Structure, housing, and image forming apparatus

Abstract

To prevent deterioration in electric characteristics due to increase in inductance.SOLUTION: A structure including a first plate-shaped part having electrical conductivity and a second plate-shaped part having electrical conductivity, the structure including a first conductive member and a second conductive member that are provided so as to extend from the first plate-shaped part and have open ends as end portions, the structure being characterized in that, in a state where the first plate-shaped part and the second plate-shaped part are joined to each other, the first conductive member is provided so as to be in contact with the second plate part, the second conductive member is provided so as not to be in contact with the second plate part, and a capacitance value between the second conductive member and the second plate part is 1. 4pF or more and 100pF or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a structure, a housing, and an image forming apparatus. [Background technology]

[0002] Electronic devices are equipped with electrical circuits that include multiple circuits capable of inputting or outputting signals. When each circuit operates, a current corresponding to the operation propagates through the printed circuit board on which the electrical circuit is mounted, generating high-frequency noise current and voltage, which then flow into conductive devices via contacts between the devices. Structures formed through such contacts form a resonant system in a specific frequency band, posing a problem of generating large amounts of unwanted radiation noise. Patent Document 1 therefore discloses a configuration in which the components that make up an electronic device are electrically connected via spring components. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-283191 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the configuration of Patent Document 1, since spring parts are interposed between the respective parts, there is a risk that the inductance of the elastic member will increase. Therefore, an object of the present invention is to prevent the deterioration of electrical characteristics due to the increase in inductance. [Means for solving the problem]

[0005] The means for solving the above problem is a structure comprising a first plate-shaped portion having electrical conductivity and a second plate-shaped portion having electrical conductivity, wherein the structure comprises a first conductive member and a second conductive member extending from the first plate-shaped portion and having open ends, wherein when the first plate-shaped portion and the second plate-shaped portion are joined together, the first conductive member is arranged so as to be in contact with the second plate-shaped portion and the second conductive member is arranged so as not to be in contact with the second plate-shaped portion, and the capacitance value between the second conductive member and the second plate-shaped portion is 1.4 pF or more and 100 pF or less. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a technique that is advantageous in preventing deterioration of electrical characteristics due to an increase in inductance of an elastic member. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view of a housing constituting the structure of the present invention. [Figure 2] FIG. 10 is a schematic diagram of a structure according to a comparative example. [Figure 3] 1 is a graph showing the results of an example and a comparative example. [Figure 4] FIG. 10 is a diagram showing a first modified example of the first embodiment. [Figure 5] FIG. 10 is a diagram showing a second modified example of the first embodiment. [Figure 6] 1 is a perspective view of an image forming apparatus to which the structure of an embodiment can be applied; [Figure 7] FIG. 2 is a schematic diagram of an image forming unit installed in the image forming apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, a description will be given of an embodiment of the present invention with reference to the drawings. However, the embodiment described below is one embodiment of the invention and is not limited to this. Common configurations will be described with mutual reference to multiple drawings, and descriptions of configurations with common reference numerals will be omitted as appropriate. Items with the same name but different features can be distinguished by adding "0", such as the first feature and the second feature.

[0009] FIG. 1 is a perspective view showing an embodiment in which the structure of the present invention is applied to a housing 1 made of a metal plate. The housing 1 is composed of a container 2 formed from a metal plate and a lid 3 (second plate-shaped portion) that covers the opening of the container 2. The container 2 has a mounting surface 4 (first plate-shaped portion) formed by bending the edge of the metal plate. The lid 3 is placed on the mounting surface 4 of the container 2 and secured with screws or welding, thereby forming the housing 1 into a box shape. The housing 1 can be used as a housing for home appliances or personal computers, or as a control box for a copier or processing machine, and electrical components or control-related devices can be attached or stored inside the container 2. To prevent static electricity and electromagnetic interference generated within the housing 1, the container 2 and the lid 3 are each made of a conductive material such as metal. Furthermore, the structure ensures electrical continuity between the container 2 and the lid 3 so that when either the container 2 or the lid 3 is grounded, the other is also grounded. The conductive materials forming the container 2 and the lid 3 may be the same material or different materials.

[0010] The metal plate material used for the container 2 and lid 3 of the housing 1 is preferably a conductive sheet metal material such as iron or copper, which has a low electrical resistance. The thickness of the plate material is preferably 0.4 to 1.2 mm. The present invention can be implemented with any material and thickness that is a conductive material that can be plastically deformed.

[0011] First Embodiment A structural body 6 according to this embodiment will be described with reference to Fig. 1. Fig. 1(a) is a perspective view showing an embodiment in which the structural body 6 according to this embodiment is applied to a housing 1 made of a metal plate. Fig. 1(b) is an enlarged front view of the structural body 6 according to this embodiment as viewed in the C3 direction, and Fig. 1(c) is an enlarged top view of the structural body 6 according to this embodiment as viewed from above (the second plate-shaped portion 102 is not shown).

[0012] Structure 6 is a contact structure between plate-shaped portion 101 (first plate-shaped portion) and plate-shaped portion 102 (second plate-shaped portion), where plate-shaped portion 101 is provided, for example, on mounting surface 4 of container 2, and plate-shaped portion 102 is provided, for example, on container 2. Then, lid 3 is placed on mounting surface 4, so that plate-shaped portion 101 and plate-shaped portion 102 overlap and join with each other. By overlapping lid 3 on container 2 and establishing conductivity in structure 6, it is possible to suppress leakage of high-frequency noise current or large unwanted radiation noise caused by forming a resonant system in a specific frequency band.

[0013] 1, elastic member 5a (first conductive member) and elastic member 5b (second conductive member) are provided on mounting surface 4 of container 2, but elastic member 5a and elastic member 5b may be provided on lid 3. In other words, plate-like portion 101 and second plate-like portion 102 of the structure each constitute either the container or the lid that covers the opening of the container.

[0014] In the structure 6 according to this embodiment, elastic members 5a and 5b are provided on a plate-shaped portion 101, each having an open end 50a, 50b. The elastic member 5a extends in a direction C1, and the elastic member 5b extends in a direction C2. In this embodiment, the elastic member 5a extending from the plate-shaped portion 101 is provided to extend in a direction C1 opposite to the direction C2 in which the elastic member 5b extends. Furthermore, the elastic member 5b is not in contact with the plate-shaped portion 102, and the capacitance value between the elastic member 5b and the plate-shaped portion 102 is 1.4 pF or more and 100 pF or less. Specifically, the distance between the elastic member 5b and the plate-shaped portion 102 is preferably 0.01 mm or more, and more preferably 0.1 mm or more for stability.

[0015] 1(b), a bent portion 52a is provided near the open end 50a of the elastic member 5a, and a bent portion 52b is provided near the open end 50b of the elastic member 5b. The bent portions 52a and 52b are provided so as to protrude toward the plate-shaped portion 102, and the elastic members 5a and 5b are configured to be deformable when a force is applied.

[0016] The length L1 and the length L2 can be set appropriately within the range in which the elastic members 5a and 5b can be installed, but from the viewpoint of the strength of the plate-shaped portion 101, it is preferable that the length L1 be 5 mm or more and 15 mm or less, and the length L2 be 30 mm or more and 50 mm or less.

[0017] Furthermore, the elastic members 5a and 5b are preferably provided by cutting and raising the container 2 or the lid 3 made of sheet metal, but the elastic members 5a and 5b may be provided to the container 2 or the lid 3 later.

[0018] To establish electrical continuity between the container 2 and the lid 3, the lid 3 can be fixed to the container 2 using, for example, screws (not shown). However, even when using screws to secure the container 2 and the lid 3, it is difficult to achieve perfect contact between them, and a gap may form between the container 2 and the lid 3. When a gap forms, an electric field resonance occurs with the screw position as a node. That is, when screws are provided at both ends of the container 2 and the lid 3, a resonance occurs at a frequency corresponding to a wavelength twice the distance between the screws. To suppress this resonance, electrical continuity between the container 2 and the lid 3 can be established at the position where the electric field strength is highest, i.e., the midpoint between the ends. By establishing electrical continuity at the midpoint, the resonance can be suppressed by shifting the frequency band to twice the frequency band.

[0019] Generally, when an elastic member is used to ensure electrical continuity, it is preferable that the length of the elastic member be longer to increase the strength of the elastic member. However, the inventors have confirmed that making the length of the elastic member too long increases inductance. Therefore, when the elastic member is made longer, the inductance increases and the resonance suppression effect decreases. Conversely, when the elastic member is made shorter, the inductance can be reduced compared to when the elastic member is made longer, but this is still insufficient. Therefore, the present invention prevents the deterioration of electrical characteristics due to increased inductance by capacitively connecting the elastic member.

[0020] The following will specifically explain the present invention using examples.

[0021] <Example> The conduction characteristics were obtained by simulation when the capacitance value of the structure 6 shown in Fig. 1 was changed. The transmission characteristics between the plate-like portion 101 and the plate-like portion 102 were calculated as the conduction characteristics. The elastic members 5a and 5b of the structure 6 were modeled as a parallel circuit with the inductance of the structure of the comparative example shown in Fig. 2, and capacitance was inserted in series with the inductance of the elastic member 5b.

[0022] The inductance of the structure in Fig. 2 will be described below. The structure in Fig. 2 has a length L1 of 10 mm, a length L2 of 41 mm, a conductor thickness of 0.6 mm, and an elastic member length of 40 mm and width of 1 mm. Furthermore, the bent portion of the elastic member was grounded to the plate-like portion 102 with a width of 1 mm x 0.6 mm, and the distance between the elastic member and the conductor surrounding the elastic member was 2.66 mm, with an inductance value of 19 nH.

[0023] The simulation results are shown in Figure 3. The transmission characteristics are values ​​at 800 MHz, and the closer to 0 on the vertical axis, the more transmission (conduction) there is, and conversely, when it is below 0, there is no transmission and it is difficult to conduct.

[0024] <Comparative Example> A comparative example will be described using Figure 2. Figure 2 differs from the example in that there is no elastic member extending in the opposite direction to elastic member 5. As mentioned above, the inductance value of elastic member 5 in Figure 2 is modeled as 19 nH. The results of the conduction characteristics are shown by the dotted line in Figure 3.

[0025] <Evaluation results> As shown in Figure 1, by providing the structure 6 and setting the capacitance value to 1.4 pF or more and 100 pF or less, it was possible to improve the conductivity that deteriorates due to increased inductance compared to when only the elastic member 5 is provided. Furthermore, by setting the capacitance value to 1.8 pF or more and 4 pF or less, it was possible to significantly improve the conductivity.

[0026] In this embodiment, when forming a capacitance, the elastic member 5b may be formed so as to increase the opposing area between the elastic member 5b and the plate-like portion 102, or a dielectric member 7 made of a dielectric material may be sandwiched between the elastic member 5b and the plate-like portion 102 as shown in FIG. 4. In the configuration in which the dielectric member 7 is sandwiched, it is possible to form a capacitance even if the opposing area between the elastic member 5b and the plate-like portion 102 is small. The dielectric member 7 may be, for example, a tape or similar material. Incidentally, if an attempt is made to achieve 1.4 pF with air without sandwiching the dielectric member 7, a 2 mm 2 With an opposing area of ​​102 mm, the distance between the opposing surfaces would be 0.01 mm, which is not realistic because it would require forming the plate-like portion 102 and the elastic member 5b with great precision. However, by providing the dielectric member 7, it is possible to achieve such a distance.

[0027] In this embodiment, an example has been described in which an elastic member is used as the second conductive member, but it may simply be provided as a conductive plate.

[0028] As shown in FIG. 5, elastic members 5a and 5b may be disposed opposite each other, with at least a portion of elastic member 5a aligned with elastic member 5b in direction C3 intersecting with direction C1 or direction C2.

[0029] Furthermore, as mentioned above, when screws (not shown) are provided at both ends of the container 2 and the lid 3, a resonance phenomenon occurs at a frequency corresponding to a wavelength twice the distance L between the screws electrically connecting the container 2 and the lid 3. To suppress this resonance, it is preferable to establish electrical continuity between the container 2 and the lid 3 at the position where the electric field strength is highest, i.e., the center position of the ends. That is, it is preferable to position the elastic member 5b near the center between the two adjacent screws (connection portions) electrically connecting the container 2 and the lid 3. Furthermore, it is preferable to position the elastic member 5b within ±L / 4 of the center position where the electric field strength is highest, and more preferably at the center between the two adjacent screws. That is, it can be said that the elastic member 5b is preferably positioned within a range of −L / 4 or more and L / 4 or less from the elastic member 5a.

[0030] Second Embodiment FIG. 6 is an explanatory diagram of an image forming apparatus 600 as an example of an apparatus to which the housing 1 using the structure 6 of the first embodiment can be applied.

[0031] The image forming apparatus 600 is, for example, an electrophotographic laser beam printer, and includes a housing 1, an exterior cover 601, an image forming unit 610, and an image reading unit 620.

[0032] The image reading unit 620 is a device that reads an image of a set document. The image forming unit 610 forms an image on a sheet based on image data. The sheet refers to a recording medium including plain paper, special paper such as coated paper, envelopes, paper such as index paper, plastic film for overhead projectors, and cloth.

[0033] FIG. 7 is a schematic diagram of the image forming unit 610 shown in FIG. 6. The image forming unit 610 is controlled by a control device provided inside the housing 1. As shown in FIG. 7, the image forming unit 610 includes an electrophotographic image forming unit PU and a fixing device 107. When an instruction to start an image forming operation is given, the photosensitive drum 101, which is a photosensitive member, rotates, and the surface of the photosensitive drum 101 is uniformly charged by the charging device 102. Then, the exposure device 103 modulates and outputs laser light based on image data transmitted from the image reading unit 620 or an external computer, and scans the surface of the photosensitive drum 101 to form an electrostatic latent image. This electrostatic latent image is developed into a toner image by toner supplied from the developing device 104.

[0034] In parallel with this image forming operation, a feeding operation is performed to feed sheets loaded in a cassette or manual feed tray (not shown) toward the image forming unit 610. The fed sheets are transported in accordance with the progress of the image forming operation by the image forming unit PU. The toner image carried on the photosensitive drum 101 is then transferred to the sheet by the transfer roller 5. Any toner remaining on the photosensitive drum 101 after the toner image transfer is collected by the cleaning device 106. The sheet onto which the toner image has been transferred is passed to the fixing device 107, where it is sandwiched between a pair of rollers and heated and pressurized. The sheet, on which the toner has melted and adhered to the sheet and the image has been fixed, is discharged outside the machine by a pair of discharge rollers. In the case of double-sided printing, the sheet is conveyed in an inverted state by the reverse conveying unit 108, and after the image is formed on the back side by the image forming unit 610, it is discharged outside the machine.

[0035] The image forming unit 610 is an example of an image forming means capable of forming an image on a sheet as a recording medium, and instead of the above-mentioned direct transfer method, an intermediate transfer method including an intermediate transfer body may be used, or other mechanisms such as an inkjet method may be used.

[0036] The above-described embodiments can be modified as appropriate without departing from the technical concept. For example, in the previous embodiment, the container constituting the housing has a first plate-shaped portion and the lid has a second plate-shaped portion, but each may have an opposite plate-shaped portion. Also, in the previous embodiment, an example of a housing in which electrical continuity is established between the container and the lid has been described. However, the present invention can be applied to any structure in which electrical continuity is established between members each having overlapping plate-shaped portions.

[0037] Furthermore, the above-described multiple embodiments may be combined with each other. Furthermore, some features of at least one embodiment may be deleted or replaced. Furthermore, new features may be added to at least one embodiment.

[0038] The disclosure of this specification includes not only what is explicitly described in this specification, but also all matters that can be understood from this specification and the drawings attached to this specification.

[0039] Furthermore, the disclosure of this specification includes the complement of each individual concept described in this specification. In other words, if this specification contains a statement that "A is greater than B," for example, it can be said that this specification discloses "A is not greater than B," even if it omits the statement that "A is not greater than B." This is because when a statement that "A is greater than B" is made, it is assumed that the case in which "A is not greater than B" is taken into consideration.

[0040] The disclosure of the present invention is shown below.

[0041] (Item 1) A structure including a first plate-shaped portion having electrical conductivity and a second plate-shaped portion having electrical conductivity, a first conductive member and a second conductive member extending from the first plate-shaped portion and having open ends; In a state in which the first plate-shaped portion and the second plate-shaped portion are joined together, the first conductive member is provided so as to be in contact with the second plate-shaped portion, the second conductive member is provided so as not to come into contact with the second plate-shaped portion, A structure characterized in that the capacitance value between the second conductive member and the second plate-shaped portion is 1.4 pF or more and 100 pF or less.

[0042] (Item 2) Item 2. The structure according to item 1, wherein the capacitance value is 1.8 pF or more and 4 pF or less.

[0043] (Item 3) 3. The structure according to item 1 or 2, wherein a dielectric member is disposed between the second conductive member and the second plate-shaped portion.

[0044] (Item 4) 4. The structure according to any one of items 1 to 3, wherein the second conductive member and the second plate-shaped portion are spaced apart by 0.01 mm or more.

[0045] (Item 5) The structure described in any one of items 1 to 4, characterized in that the first conductive member is provided between two adjacent connection portions where the first plate-shaped portion and the second plate-shaped portion are connected.

[0046] (Item 6) Item 6. The structure according to item 5, characterized in that, when the length between two adjacent points where the first plate-shaped portion and the second plate-shaped portion are connected is L, the distance between the open end of the first conductive member and the open end of the second conductive member is located at a position that is not less than -L / 4 and not more than L / 4.

[0047] (Item 7) 7. The structure according to any one of items 1 to 6, wherein the first conductive member is made of an elastic member.

[0048] (Item 8) the first conductive member extends in a first direction, and the second conductive member extends in a second direction opposite to the first direction; 8. The structure according to any one of items 1 to 7, wherein the first conductive member and the second conductive member are arranged so that a portion of each of the first conductive member and the second conductive member is parallel to each other.

[0049] (Item 9) The first plate-shaped portion and the second plate-shaped portion of the structure described in any one of items 1 to 8 are either a container or a lid that covers an opening of the container.

[0050] (Item 10) Item 10. The housing according to item 9, characterized in that a control device for controlling electronic devices is provided inside.

[0051] (Item 11) an image forming unit that forms an image on a sheet; Item 11. An image forming apparatus characterized in that the image forming unit is controlled by a control device provided inside the housing according to item 10. [Explanation of symbols]

[0052] 5a Elastic member (first conductive member) 5b Elastic member (second conductive member) 6 Structure 7 Dielectrics 101 plate-shaped portion (first plate-shaped portion) 102 plate-shaped portion (second plate-shaped portion) C1 1st direction C2 2nd direction C3 3rd direction

Claims

1. A structure including a first plate-shaped portion having electrical conductivity and a second plate-shaped portion having electrical conductivity, a first conductive member and a second conductive member extending from the first plate-shaped portion and having open ends; In a state in which the first plate-shaped portion and the second plate-shaped portion are joined together, the first conductive member is provided so as to be in contact with the second plate-shaped portion, the second conductive member is provided so as not to come into contact with the second plate-shaped portion, A structure characterized in that the capacitance value between the second conductive member and the second plate-shaped portion is 1.4 pF or more and 100 pF or less.

2. 2. The structure of claim 1, wherein the capacitance value is greater than or equal to 1.8 pF and less than or equal to 4 pF.

3. The structure according to claim 1 , wherein a dielectric member is disposed between the second conductive member and the second plate-shaped portion.

4. The structure according to claim 1 , wherein the second conductive member and the second plate-shaped portion are spaced apart by 0.01 mm or more.

5. The structure according to claim 1 , wherein the first conductive member is provided between two adjacent connection portions where the first plate-shaped portion and the second plate-shaped portion are connected.

6. The structure described in claim 5, characterized in that, when the length between two adjacent points where the first plate-shaped portion and the second plate-shaped portion are connected is L, the distance between the open end of the first conductive member and the open end of the second conductive member is located at a position that is greater than or equal to -L / 4 and less than or equal to L / 4.

7. The structure according to claim 1 , wherein the first conductive member is made of an elastic material.

8. the first conductive member extends in a first direction, and the second conductive member extends in a second direction opposite to the first direction; The structure according to claim 1 , wherein the first conductive member and the second conductive member are arranged so that a portion of each of the first conductive member and the second conductive member is parallel to each other.

9. 9. A housing, wherein the first plate-shaped portion and the second plate-shaped portion of the structure according to claim 1 are either a container or a lid that covers an opening of the container.

10. 10. The housing according to claim 9, wherein a control device for controlling electronic equipment is provided inside the housing.

11. an image forming unit that forms an image on a sheet; 11. An image forming apparatus, wherein the image forming unit is controlled by a control device provided inside the housing according to claim 10.

Images