Image formation device

Abstract

To provide a technology capable of suppressing noise current superimposed on a current flowing through a cable by making an overlapping portion of the cable as short as possible.SOLUTION: A printer 1 includes: left and right main body frames 10 and 20; a scanner frame 30 suspended between the left and right main body frames 10 and 20; a scanner cover plate 40 covering the entire scanner frame 30 on which an exposure device is set; a main board 11 set on the left main body frame 10; a high-voltage power supply board 21 set on the right main body frame 20; and flexible first and second flat cables 61 and 62 passing over the scanner cover plate 40 and connecting the main board 11 and the high-voltage power supply board 21. The first and second flat cables 61 and 62 are connected to the main board 11 in an overlapping manner with each other and are connected to the high-voltage power supply board 21 side by side with each other, and the length of the overlapping portion is shorter than the length of the side-by-side portion.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] This application relates to a technique for arranging two flat cables that connect each board installed on both sides of a housing. [Background technology]

[0002] Patent Document 1 describes a connection means formed by overlapping parts of flat flexible cables. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-348740 Summary of the Invention [Problem to be solved by the invention]

[0004] It is known that the longer the overlapping portion of a cable, the more likely it is that noise current will be carried by the current flowing within the cable. However, the connection method described in Patent Document 1 does not mention the length of the overlapping portion of the cable, and therefore does not take into consideration the suppression of noise current by shortening the overlapping portion of the cable.

[0005] The present application aims to provide a technology that makes it possible to suppress noise currents carried on currents flowing inside cables by making the overlapping portions of the cables as short as possible. [Means for solving the problem]

[0006] In order to achieve the above object, the image forming apparatus of the present application comprises a pair of main body frames forming opposing side walls of a main body housing, a scanner frame suspended between one of the pair of main body frames and the other of the pair of main body frames, the scanner frame having an exposure device for exposing a photosensitive drum installed therein, a scanner cover plate covering the entire scanner frame on which the exposure device is installed, a first board installed on one of the main body frames, a second board installed on the other main body frame, a flexible first flat cable passing over the scanner cover plate to connect the first board and the second board, and a flexible second flat cable passing over the scanner cover plate to connect the first board and the second board, the first flat cable and the second flat cable overlapping each other and connected to the first board, and being aligned with each other and connected to the second board, the length of the overlapping portion being shorter than the length of the aligned portions.

[0007] In this way, in the image forming apparatus of the present application, the first flat cable and the second flat cable are arranged side by side over most of the relatively large area of ​​the scanner cover plate, making it possible to suppress noise currents carried on the currents flowing in the first flat cable and the currents flowing in the second flat cable. Also, because the first flat cable and the second flat cable are connected to the first board while overlapping each other, the two first and second flat cables can be arranged together in a compact manner.

[0008] Furthermore, by bending at least one of the first and second flat cables at least twice, the first and second flat cables change from overlapping to side-by-side. In this way, with the simple configuration of bending at least one of the first and second flat cables at least twice, the first and second flat cables can be changed from overlapping to side-by-side.

[0009] The image forming apparatus of the present application further includes a holder for holding the first and second flat cables, the scanner cover plate having a plurality of engagement holes, the holder having a plurality of engagement claws that engage with the plurality of engagement holes, and the holder being fixed to the scanner cover plate by engaging each of the engagement claws with each of the engagement holes in the scanner cover plate. By engaging each of the engagement claws of the holder with each of the engagement holes in the scanner cover plate in this manner, the holder can be fixed to the scanner cover plate, and heat generated by the exposure device within the scanner frame covered by the scanner cover plate can be released to the outside through each of the engagement holes in the scanner cover plate.

[0010] The image forming apparatus of the present application further includes at least two ferrite cores covering a portion of each of the first and second flat cables, each of the ferrite cores being located near the overlapping portion in the aligned portion. Since each of the first and second ferrite cores is located near the overlapping portion in the aligned portion, that is, the first and second ferrite cores are located near the overlapping portion of the first and second flat cables, where noise currents tend to flow, it is possible to better suppress noise currents carried on the currents flowing through the first and second flat cables.

[0011] The image forming apparatus of the present application is also characterized by further comprising a distance maintaining member for forming a predetermined gap between the first flat cable and the second flat cable at the overlapping portion of the first flat cable and the second flat cable. In this way, a predetermined gap is formed between the first flat cable and the second flat cable via the distance maintaining member at the overlapping portion of the first flat cable and the second flat cable, thereby making it possible to better suppress noise currents carried on the currents flowing through the first and second flat cables. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a perspective view showing an internal configuration of a color laser printer according to an embodiment of the present application. [Figure 2] 2 is a perspective view showing a state in which a scanner cover plate is attached to the scanner frame shown in FIG. 1. FIG. [Figure 3] 3 is a perspective view of the state of FIG. 2, seen from a different direction from FIG. 2. [Figure 4] FIG. 10 is a perspective view of a holder that holds two flat cables. [Figure 5] 5 is a perspective view showing a state in which the holder in FIG. 4 holds a flat cable and is installed on a scanner cover plate. FIG. [Figure 6] FIG. 5 is a perspective view of the same state as in FIG. 4, seen from a different direction than in FIG. 4. [Figure 7] FIG. 2 is an enlarged perspective view of an area A including a part of a main board to which a flat cable is connected. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present application will be described in detail with reference to the drawings. In the drawings used in the following description, some basic components may be omitted, and the dimensional ratios of the depicted components may not be accurate. In Figures 1 to 7, the front-rear direction D1, the up-down direction D2, and the left-right direction D3 are as shown in each figure.

[0014] FIG. 1 shows the internal configuration of a color laser printer 1 according to an embodiment of the present application. The color laser printer 1 is an example of the "image forming apparatus" of the present application. Hereinafter, the color laser printer 1 will be referred to as the printer 1 for short. As shown in FIG. 1, a pair of main body frames 10, 20 are erected inside the printer 1, forming opposing side walls of the main body housing. Of the pair of main body frames 10, 20, the main body frame forming the left side wall is referred to as the left main body frame 10, and the main body frame forming the right side wall is referred to as the right main body frame 20. The left main body frame 10 is an example of "one main body frame" of the present application, and the right main body frame 20 is an example of "the other main body frame" of the present application. Both the left main body frame 10 and the right main body frame 20 are formed, for example, from resin.

[0015] A scanner frame 30 is suspended between the left-side main frame 10 and the right-side main frame 20. The scanner frame 30 is for mounting an exposure device (not shown) that exposes four photosensitive drums (not shown) corresponding to four colors, for example, yellow, magenta, cyan, and black. The scanner frame 30 has a rectangular bottom surface 31 and side surfaces 32 that surround the bottom surface 31, and is box-shaped with an open top surface 33. The side surfaces 32 are made up of a front side surface 32A, a rear side surface 32B, a left side surface 32C, and a right side surface 32D.

[0016] The scanner frame 30 is fixed to the left body frame 10 and the right body frame 20 by screwing the left side surface 32C to the left body frame 10 and the right side surface 32D to the right body frame 20.

[0017] Four slits 31A to 31D are formed in the bottom surface 31 of the scanner frame 30. The exposure device installed in the scanner frame 30 emits a light beam through the slits 31A to 31D to each of the four photosensitive drums installed below the bottom surface 31, thereby exposing the surfaces of the photosensitive drums.

[0018] FIG. 2 shows the scanner cover plate 40 attached to the scanner frame 30 shown in FIG. 1. The scanner cover plate 40 covers the entire scanner frame 30 on which the exposure device is installed. The scanner cover plate 40 is composed of a top surface 41 having a truncated pyramidal protrusion 41C, a front side surface 42A extending downward from the front end of the top surface 41, and a rear side surface 42B extending downward from the rear end of the top surface 41. The left side surface, right side surface, and bottom of the scanner cover plate 40 are all open. The scanner cover plate 40 is fixed to the scanner frame 30 by screwing the front side surface 42A to the front side surface 32A of the scanner frame 30 and screwing the rear side surface 42B to the rear side surface 32B of the scanner frame 30. Furthermore, the scanner cover plate 40 is fixed to the left body frame 10 and the right body frame 20 by screwing the left end 41A of the top surface 41 to the left body frame 10 and the right end 41B of the top surface 41 to the right body frame 20.

[0019] Figure 3 shows the internal configuration of the printer 1 in Figure 2 as seen from a different direction than in Figure 2, specifically from the left front. As shown in Figure 3, a main board 11 is installed on the left side surface of the left body frame 10. The main board 11 is equipped with an ASIC (not shown) that controls the entire printer 1. The main board 11 is an example of the "first board" of the present application.

[0020] Meanwhile, as shown in FIG. 2 , a high-voltage power supply board 21 is mounted on the right side of the right-side main frame 20. The high-voltage power supply board 21 supplies high voltages, such as a development voltage and a charging voltage, to a process unit (not shown) including a photosensitive drum and an exposure device for forming an image on paper. The high-voltage power supply board 21 also has electronic components mounted thereon for controlling a fixing device (not shown) that fixes a toner image transferred onto a sheet. The printer 1 of this embodiment is configured so that the fixing device is user-replaceable. In printers without replaceable fixing devices, the fixing board mounted with the electronic components for controlling the fixing device was mounted on the main board 11. However, due to the replaceable fixing device, the fixing board cannot be mounted on the main board 11. Therefore, the electronic components for controlling the fixing device are mounted on the high-voltage power supply board 21. Therefore, while printers without replaceable fixing devices require only one flat cable for high-voltage power supply control to connect the main board 11 and the high-voltage power supply board 21, the printer 1 of this embodiment requires two cables: one for high-voltage control and one for fixing control. Therefore, main board 11 is equipped with female connectors 11A and 11B for connecting male connectors 61A and 62A (see FIG. 7) attached to the ends of two flat cables, as shown in FIG. 3. High-voltage power supply board 21 is an example of the "second board" of the present application.

[0021] Fig. 4 shows the configuration of a holder 50 that holds two flat cables. The holder 50 is installed on the scanner cover plate 40, as will be described later with reference to Figs. 5 and 6. As shown in Fig. 4, the holder 50 has two grooves, a first groove 51 and a second groove 52, for changing the two flat cables from a side-by-side state to an overlapping state, or conversely, for holding the two flat cables while changing the two flat cables from an overlapping state to a side-by-side state. The flat cable held in the first groove 51 is referred to as a first flat cable 61 (see Fig. 5), and the flat cable held in the second groove 52 is referred to as a second flat cable 62 (see Fig. 5).

[0022] The first groove 51 is formed with a plurality of first holding claws 51A for holding the first flat cable 61 in the first groove 51. The first groove 51 is also formed with two second holding claws 51B for holding a first ferrite core 71 (see FIG. 5) for covering a portion of the first flat cable 61 while the first flat cable 61 is held therein.

[0023] Similarly, the second groove portion 52 is also formed with a plurality of first retaining claws 52A for holding the second flat cable 62 within the second groove portion 52, and two second retaining claws 52B for holding a second ferrite core 72 (see Figure 5) for covering a portion of the second flat cable 62 while the second flat cable 62 is held.

[0024] The first groove 51 is formed linearly from the right end, i.e., the end close to the high-voltage power supply board 21, to the left end, i.e., the end close to the main board 11, although it has some undulations that follow the surface shape of the scanner cover plate 40. In contrast, the second groove 52 is formed linearly from the right end to the position where the second holding claw 52B is formed, but then moves closer to the first groove 51 as it approaches the left end, and at the left end, they are overlapped one above the other. The reason why the first groove 51 and the second groove 52 are formed in this manner is that at the right end, the first flat cable 61 and the second flat cable 62 are aligned with each other and connected to the respective connectors (not shown) of the high-voltage power supply board 21, while at the left end, the first flat cable 61 and the second flat cable 62 are overlapped with each other and connected to the female connectors 11A and 11B mounted vertically aligned on the main board 11. However, the length of the portion where the first flat cable 61 and the second flat cable 62 are aligned is made longer than the length of the portion where the first flat cable 61 and the second flat cable 62 overlap each other. This is because shortening the overlapping portion suppresses noise currents.

[0025] Furthermore, two engagement claws 53B, 54B are formed on the rear side adjacent to the first groove portion 51, and two engagement claws 53A, 54A are formed on the front side adjacent to the second groove portion 52. The engagement claws 53A, 54A are engaged with engagement holes 43A, 44A formed in the upper surface 41 and the protrusion 41C of the scanner cover plate 40, respectively, and the engagement claws 53B, 54B are engaged with engagement holes 43B, 44B formed in the upper surface 41 and the protrusion 41C of the scanner cover plate 40, respectively. This fixes the holder 50 onto the scanner cover plate 40.

[0026] 5 and 6 show a state in which the holder 50 is fixed onto the scanner cover plate 40 and the first flat cable 61 and the second flat cable 62 are held by the holder 50. Fig. 5 shows the interior of the printer 1 in this state as viewed from the front right, and Fig. 6 shows the interior of the printer 1 in this state as viewed from the front left. The reason why the holder 50 is fixed onto the scanner cover plate 40 in this manner is to suppress noise currents carried on the currents flowing in the first flat cable 61 and the second flat cable 62 by arranging the first flat cable 61 and the second flat cable 62 side by side over most of the relatively large area of ​​the scanner cover plate 40.

[0027] The second flat cable 62 extends linearly along the second groove 52 from the right end of the second groove 52 to the position where the second ferrite core 72 is held, then bent once to change direction in the front-to-rear direction, then bent once again to return to the left-to-right direction, then bent once more to change direction in the front-to-rear direction, then bent once more to return to the left-to-right direction, and then overlaps with the first flat cable 61. A plate-shaped sponge 75 is inserted in the overlapping portion between the first flat cable 61 and the second flat cable 62 to form a predetermined gap. The sponge 75 is an example of a "distance ensuring member" of the present application.

[0028] 5 and 6, the first ferrite core 71 and the second ferrite core 72 are arranged in positions close to the overlapping portion of the lined-up first flat cable 61 and second flat cable 62. This is because arranging the ferrite cores 71, 72 in positions close to the overlapping portion of the first flat cable 61 and the second flat cable 62, where noise current is likely to flow, increases the noise current suppression effect.

[0029] FIG. 7 shows a state in which a sponge 75 is inserted into the overlapping portion of the first flat cable 61 and the second flat cable 62. Area A is illustrated enlarged in FIG. 7. As shown in FIG. 7, the sponge 75 is inserted into the holder 50 from the overlapping portion of the first flat cable 61 and the second flat cable 62, and is positioned close to the connector 61A attached to the tip of the first flat cable 61. The sponge 75 is attached, for example, to the back side of the first flat cable 61 with double-sided tape. The sponge 75 is inserted into the overlapping portion of the first flat cable 61 and the second flat cable 62 in this manner in order to maximize the distance between the first flat cable 61 and the second flat cable 62 and thereby better suppress noise currents carried on the currents flowing through the first and second flat cables.

[0030] As described above, the printer 1 of this embodiment comprises two main body frames 10, 20 forming opposing side walls of the main body housing, a scanner frame 30 suspended between one left-hand main body frame 10 and the other left-hand main body frame 10 of the two main body frames 10, 20, the scanner frame 30 having an exposure device for exposing a photosensitive drum installed therein, a scanner cover plate 40 covering the entire scanner frame 30 on which the exposure device is installed, a main board 11 installed on the left-hand main body frame 10, a high-voltage power supply board 21 installed on the right-hand main body frame 20, a first flexible flat cable 61 passing over the scanner cover plate 40 to connect the main board 11 and the high-voltage power supply board 21, and a second flexible flat cable 62 passing over the scanner cover plate 40 to connect the main board 11 and the high-voltage power supply board 21, the first flat cable 61 and the second flat cable 62 overlapping each other and connected to the main board 11, and being side-by-side connected to the high-voltage power supply board 21, the length of the overlapping portion being shorter than the length of the side-by-side portions.

[0031] In this way, in the printer 1 of this embodiment, the first flat cable 61 and the second flat cable 62 are arranged side by side over most of the scanner cover plate 40, which has a relatively large area, making it possible to suppress noise currents carried on the currents flowing in the first flat cable 61 and the second flat cable 62. Furthermore, the first flat cable 61 and the second flat cable 62 are connected to the main board 11 overlapping each other, so the two first flat cable 61 and the second flat cable 62 can be arranged together in a compact manner.

[0032] Another feature is that by bending at least one of the first and second flat cables 61, 62 at least twice, the first and second flat cables 61, 62 change from overlapping to side-by-side. In this way, with the simple configuration of bending at least one of the first and second flat cables 61, 62 at least twice, the first and second flat cables 61, 62 can be changed from overlapping to side-by-side.

[0033] The scanner cover plate 40 further includes a holder 50 for holding the first and second flat cables 61, 62, the scanner cover plate 40 having a plurality of engagement holes 43A, 43B, 44A, 44B, the holder 50 having a plurality of engagement claws 53A, 53B, 54A, 54B that engage with the plurality of engagement holes 43A, 43B, 44A, 44B, respectively, and the holder 50 is fixed to the scanner cover plate 40 by engaging the respective engagement claws 53A, 53B, 54A, 54B with the respective engagement holes 43A, 43B, 44A, 44B of the scanner cover plate 40. This allows the holder 50 to be fixed to the scanner cover plate 40 by engaging the respective engagement claws 53A, 53B, 54A, and 54B of the holder 50 with the respective engagement holes 43A, 43B, 44A, and 44B of the scanner cover plate 40, and also allows heat generated by the exposure device within the scanner frame 30 covered by the scanner cover plate 40 to escape to the outside through the respective engagement holes 43A, 43B, 44A, and 44B of the scanner cover plate 40.

[0034] The cable further includes at least two first and second ferrite cores 71 and 72 that cover a portion of each of the first and second flat cables 61 and 62, and the first and second ferrite cores 71 and 72 are disposed near the overlapping portion of the adjacent cables. In this manner, the first and second ferrite cores 71 and 72 are disposed near the overlapping portion of the adjacent cables, i.e., the first and second ferrite cores 71 and 72 are disposed near the overlapping portion of the adjacent cables, where noise currents tend to flow. This makes it possible to better suppress noise currents carried on the currents flowing through the first and second flat cables 61 and 62.

[0035] The cable further includes a sponge 75 for forming a predetermined gap between the first flat cable 61 and the second flat cable 62 at the overlapping portion of the first flat cable 61 and the second flat cable 62. In this way, a predetermined gap is formed between the first flat cable 61 and the second flat cable 62 via the sponge 75 at the overlapping portion of the first flat cable 61 and the second flat cable 62, thereby better suppressing noise currents carried on the currents flowing through the first and second flat cables 61, 62.

[0036] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0037] (1) In the above embodiment, a color laser printer 1 was given as an example of an image forming apparatus, but a monochrome laser printer may also be used. Furthermore, the image forming apparatus is not limited to a standalone printer, and may be a multifunction device with a fax function or the like, or a copier.

[0038] (2) In the above embodiment, the second flat cable 62 is bent four times to change from a portion aligned with the first flat cable 61 to a portion overlapping the first flat cable 61. However, the number of times of bending is not limited to four, and may be two, six or more, as long as it is an even number of times. Furthermore, in the above embodiment, only the second flat cable 62 is bent. However, only the first flat cable 61 may be bent, or both the first flat cable 61 and the second flat cable 62 may be bent. In this case, the number of times the first flat cable 61 is bent and the number of times the second flat cable 62 is bent may be the same or different.

[0039] (3) In the above embodiment, electronic components for controlling the fixing device are mounted on the high-voltage power supply board 21. However, this is not limited to this. A fixing board mounted with electronic components for controlling the fixing device may be installed independently of the high-voltage power supply board 21 on the right-side main frame 20, and the first flat cable 61 may be connected to the high-voltage power supply board 21, and the second flat cable 62 may be connected to the fixing board.

[0040] (4) In the above embodiment, one ferrite core 71, 72 is provided for each of the flat cables 61, 62. However, the number of ferrite cores is not limited to one and may be two or more. Different numbers of ferrite cores may be provided for each of the flat cables 61, 62.

[0041] (5) In the above embodiment, the sponge 75 is given as an example of the distance ensuring member, but the material is not limited to this and a rubber plate or a plate-shaped foam may also be used. However, since both the first flat cable 61 and the second flat cable 62 are flexible, it is preferable that the distance ensuring member also be flexible. [Explanation of symbols]

[0042] 1...Color laser printer (image forming apparatus), 10...Left body frame (one of the body frames), 11...Main board (first board), 20...Right body frame (the other body frame), 21...High voltage power supply board (second board), 30...Scanner frame, 40...Scanner cover plate, 43A, 43B, 44A, 44B...Engagement holes, 50...Holder, 53A, 53B, 54A, 54B...Engagement claws, 61...First flat cable, 62...Second flat cable, 71...First ferrite core, 72...Second ferrite core, 75...Sponge (distance maintaining member).

Claims

1. a pair of main body frames forming opposing side walls of a main body housing; a scanner frame suspended between one of the pair of body frames and the other of the body frames, the scanner frame having an exposure device for exposing the photosensitive drum; a scanner cover plate that covers the entire scanner frame on which the exposure device is installed; a first substrate disposed on the one of the main body frames; a second substrate disposed on the other main body frame; a first flexible flat cable that passes over the scanner cover plate and connects the first board and the second board; a second flexible flat cable that passes over the scanner cover plate and connects the first board and the second board; Equipped with the first flat cable and the second flat cable are connected to the first substrate while overlapping each other, and are connected to the second substrate while being aligned with each other, and the length of the overlapping portion is shorter than the length of the aligned portions; An image forming apparatus characterized by:

2. The first and second flat cables are changed from the overlapping portion to the side-by-side portion by bending at least one of the first and second flat cables at least twice.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

3. a holder for holding the first and second flat cables; Furthermore, the scanner cover plate has a plurality of engagement holes; the holder has a plurality of engaging claws that engage with the plurality of engaging holes, The holder is fixed to the scanner cover plate by engaging each of the engagement claws with each of the engagement holes in the scanner cover plate.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

4. at least two ferrite cores covering a portion of each of the first and second flat cables; Furthermore, Each of the ferrite cores is disposed in the aligned portion at a position close to the overlapping portion.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

5. a distance ensuring member for forming a predetermined gap between the first flat cable and the second flat cable at the overlapping portion of the first flat cable and the second flat cable; 2. The image forming apparatus according to claim 1, further comprising:

Images