JP5117674B2 - Flat cable protection device, image forming device - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, and a facsimile, and a flat cable protection device used for them.

  In general, a flexible flat cable called FFC is rich in flexibility and can be bent into an arbitrary shape, so that a wiring space can be reduced. Also, there is a flexible printed circuit board called FPC as a flat circuit form like FFC, and typical examples of its construction method are (1) etching (2) printing. Expensive.

  However, the FFC has a flat tape shape, which is a feature of the FFC, so it is more likely to break than a harness bundled with ordinary wires. Especially, the end of the FFC is caught by hooking a tool or sheet metal during assembly or maintenance. It breaks easily. As a countermeasure against this, disconnection can be prevented by adhering the flat cable so as to be in close contact with the housing using an adhesive tape. However, sticking the tape is difficult to work in some places and is inferior to assembly. Further, since the FFC cannot be easily attached and detached, the maintenance is not good.

  In an image forming apparatus or the like, the FFC is likely to be a source of noise because it transmits an image control signal at a high speed. As a countermeasure, the FFC is preferably disposed in the apparatus so that the entire FFC contacts a metal casing.

However, when the FFC is disposed on the bottom surface or side surface of the housing, it is necessary to use a plurality of harness clamps in order to prevent the FFC from floating from the housing due to its flexibility. Even in such a case, it is difficult to completely prevent lifting between the clamps.
For example, as a conventional technique for reducing noise, there is a technique disclosed in Patent Document 1 in which a metal thin film layer is provided in an insulating layer of a flexible substrate, but it is more expensive than FFC.

By fixing the fixing means between the FFC and the plate-shaped protective member, it is possible to prevent stress from being applied to the end face of the FFC even when the FFC or the plate-shaped protective member is moved for some reason. For example, as a conventional technique, there is an example disclosed in Patent Document 2 in which a flexible substrate is held and protected by fitting a plate-like elastic protection member into a cut and raised portion of a casing. Since the protective member is not fixed, the end portion of the flexible substrate may come into contact with the above-mentioned cut and be damaged.
JP-A-7-283579 JP 2002-33306 A

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a low-cost flat cable protection device and an image forming apparatus using the same without sacrificing assembly and maintenance.

A flat cable protection device according to claim 1 of the present invention is
A flat cable for electrically connecting the first control board and the second control board;
The width is widely than the flat cable, a plate-shaped protective member can be bent by elastic deformation,
A fixing member for removably fixing the flat cable to a housing for attaching the first control board;
With
The fixing member integrally fixes the protective member and the flat cable so that the flat cable is sandwiched between the outer surface of the housing and the protective member,
The protective member includes a notch through which the clamp portion of the fixing member passes.
The housing has a hole for stopping the clamp portion of the fixing member that has passed through the notch,
The fixing member is a pair of elastic members for performing positioning by pressing the flat cable at a fixed position with respect to the housing in a state where the clamp portion passes through the notch and the hole of the housing. With a deformable part,
And said protective member to an end portion of the flat cable is bent to conform to one corner of the housing does not protrude to the front side of a portion bent from said side provided with the cutout of said protective member Bonding and fixing the flat cable and the protective member,
The fixing member, in a state in which the clamp portion is passed through the hole in the notch and the housing, elastic for positioning and pressing the position relative to the front Symbol housing the flat cable constant ing provided with a deformable portion,
It is characterized by that.

Those according to the claim 2 is the flat cable protection device of claim 1, before Kiho protection member has a notch on the perforated line, and performs bending by the elastic deformation at the notches.

In the image forming apparatus according to claim 3, the casing is a casing of the image forming apparatus, and the flat cable protection device according to claim 1 or 2 is used to attach the flat cable to the casing. Features.

The present invention can be superior in assemblability and maintainability compared to a method of fixing a flat cable to a casing with a tape.

  The best mode for carrying out the present invention will be described below with reference to the embodiments shown in the drawings.

  FIG. 1 is a view showing a device on which various substrates and devices are mounted and using an FFC as seen from the back. In the figure, 1 is a high-voltage power source, 2 is a control board called BiCU, 3 is a control board called IOB, and 4 is a controller board.

  2 and 3 are perspective views seen from the direction of arrow A in FIG. Referring to FIG. 2, the state in which the FFC 5 is attached to the housing is shown as seen from obliquely below. The housing at this time is called a controller box 6 including a plurality of control boards 2 to 4 and the like, and is made of sheet metal. Hereinafter, the case of the controller box 6 will be described with reference numeral 6a.

In the illustrated example, the FFC 5 electrically connects the control board 2 called BiCU and the control board 3 called IOB in the controller box 6. Further, in the illustrated example, the FFC 5 and the protective member 7 are plate-shaped having a width wider than that of the FFC 5 (in FIG. 2 to FIG. 4, the vertical dimension when viewed in the perspective direction on the drawing sheet) These members are bonded to the housing 6 a of the controller box 6 with double-sided tape, and are fixed to the controller box 6 with harness clamps 8.

  By fixing the FFC 5 and the plate-shaped protective member 7 as an adhesive, it is possible to prevent stress from being applied to the end face of the FFC 5 even when the FFC 5 or the plate-shaped protective member 7 is moved for some reason. In the case of holding and protecting a flexible substrate by inserting a plate-like elastic protection member into a part of the housing that has been cut and raised as in the past, the flexible substrate and the protection member are not fixed. Therefore, the end portion of the flexible substrate may come into contact with the above-described cut-and-raise and be damaged, but such a situation can be prevented in the present invention.

  As shown in FIG. 3, a perforated cut 9 is provided at a portion indicated by an arrow B of the protective member 7 so that it can be bent and is easily attached to the housing 6 a of the controller box 6. That is, since the FFC 5 can be bent or elastically deformed, it has a characteristic that signals can be transmitted in a space-saving manner within the apparatus, so that the plate-like protection member 7 can also be bent or elastically deformed. For example, the characteristics of the FFC 5 are not impaired while preventing the FFC 5 from being damaged.

  FIG. 4 is a perspective view showing a state in which the harness clamp 8 is removed from the state of FIG. The protective member 7 is provided with notches 7a and 7b for mounting the harness clamp 8 as shown in the figure, and the clamp portions 8a and 8b of the harness clamp 8 are just fitted. The harness clamp 8 is so-called patched in square holes 6b and 6b provided in the housing 6a of the controller box 6. By adopting such a structure, the FFC 5 can be easily positioned, so that the assemblability is excellent. In addition, since the position of the FFC 5 can be made constant, variations in noise characteristics due to the apparatus can be stabilized.

  5 is a cross-sectional view of the harness clamp 8 taken along the line VV in FIG. The harness clamp 8 is provided with elastically deformable portions 8c and 8c (only one is shown in the figure) so that the elastically deformable portions 8c and 8c press the protective member 7 when the harness clamp 8 is attached to the housing 6a. It has become.

  Since the protective member 7 is made of, for example, a polycarbonate resin sheet having a thickness of 0.5 mm and having an appropriate rigidity, the entire FFC 5 (integrated with the protective sheet 7 is integrated with one harness clamp 8). 4: In the case of FIG. 4, the end portion provided with the notches 7 a and 7 b to the bent portion referred to in the example of FIG. In the illustrated embodiment, a commercially available product is used for the harness clamp, but of course the same applies to a special product designed for the apparatus.

That is, the flexible flat cable generally called FFC is easy to break compared with a harness bundled with a general electric wire because of the flat tape shape that is a feature of the flexible flat cable. Sometimes it breaks easily by hooking a tool or sheet metal, etc., and can be prevented by sticking it to the housing with an adhesive tape, but it is difficult to stick the tape or FFC The maintenance was not good because it could not be removed and attached easily, but the flat cable was fixed by the fixing member so that it was sandwiched between the outer surface of the housing and the protective member. The housing is provided with a cutout, and the housing is provided with a hole for stopping the clamp part of the fixing member that has passed through the cutout. The cable and the position relative to the housing in a fixed a structure that allows the positioning, such as tools and metal plate can be prevented by the protective member coming into contact with the edge of the flat cable, and a detachable fixing member from the housing As a result , as compared with the method of fixing the flat cable to the casing with tape, the assembly and maintenance are superior.

  Further, since the FFC transmits image control signals at high speed and is likely to be a source of noise, it has been preferable to arrange the FFC in the apparatus so that the entire FFC contacts the metal casing. Even if it does not do so in the present invention, since the flat cable harness clamp presses the plate-shaped protective member having a certain degree of rigidity, the flat cable can be brought into close contact with the housing with a small number of parts. Noise generated from electronic equipment can be reduced at low cost.

The figure which mounts various substrates and apparatuses, and shows the apparatus which uses FFC from the back The perspective view seen from the direction of arrow A in FIG. The perspective view seen from the direction of arrow A in FIG. The perspective view which shows the state which removed the harness clamp from the state of FIG. VV sectional view of the harness clamp in FIG.

Explanation of symbols

1: High-voltage power supply 2: Control board called BiCU 3: Control board called IOB 4: Controller board FFC5
Controller box 6
Controller box housing 6a
Protective member 7
Harness clamp 8
Notch 9
Notches 7a, 7b
Clamp part 8a, 8b
Square holes 6b, 6b
Elastically deformable parts 8c, 8c

Claims (3)

A flat cable for electrically connecting the first control board and the second control board;
The width is widely than the flat cable, a plate-shaped protective member can be bent by elastic deformation,
A fixing member for removably fixing the flat cable to a housing for attaching the first control board;
With
The fixing member integrally fixes the protective member and the flat cable so that the flat cable is sandwiched between the outer surface of the housing and the protective member,
The protective member includes a notch through which the clamp portion of the fixing member passes.
The housing has a hole for stopping the clamp portion of the fixing member that has passed through the notch,
The fixing member is a pair of elastic members for performing positioning by pressing the flat cable at a fixed position with respect to the housing in a state where the clamp portion passes through the notch and the hole of the housing. With a deformable part,
And said protective member to an end portion of the flat cable is bent to conform to one corner of the housing does not protrude to the front side of a portion bent from said side provided with the cutout of said protective member Bonding and fixing the flat cable and the protective member,
The fixing member, in a state in which the clamp portion is passed through the hole in the notch and the housing, elastic for positioning and pressing the position relative to the front Symbol housing the flat cable constant ing provided with a deformable portion,
A flat cable protection device. The flat cable protection device of claim 1,
Before Kiho protection member has a notch on the perforated line, the flat cable protection device and performs bending by the elastic deformation at the notches. An image forming apparatus, wherein the housing is a housing of an image forming apparatus, and the flat cable protection device according to claim 1 or 2 is used to attach a flat cable to the housing .