JP2000280571A - Image forming device - Google Patents

Abstract

(57) [Problem] To provide an image forming apparatus capable of easily accessing a substrate and attaching / detaching the substrate. SOLUTION: A storage portion of a process cartridge 20, a fixing unit 40 or a laser scanner unit 50 has a first opening formed on a bottom surface of the storage portion, a base plate for opening and closing the first opening, and a substrate 104. And a lid 92 for opening and closing the second opening. The substrate 104 can be attached and detached via the first opening. I have.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a laser beam printer and, more particularly, to an image forming apparatus capable of easily accessing a substrate and attaching / detaching the substrate.

[0002]

2. Description of the Related Art There is known a laser beam printer which scans a photosensitive drum with a laser beam to form an electrostatic latent image and transfers an image elicited by toner onto a sheet for printing. In such a printer, a sheet cassette for storing a relatively large amount of sheets is detachably stored in a lower portion of the printer. Further, a metal base plate is provided above the paper feed cassette, and a scanner for irradiating a laser beam, a developing / transfer mechanism including the photosensitive drum, and a toner transferred onto paper are further provided above the base plate. A fixing mechanism for fixing the image is provided.

[0003]

In the printer constructed as described above, an electronic board such as a control board is mounted on the base plate from above so that the base plate can be effectively used as a shield plate. There is. However, in this case, unless the scanner, the developing / transfer mechanism, and the fixing mechanism located above the substrate are removed, the substrate cannot be accessed or the substrate cannot be detached.

An object of the present invention is to provide an image forming apparatus capable of easily accessing a substrate and attaching / detaching the substrate.

[0005]

According to the first aspect of the present invention, there is provided an image forming means for forming a predetermined image.
50), a storage section for storing the image forming means (20, 40, 50), and a substrate (104) disposed below the image forming means (20, 40, 50) and stored in the storage section. A first opening formed on a bottom surface of the storage, and a first lid configured to open and close the first opening;
And a second opening for exposing a part of the substrate (104), and a second lid (92) for opening and closing the second opening, and are provided through the first opening. The substrate (104) can be attached and detached.

In the present invention, the substrate (104) can be attached and detached by detaching the first lid (101), so that the substrate (104) can be removed without removing the image forming means (20, 40, 50). ) Can be attached and detached. Also, the substrate (10) can be removed simply by removing the second lid (92).
Part of 4) can be exposed.

[0007] In the printer according to the first aspect of the present invention, the component (91) for the substrate (104) is attached to the exposed portion of the substrate (104) exposed through the second opening. The connector (91) may be detachable via the second opening by disposing a connector for detachability and opening the second lid (92).

According to a third aspect of the present invention, there is provided an image forming means (20, 40, 50) for forming a predetermined image, an image forming means accommodating section for accommodating the image forming means (20, 40, 50), A substrate (104) arranged below the image forming means (20, 40, 50) and accommodated in the accommodating section, and a paper feed cassette (20) provided below the image forming means accommodating section (20, 40, 50). And 10) a cassette storage section (100) for detachably storing therein, wherein the image forming means storage section has a first opening formed on the bottom surface of the image forming means storage section,
A first lid (101) for opening and closing the first opening is provided, the substrate (104) is detachable via the first opening, and the first lid (101) is Paper cassette (1
It is characterized in that it can be attached and detached via the cassette accommodating section (100) in a state where 0) is removed.

According to the present invention, the first lid (101) can be attached and detached via the cassette housing (100).
The substrate (10) is removed by removing the first lid (101).
4) can be attached and detached, so that the image forming means (2)
0, 40, 50) without removing the substrate (104).
Can be attached and detached.

[0010] In the image forming apparatus according to claim 3,
A guide (15) for slidably supporting the sheet cassette (10) in the cassette storage portion (100).
Are provided, and a vertical gap secured between the upper end of the guide (15) and the bottom surface of the image forming means housing section is provided.
The first lid (101) may be detachable.

According to a third aspect of the present invention, in the image forming apparatus according to the fifth aspect, the substrate mounting member (103) is provided in the image forming means housing portion so as to face the first lid portion (101).
May be provided, and the substrate (104) may be sandwiched and fixed between the substrate mounting member (103) and the first lid (101).

In this case, the substrate (104) can be removed simply by removing the first lid (101).

The image forming apparatus according to claim 5,
The side surfaces of the image forming means housing portion and the cassette housing portion (10) extending in the direction along the mounting / removing direction of the paper feed cassette (10) may be connected to a common plate-like member (16). ) And a substrate mounting member (103)
May be supported via a plate-like member (16).

In the image forming apparatus according to the fifth or sixth aspect, as in the seventh aspect, the first lid portion (101) is fixed via a screw (102) which is screwed to the substrate mounting member (103). Then, the substrate (104) may be fixed by passing a screw (102) through the substrate (104).

In this case, the screw (102) is fastened to the substrate (10) together with the first lid (101).
4) can be fixed.

In the image forming apparatus according to any one of claims 3 to 7, the first cover (1)
01) and a grounding point in the image forming means accommodating portion, a lead wire for connecting the first lid portion (101) to the ground is connected, and the first lid portion (101) is connected with the lead wire. ) May be set so that the length of the lead wire can be removed.

In this case, there is no possibility that the connection of the lead wires will be incomplete when the first cover (101) is attached or detached.

The image forming apparatus according to any one of claims 1 to 8, wherein the substrate (104) is provided as described in (9).
May be used as a control board (104a) for controlling each part of the apparatus.

The image forming apparatus according to any one of claims 3 to 9, wherein the second opening for exposing a part of the substrate (104) is provided in the image forming means housing section. , A second lid (92) for opening and closing the second opening.

In this case, a part of the substrate (104) can be exposed by removing the second lid (92) without removing the first lid (101).

In order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are added in parentheses, but the present invention is not limited to the illustrated embodiment.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the image forming apparatus of the present invention is applied to a laser beam printer will be described below with reference to FIGS.

FIG. 1 is a side view of the laser beam printer, FIG. 2 is a rear view of the laser beam printer as viewed from the direction of line II-II in FIG. 1, and FIG. 3 is a laser beam as viewed from the direction of line III-III in FIG. FIG. 4 is a top view of the printer, FIG. 4 is a perspective view of the laser beam printer, and FIG. 5 is a sectional view of the laser beam printer.

As shown in FIGS. 1 to 5, a cassette storage unit 100 is provided below the laser beam printer 1, and a paper cassette 10 for storing stacked sheets is attached to and detached from the cassette storage unit 100. Stored as possible. By pulling out the paper feed cassette 10 through the handle 13 in the direction of arrow P (in front of the printer 1), the paper feed cassette 10 can be taken out. The paper feed cassette 10 is provided with a paper pressing plate (not shown) urged upward by a pressing spring (not shown), and the uppermost layer of paper stacked on the paper pressing plate is printed by the printer 1. The sheet is separated and fed by the action of the separation pad 15 by the action of the separation pad 15.

As shown in FIG. 2, on both sides (left and right sides in FIG. 2) of the laser beam printer 1, there are provided frames 16 extending in the vertical direction of the printer 1, and the lower ends of the frames 16 on both sides are provided. On the sides, cassette guides 15 for supporting the paper feed cassette 10 are attached. A rubber leg 17 is attached to the lower end of the cassette guide 15, and thereby the entire printer 1 is supported.

As shown in FIG. 1 to FIG. 3 and FIG. 5, an iron base plate 101 for vertically partitioning the printer 1 is provided immediately above the cassette housing section 100.

The process cartridge 20 is disposed above the base plate 101 (FIG. 5). The process cartridge 20, like the paper feed cassette 10, is also detachable, and is pulled out in the direction of arrow Q when replacing toner.
The process cartridge 20 includes a photosensitive drum 21 that transfers toner by contacting a sheet, a transfer roller 22 that faces the photosensitive drum 21, and a scorotron type that generates corona discharge and charges the surface of the photosensitive drum 21 to a positive potential. Cartridge 20 </ b> A having a charger 28, a developer chamber 24 in which toner is accumulated, a developing roller 25 supplying toner to the photosensitive drum 21, and a developing cartridge including a supply roller 27 supplying toner to the developing roller 25 20B. The developer chamber 24 is provided with an agitator 24a for stirring the toner.

The photoreceptor cartridge 20A and the developing cartridge 20B can be disassembled from each other. However, when the process cartridge 20 is removed from the main body of the printer 1, they are pulled out in an integrated state. A cover 33 whose lower end is rotatably attached to a rotation shaft 33a is provided on the front of the printer 1.
By opening the front of the printer 1 by rotating the printer 1 clockwise, the process cartridge 20 can be attached and detached.

As shown in FIG. 5, a pair of registration rollers 31 and 32 are rotatably mounted between the process cartridge 20 and the sheet cassette 10.

Above the process cartridge 20, a laser generator (not shown) for emitting a laser beam, a polygon mirror (hexahedral mirror) 41, a lens 42, a reflection mirror 43, a reflection mirror 44, and a lens 45, which are rotationally driven, are provided. Scanner unit 4 including a reflection mirror 46
0 is attached. As shown in FIG. 5, the laser beam L oscillated by the polygon mirror 41 is irradiated on the photosensitive drum 21 via the lens 42, the reflection mirrors 43 and 44, the lens 45 and the reflection mirror 46. An electrostatic latent image is formed on the surface.

On the left side of the process cartridge 20, a fixing unit 50 for fixing toner on paper is provided. The fixing unit 50 includes a heating roller 51 for heating and melting the toner on the transferred sheet, a pressing roller 52 disposed opposite to the heating roller 51, and pressing the fed sheet toward the heating roller 51. , A pair of transport rollers 53 and 54.

In FIG. 5, a shooter 61 for reversing the direction of the sheet as required is provided to the left of the transport rollers 53 and 54 (toward the back of the printer 1). In FIG. 5, the paper conveyed along the shooter 61 is supported on the right side of the rotation shaft 62 (in the front direction of the printer 1) while sandwiching the paper from above and below. A pair of discharge rollers 72 and 73 for discharging to the formed discharge tray 70 are attached.

As shown in FIG. 1 to FIG.
A cover 82 that covers a part of the paper discharge tray 70 is attached above the paper tray 70. The cover 82 protrudes above the sheet discharge tray 70 at the upper and lower portions of the tray 70 in FIG.

Next, the sheet feeding operation will be described.
When the paper feed roller 14 is rotated at a predetermined timing, the paper is discharged from the paper feed cassette 10 one by one. The sheet is inverted by the action of the guide 35, and after the position of the leading end is adjusted by the registration rollers 31 and 32, the sheet is conveyed between the photosensitive drum 21 and the transfer roller 22.

On the other hand, on the surface of the photosensitive drum 21 charged by the charger 28, a laser scanner unit 40 is provided.
The laser beam emitted from the device is irradiated to form an electrostatic latent image. The electrostatic latent image on the photosensitive drum 21 is
, The supply roller 27 and the developing roller 25
Makes the electrostatic latent image visible, and the toner image is transferred to a sheet passing between the photosensitive drum 21 and the transfer roller 22.

The sheet on which the toner image has been transferred next passes between the heating roller 51 and the pressing roller 52. At this time, heat and pressure are applied to the toner image on the sheet, so that the toner image is transferred onto the sheet. Be established.

Further, the paper passes between the transport rollers 53 and 54 and is transported along the chute 61, and then the printing surface is directed downward (face / face) between the paper output rollers 63 and 64 to the paper output tray 70. Drained down). When the shooter 61 is open (indicated by a dotted line in FIG. 5), the paper is discharged to the back side of the printer 1 with the printing surface facing up (face-up), as described later. .

FIG. 6 is a bottom view of the printer 1 with the sheet cassette 10 removed. In FIG. 6,
The arrangement positions of various substrates housed in the printer 1 are also illustrated.

As shown in FIGS. 2, 5 and 6, the above-mentioned base plate 101 is formed with a screw mounting portion 101a which is formed in a shape depressed upward.
The base plate 101 is attached to a resin-made attachment member 103, a folded portion 94 of the shield case SC (FIG. 5), and the like via a screw 102 penetrating the screw attachment portion 101a. As shown in FIG. 5, a female screw is formed at a position facing the screw mounting portion 101a of the mounting member 103, and the screw 102 is screwed into the female screw. The mounting member 103 is fixed to the plate 16 (FIG. 2) arranged on both sides of the printer 1. Base plate 1
Numeral 01 is bent upward on the back side of the printer 1, and the bent portion is attached via a screw 108 (FIGS. 2 and 4).

As shown in FIG. 6, a control board 104a for generating a video signal for driving a laser generator of the laser scanner unit 40 based on image data from a personal computer, and a commercial AC power supply are connected to a low voltage (for example, 5V). , 24V), an engine board 104c that supplies a low-voltage to a paper feed motor or the like to control the paper feed motor or the like, and boosts the output voltage of the low-voltage board 104a to increase the high voltage required for the printing process. Are disposed along the base plate 101, respectively. Hereinafter, the substrates 104a to 104a
04d is indicated without any particular distinction, "the substrate 10
4 ".

As shown in FIGS. 2, 5 and 6, the above-described screw 1 screwed to the mounting member 103 is attached to the substrate 104.
02 is penetrated, whereby the substrate 104 is attached to the mounting member 1.
03 and the base plate 101 to be fixed. A screw 10 is provided on the surface (lower surface) of the substrate 104.
2 is provided so as to surround the substrate 2, and when the substrate 104 is fixed with the screw 102,
The ground pattern is electrically connected to base plate 101. Also, the connection point 105 of the base plate 101
(FIG. 6) is an inlet (connector to which a commercial power supply line is connected) 106 via a lead wire (FIGS. 2 and 4).
(See Reference).

Thus, the substrate 104 is arranged along the base plate 101 maintained at the ground potential, and the ground lines are provided at a plurality of locations on the base plate 1.
01, the base plate 101 can be effectively used as an electromagnetic shield plate or as a low impedance ground line. Therefore, it is possible to realize a printer that is resistant to various noises.

The frame 16 is provided with screws 102-1 through 102-1.
By being connected to the base plate 101 via 102-3 (FIG. 6), it is electrically connected to the ground and exhibits a shielding effect.

In this embodiment, when the paper feed cassette 10 is pulled out, the screws 10 are
By removing 2 and the like, the base plate 101 and the substrate 104 can be removed via the space (see FIG. 3) secured above the cassette accommodating portion 100, that is, the cassette guide 15. As described above, in this embodiment, the base plate 101 can be easily removed, and the substrate 104 can be completely exposed to the bottom surface side of the printer 1. There is no need to remove the housed process cartridge 20, laser scanner unit 40, fixing unit 50, and the like.

In this embodiment, a sufficient length is secured for the lead wire for connecting the base plate 101 to the ground, and the base plate 101 can be removed with the lead wire connected. For this reason, there is no fear that the lead wires will be forgotten to be connected when the substrate 104 is replaced or the connection will be incomplete.

The screw 102 is connected to the base plate 101
Not only does it function as a fixing means for the substrate 104, but by removing the screw 102, the base plate 1
The fixing of the substrate 104 as well as 01 is released at the same time.
Therefore, the substrate 104 can be easily removed. Further, for example, in the replacement operation of the substrate 104,
Since the mounting of a new substrate 104 is completed only by fixing the base plate 101 with the screws 102, the substrate 104
It is possible to prevent a work error such as mounting the base plate 101 without noticing that the mounting is incomplete.

As shown in FIGS. 1, 2 and 5, the control board 104a is housed in a shield case SC attached to the base plate 101. The shield case SC is formed in a container shape having a rectangular opening. The opening end of the opening is bent inward, and the bent portion 94 is attached to the upper surface of the base plate 101 via a screw 102. . The cover 92 is detachably attached to the shield case SC via a screw 95.
Is attached. Shield case S with lid 92
The opening formed on the upper surface of C is covered. As shown in FIG. 5, the substrate 104a is sandwiched and fixed between the bent portion 94 and the base plate 101.

Although the control board 104a handles a high clock frequency and emits relatively large amounts of noise, in the present embodiment, the shield 90 is formed by the base plate 101 and the shield case SC.
4 is stored, so that noise emission can be sufficiently suppressed.

A lid 92 is detachably attached to the shield case SC via a screw 95. When the lid 92 is removed, a user or the like can access the rear of the printer 1 through the opening. The control board 104a can be easily accessed. For this reason, the lid 9
2, an additional board (for example, a memory board) 9 is attached to the connector 96 mounted on the control board 104 a.
1 can be inserted and removed.

In the present embodiment, since the control board 104a can be accessed from above only by removing the lid 92 without removing the base plate 101, the work of attaching and detaching the board 91 can be performed very easily. it can.

[0051]

According to the first aspect of the present invention, since the substrate can be detached by removing the first lid, the substrate can be detached without removing the image forming means. . Also, just by removing the second lid,
Part of the substrate can be exposed.

According to the third aspect of the present invention, the first lid can be attached and detached via the cassette accommodating portion.
By removing the lid, the substrate can be attached and detached, so that the substrate can be attached and detached without removing the image forming means.

In the image forming apparatus according to the third or fourth aspect, in the case of the fifth aspect, the substrate can be removed only by removing the first lid.

In the image forming apparatus according to the fifth or sixth aspect, in the case of the seventh aspect, the substrate can be fixed together with the first lid by fastening a screw.

In the image forming apparatus according to any one of the third to seventh aspects, in the case where the image forming apparatus is configured as in the eighth aspect, when the first lid is attached or detached, the connection of the lead wire is not established. There is no risk of perfection.

In the image forming apparatus according to any one of the third to ninth aspects, when the image forming apparatus is configured as in the tenth aspect, the second lid can be removed without removing the first lid. Thereby, a part of the substrate can be exposed.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment in which an image forming apparatus of the present invention is applied to a laser beam printer.

FIG. 2 is a view as seen from a direction of a line II-II in FIG. 1;

FIG. 3 is a view seen from the direction of line III-III in FIG. 1;

FIG. 4 is a perspective view showing the printer of FIG. 1;

FIG. 5 is a cross-sectional view of the printer of FIG. 1 taken along line VV of FIG. 6;

FIG. 6 is a bottom view of the printer shown in FIG. 1 in a state where a paper feed cassette is removed.

[Explanation of symbols]

 Reference Signs List 10 paper feed cassette 15 cassette guide 16 frame (plate member) 20 process cartridge 40 laser scanner unit 50 fixing unit 92 lid (second lid) 100 cassette storage 101 base frame (first lid) 102 screw 103 mounting member 104 substrate 104a control substrate

Claims (10)

[Claims] An image forming unit that forms a predetermined image; a storage unit that stores the image forming unit; and a substrate that is disposed below the image forming unit and stored in the storage unit. A first opening formed in a bottom surface of the storage, a first lid configured to open and close the first opening,
A second opening for exposing a part of the substrate;
And a second lid for opening and closing the opening of the image forming apparatus. The image forming apparatus is characterized in that the substrate can be attached and detached via the first opening. 2. A connector for allowing components to be attached to and detached from the board is disposed on an exposed portion of the board exposed through the second opening, and the second lid is opened. The printer according to claim 1, wherein the component is detachable through the second opening. 3. An image forming unit for forming a predetermined image, an image forming unit storing unit for storing the image forming unit, a substrate disposed below the image forming unit and stored in the storing unit, A cassette accommodating section provided below the image forming means accommodating section and removably accommodating a paper feed cassette, wherein the image forming means accommodating section is formed on a bottom surface of the image forming means accommodating section. A first opening and a first lid for opening and closing the first opening are provided; the substrate is detachable via the first opening; the first lid; The image forming apparatus is characterized in that the image forming apparatus is detachable via the cassette accommodating portion in a state where the sheet cassette is detached. And a guide for slidably supporting the paper feed cassette provided in the cassette housing portion, and a vertical direction secured between an upper end of the guide and a bottom surface of the image forming means housing portion. The said 1st lid part can be attached or detached via a clearance gap, The said 3rd part is characterized by the above-mentioned.
An image forming apparatus according to claim 1. 5. The first image forming apparatus according to claim 1, wherein
The substrate mounting member is provided so as to face the lid portion, and the substrate is fixed by being sandwiched between the substrate mounting member and the first lid portion. The image forming apparatus as described in the above. 6. A side surface of the image forming means housing portion and a side surface of the cassette housing portion extending in a direction along a direction in which the sheet cassette is attached and detached, respectively, are formed using a common plate-shaped member. The image forming apparatus according to claim 5, wherein the substrate mounting member is supported via the plate-shaped member. 7. The substrate according to claim 1, wherein the first cover is fixed via a screw screwed to the substrate mounting member, and the screw is penetrated through the substrate to fix the substrate. 7. The image forming apparatus according to 5 or 6. 8. A lead wire for connecting the first lid portion to the ground is connected between the first lid portion and a ground point in the image forming means accommodating portion, and the lead wire is connected. The image forming apparatus according to any one of claims 3 to 7, wherein the length of the lead wire is set so that the first lid portion can be removed in a state where the first lid portion is detached. 9. The image forming apparatus according to claim 1, wherein said board is a control board for controlling each part of the apparatus. 10. The image forming means accommodating section is further provided with a second opening for exposing a part of the substrate and a second lid for opening and closing the second opening. The image forming apparatus according to claim 3, wherein: