JP2562965Y2 - Barrier for lens barrel - Google Patents

Description

[Detailed description of the invention]

[0001]

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

[0002]

2. Description of the Related Art Conventionally, in a video camera, a still camera, or the like, a lens cap is attached to a lens barrel to protect a front lens of the lens barrel. However, this must be removed at the time of shooting. It was very inconvenient and sometimes lost. In order to eliminate such inconvenience, for example, in a still camera, a barrier for a lens barrel having two blades has already been used. However, the two-piece blade has a disadvantage that it goes against the demand for a compact camera because the barrier becomes large, and the two-piece blade has a cantilever structure, so it is easily bent and has poor durability. There were also disadvantages.

On the other hand, there has been proposed a barrier for a lens barrel in which a pair of blades composed of a plurality of blades having a substantially crescent shape is provided, and these blades are opened and closed by folding and expanding the blades.

[0004]

However, in such a lens barrel barrier, each blade group is disposed at a position approximately 180 ° away from the optical axis inside the lens barrel barrier. A drive pin is provided in the vicinity of the rotation support shaft of the blade group, and the interlocking mechanism is configured to engage with the drive ring, so that a link mechanism is required or the space occupied by the interlocking mechanism inside the barrier is large. In other words, there is a problem that the same disadvantages as the two-barrel lens barrel barrier occur, in which the size of the barrier is limited as a whole.

The present invention has been made in view of the above problems, and has as its object to provide a barrier for a lens barrel having an interlocking mechanism that is smaller and occupies a smaller space. It is another object of the present invention to provide a lens barrel barrier that facilitates connection between a conduction terminal of an open / close recognition switch and a camera body side terminal when the lens barrel barrier is mounted on the camera body.

[0006]

A barrier for a lens barrel according to the present invention has a driving member rotatably disposed around an optical axis between a first frame and a second frame. At least one blade of each of the first blade group and the second blade group arranged symmetrically with respect to the driving member is linked to the driving member. In the barrier for a lens barrel configured to open and close the second blade group, the first blade group is formed by a first protrusion provided near the base of the blade and a first engagement portion formed on the driving member. ,
Further, the second blade group is characterized in that it is interlocked with the driving member by a second projection provided at the blade tip and a second engagement portion formed on the driving member. .

The barrier for a lens barrel according to the present invention is:
The present invention is characterized in that two conductive terminals of an open / close recognition switch connected to a connection terminal on the camera body side are arranged concentrically on a mounting surface on the camera body.

[0008]

When the drive ring is rotated, the first projection and the second projection are pushed in conjunction with the first engagement portion and the second engagement portion, and the first blade group and the second blade are moved. Are opened and closed, and the first protrusion and the first engagement portion and the second protrusion and the second engagement portion are located on the same side in the lens barrel barrier, so that the occupied space is small.

Further, when the barrier for the lens barrel is mounted on the camera body, the conduction terminal of the open / close recognition switch can be connected to the connection terminal on the camera body regardless of the mounting angle.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIGS. In FIG. 1, reference numeral 1 denotes a lens barrel, and 2 denotes a barrier for the lens barrel according to the present embodiment, which is fixed to the tip of the lens barrel 1. In the barrier 2 for a lens barrel shown in FIG. 2, 3 is a ring-shaped front frame, 4 is a ring-shaped rear frame, and 5 is disposed between the frames 3 and 4, and rotates around the optical axis. A movable drive ring, 6 is a drive ring 5
Are a pair of operation knobs fixed at 180 ° symmetrical positions on the outer peripheral portion of the control panel.

Reference numeral 7 designates a first blade having three blades 7a, 7b, 7c, each of which has a base portion coaxially mounted on the front frame 3 and a tip end portion between the blades adjacent to each other connected by a pin / slot. The blade group 8 is a pivot pin for pivotally connecting the bases of the three blades 7a, 7b, 7c coaxially. The pivot structure of the first blade group 7 and the pivot pin 8 is shown in FIG. This is shown in FIG. That is, in the structure shown in FIG. 3, the first blade group 7 is attached to the pivot pin 8 fixed to the front frame 3 as shown in FIG.
Are fitted in the rotation center holes 7d formed in the respective base portions, and the head of the pivotal support pin 8 is thermally welded via the washer 8a. With this structure, unlike the conventional example shown in FIG. 1B, the pivot structure does not require the callan 8b or the screw 8c.
The structure can be simplified.

In another pivoting structure shown in FIG. 4, a pair of protruding pieces 8d are provided on the head of the pivot pin 8 so as to face each other, and a protruding piece is provided on each base of the first blade group 7. A rotation center hole 7f having a pair of notches 7e having a shape corresponding to 8d is formed. Then, after the first blade group 7 is fitted into the pivot pin 8 with the rotation center hole 7f, the pivot pin 8 or the first blade group 7 may be rotated by about 90 °. This structure simplifies the structure and facilitates assembly.

FIG. 5 shows the connecting structure of the tips of the blades 7a, 7b, 7c. FIG. 5 shows the driving ring 5 and the first blade group 7 as viewed from the front frame 3 direction in FIG. FIG. The connection pin 7b 'planted at the tip of the blade 7b slides into the slot 7a' provided at the tip of one blade 7a,
The connection pin 7b "implanted at the tip of the blade 7b is in sliding contact with the slot 7c 'provided at the tip of the blade 7c. Here, the connection pins 7b', 7b" and the respective slots 7a ', 7
Each connection structure with c 'will be specifically described with reference to FIGS.

In FIG. 6A, the head 7b'-1 of the connecting pin 7b 'has a two-way shape obtained by cutting two opposite directions in parallel from a conventional circular one (see FIG. 6B). It has the shape of Then, the slot 7a 'is
The fitting pin 7b 'is rotated by about 90 [deg.] and crimped. Connecting pin 7
The connection structure between b ″ and the slot 7c ′ is not shown, but may be configured in the same way. In another connection structure shown in FIG. A portion 7b-1 is formed, and is erected perpendicularly to the blade direction, and the slot 7a 'may be inserted into the hook portion 7b-1 and rotated.

In FIG. 5, reference numerals 9 protrude from the base of the blade 7a in a direction opposite to the blade and protrude in the radial direction of the drive ring 5 at relatively long intervals.
The first drive pin or first protrusion is located between the first drive pin 9 and the first drive pin 9 is pushed by the fork portion 5a or 5b at the final stage of the stroke when the drive ring 5 is rotated by a predetermined angle. The blade group 7 is opened and closed.

FIG. 8 is a plan view of the drive ring 5 and the second blade group as viewed from the direction of the rear frame 4 in FIG. In the figure, reference numeral 10 denotes a second blade whose base is coaxially connected to the rear frame 4 by a pivot pin 11 similarly to the first blade group 7, and whose tip between adjacent blades is connected by a pin / slot. Since the specific structure is the same as that of the first blade group 7, detailed description thereof will be omitted. In the second blade group 10, the second driving pin 12 protrudes from the tip of the blade 10a and is sandwiched between the fork portions 5c and 5d at short intervals protruding in the radial direction of the driving ring 5. When the drive ring 12 rotates the drive ring 5 at a predetermined interval, the drive pin 12 is pushed by the fork portion 5c or 5d in all strokes to open and close the second blade group 10. I have. Here, since the first blade group 7 and the second blade group 10 are arranged at positions symmetrical with respect to the optical axis, the first and second drive pins 9 of each blade group 7, 10 are arranged. 12 and fork portions 5a, 5b and 5c
And 5d are arranged on the same side and shifted in the optical axis direction.

Reference numeral 14 denotes a click spring having a base 14a connected to the rear frame 4 (or the front frame 3) and having at its free end a projection 14b which engages with a click groove 5f of the peripheral wall 5e of the drive ring 5. By forming the rear frame 4 (or the front frame 3) integrally at the time of molding, a spring property is provided. Reference numeral 15 denotes a spring that urges the drive ring 5 in, for example, the opening direction (may be urged in the closing direction). The spring 15 causes the drive ring 5 to open and has a charged state when fully closed. The click groove 5f is engaged and locked (see FIG. 8). The click spring 14 is also useful for improving the feel. Reference numeral 16 denotes a release pin which is fixed to the click spring 14 and protrudes to the outside through a guide groove 5g formed along the peripheral wall 5e. By pressing this pin 15, the lock of the click spring 14 can be released. . Reference numeral 17 denotes a cover formed integrally with the release pin 16 and along the peripheral wall 5e to cover the guide groove 5g and prevent entry of dust and the like.

FIG. 9 shows an assembling mechanism of the drive ring 5 and the front frame 3, for example, the peripheral wall 5 of the drive ring 5.
e, a concave groove 5h provided on the outer peripheral surface of the front frame 3 and a protrusion 3a provided on the outer peripheral surface of the front frame 3 are slidably fitted at least by a rotation angle of the drive ring 5 for opening and closing operation. Is formed. With this configuration, it is possible to prevent the blade group from falling off at the time of assembly, and there is an advantage that it is not necessary to adopt a blade falling prevention mechanism using screws or the like for preventing the blade from falling off as in the related art. is there. still,
A similar mechanism is employed between the drive ring 5 and the rear frame 4.

Referring to FIGS. 1 and 5, reference numeral 18 denotes a switch having a pair of contacts 18a and 18b whose bases are fixed to the front frame 3 and connected to a control circuit (not shown) of the camera. When the blade 5 is rotated to reach the blade open position, the pin 5i implanted in the drive ring 5 presses the contact 18a against the contact 18b, thereby reducing the ON force.
And OFF otherwise.

FIG. 10 shows a rear surface of the rear frame 4, that is, a mounting surface for mounting the camera body (not shown). In FIG.
a is a ring-shaped conduction pattern that is connected via a and has a center coincident with the optical axis; 21 is a conduction pattern that is connected to the other contact 18b via a switch contact 21a and is concentric with the conduction pattern 20; When the lens barrel barrier is mounted on the camera body, each of the barriers comes into contact with a pair of connection pins (not shown) on the camera body side. Although these patterns are provided on the conductive substrate, a ring-shaped metal plate may be provided instead. With such a structure, the angle of attachment to the camera body can be arbitrarily determined when the lens barrel barrier is mounted.

The drive ring 5 has a fork 5 for driving the first blade group 7 and the second blade group 10.
Each of a to 5d may be formed of a metal plate, and the knob 6 and the pin 5i for operating the switch 18 may be formed by mold outsert molding. Also, regarding the pin-slot connection of the blade interlocking portion of each of the blade groups 7 and 10, an elastic member such as rubber is mounted in the pin or the slot to such an extent that the sliding thereof is not hindered, and the occurrence of operation backlash and abnormal noise during operation is generated. May be prevented.

Since this embodiment is constructed as described above, the first drive pin 9 of the first blade group 7 is in contact with the fork 5a in the closed state as shown in FIG. At this time, as shown in FIG. 8, the spring 15 is in the charged state, the projection 14b of the click spring 14 is engaged with the click groove 5f, and the drive ring 5 is in a semi-fixed state. When the release pin 16 protruding from the drive ring 5 is pressed, the projection 14b of the click spring 14 is moved to the click groove 5f.
8, the drive ring 5 rotates in the opening direction by the urging force of the spring 15 (rightward rotation in FIG. 5, FIG. 8).
Then turn left). Then, in the initial region within the rotation range of the drive ring 5 at a predetermined angle, the fork portion 5 b
, The first blade group 7 is maintained in a closed state. On the other hand, as shown in FIG. 8, in the second blade group 10 in the closed state, the second drive pin 12 sandwiched between the forks 5 c and 5 d is rotated according to the rotation of the drive ring 5. , Each blade of the second blade group 10 is
In conjunction with the rotation of the blade, the blades 10a to 10c are sequentially folded and opened. Then, when the drive ring 5 reaches the final region of the rotation range, the fork portion 5b comes into contact with the first drive pin 9 of the first blade group 7 and pushes the same, and the respective blades 7a
７7c is rapidly folded.

In this way, the two blade groups 7, 10 are quickly folded, and the lens barrel barrier is opened.
At this time, the switch 18 is turned ON by being pushed by the pin 5i of the drive ring 5, and a signal is sent to the control circuit of the camera (not shown) via the conduction patterns 20 and 21 to put the camera in a photographable state.

Next, when the knob 6 is rotated against the urging force of the spring 15 in the blade open state, the drive ring 5 is rotated leftward in FIG. 5 (rightward in FIG. 8).
The first blade group 7 is expanded in conjunction with this, and the first blade group 7
a and is rapidly spread. Thus, the closed state shown in FIGS. 5 and 8 is obtained. In addition, the switch 18 is turned off by the rotation of the drive ring 5, so that the camera cannot take a picture.

As described above, according to this embodiment, the interlocking mechanism between the drive ring 5 and the first blade group 7 and the second blade group 10 is provided only on one side in the lens barrel barrier. Therefore, the space occupied by the interlocking mechanism during the opening / closing operation can be reduced, the configuration can be simplified, and the space for storing other components and mechanisms can be increased. A concentric conduction pattern 2 is formed on the back surface of the lens barrel barrier.
Since 0 and 21 are provided, the positioning of the mounting angle with the camera body can be set arbitrarily.

It is needless to say that the structure shown in FIGS. 3, 4, 6 and 7 can be adopted for the second blade group 10. In the above embodiment, the drive ring 5 is formed in a ring shape. However, the drive ring 5 is not limited to this shape, and may have another appropriate shape, for example, a “C-shaped” shape. For example, the space can be effectively used by utilizing the above structure. still,
The drive ring 5 constitutes a drive member, the fork portions 5a and 5b serving as first engagement portions, and the fork portions 5c and 5c.
d constitutes each of the second engagement portions. Also, conduction pattern 2
0, 21 and the metal plate constitute a conduction terminal.

[0027]

As described above, the barrier for the lens barrel according to the present invention includes an interlocking mechanism between the first projection of the first blade group and the first engagement portion of the drive member, and the second blade. Since the interlocking mechanism between the second protrusion of the group and the second engagement portion of the drive member is provided on the same side in the barrier, the configuration is simplified, the occupied space is reduced, and other It has a practically important advantage that it can accommodate components and mechanisms.
In addition, since the conduction terminal of the open / close recognition switch is concentrically attached to the mounting surface of the lens barrel barrier with the camera body, the mounting angle of the lens barrel barrier to the camera body can be set arbitrarily. This has the advantage that assembly is facilitated.

[Brief description of the drawings]

FIG. 1 is a perspective view of a lens barrel having an embodiment of a barrier for a lens barrel according to the present invention.

FIG. 2 is an exploded perspective view of a barrier for a lens barrel according to an embodiment.

FIGS. 3A and 3B are diagrams showing a pivotal connection structure between a first blade group and a pivot pin, wherein FIG. 3A relates to the present embodiment and FIG.

FIGS. 4A and 4B are diagrams showing another pivotal connection structure between the first blade group and the pivot pins, wherein FIG. 4A is a plan view and FIG.

FIG. 5 is a plan view showing a first blade group and a drive ring as viewed from a front frame side in FIG. 2;

6A and 6B are diagrams showing a pin-slot connection between two blades, wherein FIG. 6A is a diagram showing a plane and a cross section of the present embodiment, and FIG. 6B is a diagram showing a plane and a cross section of a conventional example, respectively.

FIGS. 7A and 7B are diagrams showing another configuration example showing a pin-slot connection between two blades, wherein FIG. 7A is a plane view, FIG.
(C) is a figure which shows each hook part.

FIG. 8 is a plan view showing a second blade group and a drive ring as viewed from the rear frame side of FIG. 2;

FIG. 9 is a side view of a main part showing a mechanism for attaching the drive ring to the front frame.

FIG. 10 is a diagram showing a mounting surface of a lens barrel barrier to a camera body.

[Explanation of symbols]

 3 Front Frame 4 Rear Frame 5 Drive Ring 5a Fork 5b Fork 5c Fork 5d Fork 7 First Blade Group 9 First Drive Pin 12 Second Drive Pin 10 Second Blade Group 20, 21 Conduction Pattern

Claims (2)

(57) [Scope of request for utility model registration] A driving member is rotatably arranged around an optical axis between a first frame and a second frame, and a base is coaxially pivotally connected to the first frame. The blade group and the second blade group whose base is pivotally coaxially connected to the second frame are respectively linked to a driving member, and the first and the second members are rotated by rotating the driving member. In the lens barrel barrier configured to open and close the second blade group, the first blade group is formed by a first projection provided near the base and a first engagement portion formed on the driving member. A lens mirror, wherein the second blade group is interlocked with each other by a second projection provided at a blade tip and a second engagement portion formed on the driving member. Barrier for torso. 2. A base mounted on a first frame by rotating a drive member mounted on a camera body and disposed between the first and second frames around an optical axis. In a barrier for a lens barrel, a first blade group and a second blade group whose base is pivotally attached to a second frame are opened and closed, and the open state is detected by an open / close recognition switch. A barrier for a lens barrel, wherein a conduction terminal of an open / close recognition switch is concentrically installed on a mounting surface of the lens barrel.