JP2005017376A - Lens barrel for interchangeable lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens barrel for an interchangeable lens capable of stably securing permeability. <P>SOLUTION: The lens barrel is provided with: a lens barrel main body with a waterproof function (1st frame member 100 and 2nd frame member 200); a frame member (rear cover member 260 etc.) attached to the lens barrel main body; an opening part 261b arranged in a part of the frame member (circumferential wall of rear cover member 260 etc.) so as to ventilate between the inside and outside of the lens barrel main body; and a water-repellant sheet 262 attached so as to cover the opening part 261b (from inside or outside) so as to allow the air to pass through the opening part 261b and so as to repel water drops. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an interchangeable lens barrel mounted on a camera, and more particularly to an interchangeable lens barrel having a waterproof function-equipped ventilation means.
[0002]
[Prior art]
In general, in a waterproof camera equipped with a zoom lens, when the zoom lens barrel is moved back and forth in the optical axis direction for zooming, the internal pressure of the camera changes accordingly. As a result, the zooming load fluctuates and places a heavy burden on the zoom motor and the like.
[0003]
As a means for solving such a problem, there is known one in which a plurality of air holes are formed in the back cover of the camera body, and a sheet-like member having water repellency and air permeability is bonded and fixed to the inner surface side of these air holes. (See Patent Document 1).
[0004]
[Patent Document 1]
JP 05-173240 A (paragraph [0015], FIG. 9)
[0005]
[Problems to be solved by the invention]
If the means shown in Patent Document 1 is used, it is possible to prevent intrusion of water droplets and to absorb changes in the internal pressure of the camera accompanying zooming. For this reason, the burden on the zoom motor or the like is remarkably reduced. However, in what is shown in Patent Document 1, if the outer surfaces of a plurality of vent holes opened in the back cover of the camera body are covered with some object, the air permeability is immediately lost. Further, when dust or the like adheres to the sheet-like member after long-term use, clogging occurs. However, since the sheet-like member is bonded and fixed to the back cover of the camera, there is a problem that the recovery procedure is very troublesome.
[0006]
The present invention has been made based on such circumstances, and an object of the present invention is to provide an interchangeable lens barrel capable of stably ensuring air permeability.
[0007]
[Means for Solving the Problems]
In order to solve the above problems and achieve the object, the interchangeable lens barrel of the present invention has the following characteristic configuration. Note that features other than those described below will be clarified in the embodiments.
[0008]
The interchangeable lens barrel of the present invention includes a lens barrel body having a waterproof function, a frame member attached to the lens barrel body, a part of the frame member, and an interior of the lens barrel body. An opening that allows ventilation between the outside and a water repellent sheet that is mounted so as to cover the opening, allows air to enter and exit through the opening, and repels water droplets. It is characterized by.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of an interchangeable lens barrel according to the first embodiment of the present invention, and is a cross-sectional view showing an upper half portion cut along an optical axis. FIG. 2 is an exploded perspective view showing a partial configuration of the interchangeable lens barrel according to the embodiment. FIG. 3 is an exploded perspective view showing another partial configuration of the interchangeable lens barrel according to the embodiment. 2 is connected to N in FIG.
[0010]
1 to 3, reference numeral 100 denotes a substantially cylindrical first frame member having an optical axis OA in the axial center portion. In the hollow portion of the first frame member 100, a first group lens 110, a second group lens 120, a third group lens 130, and a fourth group lens 140 are housed. The first group lens 110 is moved by the rotation of the cam ring 150, and the position is controlled. Further, the second group lens 120, the third group lens 130, and the fourth group lens 140 move along the first guide rod 161 and the second guide rod 162 (not shown) by the rotation of the cam ring 150, and relative position control is performed. Is made.
[0011]
Reference numeral 170 denotes a filter ring, 171 denotes a first group lens frame, 172 denotes a second group lens frame, 173 denotes a third group lens frame, and 174 denotes a fourth group lens frame. Reference numeral 180 denotes an aperture blade, 181 denotes an aperture drive frame, and 182 denotes an aperture movement frame.
[0012]
1 to 3, reference numeral 200 denotes a second frame member (fixed frame) fitted on the outer periphery of the first frame member 100. The first frame member 100 and the second frame member 200 are relatively movable in the optical axis direction. The first frame member 100 is moved in the optical axis direction by the rotation of the zoom ring 250 mounted on the second frame member 200, so that a so-called zooming operation is performed. Between the outer peripheral surface of the first frame member 100 and the inner peripheral surface of the second frame member 200, for example, a waterproof member 310 having an annular shape made of rubber is interposed.
[0013]
A front cover member 210 is attached to the front end portion (left end portion in FIG. 1) of the second frame member 200. On the outer peripheral surface of the second frame member 200, a distance ring 220, a distance display ring 230, a zoom base ring 240, a zoom ring 250, a rear cover member 260, and the like are sequentially fitted from the right in FIG. The rear cover member 260 is provided with ventilation means (261, 262, 263) with a waterproof function. A lens mount member 270 is screwed to the rear end portion of the second frame member 200 so as to be positioned at the outer central portion of the rear cover member 260.
[0014]
A first seal member 301 formed of an O-ring is interposed at a three-part joint portion of the front end portion of the second frame member 200, the front cover member 210, and the distance ring 220. A second seal member 302 made of an O-ring is interposed between the distance ring 220 and the distance display ring 230. A third seal member 303 made of an O-ring is interposed between the distance display ring 230 and the ring portion 241 of the zoom stage ring 240. A fourth seal member 304 made of an O-ring is interposed between the ring portion 241 of the zoom stage ring 240 and the zoom ring 250. A fifth seal member 305 made of an O-ring is interposed between the zoom ring 250 and the rear cover member 260. Further, between the rear cover member 260 and the lens mount member 270, for example, a waterproof ring 320 having an annular shape made of rubber is interposed.
[0015]
Reference numeral 221 denotes a distance pulse generating ring. Reference numeral 231 is a distance contact piece, 232 is a scale ring, and 233 is a distance display window made of a transparent member. Reference numeral 251 denotes a zoom contact piece, 252 denotes a contact piece cover, and 253 denotes a zoom rubber ring. Further, reference numeral 261 denotes an opening for ventilation, 262 denotes a water repellent sheet, and 263 denotes a protective cover, and these constitute the ventilation means with waterproof function. Reference numeral 280 denotes a thickness dimension adjusting spacer generally referred to as “Kanza”. Reference numeral 290 denotes a cover rear frame, and 291 denotes a dustproof member.
[0016]
Next, the waterproof means-equipped ventilation means will be described in detail. 4 (a) and 4 (b) are diagrams showing the configuration of the ventilation means with waterproof function, and show the configuration of the rear cover member 260 attached to the rear end portion of the second frame member 200 and its peripheral portion. Yes. (A) is a front view, (b) is a 4b-4b arrow directional cross-sectional view of (a).
[0017]
As shown in FIGS. 4 (a) and 4 (b), ventilation means 260A and 260B with waterproof function are provided at symmetrical positions different from each other by 180 ° on the peripheral wall of the rear cover member 260, respectively.
[0018]
These waterproof ventilation means 260A and 260B have the same configuration. Therefore, the structure will be described below by taking the waterproof function-equipped ventilation means 260A as an example. A plurality of openings 261 are formed in the circumferential wall of the rear cover member 260 along the circumferential direction at predetermined intervals. Of these openings 261, openings 261a provided at three locations near the central portion and both ends are openings for attaching the protective cover, and a plurality of openings 261b other than the above are openings of the lens barrel body. An opening that allows ventilation between the inside and the outside. A water repellent sheet 262 is attached so as to cover the inside or outside (outside in this embodiment) of the ventilation opening 261b. Each of these water-repellent sheets 262 is formed of porous tetrafluoroethylene resin or the like and has a water-impervious property that allows air to enter and exit between the front and back surfaces and prevents the passage of water droplets. is doing.
[0019]
A protective cover 263 is attached on the water repellent sheet 261. The protective cover 263 is entirely rectangular and curved in an arc shape. A plurality of protrusions are formed on the inner surface of the protective cover 263 along the longitudinal direction at predetermined intervals. Of these protrusions, the protrusions 263a provided at three positions near the central portion and both ends are mounting bosses, and the plurality of protrusions 263b other than the above are ribs for forming air passages. The mounting boss 263a can be removably inserted into the mounting opening 261a.
[0020]
Thus, the protective cover 263 is detachably attached to the rear cover member 260. Then, the air flows between the ribs 263b as an air passage. For this reason, even if the portion of the ventilation means 260A with a waterproof function is covered with a finger or other object, there is no possibility that the air permeability is impaired. The protective cover 263 also functions as a pressing member for the water repellent sheet 262. For this reason, there is no special need for adhesion and fixing of the water repellent sheet 262 or screwing.
[0021]
(Feature points in the embodiment)
[1] The interchangeable lens barrel shown in the embodiment is
A lens barrel body (first frame member 100, second frame member 200) having a waterproof function;
A frame member (such as a rear cover member 260) attached to the lens barrel body (100, 200);
An opening 261b provided on a part of the frame member (a peripheral wall of the rear cover member 260 and the like) and allowing ventilation between the inside and the outside of the lens barrel body (100, 200);
A water repellent sheet 262 that is mounted so as to cover (from the inside or outside) the opening 261b, allows air to enter and exit through the opening 261b, and repels water droplets;
It is provided with.
[0022]
Since the interchangeable lens barrel can be ventilated through the opening 261b, a change in the internal pressure of the camera accompanying zooming of the zoom lens can be absorbed, and the burden on the zoom motor and the like can be reduced. In addition, the water repellent action of the water repellent sheet 262 can prevent water droplets and the like from entering through the opening 261b. In particular, the ventilation opening 261b is provided to a frame member such as the rear cover member 260 of the interchangeable lens barrel body (100, 200), and the water-repellent sheet 262 for drip-proofing is provided in the opening. It is only mounted so as to cover the portion 261b, and adhesion and fixing are not particularly performed. For this reason, the possibility that the opening 261b is blocked by a finger or other object is extremely low. Further, when the water-repellent sheet 262 for drip-proof is clogged, it can be dealt with relatively easily by removing the interchangeable lens barrel and replacing the water-repellent sheet 262.
[0023]
[2] The interchangeable lens barrel shown in the embodiment is the interchangeable lens barrel according to [1],
A protective cover 263 having an air passage on the inner surface and covering the opening 261b or the water repellent sheet 262 is further provided.
[0024]
In the interchangeable lens barrel, the opening 261b or the water-repellent sheet 262 is protected by a protective cover 263 having an air passage formed with a rib or the like (or a hole) on the inner surface. For this reason, even if the opening 261b is covered with fingers or other objects, there is no possibility that the air permeability is impaired. Further, damage to the water repellent sheet 262 can be prevented. Further, it can be used as a pressing member for the water repellent sheet 262. For this reason, not only the water-repellent sheet 262 is not required to be adhered and fixed, but also screws are not required.
[0025]
[3] The interchangeable lens barrel shown in the embodiment is the interchangeable lens barrel according to [2],
The protective cover may be detachably attached to the frame member 200.
[0026]
In the interchangeable lens barrel, the water repellent sheet 262 can be easily replaced or cleaned as needed by removing the protective cover 263 as necessary.
[0027]
[4] The interchangeable lens barrel shown in the embodiment is the interchangeable lens barrel according to [1], [2], or [3],
The frame member (260) is a rear cover member 260 attached to a rear end portion of the lens barrel body (100, 200).
[0028]
In the above interchangeable lens barrel, when the interchangeable lens barrel is used while being mounted on a camera, the probability that a user's finger or the like holding the camera will block the opening 261b is extremely low.
[0029]
(Modification)
The interchangeable lens barrel shown in the embodiment includes the following modifications.
[0030]
-A ventilating unit with a waterproof function is provided only in one place.
[0031]
A sheet in which the water repellent sheet 262 is attached to the inside of the opening 261b or both inside and outside.
[0032]
-As a water-repellent sheet, instead of a sheet (thin plate) made of porous tetrafluoroethylene resin, a cloth-treated member is used. In this case, the lens barrel functions as a drip-proof specification. Therefore, it can be provided to the user at a lower cost.
[0033]
・ Applied to a camera with a vent in the back cover of the camera body. In this case, in addition to the vent hole on the camera body side, a further vent hole is added on the lens barrel side. Therefore, the movement of the lens in the lens barrel becomes lighter, and the load on the zoom driving motor and the like is greatly reduced.
[0034]
【The invention's effect】
According to the present invention, the possibility that the ventilation opening is blocked by a finger or other object is extremely low, and the water-repellent sheet can be easily replaced. Therefore, it is possible to provide an interchangeable lens barrel that can ensure air permeability stably.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a schematic configuration of an interchangeable lens barrel according to a first embodiment of the present invention.
FIG. 2 is an exploded perspective view showing a partial configuration of the interchangeable lens barrel according to the first embodiment of the present invention.
FIG. 3 is an exploded perspective view showing the configuration of another part of the interchangeable lens barrel according to the first embodiment of the present invention.
4A and 4B are views showing the structure of a waterproof function ventilation means according to the first embodiment of the present invention, in which FIG. 4A is a view of a rear cover member as viewed from the front side, and FIG. FIG. 4B is a cross-sectional view taken along line 4b.
[Explanation of symbols]
OA optical axis 100 first frame members 110 to 140 first group lens to fourth group lens 200 second frame member 210 front cover member 220 distance ring 230 distance display ring 240 zoom base ring 250 zoom ring 260 rear cover member 270 lens mount Member 280 Thickness adjustment spacer (Kanza)
290 Rear cover frames 301 to 305 First to fifth seal members 310 Waterproof member 320 Waterproof ring

Claims (4)

A lens barrel body having a waterproof function;
A frame member attached to the lens barrel body;
An opening that is provided in a part of the frame member and allows ventilation between the inside and the outside of the lens barrel body;
A water repellent sheet that is mounted so as to cover the opening, allows air to enter and exit through the opening, and repels water droplets;
An interchangeable lens barrel characterized by comprising: The interchangeable lens barrel according to claim 1, further comprising a protective cover having an air passage on an inner surface and covering the opening or the water-repellent sheet. The interchangeable lens barrel according to claim 2, wherein the protective cover is detachably attached to the frame member. The interchangeable lens barrel according to claim 1, wherein the frame member is a rear cover member attached to a rear end portion of the lens barrel main body.

Images