Lens barrel

Abstract

To provide a lens barrel that has improved drip-proof performance.SOLUTION: A lens barrel 101 according to the present invention comprises: a first cylinder part 435 that has an internal space 498 and an opening 499 communicating with the internal space 498; a second cylinder part 417 that advances into the internal space 498 from the opening 499; and a first elastic member 301 that is arranged on the peripheral part of the opening 499 of the first cylinder part 435 so that an uncut surface 306 becomes non-parallel to the advance direction of the second cylinder part 417.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a lens barrel. [Background technology]

[0002] It has been known that moisture can seep in through gaps between cylindrical sections that move relative to each other in a lens barrel, causing short circuits or other problems in electronic components, which can lead to malfunctions. Patent Document 1 discloses a lens barrel whose drip-proof performance is improved by providing a plush to prevent moisture from entering through gaps provided between the barrel portions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-114858 A Summary of the Invention [Problem to be solved by the invention]

[0004] In order to further improve the drip-proof performance of the lens barrel as disclosed in Patent Document 1, it is conceivable to apply a water repellent agent to the plush. In this case, however, in order to simplify the production process, the plush used is generally obtained by applying a water repellent agent to the sheet surface of a plush sheet attached to a backing paper, and then cutting the plush sheet along the side.

[0005] Furthermore, in the lens barrel disclosed in Patent Document 1, the plush is positioned so that the cut surface, which is the side surface to which relatively little water repellent agent is applied compared to the non-cut surface, which is the sheet surface, faces the direction of water penetration, making it difficult to fully obtain the drip-proofing effect that comes from applying a water repellent agent. SUMMARY OF THE PRESENT EMBODIMENTS An object of the present invention is to provide a lens barrel with improved water-proof performance. [Means for solving the problem]

[0006] The lens barrel according to the present invention is a lens barrel that houses a lens, and includes a first tube portion, a second tube portion that is disposed inside the first tube portion and moves along an optical axis of the lens relative to the first tube portion, and an elastic member that is disposed between an inner diameter surface of the first tube portion and an outer diameter surface of the second tube portion so as to be parallel to the optical axis of the lens, the elastic member being made of a nonwoven fabric coated with a water repellent agent, On the object side At the end, at least a portion is arranged to extend in a direction different from the optical axis of the lens, one end of the side of the elastic member faces the image surface between the first and second tube portions, and the other end of the side of the elastic member is bent so as to extend in a direction different from the optical axis of the lens. Effect of the Invention

[0007] According to the present invention, it is possible to provide a lens barrel with improved drip-proof performance. [Brief description of the drawings]

[0008] [Figure 1] 1A and 1B are cross-sectional views of a lens barrel according to a first embodiment at a wide-angle end and a telephoto end. [Diagram 2] FIG. 3 is a development view of a cam ring included in the lens barrel according to the first embodiment, as viewed from the outer periphery side. [Diagram 3] FIG. 2 is a perspective view of an elastic member included in the lens barrel according to the first embodiment. [Figure 4] 1A and 1B are a partially enlarged cross-sectional view and a partially enlarged perspective view of a lens barrel according to a first embodiment. [Diagram 5] 11A and 11B are a partially enlarged cross-sectional view and a partially enlarged perspective view of a lens barrel according to a second embodiment. [Figure 6] FIG. 1 is a block diagram of a camera system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The lens barrel according to the present embodiment will be described in detail below with reference to the accompanying drawings. Note that the drawings may be drawn at a scale different from the actual scale in order to facilitate understanding of the present embodiment. In the following description, the direction perpendicular to the optical axis of each lens group may be referred to as the radial direction, and the direction around the optical axis of each lens group may be referred to as the circumferential direction.

[0010] It has been known that moisture can seep in through gaps between parts that move relative to one another in a lens barrel, causing short circuits or other problems in electronic components, which can result in malfunctions. Furthermore, in a lens barrel such as an interchangeable lens having a long focal length and a high zoom ratio, some parts move significantly forward and backward in the optical axis direction.

[0011] Generally, the greater the distance moved in the optical axis direction, the greater the surface area of ​​the portion of the exterior part to which moisture has adhered that is drawn into the interior of the lens barrel. In addition, the internal volume of the lens barrel changes significantly when it is moved forward or backward, making it easier for moisture to be absorbed from the outside into the interior. Therefore, the greater the distance that a lens barrel has parts that move back and forth, the more difficult it is to ensure drip-proofing.

[0012] In order to prevent such infiltration of moisture, it is known to provide a water-absorbent material such as plush. However, although the water-absorbing member can prevent the intrusion of a certain amount of water by absorbing the water, once a certain amount is exceeded, the water-absorbing member becomes saturated and the drip-proof performance cannot be satisfied. In particular, in a lens barrel that has a large extension amount, i.e., a large distance that it moves back and forth in the optical axis direction, the required amount of water that can be absorbed is also large, making it necessary to increase the volume of the water absorbing member, for example.

[0013] On the other hand, it is also possible to improve the drip-proof performance by applying a water-repellent supplementary material to the water-absorbing member. However, when applying a water repellent agent to a water-absorbent material such as plush, taking mass production into consideration, typically the water repellent agent is applied to a plush sheet attached to a backing sheet, the sheet is dried, and then cut and divided into multiple plush pieces.

[0014] In this case, the sides of the multiple pieces of plush that are perpendicular to the surface of the backing paper are in contact with each other, making it difficult to apply the water repellent agent, and the sides of the plush have weaker water repellency than the sheet surface (uncut surface) to which the water repellent agent is applied. Furthermore, if the plush is attached to the lens barrel so that the side with relatively weak water repellency faces the direction of moisture penetration, the side with weak water repellency will be exposed to the path of water penetration, making the plush more likely to become saturated and weakening its drip-proofing effect.

[0015] Another possible configuration is to ensure drip-proof performance by abutting a packing made of a rubber material such as silicone rubber against the lens barrel that moves relatively. This type of configuration can generally ensure high watertightness, but because rubber has a high coefficient of friction, the sliding load generated when the lens barrel is slid increases due to the frictional force generated by the rubber member. This may result in, for example, an increase in the operating torque during zoom operation, or a sliding noise occurring between the rubber member and the lens barrel, which may degrade the quality of the lens when the lens barrel is operated to zoom.

[0016] In this embodiment, the above-mentioned problems are solved by adopting the configuration described below, making it possible to provide a lens barrel with further improved drip-proof performance.

[0017] [First embodiment] FIG. 6 shows a block diagram of a camera system 350 including a lens barrel 101 and a camera 201 according to the first embodiment.

[0018] As shown in FIG. 6, the lens barrel 101 according to this embodiment includes a first group barrel 401, an aperture unit 405, a focus barrel 404, a rear group barrel 410, an image blur correction unit 411, and a fifth group barrel 412. Furthermore, the lens barrel 101 according to this embodiment is equipped with a gyro sensor 106 as a blur detection means, and a main CPU 102 for controlling the drive of the entire lens barrel 101 and for performing calculations. The lens barrel 101 according to this embodiment also includes an image blur correction unit drive source 108 , an aperture unit drive source 109 , and a focus barrel drive source 110 .

[0019] In the lens barrel 101 according to this embodiment, the main CPU 102 issues instructions (sends commands) to the aperture unit drive source 109 and the focus barrel drive source 110, respectively, to drive the aperture unit 405 and the focus barrel 404.

[0020] Furthermore, when performing image blur correction control, the main CPU 102 refers to the detection value of the gyro sensor 106 , calculates the amount of blur correction, and transmits an instruction to the image blur correction unit drive source 108 . Then, the image blur correction unit 411 is driven in the Y direction (yaw direction) and the P direction (pitch direction) that are orthogonal to the optical axis X, thereby performing blur correction. Thereby, the image blur correction unit 411 and the image blur correction unit drive source 108 function as an image blur correction unit.

[0021] The main CPU 102 also functions as a determination unit that determines the holding state of the lens barrel 101 or the camera 201 from the detection value of the gyro sensor 106 .

[0022] The camera 201 (imaging device) includes an image sensor 202 that photoelectrically converts a subject image formed via the lens barrel 101. The imaging element 202 is typically a CCD image sensor or a CMOS image sensor.

[0023] The lens barrel 101 in this embodiment is fixed to the camera 201 via a mount 414, and an image of the subject is formed on an image sensor 202 held by the camera 201 via optical components inside the lens barrel 101, thereby capturing an image of the subject.

[0024] As shown in FIG. 6, the camera 201 is also provided with a main CPU 203, a release button 204 as an operating member, a main power source 205, an image recording medium 206, and the like. Here, the release button 204 has a two-stage depression configuration, with the first and second stages being referred to as SW1 and SW2, respectively. SW1 issues instructions for preparations for starting shooting, such as returning from a shooting standby state, starting image stabilization, starting autofocus, and starting photometry. In SW2, an instruction is given to record the image obtained by shooting onto the image recording medium 206.

[0025] In addition, in order to supply power to the lens barrel 101 and exchange shooting information, communication is performed between the main CPU 203 of the camera 201 and the main CPU 102 of the lens barrel 101 via a contact block (not shown) provided on the mount 414.

[0026] Next, the structure of lens barrel 101 according to this embodiment will be described in detail. 1(a) and (b) show cross-sectional views of a lens barrel 101 according to this embodiment at the wide-angle end and the telephoto end, respectively. In the following description, the side where a subject to be photographed is located is defined as the object side, and the side where the image sensor 202 of the camera 201 is located is defined as the image surface side. In addition, in Figs. 1(a) and (b), the object side and the image surface side are shown as the left and right sides, respectively.

[0027] As shown in FIGS. 1( a ) and 1 ( b ), the lens barrel 101 according to this embodiment includes a first lens group 451 , a second lens group 452 , a third lens group 453 , a fourth lens group 454 , and a fifth lens group 455 . Furthermore, the lens barrel 101 according to this embodiment includes a cam ring 416 , a linear barrel 417 , a manual focus ring (MF) unit 419 , a front fixed barrel 423 , an outer ring 427 , and a driving IC 431 . Furthermore, the lens barrel 101 according to this embodiment is equipped with a zoom ring 435 , a protective frame 461 , a rear fixed barrel 472 , a guide barrel 474 , and an AF motor 480 .

[0028] The first lens 451 is held by a first lens barrel 401 , and the first lens barrel 401 is fixed to a linear cylinder 417 . The second lens group 452 has a function of correcting image blur by moving in a direction perpendicular to the optical axis, and is held by an image blur correction unit 411 . The image blur correction unit 411 is fixed to the guide tube 474 and does not move in the optical axis direction during zooming.

[0029] The third lens group 453 is held by the rear lens barrel 410 , and the fourth lens group 454 is held by the focus lens barrel 404 . Furthermore, the focus barrel 404 is held by a rear group barrel 410 via a guide mechanism provided therein.

[0030] Furthermore, the focus barrel 404 is moved in the optical axis direction relative to the rear group barrel 410 by a drive mechanism to perform focus adjustment. Furthermore, the fifth group lens 455 is held by a fifth group lens barrel 412 .

[0031] The aperture unit 405 has a function of adjusting the amount of light, and is fixed to the rear group barrel 410 . Also, the guide tube 474 is fixed to the rear fixed tube 472 with, for example, screws, and is provided with a plurality of linear grooves.

[0032] The cam ring 416 is a cam member rotatably fitted to the inner periphery of the guide cylinder 474, and a plurality of cam grooves are provided in the circumferential direction of the cam ring 416. The zoom ring 435 is rotatably held by a guide cylinder 474, and is provided with a number of cam grooves.

[0033] The linear barrel 417 is engaged with a cam groove formed in the zoom ring 435 and a linear groove formed in the guide barrel 474 via a cam follower. With this, when the zoom ring 435 is manually rotated to perform zooming, the cam follower provided on the linear motion cylinder 417 slides, causing the linear motion cylinder 417 to move in the optical axis direction.

[0034] The driving IC 431 is a printed circuit board on which a microcomputer and the like are arranged, and is fixed to the rear fixed barrel 472 . The outer ring 427 is fixed to the rear fixed barrel 472 together with the mount 414, for example, with screws, and the front fixed barrel 423 is fixed to the rear fixed barrel 472, for example, with screws.

[0035] The MF unit 419 is supported so as to be rotatable around a front fixed cylinder 423 as an axis. By rotating the MF unit 419, the rotation is detected by a sensor (not shown), and manual focus adjustment is performed according to the amount of rotation. The AF motor 480 is fixed to the rear group lens barrel 410 and drives the focus lens barrel 404 .

[0036] FIG. 2 shows a development view of cam ring 416 of lens barrel 101 according to this embodiment, viewed from the outer periphery side.

[0037] As shown in FIG. 2, cam ring 416 is formed with a cam groove 416a for linear barrel 417, a cam groove 416b for rear group barrel 410, a cam groove 416c for fifth group barrel 412, and a cam groove 416d for protective frame 461.

[0038] As described above, when the zoom ring 435 is manually rotated, the linear cylinder 417 moves in the optical axis direction. Furthermore, since the cam followers provided on the linear barrel 417 are engaged with the cam grooves 416a formed in the cam ring 416, when the linear barrel 417 moves in the optical axis direction, the cam ring 416 rotates around the optical axis.

[0039] Further, the rear group barrel 410 is engaged with a cam groove 416b formed in the cam ring 416 and a rectilinear groove formed in the guide barrel 474 via a cam follower. Furthermore, the fifth group barrel 412 is engaged with a cam groove 416c formed in the cam ring 416 and a rectilinear groove formed in the guide barrel 474 via a cam follower. Thereby, when the cam ring 416 is rotated, the cam followers provided on the rear group barrel 410 and the fifth group barrel 412 slide, and the rear group barrel 410 and the fifth group barrel 412 each move in the optical axis direction.

[0040] The protective frame 461 is provided on the image surface side of the fifth group barrel 412, and the two cam followers and the stopper member are attached to the protective frame 461 with, for example, screws. The stopper member has a linear groove engagement portion, and by engaging with the linear groove of the guide cylinder 474, it is held so as to be movable in the optical axis direction and unable to rotate around the optical axis.

[0041] Both cam followers engage with the linear grooves of the guide tube 474, similar to the linear groove engagement portions of the stopper members, thereby allowing the protective frame 461 to move in the optical axis direction but not rotate around the optical axis. The stopper member is provided with a cam groove engaging portion that engages with a cam groove 416d formed in the cam ring 416. Additionally, both cam followers engage with cam grooves 416d formed in cam ring 416, similar to the cam groove engaging portions of the stopper member. As a result, when the cam ring 416 is rotated, the protective frame 461 moves in the optical axis direction along the cam groove 416d.

[0042] In this manner, zooming can be performed by rotating the zoom ring 435, which moves the linear barrel 417, the rear group barrel 410, and the fifth group barrel 412 in the optical axis direction. Additionally, the protective frame 461 also moves in the optical axis direction at the same time as the zooming. Here, when zooming is performed from the wide-angle end to the telephoto end, the fifth group barrel 412 and the protective frame 461 are configured to move forward toward the object side.

[0043] Next, the configuration of the drip-proof structure provided in lens barrel 101 according to this embodiment will be described.

[0044] As described above, when the zoom ring 435 is rotated, the linear cylinder 417 moves forward and backward in the optical axis direction. At this time, as zooming is performed toward the telephoto end, the cylindrical portion of the rectilinear cylinder 417 is exposed to the outer diameter side of the lens barrel 101, whereas when zooming is performed toward the wide-angle end, the cylindrical portion of the rectilinear cylinder 417 is stored inside the lens barrel 101.

[0045] That is, when the zoom ring 435 is operated toward the wide-angle end in an environment in which water droplets adhere to the lens barrel 101, the rectilinear cylinder 417 advances inside the lens barrel 101, specifically into the internal space 498 of the zoom ring 435. This may cause water droplets to enter the inside of the lens barrel 101. This is not only due to the cylindrical surface of rectilinear cylinder 417 with water droplets being drawn into the interior of lens barrel 101, but also due to the fact that the internal volume of lens barrel 101 increases with zooming operation, causing air to flow in through various gaps in lens barrel 101.

[0046] Therefore, in the lens barrel 101 according to this embodiment, in order to prevent the infiltration of moisture from the gap between the linear cylinder 417 and the zoom ring 435, an elastic member 301 is provided as described below.

[0047] 3(a) and (b) each show a perspective view of an elastic member 301 provided in the lens barrel 101 according to this embodiment.

[0048] As shown in FIGS. 3(a) and (b), elastic member 301 is a flat member made of, for example, nonwoven fabric, and in lens barrel 101 according to this embodiment, Toray Industries, Inc.'s Ecsaine (registered trademark) is used. One surface of the elastic member 301 is an adhesive surface 302 made of double-sided tape, and the other surface is a water repellent coating surface 306 .

[0049] As shown in FIG. 3(b), a plurality of elastic members 301 are formed by first cutting a flat sheet attached to a mount 300 via an adhesive surface 302. In this state, a water repellent is applied to the uncut surface opposite to adhesive surface 302, that is, the exposed surface, to form water repellent applied surface 306. Due to the action of the water repellent applied to water repellent application surface 306 in this manner, elastic member 301 made of nonwoven fabric becomes more likely to repel water, and waterproof performance can be improved.

[0050] On the other hand, the surface perpendicular to the adhesive surface 302 and the water-repellent application surface 306, i.e., the cut surface 303 which is the side surface of the elastic member 301, is in contact with the multiple elastic members 301 and therefore does not have the water-repellent applied thereto, and therefore the water-repellent effect is weakened and the surface is more likely to absorb moisture.

[0051] In lens barrel 101 according to the present embodiment, elastic member 301 to which the water repellent agent has been applied in this manner is arranged in lens barrel 101 as described below, taking the above into consideration.

[0052] 4(a), (b), and (d) are partial enlarged cross-sectional views of the zoom ring 435 (a first cylindrical portion) and the linear barrel 417 (a second cylindrical portion) in the lens barrel 101 of this embodiment, respectively. FIG. 4(c) is a partially enlarged perspective view of the lens barrel 101 according to this embodiment.

[0053] As shown in FIG. 4( d ), in the lens barrel 101 according to this embodiment, the rectilinear barrel 417 moves from an opening 499 in the zoom ring 435 to an internal space 498 of the zoom ring 435 along the central axis of the zoom ring 435 . An elastic member 301 is attached (mounted) to an inner diameter surface (inner surface) 435a of the zoom ring 435. In addition, since the elastic member 301 is attached so as to abut against the abutment portion 435b of the zoom ring 435, the influence of misalignment of the attachment can be suppressed.

[0054] In the lens barrel 101 of this embodiment, as shown in FIG. 4(b), by bending the object side end 301a of the elastic member 301 toward the main body portion 301b, the elastic member 301 is also attached to the attachment surface 435c (end surface) of the zoom ring 435. In this manner, the elastic member 301 is bent and attached in an L-shape along the inner diameter surface 435 a of the zoom ring 435 and the attachment surface 435 c , that is, along the shape of the zoom ring 435 .

[0055] Here, if the end portion 301a and the main body portion 301b of the elastic member 301 are referred to as the first and second elastic members, respectively, then the first elastic member 301a and the second elastic member 301b in the elastic member 301 can be considered to be integrally formed with each other. In this case, the end 301 a of the elastic member 301 can be considered to be disposed on the periphery of the opening 499 of the zoom ring 435 .

[0056] In addition, in the lens barrel 101 according to this embodiment, the effect can be obtained if the angle α that the water-repellent coating surface 306 at the end 301a of the elastic member 301 makes with respect to the traveling direction (advance / retreat direction) of the linear motion cylinder 417 is not 0°. That is, the effect can be obtained if the water repellent coating surface 306 at the end 301a of the elastic member 301 and the moving direction of the rectilinearly moving cylinder 417 are not parallel to each other.

[0057] Moreover, it is preferable that the angle α that the water repellent agent coated surface 306 at the end 301a of the elastic member 301 forms with the moving direction of the rectilinearly moving cylinder 417 is 45° or more. Furthermore, it is most preferable that the angle α that the water repellent coating surface 306 at the end 301a of the elastic member 301 makes with respect to the traveling direction of the straight-advance tube 417 is 90°, i.e., the water repellent coating surface 306 at the end 301a and the traveling direction of the straight-advance tube 417 are perpendicular to each other.

[0058] On the other hand, in the lens barrel 101 according to this embodiment, the water repellent coating surface 306 of the main body 301b of the elastic member 301 is attached (mounted) to the inner diameter surface 435a of the zoom ring 435 so as to be approximately parallel to the direction of travel of the linear cylinder 417.

[0059] Then, as shown in FIG. 4(c), the elastic member 301 is attached along the circumferential direction of the zoom ring 435 so that the circumferential ends 304, which are each in the form of a notch, are adjacent to each other. In other words, in lens barrel 101 according to this embodiment, elastic member 301 has both circumferential ends with portions each cut away so that they have complementary shapes.

[0060] Also, as shown in Figures 3(a) and 4(c), at least one, and in this embodiment, three linear notches 305 (cutout portions) are formed in the elastic member 301 at equal intervals, i.e., at positions that divide the elastic member 301 into four equal parts. This makes it possible to suppress tension that occurs when the elastic member 301 is bent into an L shape along the inner diameter surface 435a and the attachment surface 435c of the zoom ring 435, thereby improving reliability against peeling off and the like. However, the present invention is not limited to this, and the cutout 305 may be formed as a cutout portion in which a part of the elastic member 301 is removed.

[0061] Furthermore, in order to ensure the drip-proof performance of the elastic member 301, the gap between the adjacent circumferential ends 304 when the elastic member 301 is attached as described above is important. In other words, taking into consideration variations in the components of the lens barrel 101 of this embodiment and variations during assembly, a certain degree of gap between adjacent circumferential ends 304 is necessary, but if the gap is too wide, moisture will penetrate through the gap. On the other hand, in the optical axis direction, by attaching the elastic member 301 so as to abut against the abutment portion 435b, the deviation due to the attachment becomes relatively small.

[0062] Therefore, in the lens barrel 101 of this embodiment, the circumferential ends 304 of the elastic member 301 are formed into a notch shape, so that the gap between adjacent circumferential ends 304 after attachment, i.e., the circumferential length of the elastic member 301, can be adjusted. By narrowing the gap in the optical axis direction while appropriately ensuring the gap between the adjacent circumferential ends 304, it is possible to achieve both improvements in ease of assembly and drip-proof performance.

[0063] In the lens barrel 101 according to this embodiment, as shown in FIG. 4(d), a front cover 307 (cover member) is attached so as to sandwich the elastic member 301 attached to the zoom ring 435. Specifically, as shown in FIG. 4(d), the zoom ring 435 is provided with a fixed mountain portion 435d, which is a convex shape that protrudes in the outer diameter direction, around the entire circumference.

[0064] On the other hand, the front cover 307 is provided with three fixing claws 307a protruding inwardly at 120° intervals in the circumferential direction. Then, as the fixed mountain portion 435d overcomes and engages with the fixed claw portion 307a, a mutually attracting force is generated between the front cover 307 and the zoom ring 435, and the elastic member 301 is sandwiched and fixed between the zoom ring 435 and the front cover 307.

[0065] Then, as shown in FIG. 4( d ), when zooming is performed from the telephoto end to the wide-angle end, the linear barrel 417 moves into the internal space of the zoom ring 435 so that the cylindrical portion of the linear barrel 417 is stored inside the lens barrel 101. At this time, if water droplets are attached to the outer peripheral surface of the straight-advance tube 417, the water will tend to infiltrate in the direction of movement of the straight-advance tube 417 as the straight-advance tube 417 moves.

[0066] At this time, moisture on the outer peripheral surface of the linear barrel 417 that has entered the opening 499 of the zoom ring 435 is repelled when it reaches the water-repellent coated surface 306 of the elastic member 301, thereby preventing moisture from entering the interior of the lens barrel 101. In addition, since the moisture that has penetrated onto the outer peripheral surface of the straight-moving tube 417 does not come into direct contact with any surfaces of the elastic member 301 other than the water-repellent coated surface 306, water absorption by the elastic member 301 can also be suppressed, thereby improving the drip-proof performance.

[0067] As described above, in the lens barrel 101 of this embodiment, the end 301a of the elastic member 301 is positioned on the periphery of the opening 499 of the zoom ring 435 so that the water-repellent coating surface 306 at the end 301a is non-parallel to the direction of travel of the linear cylinder 417. As a result, moisture that has entered the opening 499 of the zoom ring 435 when the linear barrel 417 advances into the internal space 498 of the zoom ring 435 is repelled when it reaches the water repellent applied surface 306 of the elastic member 301 .

[0068] In this way, in the lens barrel 101 according to this embodiment, the intrusion of moisture into the interior can be suppressed, and the drip-proof performance can be further improved. Furthermore, by preventing the size of the drip-proof member from increasing in comparison with the conventional configuration, deterioration of quality when operating the lens barrel can be prevented.

[0069] It should be noted that the zoom ring 435 and the linear barrel 417 do not need to be integral parts, and may be composed of a plurality of parts.

[0070] [Second embodiment] 5(a) and (b) respectively show a partially enlarged cross-sectional view and a partially enlarged perspective view of a lens barrel 103 according to the second embodiment. In addition, since the lens barrel 103 of this embodiment has the same configuration as the lens barrel 101 of the first embodiment except for the configuration of the elastic member, the same components are given the same numbers and their descriptions are omitted.

[0071] In the lens barrel 103 of this embodiment, as shown in Figures 5(a) and (b), the first elastic member 311, which is a circular sheet member, and the second elastic member 320, prevent the intrusion of moisture that accompanies the movement of the linear barrel 417 due to zoom operation. Specifically, one uncut surface of the first elastic member 311 serves as an adhesive surface 312, and the other uncut surface serves as a water repellent application surface 316. Then, the adhesive surface 312 of the first elastic member 311 is attached to the attachment surface 435c of the zoom ring 435, and the first elastic member 311 is sandwiched between the front cover 307 and the zoom ring 435, thereby fixing the first elastic member 311.

[0072] Moreover, one uncut surface of the second elastic member 320 serves as an adhesive surface 312, and the adhesive surface 312 is attached to the inner diameter surface (inner surface) 435a of the zoom ring 435 so as to abut against the abutment portion 435b. As shown in FIG. 5(b), the second elastic member 320 is arranged by being attached along the circumferential direction of the zoom ring 435 so that the notched circumferential ends 304 are adjacent to each other.

[0073] Then, as shown in FIG. 5( a ), when zooming is performed from the telephoto end to the wide-angle end, the linear barrel 417 moves into the internal space of the zoom ring 435 so that the cylindrical portion of the linear barrel 417 is stored inside the lens barrel 101. At this time, if water droplets are attached to the outer peripheral surface of the straight-advance tube 417, the water will tend to infiltrate in the direction of movement of the straight-advance tube 417 as the straight-advance tube 417 moves.

[0074] At this time, moisture on the outer peripheral surface of the linear barrel 417 that has entered the opening of the zoom ring 435 is repelled when it reaches the water-repellent coated surface 316 of the first elastic member 311, thereby preventing moisture from entering the interior of the lens barrel 101. In addition, since the moisture that has penetrated onto the outer peripheral surface of the straight-line tube 417 does not come into direct contact with any surfaces of the first elastic member 311 other than the water-repellent coated surface 316, water absorption by the first elastic member 311 can also be suppressed, thereby improving the drip-proof performance. In addition, in the lens barrel 103 of this embodiment, even if a large amount of moisture penetrates and the first elastic member 311 becomes saturated with water, the second elastic member 320 absorbs the moisture, thereby preventing the moisture from penetrating into the inside of the lens barrel 101.

[0075] As described above, in the lens barrel 103 of this embodiment, the first elastic member 311 is positioned on the peripheral portion of the opening 499 of the zoom ring 435 so that the water-repellent coating surface 316 of the first elastic member 311 is non-parallel to the direction of travel of the linear cylinder 417. As a result, moisture that enters the opening 499 of the zoom ring 435 when the linear barrel 417 advances into the internal space 498 of the zoom ring 435 is repelled when it reaches the water repellent applied surface 306 of the first elastic member 311 . In this way, the lens barrel 103 according to this embodiment can prevent moisture from entering the interior, further improving the drip-proof performance.

[0076] Although the preferred embodiments have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist thereof. [Explanation of symbols]

[0077] 101 Lens barrel 301 Elastic members 306 Uncut surface 417 Straight tube (second tube section) 435 Zoom ring (first barrel part) 498 Interior Space 499 Opening

Claims

1. A lens barrel that houses a lens, A first cylindrical portion; a second tube portion disposed inside the first tube portion and movable along an optical axis of the lens relative to the first tube portion; an elastic member disposed between an inner diameter surface of the first cylindrical portion and an outer diameter surface of the second cylindrical portion so as to be parallel to an optical axis of the lens; The elastic member is made of a nonwoven fabric coated with a water repellent agent, the elastic member is disposed at an end portion of the first tube portion on the object side so as to extend in a direction different from an optical axis of the lens, a lens barrel, characterized in that one end of a side surface of the elastic member faces an image surface between the first tube portion and the second tube portion, and the other end of the side surface of the elastic member is bent so as to extend in a direction different from the optical axis of the lens.

2. The lens barrel according to claim 1 , wherein the elastic member is attached to the inner diameter surface of the first cylindrical portion, and the water repellent is applied to a surface opposite to the surface to which the elastic member is attached.

3. 3. The lens barrel according to claim 1, wherein at least a portion of the elastic member is disposed on a plane perpendicular to an optical axis of the lens at the end of the first cylindrical portion.

4. 4. The lens barrel according to claim 1, wherein the elastic member comprises a first elastic member and a second elastic member.

5. 5. The lens barrel according to claim 1, wherein the first tube portion and the second tube portion are cylindrical.

6. 6. The lens barrel according to claim 1, wherein the elastic member is provided with at least one notch.

7. 7. The lens barrel according to claim 6, wherein the elastic member has a plurality of the notches formed at equal intervals.

8. 8. The lens barrel according to claim 1, wherein the elastic member has both circumferential ends, each of which has a portion cut away so that the ends have complementary shapes.

9. 9. The lens barrel according to claim 1, further comprising a cover member that holds the other end of the elastic member between the first cylinder portion and the cover member.

10. The lens barrel according to any one of claims 1 to 9, and an imaging device having an imaging element that photoelectrically converts a subject image formed through the lens barrel.

Images