JPH07159858A - Hood fitting device - Google Patents

Abstract

PURPOSE:To obtain a device capable of fixing a hood on a lens barrel at the time of fitting the hood and easily removing it by providing an energizing member for energizing in an optical axial direction and a projecting part on one of the lens barrel and the hood and a recessed part in the optical axial direction engaged with the projecting part on the other. CONSTITUTION:The bayonet pawl 21 of the hood 20 is inserted in a position where the pawls are not overlapped on the lens barrel 10 and further, the hood 20 is rotated around an optical axis. A rotation restraining part 22 rides across the bayonet pawl 11 of the lens barrel 10, while the hood 20 is energized in a thrusting direction by the elastic part of the lens barrel 10. The rotation restraining part 22 of the hood 20 is engaged with the receiving part for restraining the rotation 12 of the lens barrel 10, to complete a fitting action. On the other hand. at the time of removing the hood 20, it is moved in the optical axial direction against the energizing force of the pressing part 13 of the lens barrel 10, to disengage the rotation restraining part 22 from the receiving part for restraining the rotation 12 and further, rotated around the optical axis, in a removing direction, to be removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hood mounting device having a bayonet structure, a lens barrel and a hood.

[0002]

2. Description of the Related Art Conventionally, a bayonet structure for attaching a hood has a lens barrel as shown in FIG.
It is constituted by a hood as shown in (B), and is explained by showing a developed view in FIG. 9 and a perspective view in FIG. 7.

In FIG. 8A, 60 is a conventional lens barrel, 61 is a bayonet claw, 61a is a stopper part, 62 is a click part, and 63 is a sliding part.

Next, in FIG. 8B, 70 is a hood, 71 is a bayonet claw when the hood is used, 71a is a charging part when the hood is used, 72 is a bayonet claw when the hood is stored, and 72a is a hood. A hood side stopper section 73 is a charging section at the time of storage, and a portion where the bayonet 71 when using the hood and the bayonet claw 72 when storing the hood overlap each other is a hood side stopper section 73, and this configuration develops the same shape in the diagonal direction. It has a two-claw bayonet.

Next, the operation will be described. 7 and 9, the hood 70 is inserted into the lens barrel 60 as indicated by the arrow 80 indicating the optical axis direction, and then the hood 70 is rotated in the direction of the arrow 81 indicating the optical axis rotation direction. When the hood is used, the charging portion 71a is the sliding portion 6 of the lens barrel 60.
3 is slid and engaged with the click portion 62, and at the same time, the hood-side stopper portion 73 contacts the stopper portion 61a of the lens barrel 60, and the attachment of the hood is completed.

[0006]

However, in the above-mentioned conventional example, when the user takes a picture with the hood attached or when the hood is subjected to some external impact during transportation,
There was a drawback that the hood came off the click part and the hood fell off and was lost. Also, in the case of a petal-type hood that effectively cuts harmful light to the shooting screen, the shooting light flux is eclipsed due to the hood being slightly rotated from the click position due to being removed from the click part due to external impact. There was a drawback that

The present invention provides a hood mounting device in which the hood is fixed to the lens barrel when the hood is attached and the detaching operation is easy.

[0008]

According to the present invention, there is provided a lens barrel having a first bayonet claw and a hood having a first bayonet claw and a second bayonet claw capable of being polymerized, and the hood is A bayonet structure in which the first and second bayonet claws are inserted into the lens barrel at a non-overlapping position that is displaced by a predetermined angle from the overlapping position, and are held to the lens barrel by rotating to the overlapping position. In the hood mounting device having the above, a biasing member for biasing in the optical axis direction is provided on at least one of the lens barrel and the hood, and a projection in the optical axis direction is provided on at least one of the lens barrel and the hood. By providing a recess on the other side in the optical axis direction with which the protrusion engages at the position where the first and second bayonet claws overlap, the first and second When the urging force of the urging member is applied in the direction in which the protrusion and the recess are pressed against each other at the overlapping position of the bayonet claw, and the hood is pushed in the optical axis direction with respect to the lens barrel, Since the urging force of the urging member can be released, the hood is fixed to the lens barrel when the hood is attached and the detaching operation is facilitated.

Further, since the urging member is integrally formed with the hood or the lens barrel, it can be simply constructed.

[0010]

1 is a perspective view of a hood and a lens barrel as a first embodiment of the present invention, and FIG. 2 is a first embodiment of the present invention.
FIG. 3 is a sectional view of a main part of a lens barrel of an embodiment of the present invention.
FIG. 6 is a development view illustrating a procedure for attaching and detaching the hood of the example of FIG.

In FIG. 1, 10 is a lens barrel,
Reference numeral 11 denotes a bayonet claw that is a first bayonet claw for attaching a hood, 12 is a rotation lock receiving portion that is a recessed portion, 1
Denoted at 3 is a pressing portion for pressing the hood in the optical axis direction, and this structure has a bayonet structure of two claws arranged diagonally. Further, 20 is a hood, 21 is a hood-side bayonet claw which is a second bayonet claw, and 22 is a rotation locking part which is a protrusion, which are arranged diagonally like the lens barrel 10. There is. Further, in the sectional view of the main part of FIG. 2, the pressing portion 13 of the lens barrel 10 is an urging spring 1 which is an urging member.
4 has a structure in which a biasing force always acts in the optical axis direction.

Next, the desorption procedure will be described with reference to the development view of FIG. The bayonet claw 2 of the hood 20 as shown in FIG.
Insert 1 into the lens barrel 10 at a position where the nails do not overlap,
Further, as shown in FIG. 3B, the hood 20 is rotated around the optical axis. In FIG. 3C, the hood 20 is biased in the thrust direction by the elastic portion of the lens barrel 10,
The rotation locking portion 22 is the bayonet claw 11 of the lens barrel 10.
Get over. In FIG. 3D, the rotation locking portion 22 of the hood 20 is engaged with the rotation locking receiving portion 12 of the lens barrel 10, and the mounting operation is completed.

On the other hand, when the hood 20 is detached from the lens barrel 10, the hood 20 is moved in the optical axis direction against the urging force of the holding portion 13 of the lens barrel 10 to rotate the locking portion 22.
The hood 20 after releasing the engagement of the rotation lock receiving portion 12
Rotate around the optical axis in the removal direction to remove.

In the present invention, the holding portion 1 of the lens barrel 10 is used.
Although 3 is a separate structure by the biasing spring 14, this is the same even if the pressing portion itself is an elastic material such as rubber, and further, the lens barrel is formed to have an elastic force. The same effect can be obtained even with the integrated structure.

FIG. 4 is a perspective view of a hood and a lens barrel which are the second embodiment of the present invention, and FIG. 5A is a front view of the lens barrel which is the second embodiment of the present invention. FIG. 5 (B)
Is a front view of a hood which is a second embodiment of the present invention, and FIG. 6 is a view for explaining a procedure for attaching and detaching the hood.

In FIG. 4, reference numeral 40 is a lens barrel according to the second embodiment of the present invention, and 41 is a first lens barrel for attaching a hood.
No. 42 is a bayonet claw, and 42 is a rotation lock receiving portion which is a dent, and this structure has a two-claw bayonet structure which is also arranged diagonally. Further, 50 is a hood which is the second embodiment of the present invention, 51 is a hood side bayonet claw which is a second bayonet claw, 52 is a rotation locking part which is a protrusion, and 53 is integrally molded. It is an elastic portion as a biasing member, and is arranged in a diagonal direction like the lens barrel 40.

The procedure for attaching and detaching the hood device is shown in FIG. 6. The holding portion 13 which is composed of the holding portion 13 and the biasing spring 14 on the lens barrel 10 side in the first embodiment is the hood in this embodiment. It is the same except that the elastic portion 53 is integrally formed on the 50 side.

[0018]

As described above, according to the present invention,
A lens barrel having a first bayonet claw and a hood mounting device having a bayonet structure configured by a hood having a first bayonet claw and a second bayonet claw capable of overlapping with each other, at least the lens barrel and the hood. An urging member for urging in the optical axis direction is provided on either one of the lens barrel and a projection in the optical axis direction is provided on at least one of the lens barrel and the hood, and the projection is provided on the other of the first and second Since the recessed part in the optical axis direction that engages at the position where the bayonet claws overlap is provided, it can be mounted simply by rotating it in the same way as before when attaching the hood, and when detaching it, attach it to the lens barrel. On the other hand, the hood is pushed in the direction of the optical axis against the urging force of the urging member, and the hood can be rotated without releasing the engagement between the protrusion and the recess, which is the recess engaged with the protrusion. Na Because the way, the hood by an impact or the like is prevented from inadvertently rotating hoods lost, it is possible to eliminate the screen vignetting during petal type hood.

Further, since the urging member is formed integrally with the lens barrel and the hood, the structure can be simplified and the number of parts can be reduced, so that the productivity can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view of the present invention.

FIG. 2 is a sectional view of an elastic portion of a lens barrel embodying the present invention.

FIG. 3 is a development view of an operation procedure according to an example of implementing the present invention.

FIG. 4 is a perspective view according to another embodiment.

FIG. 5 is a front view according to another embodiment.

FIG. 6 is a developed view of an operation procedure according to another embodiment.

FIG. 7 is a perspective view of a conventional example.

FIG. 8 is a front view of a conventional example.

FIG. 9 is an operation development diagram of a conventional example.

[Explanation of symbols]

 10, 40, 60 Lens barrel 20, 50, 70 Hood 11, 41 Bayonet claw 12, 42 Rotation lock receiving part 13 Elastic part 14 Energizing springs 21, 51, 71 Hood side bayonet claw 22, 52 Rotation locking part 23 Elastic part 61a Stopper part 62 Click part 63 Sliding part 71 Bayonet claw when using a hood 71a Charge part when using a hood 72 Bayonet claw when storing a hood 71a Charge part when storing a hood 73 Hood side stopper part

Claims (5)

[Claims] 1. A lens barrel having a first bayonet claw and a hood having a second bayonet claw capable of overlapping with the first bayonet claw, the hood being the first and second bayonet claws. In a hood mounting device having a bayonet structure that is inserted into the lens barrel at a non-overlapping position that is displaced by a predetermined angle from the overlapping position and is held with respect to the lens barrel by rotating to the overlapping position, the lens At least one of the lens barrel and the hood is provided with an urging member for urging in the optical axis direction, at least one of the lens barrel and the hood is provided with a protrusion in the optical axis direction, and the other is provided with the protrusion. By providing a recessed portion in the optical axis direction that engages at a position where the first and second bayonet claws overlap, at a position where the first and second bayonet claws overlap with each other. The urging force of the urging member is applied in the direction in which the protrusion and the recess are in pressure contact with each other, and the hood is pushed in the optical axis direction with respect to the lens barrel to release the urging force of the urging member. A hood mounting device characterized in that it is made possible. 2. A lens barrel having a first bayonet claw and a hood having a second bayonet claw capable of overlapping with the first bayonet claw, the hood being the first and second bayonet claws. Is inserted into the lens barrel at a non-overlapping position displaced by a predetermined angle from the position where
In a hood having a bayonet structure that is held with respect to the lens barrel by rotating to the overlapping position, a biasing member that biases the hood in the optical axis direction is provided in the hood, and at least one of the lens barrel and the hood is provided. By providing a protrusion in the optical axis direction on one side and a recess in the optical axis direction on the other side, the protrusion engages at a position where the first and second bayonet claws overlap with each other. And at the overlapping position of the second bayonet claw, the urging force of the urging member is applied in the direction in which the projection and the recess are pressed against each other, and the hood is pushed in the optical axis direction with respect to the lens barrel. By so doing, the urging force of the urging member can be released. 3. A lens barrel having a first bayonet claw and a hood having a second spring yacht claw capable of overlapping with the first bayonet claw, the hood being the first and second bayonet claws. Is inserted into the lens barrel at a non-overlapping position displaced by a predetermined angle from the position where
In a lens barrel having a bayonet structure that is held with respect to the lens barrel by rotating to the overlapping position, a biasing member that biases the lens barrel in the optical axis direction is provided,
A projection in the optical axis direction is provided on at least one of the lens barrel and the hood, and the projection is engaged with the other at the position where the first and second bayonet claws overlap with each other. By providing the urging force of the urging member at the overlapping position of the first and second bayonet claws in the direction in which the protrusion and the recess are pressed against each other, the hood is attached to the lens barrel. A lens barrel characterized in that the urging force of the urging member can be released by pushing in the optical axis direction. 4. The hood according to claim 2, wherein the urging member is formed integrally with the hood. 5. The lens barrel according to claim 3, wherein the biasing member is integrally formed with the lens barrel.