JPH03107937A - Lens barrier device for camera - Google Patents

Abstract

PURPOSE:To accurately obtain the precise opening and closing action of a barrier and to prevent a lens barrel part from being made large at the same time by directly controlling the driving of a barrier driving member with the aid of a lens driving member and simultaneously interlocking both members each other through the elastic force of an elastic member. CONSTITUTION:The lens driving member 11 and the barrier driving member 4 are interlocked each other only at a prescribed area through first and second engagement means 10 and 12 which can form engagement relation using the elastic force. Therefore, a mechanical output which is outputted by the lens driving member 11 is directly transmitted to the barrier driving member 4 in the prescribed area. Thus, the precise and accurate opening and closing action of lens barriers 2 and 3 is realized in the area. Besides, since the engagement relation of the first and the second engagement means 10 and 12 is formed by using the elastic force, the space occupied by the respective means need not be specially formed when they are not engaged each other. Therefore, the first and the second engagement means 10 and 12 are constituted within the lens driving member 11 and the shape of the lens barrel is made small.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a camera lens barrier device provided on the front surface of the lens to protect the photographic lens, and in particular to a camera lens barrier device in which the opening/closing operation is directly performed by a lens driving member that drives the lens. The present invention relates to a controlled camera lens barrier device.

Conventional technology In recent years, in the field of compact cameras, cameras themselves have become smaller and smaller, and cameras that can set multiple focal lengths and are equipped with zoom lenses have become commonplace. There is.

For this reason, in order to reduce the size of the lens barrier device that protects the photographic lens and to cope with the large protrusion of the lens from the camera body, for example,
As disclosed in Japanese Patent Application Laid-Open No. 63-95426 or Japanese Patent Application Laid-Open No. 63-194213, etc.
They are now being installed inside the lens barrel rather than on the camera body side.

The first proposal includes a lens drive ring that is rotatably driven by a motor to move the photographic lens holding frame between the rearmost photographable position and a storage position further back, that is, to move the collapsible section. A lens barrier mechanism is disclosed that opens and closes a lens barrier in conjunction with the rotational movement of a control section following a collapsing section.

That is, the lens driving member is provided with a closing protrusion that can control the rotation of an appropriate interlocking lever, and when the lens driving member is moved to move the lens to the section following the collapsing section, the interlocking lever is rotated, and the lens barrier is rotated. The barrier closed state is obtained by moving the lens barrier driving member, which normally biases the lens barrier in the open direction, against the biasing force.

The next proposal includes a lens cover opening/closing means that controls the operation of the lens cover by moving the interlocking member from one end of the interlocking member that interlocks the focal length switching mechanism to the motor to a predetermined intermediate position;
A camera is disclosed that is provided with a linking means for operating a focal length switching mechanism between the intermediate position and the other end.

That is, by directly associating the operation bottle provided in the lens drive member, which is the interlocking member, with the lens cover drive member that always biases the lens cover in the open direction, the lens drive member can be moved straightly or in a part of the rotational movement range. The operating pin and the lens cover drive member are configured to be interlocked, and this configuration allows the lens cover to be opened and closed.

The final proposal includes a lens movement cam groove formed in an electrically driven zoom drive frame for moving a movement frame to which a lens group is fixed, and for retracting the movement frame rearward. A zoom lens barrel is disclosed that is provided with a storage cam groove and includes a barrier drive member that controls opening and closing of a lens barrier in conjunction with a cam pin that moves within the storage cam groove.

That is, it has a barrier drive lever that comes into contact with the cam bin that has moved into the storage cam groove, and this barrier drive lever controls the operation of a driven lever fixed to a drive plate that drives the barrier to open or open the barrier. Obtaining a closed state.

Problems to be Solved by the Invention In all of the conventional lens barrier devices disclosed in the above-mentioned proposals, the lens barrier device is disposed in the lens barrel, and its opening and closing depends on the operation of a lens drive member that moves the lens. As a result, it is possible to cope with large protrusions of the lens barrel from the camera body.

However, if we look at the opening/closing structure of the lens barrier in more detail, it still has the following disadvantages.

The first and last proposed devices are equipped with appropriate interlocking levers or barrier drive levers for moving the lens barrier drive member, that is, they use an intermediate member, so they require storage space within the lens barrel. However, this method has the disadvantage that the lens barrel becomes large.

Furthermore, since the driving force of the electric drive source is transmitted to the barrier via an intermediate member, there is some concern about obtaining reliable barrier opening/closing operations with high precision. In particular, the last proposal is that in recent years, macro functions and collapsible barrel functions have become commonplace, and there is a strong demand for further miniaturization, so the range in which the cam grooves formed in the zoom drive frame are formed has been limited to a narrow range. Considering this, it seems that it will become increasingly difficult to obtain reliable barrier opening/closing operations.

On the other hand, the second proposed device directly controls the drive of the lens cover drive member using an operation bin provided on the lens drive member that moves linearly or rotationally, so it is fundamentally different from the previous proposal. does not require intermediate parts, but
It is necessary to provide a space within the lens barrel that takes into consideration the movement locus of the operating pin based on the movement of the lens drive member, and this proposal, like the previously mentioned proposal, has the disadvantage of increasing the size of the lens barrel. ing. For example, it is possible to prevent the enlargement to some extent by forming an appropriate escape groove in the moving frame, etc. to create a space that takes into consideration the movement trajectory of the previous operation bin, but in this case, there is a new risk of light leakage. Or,
Further, it is thought that disadvantages such as processing becomes complicated may occur, and it cannot be said that this method is particularly preferable for practical use.

The present invention was made in consideration of the above-mentioned points, and
The driving of the barrier driving member is directly controlled by the lens driving member, and the above-mentioned two members are interlocked through the elastic force of the elastic member, so that reliable opening/closing of the barrier can be achieved with high precision, and the lens barrel can be made larger. An object of the present invention is to provide a lens barrier device for a camera that can prevent this.

Means for Solving the Problems A camera lens barrier device according to the present invention includes cam grooves that engage with cam pins provided on a plurality of moving frames that hold lens groups, and moves the moving frames in the optical axis direction. A lens driving member having a lens driving member and a barrier driving member having a cam portion that comes into contact with a lens barrier and an opening/closing pin provided on the lens barrier are rotatable around appropriate positions, and are located in front of the forwardmost movable frame. a barrier holding means integrally provided with the forwardmost moving frame and inscribed in the lens driving member; a frame body; an elastic member housed within the frame body; and a barrier holding means housed within the frame body. a click pin, the tip of which is always urged by the elastic member so as to protrude outside the frame, and the first engaging means is formed on either the lens driving member or the barrier driving member; The above-mentioned first part of both members
The engaging means is formed on the side where the engaging means is not formed, and engages with the first engaging means only until the lens driving member moves from the reference position before photographing to a predetermined position, and drives the lens driving member. and second engagement means for transmitting the mechanical output at the time to the barrier drive member.

Function: Since the camera lens barrier device according to the present invention is configured as described above, the first engagement means and the second engagement means are engaged until the lens drive member rotates from the reference position before photographing to the predetermined position. Therefore, during the above period, the mechanical output due to the rotational movement of the lens drive member is directly transmitted to the barrier drive member, and the barrier drive member also rotates in conjunction with this. As a result, the opening/closing operation of the barrier is controlled by the relationship between the opening/closing pin provided on the lens barrier and the cam portion of the barrier drive member.

On the other hand, when the lens drive member rotates beyond a predetermined position, the first engagement means and the second engagement means are disengaged, and the click bin is attached between the two members by the elastic member. It went against the forces and was housed inside the frame,
In other words, the lens driving member and the barrier driving member are in an independent relationship with each other, and the mechanical output is not transmitted to the barrier driving member. As a result, the barrier driving member does not rotate in conjunction with the lens driving member, and the barrier driving member does not rotate in conjunction with the lens driving member. Opening and closing operations are not controlled.

Embodiments Hereinafter, embodiments of the lens barrier device for a camera according to the present invention will be described.

FIG. 1 is a schematic exploded perspective view of essential parts showing an embodiment of a lens barrier device for a camera according to the present invention.

The barrier tube 1 has a hollow cylindrical shape with a front opening 1a and a rear opening 1b, and has a lens barrier 2.3 inside the front opening 1a, and opening/closing pins 2a installed in each of the lens barriers 2.3. , 3a, a barrier ring 4 which is a barrier driving member having cam portions 4a and 4b that come into contact with the lens barrier 2.3, and a spring 5a that always biases the lens barrier 2.3 in the open direction;
5b is held via a barrier stand 6, that is, it forms a barrier holding means.

The opening/closing pins 2a, 3 planted on the lens barrier 2.3
As is clear from the drawing, the contact between the cam portions 4a and 4b of the barrier ring 4 is made through the insertion holes 6c and 6d of the barrier stand 6.
On the other hand, the opening/closing state of the lens barrier 2.3 is controlled by the change in the contact state caused by the rotation of the barrier ring 4.

Further, the lens barrier 2.3 and the barrier ring 4 are held so as to be rotatable about shafts 6a, 6b or the optical axis, respectively, which are set up on the barrier stand 6.

Furthermore, the barrier tube 1 is equipped with a zooming cam 11 which will be described later.
The frontmost movable frame of a plurality of movable frames (not shown) that holds a lens group that is inscribed in the interior and that is moved by the zooming cam 11 is integrally built in, and the frontmost movable frame is integrally built in and held by the zooming cam 11. It moves straight forward and backward along the optical axis together with the forward moving frame.

The barrier ring 4 is integrally provided with an extension arm 4C extending rearward along the inner circumferential surface of the barrier cylinder 1, and a first engagement means 10 is formed at the tip of the extension arm 4C. .

The first engaging means 10 includes a frame 7 and a spring 8 which is an elastic member housed in the frame 7, as shown in FIG. and a click bin 9 housed within the frame 7 and always biased by the spring 8 so that its tip 9a protrudes outside the frame 7.

In addition, the first engaging means 10 is shown in FIG.
As is clear from a), the barrier ring 4 is located within the notch IC provided in the barrier cylinder 1, and therefore the rotation of the barrier ring 4 is caused by the first rotation.
It is controlled within an appropriate range by contact between the engaging means 10 and the notch and both ends 1d and le of the portion IC. As is clear from FIG. 2(a), the tip 9a of the click pin 9 of the first engaging means 10 is formed into a spherical shape, and the barrier tube 1
It also protrudes from the outer peripheral surface of.

The zooming cam 11, which is a lens driving member that moves a plurality of movable frames (not shown) holding lens groups in the optical axis direction, has a hollow cylindrical shape and engages with a cam pin provided on each of the movable frames. a plurality of matching cam grooves 11a;
llb etc. and the click pin 9 of the first engaging means 10 described above.
An engagement hole 12 is formed as a second engagement means that can engage with the tip end 9a of the barrier tube 1 only in a predetermined state, and as is clear from FIG.
is inscribed.

Now, in the case shown in FIG. 2(a) where the engagement hole 12 and the tip 9a of the click bin 9 are engaged, the barrier ring 4 has a Since the output is directly transmitted, the barrier ring 4 can rotate in conjunction with the barrier ring 4.

However, as described above, the rotation is caused by the first engagement means 10.
and the notch IC, and if the amount of rotational movement of the zooming cam 11 exceeds the control range based on the above relationship, the engagement is released by the movement of the click bin 9 against the biasing force of the spring 8, That is, the supply of the mechanical output is stopped, and thereafter the interlocking relationship between the barrier ring 4 and the zooming cam 11 is lost.

On the other hand, in order to perform the opening/closing operation of the lens barrier 2.3 with high precision, it goes without saying that it is necessary to perform the opening/closing operation within the above control range in which the zooming cam 11 can directly control the barrier ring 4. Therefore, in the present invention, the shape of the notch IC that defines the control range and the shape of the cam parts 4a and 4b that contact the opening/closing bins 2a and 3a of the lens barrier 2.3 are taken into consideration, respectively, taking into consideration the above-mentioned needs. The lens barrier 2.3 is set so that the lens barrier 2.3 is reliably opened and closed by rotation of the barrier ring 4 within the above control range.

Furthermore, it goes without saying that it is desirable that the opening/closing operation of the lens barrier 2.3 be performed at a time not related to photographing, and in the present invention, the above control range is limited to the zooming cam 1.
1 corresponds to an appropriate range including the entire movement section from the reference position before photographing to setting the lens to the wide end.

That is, the engagement hole 12 described above is connected to the zooming cam 1.
1 only within an appropriate range including the entire movement range from the reference position before shooting to setting the lens to the wide end.
It is formed in such a position and shape that it can maintain the engaged state with the tip end 9a of the click pin 9.

Below, the operation of the embodiment shown in FIG. 1 will be explained as shown in FIG.
This will be explained with reference to a) and (b).

3(a) and 3(b) are schematic plan views of main parts of the assembled state of one embodiment of the lens barrier device according to the present invention shown in FIG. In the closed state corresponding to the illustrated state, the figure (b) shows the open state.

Now, as is clear from FIG. 3(a), the lens barrier device according to the present invention has an opening/closing bin 2a of the lens barrier 2.3.
, 3a and the cam parts 4a, 4b are in contact with the cam part 4a s
The closed state is formed by rotating the barrier ring 4 until the lens barrier 4b is on the lens barrier 4b, that is, by rotating the lens barrier 2.3 clockwise against the biasing forces of the springs 5a and 5b. At this time, the click pin 9 of the first engagement means 10 and the engagement hole 12 of the second engagement means are engaged, and the rotation of the barrier ring 4 is caused by the zooming cam 1.
What is done in conjunction with the rotational movement of 1 is as described above.

When the zooming cam 11 is rotated clockwise from the state shown in FIG. 3(a), the click bin 9
Since the barrier ring 4 is engaged with the engagement hole 12, the barrier ring 4 also rotates clockwise, and the contact state between the cam portions 4a, 4b and the opening/closing bins 2a, 3a is gradually released. (It turns out.

In the abutting state, the first engaging means 10 is in contact with the barrier cylinder 1.
The barrier ring 4 comes into contact with one end 1e of the notch IC.
The zooming cam 11 will be completely released by the time it becomes impossible to move in conjunction with the zooming cam 11.

The release of the contact state between the cam parts 4a, 4b and the opening/closing bins 2a, 3a means that the lens barrier 2.3 is
This is nothing more than a counterclockwise rotation operation due to the biasing forces of a and 5b, that is, the lens barrier 2.3 performs an opening operation, and as a result, as shown in FIG. 3(b). This will set the open state.

In the state shown in FIG. 3(b), the zooming cam 11 is further rotated clockwise from the state in which the lens barrier 2.3 is set to the open state, and the tip 9a of the click pin 9 is rotated. This shows a state in which the click pin 9 is in contact with the inner peripheral surface of the zooming cam 11, that is, a state in which the click pin 9 is housed in the frame 7 by the elastic force of the spring 8 and is disengaged from the engagement hole 12 described above. ing.

Even when the above-mentioned engagement is released, the lens barrier 2.3 does not return to its original state and remains open, while the zooming cam 11 has a maximum focal length (
By rotating the lens until the telephoto end) is set, the movement of a plurality of moving frames (not shown) in the direction of the optical axis using the cam groove 11a etc. can be controlled, that is, the well-known zooming operation can be performed freely. .

At this time, the tip end 9a of the click bin 9 comes into contact with the inner circumferential surface of the zooming cam 11, that is, it slides on the inner circumferential surface.

Also, the setting of the shortest focal length (wide end) is shown in Figure 3 (b).
), or at an appropriate time when the zooming cam 11 is further rotated clockwise.

When the zooming cam 11 is rotated counterclockwise from the state where the well-known zooming operation described above is performed,
A plurality of moving frames move in the direction of setting the wide end, and at the same time, the barrier tube 1 that integrally houses the frontmost moving frame among these moving frames also moves along the optical axis.

That is, the first engagement means 1 provided on the barrier ring 4
The tip 9a of the click bin 9 of 0 is the zooming cam 11
The zooming cam 11 slides on the inner circumferential surface of the zooming cam 11, and gradually approaches the engagement hole 12, which is the second engagement means provided in the zooming cam 11, and finally engages with the engagement hole 12.

When the tip 9a of the click bin 9 and the engagement hole 12 engage and the zooming cam 11 further rotates counterclockwise, the mechanical output due to the rotation is directly supplied to the barrier ring 4, and therefore The barrier ring 4, which had not rotated until then, will now rotate counterclockwise.

When the barrier ring 4 rotates counterclockwise, its cam portions 4a and 4b move toward the lens barrier 2.3, as described above.
The lens barrier 2.3 comes into contact with the opening/closing bins 2a, 3B, and rotates the lens barrier 2.3 clockwise against the biasing force of the springs 5a, 5b, so that the lens barrier 2.3 gradually closes and finally The closed state shown in FIG. 3(a) is reached.

The above operations are a series of operations of the lens barrier device according to the present invention, and here, the lens barrier 2.
3 and the zooming cam 11 is schematically shown.
The result will be as shown in the figure.

That is, when the zooming cam 11 is at the reference position, the lens barrier 2.3 is in a closed state, and the zooming cam 11
When the lens barrier 2.3 moves (rotates) so as to reach the wide end setting position, the lens barrier 2.3 starts to move at the same time as the movement starts, as shown by the solid line, or for an appropriate time, as shown by the broken line, and gradually opens. To go. This opening operation will be completed by the time the zooming cam 11 reaches the wide end setting position at the latest. In addition, lens barrier 2
．． 3 is released, the engagement between the click bin 9 and the engagement hole 12 is released, and therefore the zooming cam 11 and the lens barrier 2.
As explained earlier, the interlocking relationship with 3 is also canceled.

The zooming cam 11 moves between the wide end and the tele end in order to set the desired focal length, but at this time the lens barrier 2.3 remains open and the click pin remains open. The distal end portion 9a of the zoom cam 9 is maintained in a state in which it is in contact with the inner peripheral surface of the zooming cam 11 by the elastic force of the spring 8, that is, in a state in which it is housed in the frame body 7.

On the other hand, when the zooming cam 11 moves toward the reference position, the click bin 9 and the engagement hole 12 are engaged again at an appropriate position where the zooming cam 11 exceeds the wide end setting position toward the reference position, so that the lens The barrier 2.3 gradually starts to close from the above-mentioned appropriate position, and of course, when it returns to the standard position, it will be in a completely closed state.

Effects of the Invention The lens barrier device according to the present invention allows the lens driving member and the barrier driving member to be interlocked only in a predetermined region via first and second engaging means that can form an engaging relationship using elastic force, Therefore, the mechanical output from the lens drive member is directly transmitted to the barrier drive member in this predetermined region, and as a result, the lens barrier can be opened and closed reliably and with high precision in the above region. have.

Further, since the engagement between the first and second engagement means is formed using elastic force, there is no need to specially form a space occupied by each means when they are not engaged, and therefore the lens The first and second engaging means can be configured within the drive member, and as a result, the outer diameter of the lens drive member can be reduced, that is, the shape of the lens barrel can be made smaller. .

[Brief explanation of drawings]

FIG. 1 is a schematic exploded perspective view of essential parts showing an embodiment of a lens barrier device for a camera according to the present invention, and FIGS. 2(a) and (b)
is the drawing number 1 in the assembled state of the embodiment shown in Fig. 1.
FIGS. 3(a) and 3(b) are a partial cross-sectional view and partial view of the vicinity of the first engaging means indicated by 0, and FIGS. FIG. 4 is a schematic diagram showing the operational relationship between the lens barrier 2.3 and the zooming cam 11 in the embodiment shown in FIG. 1, respectively. 1... Barrier tube, 2.3... Lens barrier, 4...
・Barrier ring, 5 as 5 b...Spring, 6...
・Barrier stand, 7...frame body, 8...spring, 9.
...Click pin, 10...First engagement means, 11...
-Zooming cam, 12...engaging hole.

Claims (1)

[Claims] a lens driving member that includes a cam groove that engages with cam pins provided on a plurality of moving frames that hold lens groups and moves the moving frames in the optical axis direction; a lens barrier; and an opening/closing pin provided on the lens barrier; Barrier drive members each having abutting cam portions are rotatable around appropriate positions, and are held so as to be positioned in front of the forwardmost moving frame, and are integrally provided with the forwardmost moving frame; Further, barrier holding means inscribed in the lens driving member;
The lens drive member or A first engaging means is formed on either one of the barrier driving members, and a first engaging means is formed on the one of both members where the first engaging means is not formed, and the lens driving member is moved from a reference position before photographing to a predetermined position. engaging with the first engaging means only until moving to the position;
a second engagement means for transmitting a mechanical output when driving the lens driving member to the barrier driving member.