Imaging device

Abstract

This reduces the decrease in airtightness in structures that use O-rings between the lens barrel and the housing. [Solution] The imaging device 10 has a lens unit 11, a housing 12, and a sealing part 13. The lens unit 11 has a lens barrel 14 and a base 15. The housing 12 has a covering part 17 and a peripheral wall 18. The sealing part 13 is sandwiched between the base 15 and the covering part 14. The outer diameter of the sealing part 13 removed from the lens unit 11 and housing 12 is smaller than the inner diameter of the peripheral wall 18. The inner diameter of the sealing part 13 is larger than the outer diameter of the lens barrel 14.

Description

Technical Field

[0001] The present disclosure relates to an imaging apparatus.

Background Art

[0002] In imaging apparatuses, a configuration in which a lens barrel that supports an optical system is incorporated into a housing is known. In such a configuration, it is known to provide a sealing material such as an O-ring between the housing and the lens barrel in order to seal the inside of the housing (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of Invention

Problem to be Solved by the Invention

[0004] However, the sealing performance inside the housing may be degraded even when an O-ring is used.

[0005] An object of the present disclosure is to mitigate the degradation of sealing performance in a structure using an O-ring provided between a lens barrel and a housing.

Means for Solving the Problem

[0006] An imaging apparatus according to a first aspect is: a lens unit including a lens barrel that holds an optical system, and a pedestal portion that extends outward from a central axis along a circumferential direction from a side surface of the lens barrel; a housing portion including a covering portion that has a hole through which the lens barrel is inserted and covers the pedestal portion so as to face the pedestal portion, and a peripheral wall portion that stands along a periphery of the hole toward the pedestal portion side from a surface of the covering portion on the pedestal portion side; and an annular sealing portion sandwiched between the pedestal portion and the covering portion. The outer diameter of the sealing portion removed from the lens unit and housing is smaller than the inner diameter of the peripheral wall, and the inner diameter of the sealing portion is larger than the outer diameter of the lens barrel. [Effects of the Invention]

[0007] According to this disclosure, the reduction in airtightness is mitigated in a structure using an O-ring provided between the lens barrel and the housing. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-sectional view of the imaging device according to this embodiment, along the optical axis. [Figure 2] Figure 1 is a schematic exploded cross-sectional view illustrating the size of each element constituting the imaging device. [Figure 3] Figure 1 is an exploded perspective view of the imaging device. [Figure 4] This is a schematic exploded cross-sectional view of a modified image sensor shown in Figure 1. [Figure 5] This is a cross-sectional view showing another modified example of the imaging device in Figure 1, with the compression of the sealing portion by the lens unit and housing released. [Figure 6] This is a cross-sectional view showing the state of an imaging device in the process of being manufactured, using a sealing portion that does not have the features of the present invention. [Figure 7] Figure 6 is a cross-sectional view of the imaging device. [Figure 8] This is a cross-sectional view of an imaging device using a different sealing portion that does not have the features of the present invention. [Figure 9] This is a cross-sectional view showing a condition that may occur in an imaging device having a peripheral wall portion that does not possess some of the features of the present invention. [Figure 10] Figure 1 is a cross-sectional view illustrating the positional relationship of the sealing portion and other components in the imaging device when the sealing portion is located on one side within the peripheral wall. [Modes for carrying out the invention]

[0009] Embodiments of this disclosure will be described below with reference to the drawings. In the components shown in the following drawings, the same components are denoted by the same reference numerals.

[0010] As shown in Figure 1, the imaging device 10 is composed of a lens unit 11, a housing 12, and a sealing part 13. The imaging device 10 may further include an image sensor and a circuit board in order to perform imaging functions.

[0011] The lens unit 11 has a lens barrel 14 and a base portion 15. The lens barrel 14 holds an optical system 16. The optical system 16 may include at least one refractive element such as a lens. The base portion 15 extends outward from the central axis of the lens barrel 14 along the circumferential direction of the central axis of the lens barrel from the side surface of the lens barrel 14. As shown in Figure 2, the base portion 15 may have a first surface s1 on the lens barrel 14 side that presses against a sealing portion 13, which will be described later. The first surface s1 may be a plane perpendicular to the axial direction of the lens barrel 14.

[0012] The housing portion 12 has a covering portion 17 and a peripheral wall portion 18. As shown in Figure 3, the covering portion 17 has a hole hl through which the lens barrel 14 is inserted. As shown in Figure 1, the covering portion 17 covers the base portion 15 so as to face the base portion 15.

[0013] As shown in Figure 2, the peripheral wall portion 18 is erected from the second surface s2 of the covering portion 17 on the base portion 15 side toward the base portion 15. The peripheral wall portion 18 runs along the periphery of the hole hl. As shown in Figure 3, the lens unit 11 may be fixed to the housing portion 12 using fasteners 19 or the like. The height ht of the inner peripheral wall of the peripheral wall portion 18 from the covering portion 17, specifically the second surface s2, may be lower than the axial thickness tk of the sealing portion 13. This height ht may be more than half of the axial thickness tk of the sealing portion 13.

[0014] As shown in Figure 2, the bottom surface of the peripheral wall portion 18 on the second surface s2 side may be inclined toward the axis side of the hole h1. Alternatively, as shown in Figure 4, the bottom surface may be a plane parallel to the first surface s1. In the configuration where the bottom surface is a plane parallel to the first surface s1, when viewed from the optical axis direction of the optical system in the imaging apparatus 10, the inner end of the peripheral wall portion 18 may be located on the optical axis side of the pedestal portion 15 over the entire circumference.

[0015] The housing portion 12 may be a part of the housing of the entire imaging apparatus 10. The housing portion 12 may be a part on the object side obtained by dividing the housing in the direction along the optical axis.

[0016] As shown in Figure 5, at least one of the pedestal portion 15 and the covering portion 17 may be provided with a truncated conical side surface-shaped inclined surface ss. The inclined surface ss may be located on the center side of the optical axis in the imaging apparatus 10. Further, the inclined surface ss may extend along the circumferential direction of the optical axis. Further, the inclined surface ss may be inclined outward with respect to the optical axis. The inclined surface ss may be provided on the mutually facing surface sides of the pedestal portion 15 and the covering portion 17.

[0017] The inclined surface ss may bring the sealing portion 13 into contact with the pedestal portion 15 and the covering portion 17 over the entire circumference in a state where the sealing portion 13, which will be described later, is not compressed by the pedestal portion 15 and the covering portion 17. In other words, the inclined surface ss provided on the sealing portion 13 may have a size that does not contact the inner peripheral surface over the entire circumference of the sealing portion 13 in a state where the housing portion 12 is removed from the lens unit 11 and the sealing portion 13 is placed on the pedestal portion 15. Further, the inclined surface ss provided on the covering portion 17 may have a size that does not contact the inner peripheral surface over the entire circumference of the sealing portion 13 in a state where the housing portion 12 is removed from the lens unit 11 and the sealing portion 13 is placed on the covering portion 17.

[0018] The sealing portion 13 is sandwiched between the pedestal portion 15 and the covering portion 17. As shown in Figure 3, the sealing portion 13 is annular. The sealing portion 13 is, for example, an O-ring formed of an elastic member such as rubber.

[0019] The sealing portion 13, when detached from the lens unit 11 and housing portion 12, may have the following dimensions. As shown in Figure 2, the outer diameter od1 of the sealing portion 13 is smaller than the inner diameter id2 of the peripheral wall portion 18. Also, the inner diameter id1 of the sealing portion 13 is larger than the outer diameter od3 of the lens barrel 14, and preferably larger than the inner diameter idhl of the hole hl. Furthermore, the sum of the inner diameter id1 and outer diameter od1 of the sealing portion 13 may be larger than the sum of the inner diameter id2 of the peripheral wall portion 18 and the inner diameter idhl of the hole hl.

[0020] The imaging device 10 of this embodiment, having the configuration described above, comprises a lens unit 11 having a lens barrel 14 that holds the optical system and a base portion 15 extending outward from the central axis along the circumferential direction from the side of the lens barrel 14; a housing portion 12 having a hole hl through which the lens barrel 14 is inserted and a covering portion 17 that covers the base portion 15 so as to face the base portion 15, and a peripheral wall portion 18 that is erected along the periphery of the hole hl toward the base portion 15 from a first surface s1 of the covering portion 17 toward the base portion 15; and an annular sealing portion 13 sandwiched between the base portion 15 and the covering portion 17. The outer diameter od1 of the sealing portion 13 removed from the lens unit 11 and housing portion 12 is smaller than the inner diameter id2 of the peripheral wall portion 18, and the inner diameter id1 of the sealing portion 13 is larger than the outer diameter od3 of the lens barrel 14. In the manufacturing process of the imaging device 10, the lens unit 11 is mounted on the housing portion 12 with the sealing portion 13 housed within the peripheral wall portion 18. However, in a configuration where the outer diameter of the sealing portion 13' is larger than the inner diameter of the peripheral wall portion 18, as shown in Figure 6, the sealing portion 13' that has been press-fitted into the peripheral wall portion 18 may detach from the peripheral wall portion 18 before mounting. As shown in Figure 7, when the lens unit 11 is mounted with the sealing portion 13' detached from the peripheral wall portion 18, a portion of the sealing portion 13' may flow out from the space defined between the first surface s1 and the second surface s2. In this state, the sealing portion 13' may wrinkle in a part of the circumferential direction and the amount of deformation of the sealing portion 13' may decrease, thus reducing its sealing performance. Furthermore, in a configuration where the inner diameter of the sealing portion 13" is larger than the outer diameter of the lens barrel 14, as shown in Figure 8, a portion of the sealing portion 13" may flow out from the space defined between the first surface s1 and the second surface s2. In this state, the sealing portion 13" may wrinkle in a part of the circumferential direction and the amount of deformation of the sealing portion 13' may decrease, thus reducing the sealing performance. In response to such phenomena, the imaging device 10 having the above configuration does not require the sealing portion 13 to be pressed into the circumferential wall portion 18, and the sealing portion 13 is not necessarily located between the lens barrel 14 and the covering portion 17 when viewed from the optical axis direction, thus reducing the possibility of the sealing portion 13 flowing out from the space defined between the first surface s1 and the second surface s2. Therefore, the imaging device 10 can mitigate the decrease in sealing performance between the lens unit 11 and the housing portion 12.

[0021] Furthermore, in the imaging device 10, the height ht of the inner circumferential wall of the peripheral wall portion 18 from the covering portion 17 is lower than the axial thickness tk of the sealing portion 13. As shown in Figure 9, in a configuration where the height ht of the inner circumferential wall of the peripheral wall portion 18 from the covering portion 17 is higher than the axial thickness tk of the sealing portion 13, a portion of the sealing portion 13 in the circumferential direction may be sandwiched between surfaces of the base portion 15 other than the first surface s1 and surfaces of the peripheral wall portion 18 other than the second surface s2. As a result, the airtightness provided by the sealing portion 13 may decrease in that portion. In response to this issue, the imaging device 10 having the above configuration can mainly sandwich the sealing portion 13 between the first surface s1 and the second surface s2 around its entire circumference, even if the sealing portion 13 is compressed by surfaces other than the first surface s1 and the second surface s2. Therefore, the imaging device 10 can mitigate the decrease in airtightness.

[0022] Furthermore, in the imaging device 10, the inner end of the peripheral wall portion 18, when viewed from the optical axis direction of the optical system, is positioned on the optical axis side of the base portion 15 along its entire circumference. With this configuration, the imaging device 10 can sandwich the sealing portion 13 around its entire circumference with a plane perpendicular to the optical axis. Therefore, the imaging device 10 can further reduce the decrease in the airtightness of the sealing portion 13.

[0023] Furthermore, in the imaging device 10, the sum of the inner diameter id1 and outer diameter od1 of the sealing portion 13 is greater than the sum of the inner diameter id2 of the peripheral wall portion 18 and the inner diameter idhl of the hole hl. With this configuration, as shown in Figure 10, even if the imaging device 10 shifts a portion of the sealing portion 13 to one side so that it abuts against the peripheral wall portion 18, the other portion is not positioned inside the hole hl. Therefore, the imaging device 10 reduces the possibility of the sealing portion 13 being pinched between the lens barrel 14 and the inner peripheral wall of the hole hl. Thus, the imaging device 10 can further reduce the decrease in the airtightness of the sealing portion 13.

[0024] Furthermore, in the imaging device 10, at least one of the base portion 15 and the covering portion 17 is provided with a frustoconical inclined surface ss that slopes outward along the circumferential direction on the axis side. With this configuration, the imaging device 10 functions so that the inclined surface ss displaces the sealing portion 13 outward in the axial direction around its entire circumference. Therefore, the imaging device 10 reduces the possibility of the sealing portion 13 being pinched between the lens barrel 14 and the inner circumferential wall of the hole hl. As a result, the imaging device 10 can further reduce the decrease in the airtightness of the sealing portion 13.

[0025] In one embodiment, (1) the imaging device is A lens unit having a lens barrel that holds the optical system, and a base portion that extends outward from the central axis along the circumferential direction from the side of the lens barrel, A housing portion having a hole through which the lens barrel is inserted and covering the base portion so as to face the base portion, and a peripheral wall portion erected along the periphery of the hole toward the base portion from the surface of the covering portion toward the base portion, It comprises an annular sealing portion sandwiched between the base portion and the covering portion, The outer diameter of the sealing portion removed from the lens unit and housing is smaller than the inner diameter of the peripheral wall, and the inner diameter of the sealing portion is larger than the outer diameter of the lens barrel.

[0026] (2) In the imaging device described in (1) above, The height of the inner circumferential wall of the circumferential wall portion from the covering portion is lower than the thickness of the sealing portion in the axial direction.

[0027] (3) In the imaging device described in (2) above, Viewed from the optical axis direction of the optical system, the inner end of the peripheral wall portion is located on the optical axis side of the base portion over its entire circumference.

[0028] (4) In any of the imaging devices described in (1) to (3) above, The sum of the inner and outer diameters of the sealing portion is greater than the sum of the inner diameter of the peripheral wall portion and the inner diameter of the hole.

[0029] (5) In any of the imaging devices described in (1) to (4) above, At least one of the base portion and the covering portion is provided with a frustoconical side-shaped inclined surface that slopes outward along the circumferential direction, on the side of the axis center.

[0030] The diagrams illustrating the embodiments described herein are schematic. Dimensions and proportions shown in the drawings do not necessarily correspond to actual dimensions.

[0031] While embodiments relating to this disclosure have been described based on the drawings and examples, it should be noted that those skilled in the art can make various modifications or alterations based on this disclosure. Therefore, it should be noted that these modifications or alterations are within the scope of this disclosure. For example, the functions included in each component can be rearranged in a logically consistent manner, and multiple components can be combined into one or separated.

[0032] All of the constituent elements described in this disclosure, and / or all of the disclosed methods or steps of processing, may be combined in any combination except for any combination in which these features are mutually exclusive. Furthermore, each of the features described in this disclosure may be replaced by an alternative feature that works for the same, equivalent, or similar purpose, unless expressly disregarded. Thus, unless expressly disregarded, each of the disclosed features is merely an example of a comprehensive set of identical or equivalent features.

[0033] Furthermore, the embodiments relating to this disclosure are not limited to any specific configuration of the embodiments described above. The embodiments relating to this disclosure can be extended to all novel features or combinations thereof described herein, or all novel methods or processing steps or combinations thereof described herein.

[0034] In this disclosure, the designations "First," "Second," etc., are identifiers used to distinguish the configurations. Configurations distinguished by the designations "First," "Second," etc., in this disclosure may have their numbers swapped. For example, the first face may swap the identifiers "First" and "Second" with the second face. The swapping of identifiers occurs simultaneously. The configurations remain distinguishable even after the swapping of identifiers. Identifiers may be deleted. Configurations from which identifiers have been deleted are distinguished by codes. The designations "First," "Second," etc., in this disclosure should not be used alone to interpret the order of the configurations or to justify the existence of smaller numbered identifiers. [Explanation of Symbols]

[0035] 10 Imaging device 11 Lens Unit 12. Enclosure 13, 13', 13” sealing section 14 Telescope Tubes 15. Base 16 Optical system 17 Covering part 18 Peripheral wall section 19 Fasteners hl hole ss slope s1 First face s2 Second side

Claims

1. A lens unit having a lens barrel that holds the optical system, and a base portion that extends outward from the central axis along the circumferential direction from the side of the lens barrel, A housing portion having a hole through which the lens barrel is inserted and covering the base portion so as to face the base portion, and a peripheral wall portion erected along the periphery of the hole from the surface of the covering portion facing the base portion toward the base portion, It comprises an annular sealing portion sandwiched between the base portion and the covering portion, The outer diameter of the sealing portion removed from the lens unit and housing is smaller than the inner diameter of the peripheral wall, and the inner diameter of the sealing portion is larger than the outer diameter of the lens barrel. Imaging device.

2. In the imaging apparatus according to claim 1, The height of the inner circumferential wall of the circumferential wall portion from the covering portion is lower than the thickness of the sealing portion in the axial direction. Imaging device.

3. In the imaging device according to claim 2, Viewed from the optical axis direction of the optical system, the inner end of the peripheral wall portion is located on the optical axis side of the base portion over its entire circumference. Imaging device.

4. In the imaging device according to any one of claims 1 to 3, The sum of the inner and outer diameters of the sealing portion is greater than the sum of the inner diameter of the peripheral wall portion and the inner diameter of the hole. Imaging device.

5. In the imaging apparatus according to claim 1, At least one of the base portion and the covering portion is provided with a frustoconical side surface that slopes outward along the circumferential direction, on the side of the axis center. Imaging device.

Images