JP2592211Y2 - Focal plane shutter setting mechanism - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focal plane shutter setting mechanism.

[0002]

2. Description of the Related Art A conventional shutter setting mechanism is disclosed in Japanese Utility Model Application Laid-Open No. Hei. In the figure, the release lever 33 is
a and is urged by a spring 34 in a clockwise direction. The release lever 33 is provided with a roller portion 33b, which is rotatably supported.
The release lever 33 is provided with a drive pin 33c, which is connected to a known group of open blades. The closing lever 35 is rotatably supported by a shaft 35a, and is urged by a spring 36 in a clockwise direction. The closing lever 35 is provided with a roller portion 35b, which is rotatably supported. Close lever 3
5 is provided with a drive pin 35c, and this drive pin 35c is connected to a known closed blade group. The first set lever 30 is rotatably supported by a shaft 30a,
A cam portion 30c is formed which comes into contact with a roller portion 31d rotatably supported by a second set lever 31, which will be described later. The second set lever 31 is rotatably supported by a shaft 31a, and is urged by a spring 32 in a counterclockwise direction. Further, the second set lever 31 is formed with a cam portion 31b that contacts the roller portion 33b supported by the opening lever 33 and a cam portion 31c that contacts the roller portion 35b supported by the closing lever 35.

In such a shutter setting mechanism, the opening lever 3 is opposed to the opening and closing springs 34,36.
3 and the closing lever 35, first, the roller 30b of the first set lever 30 is pushed leftward in the figure by a camera-side setting mechanism (not shown), so that the first
The set lever 30 is turned clockwise about the axis 30a.
As a result, the cam portion 30c of the first set lever 30 is
The second set lever 31 is rotated clockwise about the shaft 31a by contacting the roller portion 31d of the set lever 31.

With the above operation, the opening lever 33 and the closing lever 35 rotate in the setting direction, and the opening lever locking pawl 37
And the claw portions 37b and 39b of the closing lever locking claw 39, and the respective engaging portions 33 of the opening lever 33 and the closing lever 35
d and 35d are engaged, and the setting is completed.

[0005]

However, in order to reduce the size of the shutter in the vertical direction in FIG. 1 with such a conventional shutter setting mechanism, the first set lever 30 and the second set lever 31 are required. Since the operating angles of the first set lever 30 and the second set lever 31 are largely different, the roller portion 31d of the second set lever 31 and the cam of the first set lever 30 need to be improved. There is a problem that the pressure angle of the portion 30c becomes worse and the setting force becomes heavy.

[0006]

According to the present invention, there is provided a substrate having a shutter opening, a group of open and closed blades for opening and closing the shutter opening, and a drive for operating each of the blade groups. In a focal plane shutter provided with a mechanism, a first set lever which is pivotally supported by the substrate and rotates when a shutter is set, a gear mechanism which meshes with the first set lever and rotates, and which is coaxial with the first set lever. A second set lever that is rotatably supported by the gear and sets the drive mechanism by engaging with the gear. The rotation angle of the second set lever is larger than the rotation angle of the first set lever via the gear mechanism. Configuration.

[0007]

According to the present invention, by connecting the first set lever and the second set lever via the gear mechanism, the pressure angle can always be kept constant, so that the set force is reduced. In addition, since the first set lever and the second set lever are coaxially supported, it can be configured with a small space.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 are a main part plan view and a main part sectional view of the present invention. The first set lever 1 has a tooth portion 1a.
And a roller portion 1b that engages with the camera-side set member.
6 rotatably supported.

The gear 4 is rotatably supported by a substrate 26,
It has a small gear 4a and a large gear 4b, and the small gear 4a meshes with the tooth portion 1a of the first set lever 1 and the large gear 4b meshes with the tooth portion 2a of the second set lever 2 as shown in FIG. ing.

The second set lever 2 has a tooth portion 2a and a cam portion 2b which comes into contact with a roller portion 6b of an opening lever 6 described later.
And a cam portion 2c abutting on a roller portion 14c of the first closing lever 14, which will be described later, a pin 2d, and a pin 2e. Since the second set lever 2 is urged counterclockwise by the spring 5, the first set lever 1 is urged counterclockwise by the spring 5 via the second set lever 2 and the gear 4. In the state before setting shown in FIG. 1, the first set lever 1 comes into contact with the positioning member 25 implanted on the substrate 26 and stops.

The release lever 6 is rotatably supported on a substrate 26 by a shaft 6a, and includes a roller portion 6b, a drive pin 6c, an engagement portion 6d, and a spring 7 for rotating the release lever 6 clockwise. And an engaging spring hook 6e. Here, the spring hook 6e of the release lever 6, the spring 7, and a pin 8a of a brake lever A8 for a front blade described later are engaged by the spring hook 6e and the spring 7 when the release lever 6 reaches the position shown in FIG. The relationship is configured to match. Therefore, in the state of FIG. 1, the release lever 6 is not biased, and in the state of FIG. 3, the release lever 6 is biased clockwise by the spring 7.
The drive pin 6c of the release lever 6 is fitted to an arm of a known parallel link mechanism to drive a known group of open blades.
The front blade brake lever A8 has a pin 8a.
1, and is rotatably supported by the substrate 26 by the shaft 10 so as to be coaxial with the front blade brake lever B9. The release lever locking claw 12 is rotatably supported on a substrate 26 by a shaft 12a.
And an engaging portion 12c which engages with a known open iron lever, and is urged counterclockwise by a spring 13.

First closing lever 14 and second closing lever 15
Is rotatably supported on a substrate 26 by a shaft 16 so as to be coaxial. The first closing lever 14 has an engaging portion 14
a, an engagement portion 14b that engages with the second closing lever 15,
Roller portion 14c abutting on cam portion 2c of set lever
And is urged clockwise by a spring 18. The second closing lever 15 has a driving pin 15a, and is urged counterclockwise by a spring 17 to engage the first closing lever engaging portion 14b.
Is in contact with The drive pin 15a of the second closing lever 15 is fitted to an arm of a known parallel link mechanism to drive a known closing blade group. Rear blade brake lever A1
9 and a rear blade brake lever B20 are rotatably supported by a substrate 26 by a shaft 21 so as to be coaxial.
The spring 22 causes the rear blade brake lever A19 to rotate counterclockwise and the rear blade brake lever B20 to rotate clockwise.
Each is energized. Rear blade brake lever A1
Reference numeral 9 includes a cam portion 19a that comes into contact with the pin 2d of the second set lever 2, and a locking portion 19b that locks the drive pin 15a of the second closing lever 15. Brake lever B for rear wing
Reference numeral 20 includes a cam portion 20a that contacts the pin 2e of the second set lever 2, and a locking portion 20b that locks the drive pin 15a of the second closing lever 15. The closing lever locking claw 23 is rotatably supported on the base plate 26 by a shaft 23a, and is provided with a claw portion 23b which engages with the engaging portion 14a of the closing lever 14, and an engaging portion 23c which engages with a known closing iron piece lever. And is urged clockwise by a spring 24.

The operation of the shutter setting mechanism configured as described above will be described. FIG. 1 is a diagram showing a state before setting. The first set lever 1 starts rotating clockwise against the urging force by a known camera-side set member. The rotation of the first set lever 1 is transmitted to the second set lever 2 via the gear 4, and the second set lever 2 starts rotating clockwise. When the second set lever 2 rotates, first, the cam portion 2b comes into contact with the roller portion 6b of the release lever 6, and the release lever 6 starts to rotate counterclockwise, and the release lever 6 rotates first. The lock by the blade brake lever A8 and the front blade brake lever B9 is released. At this time, the spring 7 is a front blade brake lever A8.
And the biasing force of the spring is not transmitted to the release lever 6. When the opening lever 6 rotates, the driving pin 6c moves the known opening blade group in the set direction. When the second set lever 2 rotates, the pin 2d comes into contact with the cam portion 19a of the rear blade brake lever A19, and the rear blade brake lever A19 is rotated clockwise.
e comes into contact with the cam portion 20a of the rear blade brake lever B20 to rotate the rear blade brake lever B20 counterclockwise, respectively, to release the locking of the drive pin 15a of the second closing lever 15. Subsequently, the cam portion 2c of the second set lever 2 comes into contact with the roller portion 14c of the first closing lever 14, and the first closing lever 14 starts rotating counterclockwise against the spring 18, so that the second closing lever 14 starts rotating. Drive pin 1 of closing lever 15
5a moves the known closing blade group in the direction of the set.

When the second set lever 2 continues to rotate, the opening lever 6 and the closing levers 14 and 15 continue to rotate, and when the roller portion 6b reaches the state shown in FIG. Engage. Therefore, the release lever 6 is kept in the spring 7 until it is locked by the release lever locking claw 12 thereafter.
Continue turning against When the second set lever 2 is further rotated, the engaging portion 6d of the opening lever 6 is engaged with the opening lever engaging claw 12b and the engaging portion 14a of the first closing lever 14 is engaged with the closing lever engaging claw 23. The opening lever 6 and the first closing lever 14 are further rotated and then locked in order to securely lock the opening lever 6 and the first closing lever 14 respectively. The state is as shown in FIG.

Thereafter, a known camera-side set member is moved to the first position.
By retracting from the operating range of the set lever 1, the spring 5
The first set lever 1 is rotated counterclockwise via the second set lever 2 and the gear 4 by the urging force of
5 and the setting operation is completed.

When the release button of the known camera is pressed, the known open-side iron piece lever pushes the engaging portion 12c of the release lever locking claw 12, and the release lever locking claw 12
The opening 12 is disengaged from the engaging portion 6d of the opening lever 6 and the opening lever 6 is turned clockwise by the urging force of the spring 7. The rotation starts, and the drive pin 6c drives the known open blade group to start the exposure operation.

Thereafter, when the release lever 6 rotates until the roller portion 6b of the release lever 6 reaches the position shown in FIG. 2, the engagement between the spring hook 6e and the spring 7 is released, and the release lever 6 is thereafter rotated by inertia. Keep moving. Further, when the release lever 6 rotates and comes into contact with the front blade brake lever A8 and the front blade brake lever B9, the release lever 6 resists the spring 11 and the front blade brake lever A8 and the front blade brake lever B9. Is decelerated while rotating clockwise, the front blade brake lever A8 and the front blade brake lever B9 are decelerated.
Stop between them.

A predetermined time after the opening lever 6 starts to rotate, a known closing iron piece lever pushes the locking portion 23c of the closing lever locking claw 23, and the engaging portion 14 of the first closing lever 14
a is disengaged from the engaging portion 23b of the closing lever locking claw 23, the first closing lever 14 starts rotating clockwise integrally with the second closing lever 15 by the urging force of the spring 18, The drive pin 15a starts driving the known closing blade group.

First closing lever 14 and second closing lever 1
5 further rotates, and when the drive pin 15a comes into contact with the locking portion 19b of the rear blade brake lever A19 and the locking portion 20b of the rear blade brake lever B20, the driving pin 15a resists the urging force of the spring 22 and is used for the rear blade. The brake lever A19 is decelerated while rotating the brake lever A19 clockwise and the brake lever B20 for the rear blade in a counterclockwise direction.
And the rear blade brake lever B20 so as to be stopped.

[0020]

According to the structure of the present invention, since the rotation centers of the first set lever and the second set lever are arranged coaxially, the size of the shutter can be reduced. By connecting the two set levers with gears,
Since the pressure angle is always constant, no excessive force is applied, so that the set force can be reduced.

[Brief description of the drawings]

FIG. 1 shows a focal plane shutter 1 according to the present invention.
FIG. 4 is a plan view showing a state before setting according to the embodiment.

FIG. 2 shows one of the focal plane shutters according to the present invention.
FIG. 4 is a plan view showing the setting of the embodiment.

FIG. 3 is a plan view showing a setting end state of one embodiment of the focal plane shutter according to the present invention;

FIG. 4 is a partial sectional view of one embodiment of the focal plane shutter according to the present invention;

FIG. 5 is a plan view showing a conventional setting mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st set lever 2 2nd set lever 4 Gear 6 Release lever 14 1st closing lever 15 2nd closing lever

Claims (1)

(57) [Scope of request for utility model registration] 1. A focal plane shutter comprising: a substrate having a shutter opening; an opening and closing blade group for opening and closing the shutter opening; and a drive mechanism for operating each of the blade groups. A first set lever that rotates when the set operation is performed, a gear mechanism that meshes with the first set lever and rotates, and a shaft that is coaxially supported with the first set lever and meshes with the gear to set the drive mechanism. A second set lever, wherein the rotation angle of the second set lever is larger than the rotation angle of the first set lever via the gear mechanism.