Attachment structure of image forming apparatus

Abstract

The invention relates to an attachment structure of an imaging device. An attachment structure of an imaging device includes an imaging device and a housing that accommodates at least a portion of the imaging device. The imaging device includes forward-facing and laterally outward-facing lenses. The housing includes a circumferential wall disposed around the lens. The circumferential wall includes a front wall disposed forward of an optical axis of the lens and a rear wall disposed rearward of the optical axis of the lens. In a case where a direction parallel to an optical axis of the lens and traveling forward and laterally outward is defined as an outer direction and a tip side in the outer direction is defined as an outer side, an outer tip of the front wall is disposed on an outer side with respect to an outer tip of the rear wall in a plan view.

Description

Technical Field

[0001] The present invention relates to an attachment structure of an imaging device. Background Art

[0002] In recent years, efforts have been actively made to provide access to sustainable transportation systems that take into account the vulnerability of people among traffic participants. To achieve this, research and development to further improve traffic safety and convenience by developing preventive safety technologies is attracting attention.

[0003] For example, JP2022-39110A discloses a vehicle including a pair of left and right roof camera units mounted on a roof panel. The roof camera unit described in JP2022-39110A includes a telephoto camera unit and a wide-angle camera unit (imaging device), and a cover portion (housing) that covers the telephoto camera unit and the wide-angle camera unit from above.

[0004] When the imaging device is positioned outside the vehicle, as in JP2022-39110A, the housing must be provided with a circumferential wall surrounding the lens of the imaging device to protect it. In this case, the traveling wind generated by the vehicle's movement creates a vortex at the front of the circumferential wall, which then strikes the rear of the circumferential wall. This fluctuation in air pressure causes air vibrations, generating so-called wind noise. This wind noise resonates and is amplified within the housing, potentially causing discomfort to occupants. Summary of the Invention

[0005] In view of the above background, an object of the present invention is to provide an attachment structure for an imaging device that can suppress the generation of wind noise caused by traveling wind. This will ultimately contribute to the development of a sustainable transportation system.

[0006] To achieve such an object, one aspect of the present invention provides an attachment structure 10, 100, 200, 300 for an imaging device, the attachment structure for the imaging device including: an imaging device 12 mounted on a roof 2 of a vehicle 1; a housing 13 accommodating at least a portion of the imaging device, wherein the imaging device includes a lens 15 facing forward and laterally outward of the vehicle, the housing including a circumferential wall 21, 201, 301 arranged around the lens, the circumferential wall including: a front wall 29, 202, 303 arranged forward of an optical axis A of the lens in a plan view; and a rear wall 30, 203, 302 arranged rearward of the optical axis of the lens in a plan view, with an outboard end 29A, 202A, 303A of the front wall arranged outward relative to an outboard end 30A, 203A, 302A of the rear wall in a plan view, with a direction parallel to the optical axis of the lens and proceeding toward the forward and laterally outward of the vehicle defined as an outboard direction and a terminal side in the outboard direction defined as an outboard side.

[0007] According to this aspect, even if an eddy flow is generated at the front wall of the circumferential wall by the traveling wind, the eddy flow is less likely to hit the rear wall of the circumferential wall. Therefore, the generation of wind noise caused by the traveling wind can be suppressed.

[0008] In the above aspect, preferably, the front wall is provided with protrusions 31 , 101 protruding toward the outside.

[0009] According to this aspect, the outer end of the front wall protrudes significantly outward relative to the outer end of the rear wall. Therefore, even if an eddy current is generated at the front wall of the circumferential wall by the traveling wind, the eddy current is less likely to strike the rear wall of the circumferential wall. Consequently, the generation of wind noise caused by the traveling wind can be more effectively suppressed.

[0010] In the above aspect, preferably, the protrusion is curved in an arc shape centered on the optical axis of the lens when viewed from the outside.

[0011] According to this aspect, since the protrusions are provided over a wider area of ​​the front wall, the generation of wind noise caused by traveling wind can be suppressed more effectively.

[0012] In the above aspect, preferably, the protrusion extends linearly in the up-down direction when viewed from the outside.

[0013] According to this aspect, since the protrusions are provided over a wider area of ​​the front wall, the generation of wind noise caused by traveling wind can be suppressed more effectively.

[0014] In the above aspect, preferably, the front surface 101A of the protrusion is curved to be convex toward the rear in a plan view.

[0015] According to this aspect, since the traveling wind is more likely to flow outward along the front surface of the protrusion, even if the traveling wind generates a vortex at the front wall of the circumferential wall, the vortex is less likely to hit the rear wall of the circumferential wall. Therefore, the generation of wind noise caused by the traveling wind can be more effectively suppressed.

[0016] In the above aspect, preferably, the circumferential wall protrudes toward the outside and has a circular shape centered on the optical axis of the lens.

[0017] According to this aspect, even if a vortex is generated at the front wall of the circumferential wall by the traveling wind, the vortex is less likely to hit the rear wall of the circumferential wall.

[0018] In the above aspect, preferably, in a plan view, the front wall and the rear wall are curved toward the outside in an arc shape, and the curvature radius of the rear wall is larger than the curvature radius of the front wall.

[0019] According to this aspect, with this simple configuration, the end of the front wall on the outside can be arranged on the outside with respect to the end of the rear wall on the outside.

[0020] In the above aspect, preferably, the first plane is arranged on the outside relative to the second plane when a plane perpendicular to the optical axis of the lens and passing through the outer end of the front wall is defined as a first plane D1 and a plane perpendicular to the optical axis of the lens and passing through the outer end of the rear wall is defined as a second plane D2.

[0021] According to this aspect, the vortex generated by the traveling wind at the front wall of the circumferential wall is less likely to hit the rear wall of the circumferential wall. Therefore, the generation of wind noise caused by the traveling wind can be suppressed.

[0022] Therefore, according to the above-described aspect, it is possible to provide an attachment structure of an imaging device that can suppress the generation of wind noise caused by traveling wind. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a plan view of a vehicle in which the attachment structure of the imaging device according to the first embodiment is provided;

[0024] Figure 2 is a perspective view showing an attachment structure of an imaging device according to a first embodiment;

[0025] Figure 3 is a cross-sectional view of the attachment structure of the imaging device according to the first embodiment as viewed from the outside;

[0026] Figure 4 is a plan cross-sectional view of a main portion of the attachment structure of the imaging device according to the first embodiment;

[0027] Figure 5 is a planar cross-sectional view illustrating a relationship between an end of a front wall on the outer side and an end of a rear wall on the outer side in the attachment structure of the imaging device according to the first embodiment;

[0028] Figure 6 is a perspective view showing an attachment structure of an imaging device according to a second embodiment;

[0029] Figure 7 is a plan cross-sectional view of a main portion (when viewed from above) of an attachment structure of an imaging device according to a second embodiment;

[0030] Figure 8 is a plan cross-sectional view of a main portion (when viewed from above) of an attachment structure of an imaging device according to a third embodiment; and

[0031] Figure 9 is a plan cross-sectional view of a main portion (when viewed from above) of an attachment structure of an imaging device according to a fourth embodiment. DETAILED DESCRIPTION

[0032] (First embodiment)

[0033] Hereinafter, with reference to the drawings, a vehicle 1 provided with an attachment structure of an imaging device 12 according to a first embodiment (hereinafter referred to as “attachment structure 10 ”) will be described.

[0034] like Figure 1 As shown, vehicle 1 is, for example, a four-wheeled automobile. Vehicle 1 includes an upper structure 2 (roof) constituting the upper portion of vehicle 1. Upper structure 2 includes, for example, left and right roof side rails 3 extending in the front-to-rear direction of vehicle 1 (hereinafter referred to as the "front-to-rear direction") and arranged on the left and right sides of vehicle 1; a roof cross rail 4 extending in the lateral direction of vehicle 1 (hereinafter referred to as the "lateral direction") and extending over left and right roof side rails 3; and a roof panel 5 arranged above roof cross rail 4.

[0035] A through hole 6 is formed in the roof cross member 4 and penetrates in the vertical direction (see FIG. Figure 3 ). Annular grommet 7 (see Figure 3 ) is attached to the edge of the roof crossbar 4 defining the through hole 6.

[0036] like Figures 1 to 3 As shown, the attachment structure 10 is a structure for arranging the imaging device 12 on the upper structure 2 of the vehicle 1. In this embodiment, the attachment structure 10 is provided on the left front portion and the right front portion of the upper structure 2 of the vehicle 1. Since the left attachment structure 10 and the right attachment structure 10 have the same configuration, only one of the left attachment structure 10 and the right attachment structure 10 will be described below.

[0037] In this embodiment, the attachment structure 10 includes an imaging device 12 mounted on the upper structure 2 of the vehicle 1, a housing 13 accommodating the entire imaging device 12, and a fixing member 14 for fixing the imaging device 12 to the housing 13 (see FIG. Figure 3 In another embodiment, the housing 13 may only accommodate a portion of the imaging device 12 .

[0038] like Figure 3 and Figure 4As shown, the imaging device 12 is a device that detects conditions around the vehicle 1. The imaging device 12 is arranged above the roof crossbar 4. The imaging device 12 captures images of targets existing around the vehicle 1 (such as vehicles around the preceding vehicle, pedestrians, structures on the road, lane markings, etc.). The imaging device 12 includes, for example, a lens 15 as an optical system, an image sensor (not shown) such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS), a housing 16 that accommodates the lens 15 and the image sensor, and terminals (not shown) connected to the image sensor. The imaging device 12 captures images of the areas in front of and laterally outside the vehicle 1. That is, the lens 15 of the imaging device 12 is arranged to face the front and laterally outside of the vehicle 1. The optical axis A of the lens 15 (see Figure 4 ) is tilted forward and laterally outward in a top view. The optical axis angle θ (see Figure 5 ) is set between, for example, 30 degrees and 60 degrees. The harness 17 is connected to the above-mentioned terminal of the imaging device 12. Figure 3 As shown, the wiring harness 17 passes through a grommet 7 attached to a through hole 6 of the roof cross member 4 and is arranged below the roof cross member 4 .

[0039] Hereinafter, a direction parallel to the optical axis A of the lens 15 and extending toward the front and laterally outward of the vehicle 1 is defined as the outer direction, and the distal end of the outer direction is defined as the outer side. Similarly, a direction parallel to the optical axis A of the lens 15 and extending toward the rear and laterally inward of the vehicle 1 (i.e., the direction opposite to the outer direction) is defined as the inner direction, and the distal end of the inner direction is defined as the inner side. Furthermore, the outer direction and the inner direction are collectively referred to simply as the inner side and the outer direction.

[0040] like Figure 2 and Figure 3 As shown, the housing 13 includes a side wall 19 having a generally rectangular tubular shape and extending upward from the roof panel 5, and an upper wall 23 having a generally rectangular plate shape and arranged at the upper end of the side wall 19. The side wall 19 and the upper wall 23 define a space S inside the housing 13. The imaging device 12 is accommodated in the space S.

[0041] The side wall 19 may be integrally formed with the roof panel 5 or may be formed separately from the roof panel 5. The side wall 19 includes a front portion 25 facing substantially forward, a side portion 27 facing substantially laterally outward, and a circumferential wall 21 disposed between the front portion 25 and the side portion 27 and arranged around the lens 15.

[0042] The peripheral wall 21 has a circular shape when viewed from the outside. A through hole 28 penetrating in the inner and outer directions is formed in the peripheral wall 21. The through hole 28 is arranged around the lens 15.

[0043] like Figure 4 As shown, the circumferential wall 21 includes a front wall 29 arranged in front of the optical axis A of the lens 15 in a plan view, and a rear wall 30 arranged in the rear of the optical axis A of the lens 15 in a plan view. The front wall 29 constitutes a portion of the circumferential wall 21 disposed on the front portion 25 side, and the rear wall 30 constitutes a portion of the circumferential wall 21 disposed on the side portion 27 side. The front wall 29 and the rear wall 30 are curved toward the outside in an arc shape in a plan view.

[0044] A protrusion 31 protruding toward the outside is formed in the front wall 29. More specifically, the protrusion 31 protrudes toward the outside from the surface of the front wall 29 on the outside. It is preferable that the protrusion 31 is arranged so as not to interfere with the field of view (FoV) of the imaging device 12. Figure 2 As shown, when viewed from the outside, the protrusion 31 is curved into an arc shape centered on the optical axis A of the lens 15. The outer end of the protrusion 31 is arranged at the outermost side of the front wall 29. Hereinafter, the outer end of the protrusion 31 will be referred to as "the outer end 29A of the front wall 29."

[0045] like Figure 3 As shown, the fixing member 14 includes an upper bracket 33 fixed to the housing 13 , a lower bracket 35 arranged below the upper bracket 33 and fixed to the imaging device 12 , and a fastener 36 fastening the upper bracket 33 and the lower bracket 35 to each other.

[0046] The upper bracket 33 is formed of a metal plate and includes a main portion 37 extending along the lower surface of the upper wall 23 of the housing 13 , a leg portion 38 extending downward from an end of the main portion 37 , and a bent portion 39 bent horizontally from a lower end of the leg portion 38 .

[0047] The upper surface of the main portion 37 of the upper bracket 33 is adhered to the lower surface of the upper wall 23 of the housing 13 by, for example, an adhesive. Thus, the upper bracket 33 is fixed to the housing 13.

[0048] The bent portion 39 of the upper bracket 33 faces the upper wall 23 of the housing 13 in the up-down direction with a gap therebetween. A plurality of fastening holes 39A ( Figure 3 Only one is shown).

[0049] The lower bracket 35 is formed of a plate-like member. The lower bracket 35 includes a main portion 40 facing inward and outward, a leg portion 41 extending inward from a portion of an edge of the main portion 40, and a bent portion 42 bent horizontally from the upper end of the leg portion 41. The imaging device 12 can be fixed to the main portion 40 of the lower bracket 35 by a fastener such as a bolt.

[0050] A plurality of fastening holes 42A ( Figure 3 The center axis of each fastening hole 42A formed in the bent portion 42 of the lower bracket 35 is aligned with the center axis of the corresponding fastening hole 39A formed in the bent portion 39 of the upper bracket 33.

[0051] The fastener 36 includes a plurality of weld nuts 44 ( Figure 3 Only one of them is shown in the figure), and a plurality of bolts 45 ( Figure 3 Each bolt 45 is screwed into a corresponding weld nut 44, thereby fastening the upper bracket 33 and the lower bracket 35 to each other. Thus, the imaging device 12 is fixed to the housing 13 via the fixing member 14.

[0052] like Figure 4 and Figure 5 As shown, in the attachment structure 10, in a plan view, the outer end 29A of the front wall 29 is arranged outward relative to the outer end 30A of the rear wall 30. More specifically, a first plane D1 (see FIG. 1 ) perpendicular to the optical axis A of the lens 15 and passing through the outer end 29A of the front wall 29 is formed. Figure 5 ) relative to a second plane D2 perpendicular to the optical axis A of the lens 15 and passing through the end 30A of the rear wall 30 on the outside (see Figure 5 ) are arranged on the outside.

[0053] like Figure 5 As shown, in a Cartesian coordinate system with the front-to-back direction as the X-axis and the lateral direction as the Y-axis, the coordinates of the outer end 29A of the front wall 29 are defined as (x1, y1), and the coordinates of the outer end 30A of the rear wall 30 are defined as (x2, y2). In addition, "θ" in the figure represents the above-mentioned optical axis angle θ.

[0054] A horizontal line perpendicular to the optical axis A of the lens 15 and passing through the end 29A of the front wall 29 on the outer side (ie, a horizontal line in the first plane D1 ) is expressed by the following formula (1).

[0055] Y = tan (θ+90°)·X + b1 ... (1)

[0056] Here, "tan (θ + 90°)" represents the inclination of the line, and "b1" represents the intercept of the line on the Y axis. By replacing (X, Y) of the above formula (1) with the coordinates (x1, y1) of the end 29A of the front wall 29 on the outside, the following formula (2) is obtained.

[0057] y1 = tan (θ+90°)·x1 + b1 ... (2)

[0058] A horizontal line perpendicular to the optical axis A of the lens 15 and passing through the end 30A of the rear wall 30 on the outer side (ie, a horizontal line in the second plane D2 ) is expressed by the following formula (3).

[0059] Y = tan (θ+90°)·X + b2 ... (3)

[0060] Here, "tan (θ + 90°)" represents the inclination of the line, and "b2" represents the intercept of the line on the Y axis. By replacing (X, Y) of the above formula (3) with the coordinates (x2, y2) of the end 30A on the outer side of the rear wall 30, the following formula (4) is obtained.

[0061] y2 = tan (θ+90°)·x2 + b2 ... (4)

[0062] When the vehicle 1 moves, the traveling wind caused by the movement of the vehicle 1 may hit the circumferential wall 21 (retained at the circumferential wall 21) provided in the side wall 19 of the housing 13, thereby generating so-called wind noise. More specifically, the traveling wind becomes a vortex at the front wall 29 of the circumferential wall 21, and the vortex is retained at a portion of the rear wall 30 of the circumferential wall 21. At this time, air pressure fluctuations occur, causing the air to vibrate and generate wind noise. In order to suppress wind noise, when viewed from above, the outer end 29A of the front wall 29 needs to be arranged on the outside relative to the outer end 30A of the rear wall 30. In other words, the first plane D1 needs to be arranged on the outside relative to the second plane D2. Therefore, the following formula (5) is satisfied.

[0063] |b1| - |b2| > 0 ... (5)

[0064] According to the above formulas (2), (4) and (5), the following formula (6) is obtained.

[0065] |y1 - tan (θ+90°)·x1| - |y2 - tan (θ+90°)·x2| > 0 ... (6)

[0066] When viewed from above, if the outer end 29A of the front wall 29 is positioned inward relative to the outer end 30A of the rear wall 30 (when |b1| - |b2| ≤ 0), air that has separated from the front wall 29 (the vortex generated at the front wall 29) is likely to remain at the rear wall 30. This makes wind noise more likely to occur. However, by providing a positional difference between the front wall 29 and the rear wall 30 as in formula (6) (when viewed from above, the outer end 29A of the front wall 29 is positioned outward relative to the outer end 30A of the rear wall 30), air that has separated from the front wall 29 is less likely to remain at the rear wall 30, which contributes to reducing wind noise.

[0067] In the above attachment structure 10, even if an eddy flow is generated at the front wall 29 of the circumferential wall 21 due to traveling wind generated by the movement of the vehicle 1, the eddy flow is less likely to hit the rear wall 30 of the circumferential wall 21. Therefore, the generation of wind noise caused by the traveling wind can be suppressed.

[0068] Because the outwardly projecting protrusion 31 is formed on the front wall 29, the outward end 29A of the front wall 29 protrudes significantly outward relative to the outward end 30A of the rear wall 30. Furthermore, when viewed from the outside, the protrusion 31 is curved into an arcuate shape centered on the optical axis A of the lens 15, so the protrusion 31 is provided over a wide area of ​​the front wall 29. Therefore, even if an eddy current is generated on the front wall 29 of the circumferential wall 21 due to traveling wind, the eddy current is less likely to strike the rear wall 30 of the circumferential wall 21. Consequently, the generation of wind noise caused by traveling wind can be more effectively suppressed.

[0069] (Second embodiment)

[0070] Will refer to Figure 6 and Figure 7 The attachment structure 100 according to the second embodiment will be described. The attachment structure 100 according to the second embodiment differs from the attachment structure 10 according to the first embodiment only in the shape of the protrusion 101 provided on the front wall 29. The differences from the first embodiment will be described below. Elements that are the same as or similar to those in the first embodiment are given the same reference numerals, and repeated descriptions will be omitted.

[0071] like Figure 6 As shown in FIG. 1 , when viewed from the outside, the protrusion 101 extends linearly in the up-down direction. Figure 7 As shown, in a plan view, front surface 101A of protrusion 101 is curved to convexly face rearward. Therefore, traveling wind is more likely to flow outward along front surface 101A of protrusion 101. Even if a vortex is generated at front wall 29 of circumferential wall 21 due to traveling wind, the vortex is less likely to strike rear wall 30 of circumferential wall 21. Consequently, the generation of wind noise caused by traveling wind can be more effectively suppressed.

[0072] (Third embodiment)

[0073] Will refer to Figure 8 The attachment structure 200 according to the third embodiment will be described. The attachment structure 200 according to the third embodiment differs from the attachment structure 10 according to the first embodiment only in the shape of the circumferential wall 201. The differences from the first embodiment will be described below. Elements identical or similar to those in the first embodiment are given the same reference numerals, and repeated descriptions will be omitted.

[0074] The circumferential wall 201 protrudes outward and has a circular shape centered on the optical axis A of the lens 15. The circumferential wall 201 includes a front wall 202, which is positioned in front of the optical axis A of the lens 15 when viewed from above, and a rear wall 203, which is positioned behind the optical axis A of the lens 15 when viewed from above. The outer end 202A of the front wall 202 of the circumferential wall 201 protrudes outward relative to the front portion 25 of the housing 13. Furthermore, the outer end 203A of the rear wall 203 of the circumferential wall 201 protrudes outward relative to the side portion 27 of the housing 13. At this point, the outer end 202A of the front wall 202 is positioned outward relative to the outer end 203A of the rear wall 203. Therefore, even if a vortex is generated at the front wall 202 of the circumferential wall 201 due to traveling wind, the vortex is unlikely to strike the rear wall 203 of the circumferential wall 201.

[0075] (Fourth embodiment)

[0076] Will refer to Figure 9 The following describes an attachment structure 300 according to a fourth embodiment. The attachment structure 300 according to the fourth embodiment differs from the attachment structure 10 according to the first embodiment only in the shape of the circumferential wall 301. The differences from the first embodiment will be described below. Elements identical or similar to those in the first embodiment are given the same reference numerals, and repeated descriptions will be omitted.

[0077] The circumferential wall 301 includes a front wall 303 positioned forward of the optical axis A of the lens 15 in a plan view, and a rear wall 302 positioned rearward of the optical axis A of the lens 15 in a plan view. Both the front wall 303 and the rear wall 302 are curved outward in an arcuate shape in a plan view. The radius of curvature of the rear wall 302 of the circumferential wall 301 is greater than that of the front wall 303 of the circumferential wall 301. Therefore, with a simple configuration, the outer end 303A of the front wall 303 is positioned outward of the outer end 302A of the rear wall 302. This suppresses the generation of wind noise caused by traveling wind.

[0078] While specific embodiments of the present invention have been described above, the present invention should not be limited to the aforementioned embodiments, and various modifications and variations are possible within the scope of the present invention. In the first embodiment, a single protrusion 31 is provided on the front wall 29, but for example, a plurality of protrusions 31 may be spaced apart from one another. In the first embodiment, the protrusion 31 is rod-shaped, but the shape of the protrusion 31 is not particularly limited; for example, the protrusion 31 may be formed into a hemispherical shape.

Claims

1. An attachment structure for an imaging device, comprising: The imaging device is mounted on a roof of a vehicle; as well as a housing that houses at least a portion of the imaging device, wherein the imaging device includes a lens facing the front and lateral outside of the vehicle, The housing includes a circumferential wall arranged around the lens, The circumferential wall comprises: a front wall, the front wall being arranged in front of the optical axis of the lens when viewed from above; and a rear wall arranged behind the optical axis of the lens when viewed from above, and With the direction parallel to the optical axis of the lens and traveling toward the front and laterally outward of the vehicle defined as the outward direction and the end side in the outward direction defined as the outward, the end of the front wall on the outward is arranged on the outward relative to the end of the rear wall on the outward when viewed from above.

2. The attachment structure of the imaging device according to claim 1, wherein The front wall is provided with a protrusion protruding toward the outside.

3. The attachment structure of the imaging device according to claim 2, wherein: When viewed from the outside, the protrusion is curved in an arc shape centered on the optical axis of the lens.

4. The attachment structure of the imaging device according to claim 2, wherein The protrusion extends linearly in an up-down direction when viewed from the outside.

5. The attachment structure of the imaging device according to claim 4, wherein The front surface of the protrusion is curved to be convex toward the rear when viewed from above.

6. The attachment structure of the imaging device according to claim 1, wherein The circumferential wall protrudes toward the outside and has a circular shape centered on the optical axis of the lens.

7. The attachment structure of the imaging device according to claim 1, wherein When viewed from above, the front wall and the rear wall are curved toward the outside in an arc shape, and The curvature radius of the rear wall is greater than the curvature radius of the front wall.

8. The attachment structure of an imaging device according to any one of claims 1 to 6, wherein When a plane perpendicular to the optical axis of the lens and passing through the end of the front wall on the outer side is defined as a first plane, and a plane perpendicular to the optical axis of the lens and passing through the end of the rear wall on the outer side is defined as a second plane, the first plane is arranged on the outer side relative to the second plane.

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