Image forming device

Abstract

To fix an electric wave absorber such as a ferrite core to a wire part without using a fixation member.SOLUTION: An image formation device includes an AC control unit, a fixation unit, and a harness unit 401 for connecting the AC control unit and the fixation unit to each other. The harness unit 401 includes: a plurality of harness guides 422 and 423 fixed to the frame of the image formation device; a harness 411 guided by the harness guides 422 and 423; and a ferrite core 421 having a through-hole 426 in which the harness 411 is inserted. The ferrite core 421 is held between the harness guide 422 and the harness guide 423.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus such as a copying machine, a printer, or a multifunction machine. [Background technology]

[0002] Image forming apparatuses have a tendency to produce more electrical noise as they become more colorized and faster. In order to reduce electrical noise, it is common to attach radio wave absorbers such as ferrite cores to the wiring parts of wiring members used for transmitting signals and supplying power within the device. For example, harnesses are used for the wiring parts of the wiring members, in which multiple electric wires are bundled together and a multi-core connector is attached to the end of the harness. By using the harness, for example, signal transmission and power supply can be performed with a single wiring member. Patent Document 1 discloses a fixing member for attaching a ferrite core to an optimal position of the wiring part to which the ferrite core is to be attached. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-109574 A Summary of the Invention [Problem to be solved by the invention]

[0004] Conventionally, a fixing member is used to hold the position of a ferrite core attached to a wiring portion of a harness, etc., and therefore, the cost of the fixing member is required. In view of such a problem, the present invention aims to provide a technology for fixing a radio wave absorber such as a ferrite core to a wiring portion without using a fixing member. [Means for solving the problem]

[0005] The image forming apparatus of the present invention is an image forming apparatus including a first component, a second component, and a wiring member connecting the first component and the second component, the wiring member being fixed to a frame of the image forming apparatus and including a plurality of guide members including at least a first guide member and a second guide member, a wiring portion guided by the plurality of guide members, and a radio wave absorber having a through hole through which the wiring portion is inserted; each of the first guide member and the second guide member has a long U-shape, the wiring portion is disposed on a bottom surface of the U-shape, the first guide member and the second guide member are arranged side by side in a longitudinal direction, The radio wave absorber is characterized in that it is sandwiched between the first guide member and the second guide member. Another image forming apparatus of the present invention is an image forming apparatus comprising a first part, a second part, and a wiring member connecting the first part and the second part, wherein the wiring members are each fixed to a frame of the image forming apparatus and include a plurality of guide members including at least a first guide member and a second guide member, a wiring portion guided by the plurality of guide members, and a ferrite core having a through hole through which the wiring portion is inserted, wherein each of the first guide member and the second guide member is a long U-shape, the wiring portion is disposed on a bottom surface of the U-shape, the first guide member and the second guide member are arranged side by side in the longitudinal direction, and the ferrite core is clamped between the first guide member and the second guide member. Effect of the Invention

[0006] According to the present invention, it is possible to fix the radio wave absorber to the wiring portion without using a fixing member. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is an overall configuration diagram of an image forming apparatus. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] 1A and 1B are explanatory diagrams showing the arrangement and size of each part of the harness unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] 1 is a diagram showing the overall configuration of an image forming apparatus according to this embodiment. The image forming apparatus 100 according to this embodiment is a tandem intermediate transfer type full-color printer in which image forming units 1a, 1b, 1c, and 1d are arranged along the downward surface of an intermediate transfer belt 2. The image forming apparatus 100 forms an image on a sheet S. The image forming apparatus 100 includes a document scanner 50 at its upper portion. A post-processing unit 70 having a paper discharge tray 7 is connected to the image forming apparatus 100 at its rear stage.

[0010] The document scanner 50 reads an image of an original document and transmits the read image as image data to the image forming apparatus 100. The image forming apparatus 100 forms an image on a sheet S based on the image data acquired from the document scanner 50 (copying process). Note that the image forming apparatus 100 can also form an image on a sheet S based on image data acquired from an external device other than the document scanner 50 (printing process).

[0011] The image forming apparatus 100 includes a recording material cassette 4 that stores sheets S, and a separation roller 8 that feeds the sheets S from the recording material cassette 4. The separation roller 8 separates the sheets S stored in the recording material cassette 4 one by one and feeds them to a transport path. A registration roller 9 and a secondary transfer roller 22 are provided on the transport path. The sheet S fed by the separation roller 8 is transported to the registration roller 9. The registration roller 9 receives the sheet S in a stopped state, corrects any skew of the sheet S, and waits. The registration roller 9 starts transporting the sheet S to the secondary transfer roller 22 in accordance with the timing at which a toner image is formed.

[0012] Image forming units 1a, 1b, 1c, and 1d have the same configuration, but the colors of the images (toner images) they form are different. Image forming units 1a, 1b, 1c, and 1d are equipped with photosensitive drums a, b, c, and d. Image forming unit 1a forms a yellow toner image on photosensitive drum a. Image forming unit 1b forms a magenta toner image on photosensitive drum b. Image forming unit 1c forms a cyan toner image on photosensitive drum c. Image forming unit 1d forms a black toner image on photosensitive drum d.

[0013] The photosensitive drums a, b, c, and d have a photosensitive layer with a negative polarity on the outer circumferential surface. The photosensitive layers of the photosensitive drums a, b, c, and d are charged to a uniform negative potential by a charging roller (not shown). The exposure device 6 provided below the image forming units 1a, 1b, 1c, and 1d scans a laser beam with a rotating mirror to form an electrostatic latent image on the charged surface of the photosensitive drums a, b, c, and d. The electrostatic latent image formed on the photosensitive drums a, b, c, and d is reverse-developed into a toner image by a developing device (not shown) built into the image forming units 1a, 1b, 1c, and 1d.

[0014] Primary transfer rollers 2a, 2b, 2c, and 2d are arranged opposite the photosensitive drums a, b, c, and d with the intermediate transfer belt 2 interposed therebetween, and form primary transfer portions Ta, Tb, Tc, and Td between the photosensitive drums a, b, c, and d. The photosensitive drums a, b, c, and d come into contact with the intermediate transfer belt 2 through the primary transfer portions Ta, Tb, Tc, and Td. A positive DC voltage is applied to the primary transfer rollers 2a, 2b, 2c, and 2d, so that the negative toner images carried on the photosensitive drums a, b, c, and d are primarily transferred to the intermediate transfer belt 2 passing through the primary transfer portions Ta, Tb, Tc, and Td.

[0015] The intermediate transfer belt 2 is wound around a secondary transfer tension roller 25 and a drive roller 26. The intermediate transfer belt 2 is rotated in the direction of arrow R2 by the drive roller 26. The primary transfer of the toner images from the photosensitive drums a, b, c, and d is performed at a timing such that the toner images are superimposed on the intermediate transfer belt 2 according to the rotation speed of the intermediate transfer belt 2. As a result, the intermediate transfer belt 2 carries a full-color toner image.

[0016] The secondary transfer tension roller 25 forms a secondary transfer portion T2 between itself and the secondary transfer roller 22. At the same time that the toner image carried by the intermediate transfer belt 2 reaches the secondary transfer portion T2, the sheet S reaches the secondary transfer portion T2. ​​The secondary transfer portion T2 brings the intermediate transfer belt 2 into contact with the sheet S. A positive DC voltage is applied to the secondary transfer roller 22, thereby forming a transfer electric field for the toner image between itself and the secondary transfer tension roller 25, which is connected to a ground potential. The toner image carried by the intermediate transfer belt 2 is secondarily transferred to the sheet S by the transfer electric field.

[0017] A fixing unit 5 is provided downstream of the secondary transfer portion T2 in the conveying direction of the sheet S. The fixing unit 5 includes a fixing roller 5a incorporating a fixing heater, and a pressure roller 5b. A heating nip is formed by pressing the pressure roller 5b against the fixing roller 5a. As the sheet S with the transferred toner image is sandwiched and conveyed in the heating nip, the toner image is melted and pressed by the heat of the fixing heater. This fixes the image on the surface of the sheet S.

[0018] The sheet S on which the image has been fixed by the fixing unit 5 is discharged from the discharge roller 11 to the discharge path unit 60. The sheet S discharged to the discharge path unit 60 is transported to the post-processing unit 70. The post-processing unit 70 performs necessary post-processing on the sheet S and then discharges the sheet S to the discharge tray 7.

[0019] 2 is an explanatory diagram of a control unit that controls the overall operation of the image forming apparatus 100. The control unit 200 is built into the image forming apparatus 100. The control unit 200 drives loads arranged in the image forming apparatus 100, collects and analyzes information using sensors, and controls image formation. The control unit 200 controls communication with the document scanner 50 and the post-processing unit 70, and controls an operation unit 202 that is a user interface.

[0020] The operation unit 202 includes an input interface and an output interface. The input interface is, for example, various buttons, a touch panel, etc. The output interface is, for example, a display, a speaker, etc. Instructions, settings, etc. input from the input interface of the operation unit 202 are transmitted to the control unit 200. The control unit 200 operates based on the instructions, settings, etc. acquired from the operation unit 202. The control unit 200 displays various setting screens and the status of the image forming apparatus 100 on the display of the operation unit 202.

[0021] The control unit 200 is an information processing device having a CPU (Central Processing Unit) 2011, a RAM (Random Access Memory) 2012, and a ROM (Read Only Memory) 2013. The CPU 2011 executes computer programs stored in the ROM 2013 to execute processes by the image forming apparatus 100, such as image formation control. The RAM 2012 provides a working area for the CPU 2011 when executing processes. The RAM 2012 can retain data by a battery (not shown) or the like even when the image forming apparatus 100 is powered off.

[0022] The CPU 2011 is connected to a high voltage control unit 205, a motor control unit 207, a DC load control unit 208, a fan control unit 215, a sensor I / F 209, an AD converter 252, and an AC control unit 264. A high voltage unit is connected to the high voltage control unit 205. Various motors 212 are connected to the motor control unit 207. A clutch / solenoid (CL, SL) 213 is connected to the DC load control unit 208. Various fans 216 are connected to the fan control unit 215. Sensors 214 are connected to the sensor I / F 209. A thermistor 253 built in the fixing unit 5 is connected to the AD converter 252. A fixing heater 265 built in the fixing unit 5 is connected to the AC control unit 264.

[0023] The sensor I / F 209 is an interface for acquiring the detection results from the sensors 214. The CPU 2011 acquires detection signals representing the detection results from the sensors 214 arranged in each part within the image forming apparatus 100 via the sensor I / F 209. The CPU 2011 transmits various control signals to the high voltage control unit 205, the motor control unit 207, the DC load control unit 208, and the fan control unit 215 based on the acquired detection signals. The control signals control the operation of each part.

[0024] The high voltage control unit 205 outputs a predetermined high voltage from the high voltage unit 206 in response to the control signal. The high voltage unit 206 outputs high voltages such as a voltage for charging the photosensitive drums a, b, c, and d, a DC voltage during primary transfer, a DC voltage during secondary transfer, and a voltage during development. The motor control unit 207 controls the drive of various motors 212 arranged in various parts of the image forming apparatus 100 in response to the control signal. The various motors 212 are drive sources for each roller for conveying the sheet S, drive sources for rotating the photosensitive drums a, b, c, and d, and drive sources for rotating the drive roller 26. The DC load control unit 208 controls the drive of clutches / solenoids 213 arranged in various parts of the image forming apparatus 100 in response to the control signal. The clutches / solenoids 213 are used to drive and stop the registration rollers 9, for example.

[0025] The CPU 2011 obtains a digital signal representing the detection result by the thermistor 253 from the AD converter 252. The thermistor 253 is a temperature sensor for detecting the temperature of the fixing unit 5 (fixing heater 265). The CPU 2011 detects the temperature of the fixing unit 5 using the digital signal, and transmits a control signal according to the detected temperature to the AC control unit 264. The AC control unit 264 performs ON / OFF control of the fixing heater 265 based on the control signal obtained from the CPU 2011. In this way, the temperature of the fixing heater 265 is controlled. The AC control unit 264 supplies power to the post-processing unit 70 according to an instruction from the CPU 2011.

[0026] 3 is a rear view of the image forming apparatus 100. The control unit 200 is disposed above the image forming apparatus 100. The AC control unit 264 is disposed on the bottom surface of the image forming apparatus 100. The fixing unit 5 and the post-processing unit connection unit 405 are components to which AC power is supplied from the AC control unit 264. The post-processing unit connection unit 405 supplies AC power to the post-processing unit 70. In addition, the post-processing unit connection unit 405 transmits a control signal obtained from the control unit 200 to the post-processing unit 70. The operation of the post-processing unit 70 is controlled by the control signal.

[0027] AC control unit 264 is supplied with AC power from a commercial power source via power cord 400. AC control unit 264 supplies AC power to fixing unit 5 via harness unit 401, which is a wiring member. AC control unit 264 also supplies AC power to post-processing unit connection unit 405 via harness unit 402, which is a wiring member.

[0028] 4 is a perspective view of harness unit 401. Harness unit 401 includes harness 411, which is a wiring portion formed by bundling a plurality of electric wires, a ferrite core 421, and a plurality of harness guides 422 and 423. Harness unit 401 is fixed to image forming apparatus 100 by fixing harness guides 422 and 423 to a metal frame inside the housing of image forming apparatus 100 by fixing portion 424 with screws or the like.

[0029] The harness guides 422 and 423 are guide members that guide the harness 411 and fix the harness 411 to the wiring path. The harness guides 422 and 423 are long U-shaped. The harness guides 422 and 423 are arranged side by side in the longitudinal direction. The harness 411 is disposed on the bottom surface of the U-shape of the harness guides 422 and 423. A protrusion 425 is provided on the open part of the U-shape so that the harness 411 does not come out of the U-shaped groove. The harness 411 is disposed in the U-shaped groove of the harness guides 422 and 423 so as not to come into direct contact with the metal frame of the image forming apparatus 100.

[0030] Since the harness 411 of this embodiment is a wiring portion that supplies AC power, it is required to have insulation from metal. For this reason, the harness guides 422 and 423 are formed of insulating resin or the like. The harness guides 422 and 423 are configured to maintain the insulation of the harness 411 even if the covering of the harness 411 is scratched or has a pinhole. It is desirable that the harness guides 422 and 423 are integrally formed over the entire length of the harness 411. However, the longer the harness guides 422 and 423 are, the more difficult and expensive it becomes to create a mold for manufacturing them. For this reason, the harness guides 422 and 423 are configured by dividing them into a plurality of parts. In this embodiment, two harness guides, the harness guide 422 and the harness guide 423, are used for the harness 411. If the harness 411 is even longer, three or more harness guides may be used.

[0031] The ferrite core 421 is an example of a radio wave absorber provided to reduce electrical noise generated from the image forming apparatus 100. The ferrite core 421 is a cylindrical body having a through hole 426, and the harness 411 is inserted through the through hole 426. The ferrite core 421 is sandwiched between the harness guide 422 and the harness guide 423. The position of the ferrite core 421 is fixed by being sandwiched between the harness guide 422 and the harness guide 423. In this embodiment, the cylindrical ferrite core 421 will be described, but the ferrite core 421 may be a square tube as long as it has the through hole 426.

[0032] 5 is an explanatory diagram of the arrangement and size of each part of the harness unit 401. As shown in Fig. 5(a), the length of the through hole 426 of the ferrite core 421 is P, and the distance between the harness guide 422 and the harness guide 423 is Q. In this case, the relationship is P≦Q<2*P. In other words, the harness guide 422 and the harness guide 423 are arranged with a gap between them so that the distance Q is equal to or greater than the length P of the through hole 426 and less than twice the length P of the through hole 426.

[0033] As shown in FIG. 5(b), let the inner diameter of the ferrite core 421 be d and the outer diameter be D. Also, let the inner dimensions of the U-shaped width and height of the harness guide 422 in the S cross-sectional direction of FIG. 5(a) be w and t, and the outer dimensions be W and T. In this case, the relationships t < D, w < D, d < T, and d < W hold. The same applies to the harness guide 423. That is, the outer diameter D of the ferrite core 421 is larger than the inner dimension of the U-shape of the harness guide 422, and the inner diameter d of the ferrite core 421 is smaller than the outer dimension of the U-shape of the harness guide 422. By using the ferrite core 421 and the harness guides 422 and 423 of such sizes, the ferrite core 421 is sandwiched by the harness 411 and the harness guides 422 and 423. Therefore, the ferrite core 421 is fixed so as not to move by more than a predetermined amount.

[0034] As described above, a wiring member provided with the harness guides 422 and 423 for fixing and protecting the harness 411 is used for power supply and signal transmission between components in the electronic device. The ferrite core 421 that suppresses electrical noise generated from the harness 411 is fixed by the harness guide 422 and the harness guide 423. Therefore, a fixing member for fixing the ferrite core 421 becomes unnecessary, and it becomes possible to reduce costs.

[0035] In addition, in FIGS. 4 and 5, the harness unit 401 has been described. However, by adopting the same configuration for the harness unit 402, the same effects can be obtained. Also, in this embodiment, the harness units 401 and 402 as wiring members for supplying AC power have been described. However, the harness units 401 and 402 are also applicable when transmitting signals such as DC power and control signals.

Claims

1. A first part; A second part; a wiring member connecting the first component and the second component, The wiring member is a plurality of guide members each fixed to a frame of the image forming apparatus, the guide members including at least a first guide member and a second guide member; a wiring portion guided by the plurality of guide members; a radio wave absorber having a through hole through which the wiring portion is inserted, each of the first guide member and the second guide member has an elongated U-shape, and the wiring portion is disposed on a bottom surface of the U-shape; The first guide member and the second guide member are arranged side by side in a longitudinal direction, The radio wave absorber is sandwiched between the first guide member and the second guide member. Image forming device.

2. a distance between the first guide member and the second guide member is equal to or greater than a length of the through hole of the radio wave absorber and is less than twice the length of the through hole, 2. The image forming apparatus according to claim 1.

3. The inner diameter of the radio wave absorber is smaller than the outer dimension of the U-shape.

2. The image forming apparatus according to claim 1.

4. The outer diameter of the radio wave absorber is larger than the inner dimension of the U-shape.

4. The image forming apparatus according to claim 1.

5. The radio wave absorber is a cylindrical ferrite core. The image forming apparatus according to any one of claims 1 to 4.

6. A first part; A second part; a wiring member connecting the first component and the second component, The wiring member is a plurality of guide members each fixed to a frame of the image forming apparatus, the guide members including at least a first guide member and a second guide member; a wiring portion guided by the plurality of guide members; a ferrite core having a through hole through which the wiring portion is inserted, each of the first guide member and the second guide member has an elongated U-shape, and the wiring portion is disposed on a bottom surface of the U-shape; The first guide member and the second guide member are arranged side by side in a longitudinal direction, The ferrite core is sandwiched between the first guide member and the second guide member. Image forming device.

7. A distance between the first guide member and the second guide member is equal to or greater than a length of the through hole of the ferrite core and is less than twice the length of the through hole.

7. The image forming apparatus according to claim 6.

8. The inner diameter of the ferrite core is smaller than the outer dimension of the U-shape.

7. The image forming apparatus according to claim 6.

9. The outer diameter of the ferrite core is larger than the inner dimension of the U-shape.

9. The image forming apparatus according to claim 6 or 8.

10. The ferrite core is cylindrical. The image forming apparatus according to any one of claims 6 to 8.

11. The wiring portion is a harness formed by bundling a plurality of electric wires. The image forming apparatus according to any one of claims 1 to 10.

12. Electric power is supplied from the first component to the second component via the wiring member. The image forming apparatus according to any one of claims 1 to 11.

13. A signal is transmitted from the first component to the second component via the wiring member. The image forming apparatus according to any one of claims 1 to 12.

Images