Image forming apparatus

Abstract

The laser shutter and interlock switch operate regardless of the twisting of the opening / closing cover, and the interlock switch can be positioned more freely without requiring a complex mechanism. [Solution] The device comprises a laser shutter 2S having a positioning projection 2S5 for blocking laser light, a door 20 that can be opened and closed relative to the main body 1A of the device, an opening / closing detection member 90 that operates in accordance with the opening and closing operation of the door 20, and an interlock switch 91 having an engaging portion 92a for turning a high-voltage power supply on or off. The opening / closing detection member 90 has an engaging portion 90e that engages with the positioning projection 2S5 of the laser shutter 2S and a projection 90c that engages with the engaging portion 92a of the interlock switch 91. The positioning projection 2S5 of the laser shutter 2S is located on one side of the scanner unit 2, and the engaging portion 92a of the interlock switch 91 is located opposite one side of the scanner unit 2.

Description

Technical Field

[0001] The present invention relates to an image forming apparatus that forms an image on a recording material.

Background Art

[0002] Image forming apparatuses such as printers, copiers, and multifunction peripherals are provided with an opening / closing cover (opening / closing member) that can be opened and closed with respect to the apparatus main body for supplying toner and processing paper jams (hereinafter referred to as jam processing). The image forming apparatus is configured such that when the opening / closing cover is opened, the laser light is not irradiated from the light source to the outside of the apparatus and the high-voltage power supply is turned off. For this reason, the image forming apparatus is provided with a laser shutter member, an interlock switch for turning on and off the high-voltage power supply, and a link mechanism. For example, Patent Document 1 proposes providing an engaging portion for operating the laser shutter and turning on the interlock switch on the opening / closing cover. Protrusion shapes for operating the laser shutter and protrusion shapes for turning on the interlock switch are provided on the opening / closing cover, and these directly operate by the opening / closing operation of the opening / closing cover. Also, for example, Patent Document 2 proposes a configuration in which the interlock switch is arranged on a switch holder that can swing, and the laser shutter is also operated by the switch holder.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, conventional image forming apparatuses have the following challenges. For example, in configurations with protruding shapes, the protrusions on the opening / closing cover are divided into those for the laser shutter and those for the interlock switch. Therefore, if the opening / closing cover is unintentionally twisted during operation, there is a risk that a difference may occur between the operation of the laser shutter and the on-timing of the interlock switch. For example, if a specific sequence of operations is required, such as opening the laser shutter after the interlock switch is turned on, it is necessary to increase the torsional rigidity of the opening / closing cover to prevent a difference between the operation of the laser shutter and the on-timing of the interlock switch. Furthermore, in configurations using a switch holder, the interlock switch is turned on when the two protruding shapes of the opening / closing cover and the upper unit containing the toner are aligned. In such configurations, in order to accurately turn the interlock switch on and off, these mechanisms must be simplified as much as possible. To achieve this, the position of the interlock switch must naturally be near the product exterior and close to the opening / closing cover, which may impose constraints on the location where the switch can be placed.

[0005] This invention was made under such circumstances, and aims to enable the laser shutter and interlock switch to operate regardless of the twisting of the opening / closing cover, while also increasing the degree of freedom in the placement of the interlock switch without requiring a complex mechanism. [Means for solving the problem]

[0006] To solve the above-mentioned problems, the present invention has the following configuration.

[0007] (1) An image forming apparatus comprising: a scanner unit that irradiates laser light in accordance with an image signal; a photoreceptor on which a latent image is formed by the laser light irradiated from the scanner unit, wherein the apparatus further comprises: a laser shutter having a first engaging portion for blocking the laser light; an opening / closing member that can be opened and closed relative to the main body of the apparatus; an opening / closing detection member that operates in accordance with the opening / closing operation of the opening / closing member; and an interlock switch having a second engaging portion for turning a high-voltage power supply on or off, wherein the opening / closing detection member has a third engaging portion that engages with the first engaging portion of the laser shutter and a fourth engaging portion that engages with the second engaging portion of the interlock switch, the first engaging portion of the laser shutter is located on one side of the scanner unit, and the second engaging portion of the interlock switch is located opposite the one side of the scanner unit. [Effects of the Invention]

[0008] According to the present invention, the laser shutter and interlock switch operate regardless of the twisting of the opening / closing cover, and the degree of freedom in the placement of the interlock switch can be increased without requiring a complex mechanism. [Brief explanation of the drawing]

[0009] [Figure 1] Diagram illustrating the overall configuration of the printer in Example 1. [Figure 2] Diagram showing the printer in the open position of the door in Example 1. [Figure 3] Diagram illustrating the laser shutter of Example 1. [Figure 4] A bottom view illustrating the laser shutter and scanner of Example 1. [Figure 5] Cross-sectional view illustrating the laser shutter and scanner of Example 1. [Figure 6] Diagram illustrating the case where the laser shutter in Example 1 blocks the laser, and diagram illustrating the case where the laser shutter transmits the laser. [Figure 7] Diagram showing the opening and closing of the door and the operation of the laser shutter in Example 1. [Figure 8] Perspective view and front view showing the installation of the interlock switch in Example 1 [Figure 9] Diagram showing the opening and closing of the door and the on / off state of the interlock switch in Example 1. [Figure 10] A diagram showing the correlated positions of the laser shutter and interlock switch in Example 1, and an explanatory diagram showing the mounting position of the interlock switch. [Figure 11] This diagram illustrates the opening and closing trajectory of the door in Example 1 and the direction of movement of the opening / closing detection member. [Figure 12] Diagram illustrating the mounting position of the interlock switch in Example 2 [Modes for carrying out the invention]

[0010] The embodiments for carrying out this invention will be described in detail below with reference to the drawings, based on examples. However, the dimensions, materials, shapes, and relative arrangements of the components described in these embodiments should be appropriately modified depending on the configuration of the device to which the invention is applied and various conditions. In other words, the scope of this invention is not intended to be limited to the following embodiments. [Examples]

[0011] [Overall structure] The printer 1 as an image forming apparatus will be described using Figure 1. Figure 1 is a diagram illustrating the overall configuration of the printer 1 of Embodiment 1. The printer 1 is an electrophotographic color laser beam printer that forms an image on a sheet S (recording material). The printer 1 has a main body (housing) 1A, a scanner unit (exposure device) 2, a control unit 3, and a door 20 as an opening / closing member that can be opened and closed relative to the main body 1A. The printer 1 has a sheet feeding unit 30, a transfer unit 40, a tray unit (tray unit, moving unit, support unit) 50, and a fixing device 80. The part including the main body 1A and the door 20 can also be called the main frame 100. The main frame 100 includes the exterior of the printer 1. The main body 1A houses the scanner unit 2, the control unit 3, the sheet feeding unit 30, the transfer unit 40, the tray unit 50, and the fixing device 80. The sheet feeding unit 30 has a loading tray 31 for loading the sheet S and a supply roller 32. The loading tray 31 can be pulled out towards the door 20 to replenish the seats S.

[0012] The tray unit 50 has a tray (support member, drawer) 51 and cartridges PY, PM, PC, and PK. The tray 51 has a tray handle 52. The cartridges PY, PM, PC, and PK are removablely mounted on the tray 51. Each of the cartridges PY, PM, PC, and PK can be independently attached to and detached from the tray 51 relative to the others. The cartridges PY, PM, PC, and PK contain yellow (Y), magenta (M), cyan (C), and black (K) toner (developer), respectively. The cartridges PY, PM, PC, and PK have the same configuration except for the color of the toner they contain. Therefore, the configuration and operation of one of the cartridges PY, PM, PC, or PK may be described, and the descriptions of the others may be omitted. Also, when there is no need to distinguish between the cartridges PY, PM, PC, and PK, they may simply be referred to as cartridge P. The tray unit 50 can be said to have multiple cartridges P and a tray 51 on which the multiple cartridges P are removablely mounted.

[0013] In Example 1, the tray unit 50 has a plurality of photosensitive drums (image carriers, photoreceptors) 61, a plurality of charging rollers 62 (charging members), and a plurality of developing rollers (developer carriers, developing members) 71. Specifically, the tray unit 50 has four photosensitive drums 61, four charging rollers 62, and four developing rollers 71. The rotational axis directions of the photosensitive drum 61, the developing roller 71, and the charging roller 62 are parallel. The portion for forming the black (K) image is called the black station (first station), the photosensitive drum 61 of the first station is called the first photosensitive drum, the developing roller 71 is called the first developing roller, and the charging roller 62 is called the first charging roller. The portion for forming the cyan (C) image is called the cyan station (second station), the photosensitive drum 61 of the second station is called the second photosensitive drum, the developing roller 71 is called the second developing roller, and the charging roller 62 is called the second charging roller. The portion for forming the magenta (M) image is called the magenta station (third station), the photosensitive drum 61 of the third station is called the third photosensitive drum, the developing roller 71 is called the third developing roller, and the charging roller 62 is called the third charging roller. The portion for forming the yellow (Y) image is called the yellow station (fourth station), the photosensitive drum 61 of the fourth station is called the fourth photosensitive drum, the developing roller 71 is called the fourth developing roller, and the charging roller 62 is called the fourth charging roller.

[0014] The cartridge PK is mounted on the black station, the cartridge PC is mounted on the cyan station, the cartridge PM is mounted on the magenta station, and the cartridge PY is mounted on the yellow station, respectively. In Example 1, the cartridge PK is called the first cartridge, the cartridge PC is called the second cartridge, the cartridge PM is called the third cartridge, and the cartridge PY is called the fourth cartridge. The numbers such as first, second, third, and fourth are used for convenience in explanation. The photosensitive drum 61, the charging roller 62, and the developing roller 71 may be provided in either the cartridge P or the tray 51. In Example 1, the cartridge P has the photosensitive drum 61, the charging roller 62, and the developing roller 71.

[0015] The transfer unit 40 includes a belt 41, a primary transfer roller 42, a cleaning unit 43, a drive roller 46 that drives the belt 41, and a tension roller (driven roller) 47. The printer 1 is provided with an optical sensor 44 that detects the toner image (developer image) transferred onto the belt 41. The belt 41 is disposed below the photosensitive drum 61 and is capable of contacting the photosensitive drum 61 such that a primary transfer portion is formed between the belt 41 and the photosensitive drum 61. Further, the printer 1 has a secondary transfer roller 45 (transfer member) that contacts the belt 41 such that a secondary transfer portion is formed. The secondary transfer portion is formed between the belt 41 and the secondary transfer roller 45. The axial direction of rotation of the primary transfer roller 42, the axial direction of rotation of the drive roller 46, the axial direction of rotation of the tension roller 47, and the axial direction of rotation of the secondary transfer roller 45 are parallel. In front of the secondary transfer portion, a registration roller pair 4 is disposed. The fixing device 80 includes a fixing portion 81 and a flapper 5. The fixing portion 81 includes a heating portion (heating roller) including a heater and a pressing portion (pressing roller).

[0016] [Image forming operation] Using FIG. 1, the image forming operation of the printer 1 will be described. The control unit 3 of the printer 1 starts an image forming operation on the sheet S based on the image signal received from the external host device 400. The external host device 400 is, for example, a personal computer, an image reader, a facsimile machine, or the like.

[0017] When image formation on the sheet S is performed, a charging voltage is applied to the charging roller 62 and the photosensitive drum 61 rotates. A laser corresponding to the image information is irradiated from the scanner unit 2 onto the photosensitive drum 61, and the surface of the photosensitive drum 61 charged by the charging roller 62 is exposed. Thereby, an electrostatic latent image corresponding to the image information is formed on the surface of the photosensitive drum 61.

[0018] The developing roller 71 carries toner. A developing voltage is applied to the developing roller 71, and the electrostatic latent image formed on the photosensitive drum 61 is developed by the toner supplied from the developing roller 71, forming a toner image on the surface of the photosensitive drum 61. In Example 1, the developing roller 71 develops the electrostatic latent image while in contact with the photosensitive drum 61, but the developing roller 71 may develop the electrostatic latent image with a gap between the developing roller 71 and the photosensitive drum 61.

[0019] When a full-color image is formed, toner images of each color are formed on each photosensitive drum 61. The toner images formed on each photosensitive drum 61 are transferred onto the belt 41 by the primary transfer roller 42 in the primary transfer section and transported toward the secondary transfer section formed by the belt 41 and the secondary transfer roller 45.

[0020] Meanwhile, the main body 1A of the device has a transport path (first path, first transport path) 1c through which the sheet S heading toward the fixing device 80 passes. The door 20 also has a double-sided transport path (second path, second transport path) 20a through which the sheet S that has passed through the fixing device 80 passes. When the door 20 is closed, it covers the transport path 1c. When the door 20 is opened, the transport path 1c and the double-sided transport path 20a are exposed (see Figure 2).

[0021] In the sheet feeding unit 30, one sheet S is separated and fed at a predetermined timing by the supply roller 32 from among the multiple sheets S loaded on the loading tray 31, and is transported through the transport path 1c toward the secondary transfer unit and the fixing device 80. In the secondary transfer unit, the toner image is transferred from the belt 41 to the sheet S. Toner that was not transferred to the sheet S is removed from the belt 41 by a cleaning blade (cleaning member) 43A provided in the cleaning unit 43.

[0022] In the secondary transfer section, the sheet S onto which the toner image has been transferred is transported toward the fuser unit 80. In the fuser unit 80, the sheet S is heated and pressurized in the fuser unit 81, and the unfixed toner image is fixed to the sheet S. The sheet S with the fixed toner image is transported toward the flapper 5, which acts as a path switching unit. The flapper 5 is movable between an discharge position that guides the sheet S that has passed through the fuser unit 80 toward the discharge path 1d and a reversal position that guides it toward the reversal path 1e. When single-sided printing is performed, in which an image is formed on one side of the sheet S, the sheet S is guided toward the discharge path 1d by the flapper 5 and discharged into the discharge tray 1f formed on the upper part of the main body 1A of the device.

[0023] On the other hand, when double-sided printing is performed in which an image is printed on one side and the other side of the sheet S, the sheet S is guided to the reversal path 1e by the flapper 5. After the sheet S is guided to the reversal path 1e, the transport direction of the sheet S is reversed, and the sheet S is transported through the double-sided transport path 20a formed in the door 20 toward the secondary transfer section. In the secondary transfer section, after the toner image is transferred to the back side of the sheet S, the sheet S passes through the fuser 80, is guided to the discharge path 1d by the flapper 5, and is discharged into the discharge tray 1f of the main body 1A.

[0024] [Door opening / closing and operation of the opening / closing detection component] The opening and closing operation of the door 20 and the opening / closing detection member 90 will be explained using Figures 1 and 2. The door 20, which is attached to the main body 1A of the device, is movable between a closed position and an open position. The main body 1A of the device is provided with an opening 1A1 for inserting and removing the transfer unit 40 and the tray unit 50 and for jamming. As shown in Figure 1, when the door 20 is in the closed position (closed state of the door 20), the door 20 covers the opening 1A1. As shown in Figure 2, when the door 20 is in the open position (open state of the door 20), the opening 1A1 is exposed.

[0025] As shown in Figure 1, when the door 20 is in the closed position, the door 20 covers the fixing device 80 attached to the main body 1A of the device. More specifically, when the door 20 is in the closed position, the upper cover portion 20b of the door 20 is located above the fixing device 80. The upper cover portion 20b of the door 20 functions as part of the exterior.

[0026] The door 20 can move between an open position and a closed position while the fuser 80 is supported by the device body 1A. In other words, the door 20 moves from the closed position to the open position so as to move away from the fuser 80 supported by the device body 1A. Therefore, as shown in Figure 2, when the door 20 is in the open position, the door 20 is away from the fuser 80 supported by the device body 1A. When the door is in the open position, cartridge replacement, jam clearing (clearing paper jams), etc., can be performed. In Embodiment 1, there is one door to the device body 1A, and all operations can be performed by opening and closing a single door 20, making it easy for the user to understand and convenient.

[0027] The main body of the device 1A is provided with an opening / closing detection member 90 that is linked to the opening and closing of the door 20. The opening / closing detection member 90 is slidably positioned between a standby position and an operating position in conjunction with the opening and closing of the door 20, and is configured to engage with the door 20 at one end. The door 20 is provided with a projection member 21 (projection) for engaging with the opening / closing detection member 90, and the projection member 21 is integrally attached to the door 20. In Embodiment 1, the projection member 21 is separate from the door 20, but it may be integrally formed with the door 20 itself. In this way, if one end of the opening / closing detection member 90 is the engagement portion 90d, the projection member 21 of the door 20 is engaged with the engagement portion 90d when the door 20 is in the closed position.

[0028] In Figure 1, the door 20 is in the closed position, and at this time the opening / closing detection member 90 is in the operating position. When the door 20 is moved from this position toward the open position, the projection member 21 of the door 20 separates from the engaging portion 90d of the opening / closing detection member 90, i.e., the engagement is released. As a result, the opening / closing detection member 90 moves in the direction of arrow A in Figure 1 by an elastic member (not shown). In Figure 2, the opening / closing detection member 90 is in the standby position. The operation of the laser shutter and interlock switch in conjunction with the movement of the opening / closing detection member 90 will be explained in more detail below.

[0029] [Laser shutter operation] The scanner unit 2 is equipped with a laser shutter 2S. The laser shutter 2S is a component that prevents laser light from leaking outside the main unit 1A of the device, and is configured to close when the door 20 is open. Therefore, even if laser light is emitted from the scanner unit 2 while the door 20 is open due to, for example, a malfunction of the electrical circuit board, the laser shutter 2S blocks the laser light, preventing it from leaking outside the main unit 1A of the device.

[0030] Figure 3 shows a schematic perspective view of the laser shutter 2S of Embodiment 1. As shown in Figure 3, the laser shutter 2S consists of a rotation axis 2S1, a laser beam shielding wall 2S2, a rotation boss 2S3, a regulating wall 2S4, and a positioning projection 2S5 (first engagement part). Figure 4 shows a bottom view (view of the scanner unit 2 from the bottom side of the device body 1A) of the laser shutter 2S installed in the scanner unit 2, and Figure 5 shows a cross-sectional view. First, the center CL of the rotation axis 2S1 of the laser shutter 2S is located below the rotating polyhedron mirror 210 of the scanner unit 2, and is positioned on the bisector E of lasers 2K, 2C and 2M, 2Y incident from a semiconductor laser (not shown) onto the rotating polyhedron mirror 210. The direction of the rotation axis 2S1 is the Y direction, the direction of the rotation axis of the rotating polyhedron mirror 210 is the Z direction, and the direction perpendicular to the Y and Z directions is the X direction.

[0031] Next, the positional restrictions of the laser shutter 2S relative to the scanner unit 2 will be described. As shown in Figure 4, the X direction is restricted by the first restricting wall 201 and the second restricting wall 202 provided on the scanner unit 2, which restrict the rotation axis 2S1. The Y direction is restricted by the shielding wall 2S2 and the restricting wall 2S4 sandwiching the first restricting wall 201 and the second restricting wall 202. As shown in Figure 5, the Z direction is restricted by the third restricting wall 203 and the fourth restricting wall 204 provided on the scanner unit 2, and by the fifth restricting wall 205 and the sixth restricting wall 206, which are positioned opposite the third restricting wall 203 and the fourth restricting wall 204, respectively.

[0032] More specifically, on the side of the rotating shaft 2S1 where the shielding wall 2S2 is provided, movement in the Z direction is restricted by the third restricting wall 203 and the fifth restricting wall 205, which is provided opposite the third restricting wall 203. On the side of the rotating shaft 2S1 where the restricting wall 2S4 is provided, movement in the Z direction is restricted by the fourth restricting wall 204 and the sixth restricting wall 206, which is provided opposite the fourth restricting wall 204. In addition, clearances are provided between each restricting part to allow the laser shutter 2S to operate smoothly.

[0033] Next, the operation of the laser shutter 2S of Example 1 will be explained with reference to Figure 6. Figure 6(a) shows the positional relationship between the laser shutter 2S, lasers 2K, 2C, 2M, 2Y, and the rotating polyhedron mirror 210 when the door 20 is open. Figure 6(b) shows the positional relationship between the laser shutter 2S, lasers 2K, 2C, 2M, 2Y, and the rotating polyhedron mirror 210 when the door 20 is closed.

[0034] First, as shown in Figure 6(a), when the door 20 is open, the optical paths of lasers 2K, 2C, 2M, and 2Y from the semiconductor laser (not shown) to the rotating polyhedron mirror 210 are blocked by the shielding wall 2S2 to prevent the lasers 2K, 2C, 2M, and 2Y from leaking outside the scanner unit 2. At this time, as viewed from the side of the restricting wall 2S4, the laser shutter 2S rotates clockwise (hereinafter referred to as the CW direction), and the positioning projection 2S5 engages (contacts) with the engaging portion 90e of the opening / closing detection member 90 to maintain its position. As shown in Figure 6(b), when the door 20 is closed, as viewed from the side of the restricting wall 2S4, the laser shutter 2S rotates counterclockwise (hereinafter referred to as the CCW direction). As a result, the optical paths of lasers 2K, 2C, 2M, and 2Y from the semiconductor laser (not shown) to the rotating polyhedron mirror 210 are opened, and the electrostatic latent image described above can be formed.

[0035] Next, the position of the opening / closing detection member 90 and the orientation of the laser shutter 2S will be explained. In Figures 7(a) and 7(b), the door 20 is in the closed position and the opening / closing detection member 90 is in the operating position. At this time, the positioning projection 2S5 of the laser shutter 2S engages (contacts) with the engaging portion 90e (third engaging portion) of the opening / closing detection member 90, and the laser shutter 2S is in the state shown in Figure 6(b). Note that the state in which the shielding wall 2S2 of the laser shutter 2S is not in the laser optical path as shown in Figure 6(b) and does not shield the irradiated laser is described as "open". Lasers 2Y, 2M, 2C, and 2K can be irradiated from the scanner unit 2 to each photosensitive drum 61.

[0036] When the door 20 is moved from the state shown in Figure 7(a) toward the open position, it reaches the states shown in Figures 7(c) and (d). The positioning projection 2S5 of the laser shutter 2S moves (downward) along the slope 90a of the opening / closing detection member 90, rotates in the CW direction as described above, and maintains its posture by contacting a part 90b of the opening / closing detection member 90. At this time, the laser shutter 2S is in the state shown in Figure 6(a). Note that the state in which the shielding wall 2S2 of the laser shutter 2S is in the optical path of the laser as shown in Figure 6(a) and shields the irradiated laser is described as "closed". Furthermore, in the states shown in Figures 7(e) and (f) when the door 20 is moved to the open position, the opening / closing detection member 90 is restricted by the frame of the device body 1A (not shown) and enters a standby position. The laser shutter 2S continues to contact a part 90b of the opening / closing detection member 90 and maintains its posture.

[0037] The positioning projection 2S5 of the laser shutter 2S is located on the outside of the scanner unit 2 and is connected to the laser shielding wall 2S2 located inside the scanner unit 2 via a rotating shaft 2S1 (see Figures 4 and 5). In other words, the positioning projection 2S5, which acts as an engaging part for operating the laser shutter 2S, is rotatably supported on one side of the outside of the scanner unit 2 (see Figure 10(b)). Note that in Figure 7, for illustrative purposes, the shielding wall 2S2, which is actually inside the scanner unit 2, is also shown as a solid line.

[0038] Furthermore, in the configuration of Example 1, the laser shutter 2S rotates to irradiate / shield the laser, but the operation of the laser shutter 2S is not limited to rotation; it may also irradiate / shield the laser linearly. In this way, the laser shutter 2S can reliably shield lasers 2Y, 2M, 2C, and 2K regardless of the state in which the user opens the door 20.

[0039] [Interlock switch operation] As shown in Figure 8(a), the interlock switch 91 is immovably mounted to the frame of the device body 1A (not shown) via a switch holder 94. The interlock switch 91 is a switch for turning the high-voltage power supply on and off. A rotatable rotating member 92 is provided next to the interlock switch 91 and is biased in one direction by an elastic member 93. The rotating member 92 rotates by engaging with an open / close detection member 90. Figure 8(b) shows a front view of the interlock switch 91. When the door 20 (not shown) moves from the open position to the closed position, the rotating member 92 is pushed in the direction of arrow C in the figure and rotates in the CCW direction when viewed from the interlock switch 91 side. As a result, the arm 91a of the interlock switch 91 is displaced from the dotted line position to the solid line position, and the switch turns on. A bundle of wires 95 runs from the interlock switch 91 via a faston terminal 91b and is connected at the end of arrow B to a circuit board on which the circuit of the high-voltage power supply (not shown) is mounted.

[0040] Next, the position of the opening / closing detection member 90 and the on / off state of the interlock switch 91 will be explained. In Figures 9(a) and (b), the door 20 is in the closed position and the opening / closing detection member 90 is in the operating position. At this time, the engaging portion 92a (second engaging portion) of the rotating member 92 engages with the projection 90c (fourth engaging portion) of the opening / closing detection member 90, causing the rotating member 92 to rotate in the CCW direction when viewed from the interlock switch 91 side. At this time, the interlock switch 91 is on.

[0041] When the door 20 is moved from this state toward the open position, it reaches the state shown in Figures 9(c) and (d), and the rotating member 92 rotates in the CW direction as viewed from the interlock switch 91 side, due to the force from the elastic member 93 and the movement of the projection 90c of the opening / closing detection member 90. At this time, the interlock switch 91 is turned off. Furthermore, in the state shown in Figures 9(e) and (f) when the door 20 is moved to the open position, the opening / closing detection member 90 is restricted by the frame of the device body 1A (not shown) and enters a standby position. The engaging portion 92a of the rotating member 92 continues to be in contact with the projection 90c of the opening / closing detection member 90, and the posture of the rotating member 92 is maintained.

[0042] The opening / closing detection member 90 controls the on / off state of the interlock switch 91 via the rotating member 92, but the rotating member 92 merely changes the direction of force transmission from the opening / closing detection member 90. In a broader sense, the rotating member 92 can also be considered an engaging part that switches the interlock switch 91 on and off.

[0043] [Positional relationship between laser shutter and interlock switch] Figure 10(a) shows a perspective view illustrating the engagement portions of the laser shutter 2S, the interlock switch 91, and the open / close detection member 90 described above. The interlock switch 91 is installed near the scanner unit 2. The projection 90c and the engagement portion 90e of the open / close detection member 90 are formed from a single component. The projection 90c engages with the interlock switch 91 via the rotating member 92. The engagement portion 90e engages with the positioning projection 2S5 of the laser shutter 2S.

[0044] The opening / closing detection member 90 moves (slides) in the direction of arrow K (movement direction) between the positioning projection 2S5 of the laser shutter 2S and the interlock switch 91, switching between the operating position and the standby position. Therefore, the order of turning the interlock switch 91 on / off and the operation of the laser shutter 2S can be precisely determined. The engaging portion 90e is positioned on one side of the opening / closing detection member 90 in a direction perpendicular to the direction of arrow K, and the projection 90c is positioned on the other side of the opening / closing detection member 90 in a direction perpendicular to the direction of arrow K. The reaction force when turning on the interlock switch 91 and the reaction force that operates the laser shutter 2S act on both sides (90c, 90e) of the opening / closing detection member 90. Therefore, twisting of the opening / closing detection member 90 can be suppressed, and the sliding operation of the opening / closing detection member 90 becomes smooth.

[0045] Figure 10(b) shows the scanner unit 2 viewed from the side (the side facing the interlock switch 91), in other words, in the direction of the rotation axis 2S1 of the laser shutter 2S (hereinafter referred to as the rotation axis direction). When viewed in the rotation axis direction, the interlock switch 91 is located within the area of ​​one side of the scanner unit 2 where the positioning projection 2S5 of the laser shutter 2S is located (the shaded area SD in Figure 10(b)). However, it is not limited to this, and if a part of the engaging portion of the interlock switch 91 (including the rotating member 92) overlaps with one side (SD) of the scanner unit 2, the laser shutter 2S and the interlock switch 91 can be said to be in close proximity. And it can be said that the interlock switch 91 is positioned opposite one side of the scanner unit 2 (see Figure 10(a)).

[0046] In Embodiment 1, as shown in Figure 11, the projection member 21 of the door 20 is configured so as not to interfere with the fixing device 80 during the opening and closing of the door 20 in the opening and closing trajectory 20L, which is the trajectory followed by the projection member 21 during the opening and closing operation of the door 20. This prevents the main body size from becoming unnecessarily large. In Embodiment 1, the door 20 is the front of the product, and when viewed from the door 20 side (opening / closing member side, front side), the projection member 21 is located further back in the product than the fixing device 80. This makes it possible to reduce the size of the opening / closing detection member 90, and since the opening / closing detection member 90 does not need to be an interlocking mechanism of multiple parts via the fixing device 80, the accuracy of the operation is increased without complicating the mechanism, and costs are kept low.

[0047] Furthermore, when the projection member 21 of the door 20 and the opening / closing detection member 90 engage, the pushing direction of the projection member 21 (arrow M) (tangential direction of the opening / closing trajectory 20L of the door 20) and the sliding direction of the opening / closing detection member 90 (arrow N) are approximately parallel. This improves the efficiency of force transmission, thereby suppressing loss of movement and twisting due to deformation of the opening / closing detection member 90. As a result, even if the interlock switch 91 and laser shutter 2S are located in recessed positions within the product, it is possible to accurately operate the interlock switch 91 and laser shutter 2S from the door 20.

[0048] As explained above, there is only one door 20, and the opening / closing detection member 90 engages with the door 20 at one point. Therefore, even if the door 20 twists, the positional relationship between the opening / closing detection member 90 and the engagement point of the interlock switch 91 / laser shutter 2S does not change, so the state of both engagement points can be reliably transitioned. In addition, since the opening / closing detection member 90 is a roughly rod-shaped sliding member, it is less likely to twist or bend in response to the movement of position caused by the opening and closing of the door 20. Therefore, even if the interlock switch 91 is located in a recessed area inside the product, it is possible to reliably switch it on and off.

[0049] As described above, according to Embodiment 1, the laser shutter and interlock switch operate regardless of the twisting of the opening / closing cover, and the degree of freedom in the placement of the interlock switch can be increased without requiring a complex mechanism. [Examples]

[0050] Example 2 will now be described. In Example 2, components similar to those described in Example 1 will be indicated using the same reference numerals as those used in Example 1. Furthermore, the description of components similar to those in Example 1 may be omitted.

[0051] [Interlock switch and open / close detection member] In Embodiment 2, the interlock switch 91A is configured to directly engage with the open / close detection member 90A. In Embodiment 1, a rotating member 92 was placed next to the interlock switch 91 to change the direction of force transmission from the open / close detection member 90, but in Embodiment 2, the force from the open / close detection member 90A is transmitted directly to the arm 91Aa of the interlock switch 91A.

[0052] Figure 12 shows a side view of the scanner unit 2 of Embodiment 2. Compared to Figure 10(b) of Embodiment 1, the position of the interlock switch 91A is as shown in Figure 12, with the operating direction of the arm 91Aa being vertical. The door 20 (not shown) is in the closed position, and the open / close detection member 90A is in the operating position. The engagement portion 90Ac between the open / close detection member 90A and the interlock switch 91A pushes in the arm 91Aa of the interlock switch 91A, and the interlock switch 91A is in the ON state. The faston terminal of the interlock switch 91A is designated as 91Ab.

[0053] The interlock switch 91A partially overlaps with the area on one side of the scanner unit 2 (the shaded area SD in Figure 12) where the positioning projection 2S5 of the laser shutter 2S is located. Even in this case, it can be said that the interlock switch 91A is positioned opposite one side of the scanner unit 2 (area SD). The rotating member 92 in Embodiment 1 has been removed, resulting in a simpler mechanism while still ensuring reliable operation of the laser shutter 2S / interlock switch 91A, which is preferable.

[0054] As described above, according to Embodiment 2, the laser shutter and interlock switch operate regardless of the twisting of the opening / closing cover, and the degree of freedom in the placement of the interlock switch can be increased without requiring a complex mechanism.

[0055] This embodiment includes the following configuration. (Composition 1) A scanner unit that emits laser light according to the image signal, A photoreceptor in which a latent image is formed by laser light emitted from the scanner unit, An image forming apparatus comprising, A laser shutter having a first engaging portion for blocking the laser light, An opening / closing member that can be opened and closed relative to the main body of the device, An opening / closing detection member that operates in accordance with the opening / closing operation of the opening / closing member, An interlock switch having a second engaging portion for turning a high-voltage power supply on or off, Equipped with, The opening / closing detection member has a third engaging portion that engages with the first engaging portion of the laser shutter, and a fourth engaging portion that engages with the second engaging portion of the interlock switch, The first engaging portion of the laser shutter is located on one side of the scanner unit, The second engaging portion of the interlock switch is positioned opposite to one side of the scanner unit. An image forming apparatus characterized by the following features. (Configuration 2) The opening / closing member is provided on the main body of the device and engages with the opening / closing detection member at one point. The image forming apparatus according to configuration 1, characterized in that it is a picture forming apparatus. (Composition 3) A developing member that develops the latent image formed on the photoreceptor and forms a developer image, A transfer member for transferring the developer image onto a recording material, A fixing device for fixing the unfixed developer image on the recording material, Equipped with, The opening / closing member is movable between a closed position and an open position and has a projection that engages with the opening / closing detection member. The aforementioned projection is located further back than the fixing device when the opening / closing member is in the closed position, as viewed from the opening / closing member side. An image forming apparatus according to configuration 1 or configuration 2, characterized by the above. (Composition 4) The opening / closing detection member is capable of sliding between an operating position when the opening / closing member is in the closed position and a standby position when the opening / closing member is in the open position. The direction of the sliding movement is parallel to the direction of movement of the opening / closing member when the projection of the opening / closing member engages with the opening / closing detection member. The image forming apparatus according to configuration 3, characterized in that it is a picture forming apparatus. (Composition 5) The opening / closing detection member slides between the laser shutter and the interlock switch. The image forming apparatus according to configuration 4, characterized in that... (Composition 6) The third engaging portion is provided on one side of the opening / closing detection member in a direction perpendicular to the direction of sliding movement, The fourth engaging portion is provided on the other side of the opening / closing detection member in a direction perpendicular to the direction of sliding movement. The image forming apparatus according to configuration 5, characterized by the features described herein. (Composition 7) The third engagement portion and the fourth engagement portion are formed from a single component. An image forming apparatus according to any one of configurations 1 to 6, characterized by the above. [Explanation of symbols]

[0056] 2 Scanner Units 2S Laser Shutter 2S5 Positioning protrusion 20 doors 90 Open / close detection member 90c protrusion 90e Engagement part 91 Interlock switch 92a Engagement part

Claims

1. A scanner unit that emits laser light according to the image signal, A photoreceptor in which a latent image is formed by laser light emitted from the scanner unit, An image forming apparatus comprising, A laser shutter having a first engaging portion for blocking the laser light, An opening / closing member that can be opened and closed relative to the main body of the device, An opening / closing detection member that operates in accordance with the opening / closing operation of the opening / closing member, An interlock switch having a second engaging portion for turning a high-voltage power supply on or off, Equipped with, The opening / closing detection member has a third engaging portion that engages with the first engaging portion of the laser shutter, and a fourth engaging portion that engages with the second engaging portion of the interlock switch, The first engaging portion of the laser shutter is located on one side of the scanner unit. The second engaging portion of the interlock switch is positioned opposite to one side of the scanner unit. An image forming apparatus characterized by the following features.

2. The opening / closing member is provided on the main body of the device and engages with the opening / closing detection member at one point. The image forming apparatus according to feature 1.

3. A developing member that develops the latent image formed on the photoreceptor and forms a developer image, A transfer member for transferring the developer image onto a recording material, A fixing device for fixing the unfixed developer image on the recording material, Equipped with, The opening / closing member is movable between a closed position and an open position and has a projection that engages with the opening / closing detection member. The aforementioned projection is located further back than the fixing device when the opening / closing member is in the closed position, as viewed from the opening / closing member side. The image forming apparatus according to feature 1.

4. The opening / closing detection member is capable of sliding between an operating position when the opening / closing member is in the closed position and a standby position when the opening / closing member is in the open position. The direction of the sliding movement is parallel to the direction of movement of the opening / closing member when the projection of the opening / closing member engages with the opening / closing detection member. The image forming apparatus according to feature 3.

5. The opening / closing detection member slides between the laser shutter and the interlock switch. The image forming apparatus according to feature 4.

6. The third engaging portion is provided on one side of the opening / closing detection member in a direction perpendicular to the direction of sliding movement, The fourth engaging portion is provided on the other side of the opening / closing detection member in a direction perpendicular to the direction of sliding movement. The image forming apparatus according to feature 5.

7. The third engagement portion and the fourth engagement portion are formed from a single component. The image forming apparatus according to feature 1.

Images