from a closed state to an open state, the load is switched from the third load to the second load. The image forming apparatus according to claim 2 .

4. The load changing unit a lock lever that abuts against the detachable unit and applies a load; a biasing member that changes a biasing force that presses the lock lever against the detachable unit in conjunction with opening and closing of the cover; The image forming apparatus according to claim 2 , further comprising:

5. The first load is greater than the second load. The image forming apparatus according to claim 1 .

6. The device further includes a cover that can be opened and closed relative to the device body, the detachable unit includes an image forming unit, The load changing unit a moving mechanism that moves a first member closer to the image forming unit when the cover is closed and moves the first member away from the image forming unit when the cover is open; The image forming apparatus according to claim 1 .

7. The moving mechanism includes: A driving force is transmitted to the image forming unit when the cover is closed, and the transmission of the driving force is released when the cover is open. The image forming apparatus according to claim 6 .

8. The moving mechanism includes: When the cover is in a closed state, the exposure unit is brought close to the image forming unit, and when the cover is in an open state, the exposure unit is separated from the image forming unit. The image forming apparatus according to claim 6 .

9. The load changing unit When image formation is possible, the load supply member applies the third load to the detachable unit. The image forming apparatus according to claim 1 .

10. a detachable unit that can be inserted into and removed from the device body; a load supplying member that applies a load to the detachable unit; a load changing unit that applies a first load to the detachable unit by the load supply member when the detachable unit passes a predetermined position during insertion or removal of the detachable unit from the apparatus main body, applies a second load to the detachable unit by the load supply member when the detachable unit is attached to the apparatus main body, and applies a third load larger than the second load to the detachable unit by the load supply member when image formation is possible; An image forming apparatus having the same.

Images