JPH0123133Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a film back that can be attached to and detached from a camera.

This type of film bag has a film supply chamber and a film take-up chamber formed on both sides of an opening corresponding to the back surface of the camera body, and allows the film bag to be replaced during use. a pressure plate that presses the film passed between the film supply chamber and the film take-up chamber toward the guide rail surface of the camera; and a light-shielding lid that shields the opening in order to make the film bag itself light-tight. ,
It is conceivable to have a mechanism that retracts the pressure plate and the film out of the operating trajectory of the light-shielding lid in conjunction with the operation of shielding the opening with the light-shielding lid. However, when this film back has a structure in which the pressure plate and the film are retracted in conjunction with the shielding operation of the light-shielding lid, the pressure plate and the film become a load on the light-shielding lid. As a result, the smoothness of the shielding operation is impaired and the light shielding lid is deformed.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks and to provide a film back in which an appropriate operational relationship is established between the operation of the pressure plate and the operation of the light-shielding lid.

An embodiment of the present invention will be described below with reference to the drawings.

The schematic partial sectional view of FIG. 1 shows an embodiment of the present invention mounted on a camera having a camera body 30, a lens 31, a grip 32, etc. In this embodiment, within the film bag body 1, a support rail 2a, on which the film F is mounted on the pressure plate 2,
2b and is integrally supported with the pressure plate 2.

As shown in FIG. 2, which is a perspective view of this embodiment in which only the mechanism for taking in and out the pressure plate 2 is shown, the pressure plate 2 is mounted on a pressure plate substrate 3 via an elastic member, and the pressure plate substrate 3 is attached to a pressure plate support substrate. It is mounted on the support substrate 4 by a mounting shaft 5 so as to be tiltable relative to the support substrate 4.

The support substrate 4 is rotatable around a rotation shaft 6 fixed to the film bag body 1, and is supported by a spring 7.
As a result, the lever portion 4a of the support substrate 4 is always in contact with the cam surface of the actuating cam 8. The operating cam 8 is moved by operating an operating knob 9 from the outside, and the possibility of this operation depends on the state of the light-shielding lid 10.

Here, with reference to FIG. 3, the configuration of the portion of this embodiment that is omitted in FIG. 2 will be described.

The rotating body 9a rotates together with the operating knob 9, and the operating knob coupling 11 fixed to the rotating body 9a and the operating cam coupling 12 fixed to the operating cam 8 are engaged with each other, so that the operating cam is rotated. 8 rotates together with the operating knob 9. In this way, the pressure plate 2 is moved in and out by the cam action between the cam surface and the lever portion 4a. In addition, in the drawing, for convenience of illustration,
Both coupling rings 11, 12 are shown separated.

The rotating body 9a has an engaging member, that is, a control pin 1.
3 is implanted, and the control members, namely the first control lever 14, the limit lever 15 and the second control lever 16, are connected to the respective rotation axes 17, 18, 19.
It is rotatably mounted on the top. Limit lever 15
and second control lever 16 are biased clockwise by springs 20 and 21, respectively. In this way, the restriction lever 15 is moved according to the state of the light-shielding lid 10,
Furthermore, the movement of the operating knob 9 is regulated via the first and second control levers 14 and 16 and the control pin 13.

The operation of this embodiment configured in this manner will be explained.

In the state shown in FIG. 3 with the light-shielding lid 10 still inserted, in an attempt to push the pressure plate support substrate 4, that is, the pressure plate 2 forward and make the film F face the camera aperture A (see FIG. 1), the operation knob 9 is pressed.
When the rotating body 9a is rotated clockwise, the rotating body 9a also rotates together. However, since the one end 15a of the limit lever 15 engages with the one end 10a of the light-shielding lid 10 and the lever 15 cannot be rotated and retreated in the clockwise direction, the protrusion of the second control lever 16 is also connected to the spring 21. The biasing force keeps the limit lever 15 in the illustrated state in contact with the end surface thereof. Therefore, the clockwise movement of the control pin 13 is controlled by the tip of the second control lever 16, and the clockwise rotation of the operating knob 9 is stopped after a certain amount of rotation. At this time, the lever portion 4a of the pressure plate support substrate 4
a, and the pressure plate 2 does not move forward.

Next, the case shown in FIG. 4, in which the light-shielding lid 10 is partially pulled down, will be described. At this time,
Since the other end 15b of the restriction lever 15 engages with the end surface 10b of the light-shielding lid 10 and its movement is restricted, the third
As in the state shown in the figure, the limit lever 15 is prevented from rotating clockwise. Therefore, as in FIG. 3, the clockwise rotation of the operating knob is limited to a certain range, and the pressure plate 2
cannot move forward.

Incidentally, when transitioning from the state shown in FIG. 3 to the state shown in FIG.
From the contact between one end 10a and the other end 15b and end surface 10b
This is carried over to the contact of the

FIG. 5 shows a state in which the light-shielding lid 10 is completely pulled down. In this state, the other end 15b of the restriction lever 15 can enter into the groove 10c of the light-shielding lid 10. Therefore, the limit lever 15 is rotated clockwise by the spring 20 to the state shown in the figure, and the second control lever 16 also follows and rotates the spring 20.
The lever 16 rotates clockwise with a biasing force of 1, and the tip of the lever 16 retreats to a range where it does not interfere with the clockwise movement of the control pin 13 of the rotating body 9a. Therefore, by operating the operation knob 9, the lever portion 4a of the pressure plate support substrate 4 is
It becomes possible to select and contact either the constant radius portion 8a of the actuating cam 8 or the concave portion 8b with a reduced radius. If the operating knob 9 is operated so that the lever portion 4a comes into contact with the portion 8a, the pressure plate 2
takes a retracted position out of the orbit of the light-shielding lid 10 (see FIG. 2), and if the light-shielding lid 10 is pushed up in this state, the film bag becomes light-tight. On the other hand, when the operating knob 9 is rotated clockwise, the lever portion 4a of the pressure plate support substrate 4, which is biased counterclockwise by the spring 7, moves along the cam surface of the operating cam 8 into the recessed portion 8b.
The substrate 4 rotates counterclockwise around the shaft 6 and pushes out the pressure plate 2. In this way, as shown in FIG. 1, the film F is opposed to the aperture A of the camera.

Conversely, even if an attempt is made to insert the light-shielding lid 10 in the state shown in FIG. be done. In this case, since the light shielding lid 10 cannot be pulled down any further at the same time, the other end 15b and the groove 10c also constitute a locking means for preventing the lid 10 from being completely removed from the film bag.

If you want to insert the light-shielding lid 10, turn the operating knob 9 counterclockwise, the control pin 13 pushes one end 14a of the first control lever 14, and the clockwise rotation of the lever 14 causes the restriction lever 15 to move counterclockwise. Just rotate it. As a result, the limit lever 15
The other end 15b is retracted from the groove 10c of the light-shielding lid 10, and the light-shielding lid 10 can be inserted.

In the first embodiment, the interlocking members include the rotating body 9a, the operating knob coupling 11, the operating cam coupling 12, the operating cam 8, the portion 8a, the recessed portion 8b, the lever portion 4a, the pressure plate substrate 4, and the pressure plate support substrate. 3 and a spring 7. Further, the control mechanism includes a limit lever 15 and a second control lever 1.
6. Consists of springs 20 and 21.

By the way, the control lever does not touch the end surface 8 when the light-shielding lid 10 is in either of the states shown in FIG. 3 or FIG.
It is also possible to have a portion that contacts only b.
An example of this is shown in FIG.
Has 3a.

In the second embodiment shown in FIG. 6, the interlocking mechanism is composed of the same members as in the first embodiment, but the control mechanism includes a limit lever 23, a second control lever 16, and a spring 20. and a spring 21.

Note that rotation of the operating knob 9 at both ends of its rotational movement is stopped by a method not shown, such as a click, thereby maintaining each lever in its respective state against the spring biasing force applied to each lever. It is something.

As detailed above, according to the present invention, the pressure plate is always retracted from the opening both when the light-shielding lid is retracted from the opening and when the light-shielding lid covers the opening, and the pressure plate is directed toward the opening. The light-shielding lid is always retracted from the opening both when it is projected and when it is retracted from the opening. Therefore, the light-shielding lid and the pressure plate are never positioned in the opening at the same time. As a result, there is no possibility that either one will be damaged due to contact between the two. Of course, in any of the above cases, since the two do not come into contact with each other, one does not interfere with the smooth operation of the other.

[Brief explanation of the drawing]

FIG. 1 is a schematic partial cross-sectional view showing an embodiment of the present invention attached to a camera; FIG. 2 is a perspective view of the embodiment of FIG. 1 showing only the mechanism for moving the pressure plate in and out; 3 to 5 are diagrams for explaining the operation of the embodiment of FIG. 1, and FIG. 6 is a diagram similar to FIG. 3 showing a modification of the embodiment of FIG. 1. Explanation of symbols of main parts, light-shielding lid...10, operating members...8, 9, pressure plate...2, regulating member...1
5, 16, 17.

Claims (1)

[Scope of Claim for Utility Model Registration] A film bag that is detachably attached to a camera, comprising: a light-shielding lid that is movable between a shielding position that covers an opening of the film bag and a retracted position that is retracted from the opening; a film support that is movable between a protruding position that is close to the aperture of the camera and located within the sliding track of the light-shielding lid, and a buried position that is buried within the film bag and retreated a predetermined distance from the sliding track of the light-shielding lid. a pressure plate; a manual operation knob that can be rotated in forward and reverse directions; a manual operation knob that is interlocked with the operation knob and moves the pressure plate from the buried position to the protrusion position by rotation of the operation knob in the forward direction; an interlocking mechanism for moving the pressure plate from the protruding position to the buried position by rotating the operation knob in the opposite direction; moving the light shielding lid from the retracted position to the shielding position within the movement locus of the light shielding lid in the retracted position; a first position where the operation knob is prevented from rotating in the forward direction, and a first position where the operation knob is retracted from the movement locus of the light-shielding lid to allow movement of the light-shielding lid between the retracted position and the shielding position; a control mechanism movable to a second position that prevents forward rotation of the knob; when engaged with the control mechanism and the light-shielding lid is in the retracted position, the control mechanism is moved by reverse rotation of the operating knob; a control member that is displaceable so as to move the control knob from a first position to a second position; and a control member that is provided in the interlocking mechanism and that is freely engageable with the control member in response to movement of the operation knob and that displaces the control member. and an engagement member that engages with the control mechanism to prevent the operating knob from rotating in the forward direction when the control mechanism is in the second position; A film bag characterized in that it is prevented from simultaneously moving into the opening.