Cable connection structure

Abstract

The objective is to provide a cable connection structure that can protect a conductor with relatively low durability when multiple conductors are connected to an electronic component. [Solution] The cable connection structure is composed of an electronic component having at least a first electrode and a second electrode on its electrode-forming surface, and a cable having at least a first conductor and a second conductor in its covering material. The tip of the first conductor extends from the front end of the covering material and is connected to the first electrode, and the tip of the second conductor extends from the front end and is connected to the second electrode. The length of the first conductor between the front end and the first electrode is shorter than the length of the second conductor between the front end and the second electrode.

Description

Technical Field

[0001] The present invention relates to a cable connection structure in which a cable is connected to an electronic component such as an imaging device.

Background Art

[0002] As an imaging unit used in an endoscope for industrial use or the like, a cable connection structure in which a cable for transmitting driving power, imaging signals, etc. is connected to an imaging device such as a CMOS or a CCD is used.

[0003] As such a cable connection structure, one in which a coaxial cable or the like is connected to an electrode formed on the back surface of the imaging surface of an imaging device is known (for example, Patent Documents 1 and 2).

[0004] Endoscopes used for observing narrow places are required to have a smaller diameter, and the cable connection structure used in endoscopes is also required to be miniaturized, and a cable with a smaller diameter is used for the cable connected to the imaging device.

[0005] Although a conductor having a smaller diameter is used for the cable, the conductor having a smaller diameter may be disconnected or deformed due to a load such as tension.

[0006] Conductors for mainly supplying driving power, transmitting imaging signals, and grounding are respectively connected to the electrodes of the imaging device. However, since the specific mode of each conductor is determined according to the purpose, a difference in durability against load often occurs between the conductors.

[0007] Generally, conductors used for supplying driving power and grounding need to have a smaller conductor resistance than conductors used for transmitting imaging signals, and the conductor diameter is often set thicker compared to conductors used for transmitting imaging signals.

[0008] As a result, the conductor used for transmitting imaging signals becomes thinner than the conductors used for supplying driving power and grounding, and the durability against load becomes relatively low.

[0009] Therefore, conventional cable connection structures have the problem that when a cable is suddenly pulled, the conductor, which has relatively low load resistance, is prone to breaking.

[0010] Even if the wire doesn't break, the load can deform the conductor, potentially negatively impacting signal transmission. [Prior art documents] [Patent Documents]

[0011] [Patent Document 1] Japanese Patent Publication No. 2019-180603 [Patent Document 2] Japanese Patent Publication No. 2022-157202 [Disclosure of the Invention] [Problems that the invention aims to solve]

[0012] The object of the present invention is to provide a cable connection structure that can protect a conductor with relatively low durability when multiple conductors are connected to an electronic component. [Means for solving the problem]

[0013] The inventors, after diligently studying the structure of cable connection structures, found that the above problems could be solved by adopting the following structure.

[0014] (1) An electronic component having at least a first electrode and a second electrode on its electrode-forming surface, A cable connection structure having a cable comprising at least a first conductor and a second conductor within a covering material, The tip of the first conductor extends from the front end of the covering material and is connected to the first electrode. The tip of the second conductor extends from the front end and is connected to the second electrode. A cable connection structure characterized in that the length of the first conductor between the front end and the first electrode is shorter than the length of the second conductor between the front end and the second electrode. (2) The cable connection structure according to (1) above, characterized in that the central axis of the cable does not coincide with the central axis of the electronic component, and the distance between the central axis of the cable and the first electrode is shorter than the distance between the central axis of the cable and the second electrode. (3) The cable connection structure according to (1) or (2) above, characterized in that the first conductor is connected to the first electrode so as to be substantially perpendicular to the electrode forming surface, and the second conductor is connected to the second electrode so as to be curved between the electrode forming surface and the front end. (4) The cable connection structure according to any one of (1) to (3) above, characterized in that the second conductor is a single-core conductor strand. (5) The cable connection structure according to any one of (1) to (4) above, characterized in that the cable is a coaxial cable composed of a central conductor, a dielectric, an outer conductor, and an outer sheath, wherein the outer conductor is used as the first conductor, the central conductor as the second conductor, and the outer sheath as the covering material. (6) The cable connection structure according to (5) above, characterized in that the outer conductor has a braided structure, and the central conductor covered with the dielectric is drawn out through the mesh of the braided structure extending from the front end, thereby causing the tip of the second conductor to extend from the front end. (7) The cable is a composite cable in which a shielded wire, composed of a central conductor, a dielectric, and a shielding layer, and a metal conductor are all covered together with the covering material. A cable connection structure according to any one of (1) to (4) above, characterized in that the shield layer and the metal conductor are in electrical contact, and the metal conductor is used as the first conductor and the central conductor as the second conductor. (8) The shield layer is a metal plating layer formed on the surface of the dielectric, and the cable connection structure according to (7) above is characterized in that. (9) The shield layer is a film-like member having a metal layer covering the surface of the dielectric, and the cable connection structure according to (7) above is characterized in that. (10) An electronic component having at least a first electrode and a second electrode on an electrode formation surface, A cable connection structure composed of a cable having at least a first conductor and a second conductor in a covering material, The first conductor is electrically connected to the first electrode via a third conductor, The tip of the second conductor extends from the front end of the covering material and is connected to the second electrode A cable connection structure characterized in that the length of the third conductor between the front end and the first electrode is shorter than the length of the second conductor between the front end and the second electrode. (11) The central axis of the cable does not coincide with the central axis of the electronic component, and the distance between the central axis of the cable and the first electrode is shorter than the distance between the central axis of the cable and the second electrode, and the cable connection structure according to (10) above is characterized in that. (12) The third conductor is connected to the first electrode so as to be substantially perpendicular to the electrode formation surface, and the second conductor is connected to the second electrode so as to be curved between the electrode formation surface and the front end, and the cable connection structure according to (10) or (11) above is characterized in that. (13) The second conductor is a single-core conductor strand, and the cable connection structure according to any one of (10) to (12) above is characterized in that. (14) The cable is a coaxial cable composed of a central conductor, a dielectric, an outer conductor, and an outer sheath. A cable connection structure according to any one of (10) to (13) above, characterized in that the outer conductor is used as the first conductor, the central conductor as the second conductor, and the sheath as the covering material. (15) The cable connection structure according to (14) above, characterized in that the outer conductor is composed of a metal plating layer, a metal foil, or a resin-metal composite film. [Effects of the Invention]

[0015] According to the present invention, a cable connection structure is provided in which deformation and disconnection of conductors connected to electronic components are suppressed. [Brief explanation of the drawing]

[0016] [Figure 1] This is the basic structure of the present invention. [Figure 2] This invention utilizes a coaxial cable. [Figure 3] This invention utilizes two coaxial cables. [Figure 4] This invention utilizes a third conductor. [Figure 5] This is an example of a composite cable used in the present invention. [Figure 6] This invention utilizes a composite cable. [Modes for carrying out the invention]

[0017] The cable connection structure 1 of the present invention will be described below with reference to the drawings. However, the technical scope of the present invention is not limited to the following description or drawings.

[0018] [Basic configuration] As shown in Figure 1, the cable connection structure 1 of the present invention is composed of an electronic component 10 and a cable 20.

[0019] Specific examples of the electronic component 10 used in the present invention include image sensors such as CMOS and CCD, and the base end of the electronic component 10 is an electrode-forming surface 12 on which electrodes 14 used for supplying power and signals to the electronic component 10 and for grounding are formed.

[0020] Although the electronic component 10 shown in Figure 1 is rectangular, the specific shape of the electronic component 10 is not particularly limited, and it may be cylindrical or the like as long as it has an electrode-forming surface 12 on which the electrodes 14 are formed.

[0021] The size of the electronic component 10 used in the present invention is appropriately set according to the endoscope or the like in which the cable connection structure 1 of the present invention is used. However, in the case of CMOS, CCD, etc., a component with a width of about 0.5 to 2 mm, a height of about 0.5 to 2 mm, and a length of about 0.2 to 2 mm is used.

[0022] The electrode-forming surface 12 is provided with at least a first electrode 14a and a second electrode 14b as electrodes 14, but the number of electrodes 14 is determined according to the specifications of the electronic component 10, and the electrode-forming surface 12 may be provided with three or more electrodes 14.

[0023] The cable 20 used in the present invention has a configuration comprising at least a first conductor 22a and a second conductor 22b within a sheathing material 28, the tip of the first conductor 22a extending from the front end E of the sheathing material 28 and connected to the first electrode 14a, and the tip of the second conductor 22b extending from the front end E and connected to the second electrode 14b.

[0024] If necessary, the first conductor 22a and the second conductor 22b extending from the front end E may be partially covered by the insulating coatings 24a and 24b.

[0025] At this time, the connection is made such that the length of the first conductor 22a between the front end E and the first electrode 14a is shorter than the length of the second conductor 22b between the front end E and the second electrode 14b.

[0026] With this structure, when the cable 20 is pulled in the longitudinal direction, the tensile load is concentrated on the first conductor 22a, which has a shorter distance between the front end E and the first electrode 14a compared to the second conductor 22b.

[0027] By implementing the present invention with the conductor to be avoided under tensile load designated as the second conductor 22b, and the conductor that can tolerate tensile load compared to the second conductor 22b designated as the first conductor 22a, the load on the second conductor 22b during tension is suppressed, contributing to improved durability of the cable connection structure 1.

[0028] The conductor 22 can be connected to the electrode 14 by using various electrical connection methods, such as soldering or conductive adhesive, which can be selected as appropriate.

[0029] When connecting the cable 20 to the electronic component 10, it is preferable not to align the central axis X2 of the cable 20 with the central axis X1 of the electronic component 10, as shown in Figure 1, and to make the distance between the central axis X2 of the cable 20 and the first electrode 14a shorter than the distance between the central axis X2 of the cable 20 and the second electrode 14b.

[0030] By adopting this structure, it is possible to create a difference between the length of the first conductor 22a between the front end E and the first electrode 14a, and the length of the second conductor 22b between the front end E and the second electrode 14b.

[0031] In addition, as shown in Figure 1, it is preferable that the first conductor 22a is connected to the first electrode 14a so as to be substantially perpendicular to the electrode forming surface 12, and the second conductor 22b is connected to the second electrode 14b so as to be curved between the electrode forming surface 12 and the front end E.

[0032] This structure ensures that the distance between the central axis X2 of the cable 20 and the first electrode 14a is shorter than the distance between the central axis X2 of the cable 20 and the second electrode 14b.

[0033] In addition, by connecting the second conductor 22b to the second electrode 14b so as to be curved between the electrode forming surface 12 and the front end E, it contributes to suppressing the load on the second conductor 22b during tension.

[0034] The first conductor 22a and the second conductor 22b can be appropriately selected from among the conductor configurations used in various insulated wires, and single-core conductors, stranded conductors, bundled stranded conductors, etc., can be used.

[0035] In this invention, single-core conductor strands are preferably used as the second conductor 22b.

[0036] When connecting to the second electrode 14b, if the length of the second conductor 22b between the front end E and the second electrode 14b is made longer than that of the first conductor 22a, and the conductor is curved, then a single-core conductor strand, which has superior shape retention in a curved state compared to a stranded conductor, can be preferably used.

[0037] In addition, single-core conductor strands contribute to improving the durability of the second conductor 22b against tension, and can also be used favorably from the viewpoint of reducing the diameter of the cable 20, as they allow for a smaller outer diameter compared to stranded conductors having the same conductor cross-sectional area.

[0038] The cable 20 used in the present invention can be appropriately selected from various types of cables, as long as it has conductors that can be used as the first conductor 22a and the second conductor 22b provided within the covering material 28.

[0039] The present invention is provided in various embodiments depending on the cable 20 used, as described below. The present invention will be described below with reference to the drawings for each embodiment.

[0040] [First Embodiment] An example of a cable connection structure 1 according to the first embodiment is the one shown in Figure 2, in which a coaxial cable 120 is used as the cable 20.

[0041] The coaxial cable 120 is composed of a central conductor 122b, a dielectric 124, an outer conductor 122a, and an outer sheath 128. The outer conductor 122a can be used as the first conductor 22a, the central conductor 122b as the second conductor 22b, and the outer sheath 128 as the covering material 28.

[0042] A small-diameter coaxial cable 120 can be used, contributing to the miniaturization of the cable connection structure 1.

[0043] The specific dimensions of the coaxial cable 120 can be appropriately selected according to the electronic components 10 used. However, when using CMOS, CCD, etc., as mentioned above, the outer diameter of the center conductor 122b should be set to approximately 42AWG (American Wire Gauge) to 48AWG, and the outer diameter of the sheath 128 should be set to approximately 0.1 to 0.5 mm.

[0044] As the outer conductor 122a, a braided structure using individual conductor wires, a winding structure, a dielectric 124 with a metal plating layer formed on its surface, or a dielectric 124 covered with a film-like member having a metal layer can be used.

[0045] Examples of film-like members having a metal layer include metal foil and resin-metal laminated films.

[0046] Considering that the first conductor 22a will be connected to the first electrode 14a, a braided structure with excellent strength and shape retention is preferably used.

[0047] When using a braided outer conductor 122a, it is preferable that the area near the tip of the coaxial cable 120 connected to the electronic component 10 is configured such that the central conductor 122b, covered with a dielectric 124, is drawn out through the braid of the braided outer conductor 122a extending from the front end E of the outer sheath 128, as shown in Figure 2.

[0048] By configuring the tip of the coaxial cable 120 in this manner, the braided structure of the outer conductor 122a can be maintained all the way to its tip, making it easier to connect to the first electrode 14a and also contributing to improved durability of the first conductor 22a against tension.

[0049] Since the braided outer conductor 122a is composed of conductor strands that are inclined with respect to the tensile direction, the load under tension is mitigated, contributing to improved durability when used as the first conductor 22a.

[0050] If the coaxial cable 120 consists only of the first electrode 14a and the second electrode 14b, one cable 120 is used. If there are also the third electrode 14c and the fourth electrode 14d, two cables 120 are used to construct the cable connection structure 1, as shown in Figure 3. If Figure 2 is a side view of the cable connection structure 1, then Figure 3(a) corresponds to a top view of the cable connection structure 1 shown in Figure 2, and Figure 3(b) corresponds to a bottom view.

[0051] Furthermore, when using two coaxial cables 120, the central conductor 122b covered with dielectric 124 may be crossed between the front end E and the electrode formation surface 12 as shown in Figure 3(c), if necessary.

[0052] [Second Embodiment] As a cable connection structure 1 according to the second embodiment, an example is shown in Figure 4, in which a coaxial cable 120 is used as the cable 20, and a third conductor 22c is used in combination.

[0053] Considering the flexibility and miniaturization of the coaxial cable 120, the outer conductor 122a can preferably be a horizontally wound structure, a metal-plated layer, or a film-like member having a metal layer. However, if these forms are selected for the outer conductor 122a, it becomes difficult to connect it directly to the first electrode 14a.

[0054] In particular, thin-film external conductors 122a, such as metal plating layers, metal foils, and resin-metal composite films, are useful in terms of reducing the diameter of the coaxial cable 120, but it is extremely difficult to connect them directly to the electrodes 14 provided on the electrode-forming surface 12 of the electronic component 10.

[0055] If it is difficult to directly connect the first conductor 22a to the first electrode 14a, as shown in Figure 4, a third conductor 22c, which can be easily connected to the first electrode 14a, can be connected to the first conductor 22a, and the first conductor 22a can be electrically connected to the first electrode 14a via the third conductor 22c.

[0056] When using the third conductor 22c, the length of the third conductor 322c between the front end E of the covering material 28 and the first electrode 14a is made shorter than the length of the second conductor 22b between the front end E and the second electrode 14b, similar to when the first conductor 22a is connected to the first electrode 14a.

[0057] Similarly, it is preferable that the third conductor 22c is connected to the first electrode 14a so as to be substantially perpendicular to the electrode forming surface 12, and the second conductor 22b is connected to the second electrode 14b so as to be curved between the electrode forming surface 12 and the front end E.

[0058] The third conductor 22c can be a single-core conductor, a stranded conductor, a bundled stranded conductor, or any other conductor composed of individual wires. Figure 4 shows an example where a single-core conductor is used as the third conductor 22c.

[0059] Furthermore, circuit components can be used in which conductive paths are formed on a resin substrate using metal plating, conductive adhesive, metal foil, etc., and the conductive paths of the circuit components can be used as the third conductor 22c.

[0060] [Third Embodiment] As a cable connection structure 1 according to the third embodiment, an example shown in Figure 5 is used in which a composite cable 220 is used as the cable 20, in which a shielded wire 221 composed of a central conductor 222b, a dielectric 224, and a shielding layer 226, and a metal conductor 222a are all covered together with a covering material 228.

[0061] In the composite cable 220, the metal conductor 222a may be twisted with the shield wire 221 or attached vertically.

[0062] Furthermore, multiple shield wires 221 and metal conductors 222a may be used. Figure 4 shows a composite cable 220 constructed using three shield wires 221 and one metal conductor 222a.

[0063] When this composite cable 220 is used as cable 20, the shield layer 226 and the metal conductor 222a are in electrical contact, the metal conductor 222a is used as the first conductor 22a, and the central conductor 222b is used as the second conductor 22b, and are connected to the first electrode 14a and the second electrode 14b, respectively, as shown in Figure 5.

[0064] This composite cable 220 contributes to reducing the diameter of the cable 20 when it is necessary to use a cable 20 having a number of electrodes 14 on the electrode forming surface 12 and having conductors corresponding to the number of electrodes 14.

[0065] The specific dimensions of each element constituting the composite cable 220 can be appropriately selected according to the electronic components 10 used, but when using CMOS, CCD, etc. as described above, The outer diameter of the central conductor 222b of the shielded wire 221 is set to approximately 0.03 to 0.1 mm, and the outer diameter of the shielding layer 226 is set to approximately 0.05 to 0.3 mm.

[0066] Similarly, the outer diameter of the metal conductor 222a is set to approximately 0.03 to 0.1 mm, and the outer diameter of the covering material 228 is set to approximately 0.2 to 1 mm.

[0067] The metal conductor 222a can be a single-core conductor, a stranded conductor, a bundled stranded conductor, or any other conductor composed of individual wires. Figures 5 and 6 show an embodiment in which a single-core conductor is used as the metal conductor 222a.

[0068] From the standpoint of reducing the diameter of the composite cable 220, it is preferable to use a shielding layer 226 in which a metal plating layer is formed on the surface of the dielectric 224, or in which the dielectric 224 is covered with a film-like member having a metal layer.

[0069] Thin-film shielding layers 226, such as metal plating layers, metal foils, and resin-metal composite films, are useful in terms of reducing the diameter of the composite cable 220, but it is difficult to connect them directly to the electrodes 14 provided on the electrode formation surface 12 of the electronic component 10.

[0070] A composite cable 220 is formed including a metal conductor 222a which becomes the first conductor 22a connected to the first electrode 14a, and by making the shield layer 226 and the metal conductor 222a electrically contact, the shield layer 226 can be used as part of the conductive path connected to the electronic component 10.

[0071] Considering that the metal conductor 222a is electrically connected to the shield layer 226, it is preferable to select an electrode that functions as the ground terminal of the electronic component 10 as the first electrode 14a to which the metal conductor 222a is connected.

[0072] If the first electrode 14a functions as the grounding terminal of the electronic component 10, a grounding current flows to the shielding layer 226 via the metal conductor 222a, which also contributes to improving the shielding effect of the composite cable 220.

[0073] In addition, the shielded wire 221 included in the composite cable 220 can be expected to have an electromagnetic interference suppression effect when used as a power line.

[0074] From the viewpoint of improving the shielding effect of the composite cable 220, it is desirable that electrical contact be reliably made between the metal conductor 222a and the shield layer 226, and between the shield layers 226 themselves, and it is preferable that the shielded wire 221 is not provided with an outer sheath.

[0075] The basic configuration and embodiments of the cable connection structure 1 of the present invention have been described above, but the specific embodiments of the present invention are not limited to these and can be appropriately modified and implemented within the scope of the technical idea of ​​the present invention.

[0076] The electronic component 10 can be an image sensor such as a CMOS or CCD, or any component equipped with multiple electrodes 14 on an electrode formation surface 12. Printed circuit boards, CSPs (Chip Size Packages), MIDs (Molded Interconnected Devices) can also be used as electronic components 10 in this invention.

[0077] The specific form of the cable 20 can be appropriately selected and used in accordance with the electronic components 10 being used.

[0078] Furthermore, in order to increase the connection strength between the electronic component 10 and the cable 20, at least a portion of the area between the front end E and the electrode forming surface 12 may be sealed with a resin material or the like, if necessary. [Industrial applicability]

[0079] The cable connection structure of the present invention can be preferably used in situations where a thin cable is connected to small electronic components, such as small imaging units used in endoscopes, various sensors, electrical connectors, and circuit components. [Explanation of Symbols]

[0080] 1. Cable connection structure 10 Electronic Components 12 Electrode formation surface 14 electrodes 14a 1st electrode 14b 2nd electrode 20 Cables 22 Conductors 22a First conductor 22b Second conductor 22c Third conductor 24, 24a, 24b Insulation coating 28 Covering material E Front end of covering material 120 Coaxial Cable 122a Outer conductor 122b Center conductor 124 Dielectrics 128 Outer cover 220 composite cable 221 Shielded Cable 222a Metal conductor 222b Center conductor 224 Dielectrics 226 Shield layer 228 Covering material X1: The central axis of electronic components X2 Cable Central Axis

Claims

1. An electronic component having at least a first electrode and a second electrode on its electrode-forming surface, A cable connection structure having a cable comprising at least a first conductor and a second conductor within a covering material, The tip of the first conductor extends from the front end of the covering material and is connected to the first electrode. The tip of the second conductor extends from the front end and is connected to the second electrode. A cable connection structure characterized in that the length of the first conductor between the front end and the first electrode is shorter than the length of the second conductor between the front end and the second electrode.

2. The cable connection structure according to claim 1, characterized in that the central axis of the cable does not coincide with the central axis of the electronic component, and the distance between the central axis of the cable and the first electrode is shorter than the distance between the central axis of the cable and the second electrode.

3. The cable connection structure according to claim 2, characterized in that the first conductor is connected to the first electrode so as to be substantially perpendicular to the electrode forming surface, and the second conductor is connected to the second electrode so as to be curved between the electrode forming surface and the front end.

4. The cable connection structure according to claim 3, characterized in that the second conductor is a single-core conductor strand.

5. The cable is a coaxial cable composed of a central conductor, a dielectric, an outer conductor, and an outer sheath. A cable connection structure according to any one of claims 1 to 4, characterized in that the outer conductor is used as the first conductor, the central conductor as the second conductor, and the sheath as the covering material.

6. The cable connection structure according to claim 5, characterized in that the outer conductor has a braided structure, and the central conductor covered with the dielectric is drawn out through the mesh of the braided structure extending from the front end, thereby causing the tip of the second conductor to extend from the front end.

7. The cable is a composite cable in which a shielded wire, composed of a central conductor, a dielectric, and a shielding layer, and a metal conductor are all covered together with the covering material. The cable connection structure according to any one of claims 1 to 4, characterized in that the shield layer and the metal conductor are in electrical contact, and the metal conductor is used as the first conductor and the central conductor as the second conductor.

8. The cable connection structure according to claim 7, characterized in that the shielding layer is a metal plating layer formed on the surface of the dielectric.

9. The cable connection structure according to claim 7, characterized in that the shielding layer is a film-like member having a metal layer covering the surface of the dielectric.

10. An electronic component having at least a first electrode and a second electrode on its electrode-forming surface, A cable connection structure comprising a cable having at least a first conductor and a second conductor inside a covering material, The first conductor is electrically connected to the first electrode via the third conductor. The tip of the second conductor extends from the front end of the covering material and is connected to the second electrode. A cable connection structure characterized in that the length of the third conductor between the front end and the first electrode is shorter than the length of the second conductor between the front end and the second electrode.

11. The cable connection structure according to claim 10, characterized in that the central axis of the cable does not coincide with the central axis of the electronic component, and the distance between the central axis of the cable and the first electrode is shorter than the distance between the central axis of the cable and the second electrode.

12. The cable connection structure according to claim 11, characterized in that the third conductor is connected to the first electrode so as to be substantially perpendicular to the electrode forming surface, and the second conductor is connected to the second electrode so as to be curved between the electrode forming surface and the front end.

13. The cable connection structure according to claim 12, characterized in that the second conductor is a single-core conductor strand.

14. The cable is a coaxial cable composed of a central conductor, a dielectric, an outer conductor, and an outer sheath. A cable connection structure according to any one of claims 10 to 13, characterized in that the outer conductor is used as the first conductor, the central conductor as the second conductor, and the sheath as the covering material.

15. The cable connection structure according to claim 14, characterized in that the outer conductor is composed of a metal plating layer, a metal foil, or a resin-metal composite film.

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