JP3187516B2 - Barrier for lens protection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flash for protecting a lens used in place of a lens cap of a lens barrel of a camera.
On A.

[0002]

2. Description of the Related Art As an example of this kind of lens protection barrier , the present applicant has filed Japanese Patent Application No. Hei.
No. 1104) . This lens protection barrier will be described with reference to FIGS. In FIG. 2, a lens protection barrier 2 is provided at the tip of a lens barrel 1.
Is installed. In the exploded perspective view of the basic structure of the lens protection barrier 2 shown in FIG. 3, a drive ring 5 rotatable around the optical axis is provided between the ring-shaped front frame 3 and the rear frame 4. 1 outside the drive ring 5
A pair of operation knobs 6 are fixed at 80 ° symmetric positions.

[0003] The first is composed of three blades 7a, 7b, 7c.
In the blade group 7, each base portion of each blade is coaxially pivotally mounted on the front frame 3 by a pivot pin 8, and the tip end of each blade is a pair of blades arranged opposite to the front and back surfaces of the middle blade 7b. The pins are connected to the slots of the upper and lower blades 7a and 7c by sliding. And each blade 7a, 7b, 7
In a folded open state, the blades c are arranged substantially in a line, and in an expanded closed state, the blades are shifted from each other so as to cover more than half of the opening. An operating pin 7a 'is provided on the uppermost blade 7a in FIG. 3 to slide into the elongated hole 5a of the drive ring 5, and the blade 7a is interlocked with the rotation of the drive ring 5. In operation, the blade 7b and the blade 7c, which are connected to the pin and the slot, are sequentially linked.

A second blade group 9 is coaxially pivotally connected to the rear frame 4 by a pivot pin 10 similarly to the first blade group 7, and the tip of each blade is connected to a pin / slot. And is configured similarly to the first blade group 7.

However, in the above-described structure, two pins and slots are required to connect the respective blade groups to each other, and the driving mechanism of the blade groups requires a pin and a slot for each blade group. Therefore, there is a problem that the configuration is relatively complicated, the assembling work is complicated, and the manufacturing cost is increased.

[0006] As a barrier for protecting the lens which solves such a problem, the present applicant has filed Japanese Patent Application No. 3-182318 (Japanese Patent Application No.
(Kaihei 5-27303) .
This will be described with reference to FIGS. FIG. 4 shows a closed state of the lens protection barrier, and FIG. 5 shows an opened state thereof. The front frame 3 and the rear frame 4 are not shown. In the drawing, an intermediate ring 12 having a peripheral wall 12a having a T-shaped cross section formed on the outer peripheral surface is fixedly disposed between the front frame 3 and the rear frame 4 instead of the drive ring 5. Between the intermediate ring 12 and the rear frame 4,
A first blade group 13 composed of two blades is provided, which is pivotally mounted on a pivot pin 14 fixed to the intermediate ring 12 or the rear frame 4. The first blade 15 has a substantially crescent shape, a substantially trapezoidal first hole 15a drilled near the pivot pin 14, and a peripheral wall 12 of the intermediate ring 12 when the blade is closed.
and a stopper pin 15b that comes into contact with the stopper pin 15a. The second vane 16 is also has a generally crescent shape, but have a second hole 16a of a substantially oval shape.

A drive lever 17 pivotally mounted on a base shaft 18 fixed to the intermediate ring 12 (or the rear frame 4) has a drive pin 19 at one end thereof which slides into the first and second holes 15a and 16a. Is provided at the other end, and an operation unit 20 protruding outside the lens protection barrier 2 is provided. The driving lever 17 together with the click groove 17a is bored, it is biased in the closing direction of the right-handed direction, i.e. the blade by scan pulling S. The drive pin 19 penetrates the elongated hole 12b formed in the intermediate ring 12 and protrudes toward the front frame 3 (back side of the drawing). In addition, the interlocking relationship between the driving pin 19 and the first blade group 13 will be described.
Since the driving pin 19a is substantially trapezoidal, it is pushed in the final stage of the rotation stroke of the drive pin 19, and its operation stroke, that is, the rotation angle is relatively small. Further, the second blade 16 is provided with the second hole 1.
Since the drive pin 19a is substantially oval, it is pushed over the entire rotation stroke of the drive pin 19, and its operation stroke, that is, the rotation angle is large.

Next, the second blade group 22 is composed of two blades, and is provided between the intermediate ring 12 and the front frame 3 by a pivot pin 23 fixed to the intermediate ring 12 or the front frame 3. It is pivotally mounted and arranged symmetrically with the first blade group 13. Of the second blade group 22, the third blade 24 has a substantially crescent shape, and has a substantially trapezoidal third hole 24a and a stopper pin 24 that contacts the peripheral wall 12a of the intermediate ring 12 when the blade is closed.
b. The fourth blade 25 also has a substantially crescent shape, and has a substantially oval-shaped fourth hole 25a. The third blade 24 has the same shape as the first blade 15 and the fourth blade 25 has the same shape as that of the second blade 16 including the holes, and are arranged symmetrically. The third hole 24a and the fourth hole 25a
Also, the drive pin 19 slides. As shown in FIG. 6, a click spring 27 having projections 27a and 27b formed at both ends is attached to the intermediate ring 12 (or the rear frame 4) with fixing pins 28, respectively. Then, the protrusion 27a or 27b is fitted into the click groove 17a of the drive lever 17 between the blade closed position and the blade open position by the operation of the drive lever 17, so that a click feeling can be obtained when the operation portion 20 is opened and closed. Has become.

[0009] configuration under the above-mentioned, when is left-handed operation portion 20 of the drive lever 17 a predetermined angle in order to from the closed state of the lens protection for barrier shown in Figure 4 in an open state, the driving lever 17 It is turned leftward against the biasing force of the spring S. Then, the second hole 16a and the fourth hole 25
a, the second and fourth blades 16 pushed by the drive pin 19,
25 is opened, the first blade 15 and the third blade 24
The drive pin 19 has a substantially trapezoidal first and third hole 15a, 2
In order to move in 4a, it does not operate in the initial stage. Then, in the final region of the rotation stroke of the drive pin 19, the first and third blades 15, 24 pushed by the drive pin 19 through the first hole 15a and the third hole 24a are opened, and the first and third blades are opened.
The blade group 13 and the second blade group 22 reach the open state shown in FIG. In addition, since the one protrusion 27a of the click spring 27 fits into the click groove 17a of the drive lever 17 at the blade open position, a click feeling is obtained.

When the lens protection barrier is to be closed after the photographing is completed, when the operating portion 20 is turned clockwise, the click groove 17a and the one protrusion 27a of the click spring 27 are disengaged, and the drive lever 17 is disengaged from the spring. It is turned right by the urging force of S. Then, similarly to the above-mentioned case, first, the second and fourth blades 16 and 25 are interlocked and closed, and then the first and third blades 15 and 24 are pushed by the drive pin 19 and the first and third blades 15 and 24 are pushed. The blade group 13 and the second blade group 22 reach the closed position shown in FIG. At this time, the stopper pins 15b, 24b of the first blade 15 and the third blade 24
Abuts against the peripheral wall 12a of the intermediate ring 12, so that each blade is stopped at that position. Also, the other protrusion 27b of the click spring 27 is fitted in the click groove 17a of the drive lever 17.
Are fitted to each other to obtain a click feeling.

[0011]

However, in the above-described configuration, the drive lever 17 in the open position or the closed position causes each of the blade groups by the frictional contact between the click groove 17a and the protrusions 27a and 27b of the click spring 27. 13,2
Since the shutter 2 is held at the open / close position, the drive lever 17 is apt to move inadvertently due to vibration or the like, which has a disadvantage in that it tends to adversely affect photographing and lens protection. Further, the open / close recognition by clicking as the open / close recognition device is performed by the drive lever 17.
Is a frictional contact due to the rotation of the contact hole, there is a drawback that the contact portion formed by the click groove 17a and the protrusions 27a and 27b is rough and the like, so that the uneven touch is easily generated.

The present invention has been made in view of the above circumstances, so that the opening and closing operation of the blade group by the operating member is easy, and the first and second blade groups can be reliably held at the open and closed positions. It is an object of the present invention to provide a protective barrier for protecting a lens.

[0013]

Means for Solving the Problems] This onset Ming, first blades and the second blades are disposed so as to face between the front frame and the rear frame
Has, in the lens protection for the barrier that the first blade group and a second blade set so as to open and close operation by rotating the operation member, the contact portion is provided on said operating member, Two slopes to press the abutment
It has a roof-shaped tip surface consisting of
The boundary of the tip surface is substantially in the direction of the rotation center of the operating member.
Slidable biasing member being energized are provided, before
The operating member is configured to open the first blade group and the second blade group.
In the position corresponding to the release or closed position,
The contact portion is pushed by the inclined surface on the side corresponding to the position.
In this case, the pressure is maintained by pressing.

[0014]

In the closed state of the first and second blade groups, the operating member is pressed and held in the closing direction of the blade group by one inclined surface of the roof-shaped front end surface of the biasing member. When the is operated, the operation member operates against the urging force of the urging member, and the two blade groups are operated in the opening direction. By changing from one of the tip surfaces to the other inclined surface, the biasing member will press the operating member in the opening direction of the blade group,
The urging force pushes the blade to a predetermined open position, and the two blade groups are held at the open position.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described with reference to FIG. 1. However, the same reference numerals are used for the same members or parts as in the above-mentioned prior art, and the description is omitted. FIG. 1 is a plan view of a main part of a blade opening / closing mechanism of a lens protection barrier in a partial cross section. The first blade 15 and the third blade 24 are not provided with stopper pins 15b, 24b. The operation lever 31 pivotally supported on the intermediate ring 12 (or the rear frame 4) by the support shaft 30 has an arm 31a having a drive pin 19 having an end portion through which the drive pin 19 penetrates the long hole 12b. And contact pin 3 at the end
A driving arm 19 is provided with two arms 31b to which the second arm 2 is fixed and an operating portion 31c. ing. The operating portion 31c is provided on the peripheral wall 1 of the intermediate ring 12.
For example, a part thereof protrudes outside the intermediate ring 12 in the notch 12c of 2a. The slide lever 33 has an operating portion 31c fitted in a concave portion 33a, and fitting portions 33b, 33c having substantially U-shaped cross sections on both sides thereof.
And are slidably fitted to the notched ends b1 and b2 of the peripheral wall 12a, respectively. Therefore, the first and second blade groups 13 and 22 can be opened and closed by rotating the slide lever 33 in the direction of the peripheral wall 12a in the region of the notch portion 12c to rotate the operation lever 31. Have been.

In the vicinity of the contact pin 32 on the intermediate ring 12 (or the rear frame 4), an urging member 34 is attached to the contact pin 32.
Is slidably biased in the direction of the operation lever 31 so as to be pressed by the tip end surface. That is, the urging member 34 is provided with the locking members 35a and 35b on the intermediate ring 12 (or the rear frame 4).
35c slidably held by the contact pin 3
2 is a roof-shaped two inclined surfaces 34a, 3a.
4b, a spring 37 is interposed in the elongated hole 34c in the biasing member 34 between the pin 36 fixed to the surface of the intermediate ring 12 and the distal end surface 34d of the elongated hole 34c in a compressed state. ing. Therefore, when the contact pin 32 is pressed against the first inclined surface 34a of the biasing member 34, the operation lever 31 is pressed in the left-handed direction to hold the first and second blade groups 13, 22 in the closed state. And the slide lever 33 is locked in a state where one fitting portion 33c is in contact with the notch end b2 (see FIG. 1). Contact pin 3
2 is pressed against the second inclined surface 34b of the biasing member 34, the operation lever 31 is pressed in the clockwise direction to rotate the first and
The slide lever 33 is locked at a position where the second blade group 13, 22 is held in an open state, and the slide lever 33 is in a state where the other fitting portion 33b is in contact with the notch end b1.

[0017] Further, on the surface of the intermediate ring 12 side of the operation lever 31 is attached reflective mirror 38, the intermediate phosphorous
The operating lever 12 is located on the surface of the
A photo-interrupter 41 composed of a light-emitting element 39 and a light-receiving element 40 is mounted at a position facing the reflection mirror 38 when the light-emitting element is turned. Therefore, the output of the photointerrupter 41 is OFF at the closed position of the blade group shown in FIG. 1 and is ON at the open position.

Since the present embodiment is constructed as described above, the contact pin 32 of the operating lever 31 is pressed by the urging member 34 when the first and second blade groups 13 and 22 shown in FIG. Is held in a state of being pressed by the first inclined surface 34a of the front end surface of the first member. From this state, the slide lever 33
When the control lever 31 is turned clockwise, the operation lever 31 is turned clockwise about the support shaft 30, so that the rotation of the drive pin 19 first pushes the second and fourth blades 16 and 25 . At this time, the contact lever 32 of the distal end of the two arms 31b pushes the urging member 3 against the urging force of the spring 37 of the urging member 34.
4 while pushing up the first inclined surface 34a, and over the boundary between the inclined surfaces 34a and 34b, which are the tops of the tips, the biasing force of the spring 37 is now applied to the operation lever 31.
It works in the right-handed direction.
The operating force on the id lever 33 becomes very light . Then, the drive pin 19 also pushes the first and third blades 15 and 24 in the final region of the rotation stroke, and the first and second blade groups 13 and 22 are opened. At this position, the slide lever 33 is locked at a predetermined position by one of the fitting portions 33b abutting against the notch end b1 of the peripheral wall 12a, and the blade groups and the operation lever 31 are not excessively rotated. . Further, in the open position of the blades, the operation lever 31 is rotated Sasera
As a result, the reflection mirror 38 is positioned above the photo-interrupter 41, so that light from the light-emitting element 39 is reflected by the reflection mirror 38 and received by the light-receiving element 40. Is turned on, it is possible to recognize the blade open state via a display (not shown).

When operating the blade from the open state to the closed position, if the slide lever 33 is rotated left, the operation lever 31 is interlocked and rotated left, and the drive pin 19 rotates each blade in the closing direction. . At the same time, the contact pin 32 is rotated while pushing the second inclined surface 34 b of the urging member 34 against the urging force of the spring 37. The biasing force of the spring 37
Acts in the direction of left rotation with respect to the operation lever 31.
Now look, is stopped at a predetermined position where the other of the fitting portion 33c abuts the cutout end b2 of the slide lever 33. At this position, each blade group reaches a closed state as shown in FIG.
This state is maintained by the urging force of the spring 37 . This blade closed position, the reflecting mirror 38 for deviating from the photo-interrupter 41, the output of the photo interrupter 41 can recognize through the display OFF, the vanes closed. As described above, the operating lever 31 is in contact with the contact pin in both the blade open position and the closed position.
32 is pressed against the inclined surfaces 34a and 34b of the urging member 34.
In the state, it held becomes Tei Rukoto.

As described above, in this embodiment, the operation lever 3
1 is reliably pressed and held by the urging member 34 at the predetermined blade open position and the closed blade position, and does not inadvertently move due to vibration or the like, so that opening and closing control can be performed accurately. Moreover, the biasing force of one spring 37 is
Affects both opening and closing operations and their operation
In the direction of operation of the operation lever 31 from the middle of
Since going on to, or during the operation of the slide lever 33
Can feel the resistance, and can open and close the blade with one light touch. Also, the opening / closing state of the lens protection barrier
For the recognition, performed in a non-contact by the reflection mirror 38 and photo-interrupter 41, it is possible to uniformly and easily recognized.

In the opening / closing recognition device, it goes without saying that the mounting positions (members) of the reflection mirror 38 and the photo interrupter 41 may be reversed.
In addition, the reflection mirror 38 may be attached to a portion outside the aperture of any one of the blades. In that case, the position of the photo interrupter 41 is adjusted accordingly. In addition, the opening / closing recognition device is not limited to the reflection mirror 38 and the photo interrupter 41 shown in the above-described embodiment, but may be any other appropriate device such as a magnetic recognition device including a permanent magnet and a Hall element. A device may be provided.

The operating lever 31, the biasing member 34, the open / close recognition device, and the like need not always be disposed between the rear frame 4 and the intermediate ring 12, but are disposed between the front frame 3 and the intermediate ring 12. You may make it. The operation lever 31 and the slide lever 33 constitute an operation member.
And the permanent magnet, etc., serve as the first detection unit and the photo interrupter 4
1, 1 and a Hall element etc. comprise a 2nd detection part.

[0023]

As described above, the barrier for the lens barrel according to the present invention is provided with the biasing member for biasing and holding the operating member between the open position and the closed position of the first and second blade groups. As a result, the first and second blade groups are not inadvertently opened and closed due to vibration or the like, and each of the blade groups can be reliably held at a predetermined open / close position. it can.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part of a barrier for protecting a lens according to an embodiment of the present invention, showing a blade closed state.

FIG. 2 is a perspective view of a prior art lens protection barrier.

FIG. 3 is an exploded perspective view of a main part of the lens protection barrier according to FIG. 2;

FIG. 4 is a main part plan view showing a closed state of a lens protection barrier according to another prior art.

FIG. 5 is a plan view of a main part showing an opened state of the lens protection barrier of FIG. 4;

6 is a front view of a main part of the opening / closing recognition device based on a click feeling of the lens protection barrier shown in FIG . 4 ;

[Description of Signs] 3 front frame 4 rear frame 13 first blade group 19
... Drive pin, 22 second blade group 31, operating lever 32, contact pin 33, slide lever 3,
4 ... biasing member, 37 ... spring, 38 ... reflective mirror, 41 ... photo interrupter.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03B 11/04 G03B 9/00-9/34

Claims (1)

(57) [Claims] 1. A first blade group and a second blade group between a front frame and a rear frame.
Be arranged in blades are opposed in the lens protection for barriers so as to opening and closing the first blade group and the second blade set by rotation of <br/> to the operating member, The operating member has a contact portion, and the contact portion
Roof-shaped tip surface consisting of two inclined surfaces for pressing
And the boundary of the tip surface is controlled by the elastic member.
Is provided with slidable biasing member is biased in a substantially center of rotation of the work member, said operating member, said first
Corresponds to the open or closed position of the blade group and the second blade group
Position, the side corresponding to those positions
A lens protecting burr characterized in that the contact portion is pressed and held by a slope.
A.