JPS6139407Y2 - - Google Patents

Description

[Detailed description of the invention] In this invention, when the winding operation is performed with the camera back closed, the single tooth gear rotates once and the film counter gear is advanced by one frame, and when the camera back is opened, the single tooth gear rotates. The present invention relates to a camera film counter device that is retracted from a film counter gear.

Conventional devices of this type have many parts,
It has disadvantages such as complicated manufacturing and high manufacturing cost.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a film counter device which eliminates the above-mentioned drawbacks, has a small number of parts, is easy to manufacture, and is inexpensive to manufacture.

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 5 show one embodiment of the present invention, in which FIG. 1 is a schematic perspective view, FIG. 2 is a front view showing the back cover closed state, FIG. 3 is a side sectional view thereof, and FIG. The figure is a front view showing the camera back in an open state, and FIG. 5 is a side sectional view thereof.

The back cover 1 has one end rotatably supported by a camera body (not shown) in the right direction in FIG. An opening 2a is provided in the rear wall 2 of the camera body,
The protrusion 1a of the back cover 1 can enter into this opening 2a. The support member 3 is rotatably supported by a pin 4 on a portion 5 of the camera body. Support member 3
The falling portion 3a formed at the opening 2a faces the protrusion 1a of the back cover, and constitutes a detection member for detecting whether the back cover 1 is opened or closed. The rising part 3b formed on the support member 3 has its tip 3b' in contact with the inner surface 2b of the rear wall 2, and is made of a material having spring properties together with the support member 3 and the falling part 3a. . Therefore, the rising portion 3b urges the support member 3 to rotate counterclockwise in FIG. 1 by its own deflection. This rising part 3
b constitutes a first biasing member that biases the support member 3. As clearly shown in the figure, the one-tooth gear 6, which is a cylindrical member with a portion 6a cut out, has one end 6b loosely supported by the support member 3. Therefore, this gear 6 can rotate in the circumferential direction A of the gear 6 itself, and the gear 6 itself can rotate around the one end 6b as the rotation center.
It is possible to swing in the direction. The drive gear 6c is provided integrally with the one-tooth gear 6, and rotates by the winding operation regardless of the swing of the one-tooth gear 6 in the B direction. The bent portion 3c formed on the support member 3, together with the support member 3, the falling portion 3a, and the rising portion 3b, is made of a material having spring properties, and presses and urges the one-tooth gear 6 by its own deflection. This bent portion 3c constitutes a second biasing member that biases the one-tooth gear 6. The film counter gear 7 is rotatably supported by a portion 8 of the camera body, and is always urged counterclockwise in FIG. 1 by a zero return spring (not shown). The frame number display board 7a is provided integrally with the film counter gear 7. The one-tooth gear 6 makes one rotation counterclockwise in FIG. 1 via the gear 6c by one-frame winding operation, and the film counter gear 7 meshed with the one-tooth gear 6 thereby rotates by one tooth. 9 is an index that displays the number of pieces, and 7b is a stopper provided integrally with the gear 7.

As mentioned above, the device of the present invention includes the support member 3, the detection member 3a, the first biasing member 3b, and the second biasing member 3.
c is integrally constructed of a single plate having spring properties.

Next, the operation of this device will be explained. In the state shown in FIGS. 1 to 3 with the back cover 1 closed, the bent portion 3c presses the single tooth gear 6 against the film counter gear 7. When a hoisting operation is performed from this state, the one-tooth gear 6 rotates in the counterclockwise direction A in FIGS. 1 and 2. When the notch 6a escapes from above the counter gear 7, the counter gear 7 rotates slightly in the clockwise direction C against the biasing force of a zero return spring (not shown). At the same time, the circumferential portion of the one-tooth gear 6 enters between the teeth 7c and 7d of the film counter gear 7. At this time, the one-tooth gear 6 is slightly pushed out counterclockwise in FIG. 3 with one end 6b as the center, but the one-tooth gear 6 itself is retracted from above the counter gear 7 due to the biasing force of the bent portion 3c. There isn't. Therefore, the notch 6a is the first
Even if it escapes from above the counter gear 7 due to rotation in the counterclockwise direction A in FIGS. 2 and 2, the counter gear 7 will not rotate counterclockwise due to a zero return spring (not shown). Further, the circumferential portion of the single tooth gear 6 has teeth 7c and 7.
d, the counter gear 7 is not moved by the rotation of the gear 6. When the winding operation is continued further, the notch 6a reaches the next tooth 7d and the notch 6a meshes with the tooth 7d. When the winding operation for one frame of film is completed, the one-tooth gear 6
After completing one rotation, the film counter gear 7 is advanced by one tooth against a zero return spring (not shown). In this way, the state shown in FIGS. 1 to 3 is restored. However, at this time, the teeth of the counter gear 7 that mesh with the notch 6a are 7c to 7d.
In this way, the film counter gear 7 is advanced by one tooth by the winding operation for one frame of film. The frame number display board 7a also rotates in the clockwise direction C together with the counter gear 7, and the frame number display character 7e facing the index 9 also advances by one frame in response to the winding operation of one frame, and by repeating this operation, the image is taken. inform the person of the number of frames taken.

Next, the operation when opening the back cover 1 after a prescribed number of frames have been photographed will be explained. The state shown in Figures 1 to 3 (however, the film counter gear 7 rotates clockwise in Figures 1 and 2, and the frame number display characters "20", "24", "36", etc. are facing the index 9). When the back cover 1 is released from the lock position, the back cover 1 rotates about a rotation axis (not shown) in the right direction in FIG. When the protrusion 1a retreats from above the falling portion 3a as shown in FIGS. 4 and 5, the biasing force accumulated due to the deflection of the rising portion 3b itself causes the supporting member to
rotates counterclockwise from the state shown in FIGS. 1 and 2. This rotation of the support member 3 causes the one-tooth gear 6 to retreat from the film counter gear 7. At times, the one-tooth gear 6 swings toward the gear 7 about the end 6b due to the biasing force of the curved portion 3c, but the one-tooth gear 6 and the counter gear 7 do not mesh with each other. When the one-tooth gear 6 is retracted from the counter gear 7 in this way, the counter gear 7 is rotated counterclockwise in FIGS. 1 and 2 by a zero return spring (not shown).
The stopper 7b comes into contact with the single gear 6 and stops. In this state, the frame number display character 7e "S" faces the index 9 as shown in FIG. In this way, the frame number display is reset to zero.

Next, the operation when loading unexposed film and closing the back cover 1 will be explained. When the back cover 1 is closed from the state shown in FIGS. 4 and 5, the protrusion 1a is
Press a to rotate the support member 3 clockwise in FIG. At this time, since the end portion 3b' of the rising portion 3b is in contact with the inner surface 2b of the camera body, the rising portion 3b is deflected and accumulates an urging force for rotating the support member 3 in the counterclockwise direction. This clockwise rotation of the support member 3 causes the one-tooth gear 6 to mesh with the counter gear 7. At that time, the single tooth gear 6 swings counterclockwise in FIG. Accumulate the strength to do so. In this way, the state shown in FIG. 1 is reproduced.

In the description of the embodiment, a case has been described in which the hoisting operation is started from a state in which the notch 6a of the single tooth gear meshes with the tooth 7c of the counter gear (see Fig. 2), but the circumferential portion of the single tooth gear Even if the initial state is set so that the winding operation is started from the state where the film is inserted between the teeth 7c and 7d of the counter gear, the film counter gear 7 will advance by one tooth in one film winding operation. Not even.

As detailed above, according to the present invention, the support member, the detection member, the first biasing member, and the second biasing member are integrally formed of a single plate having spring properties, so the number of parts is reduced. A film counter device that is easy to manufacture and inexpensive to manufacture can be obtained.

[Brief explanation of the drawing]

1 to 5 show an embodiment of the present invention,
Fig. 1 is a schematic perspective view, Fig. 2 is a front view showing the back cover in the closed state, Fig. 3 is a side sectional view thereof, Fig. 4 is a front view showing the back cover in the open state, and Fig. 5 is the side thereof. FIG. Explanation of symbols of main parts, 3...Supporting member, 6...
...Single tooth gear, 4...A pin that rotatably supports the support member 3 on a part 5 of the camera body, 3a...A falling portion formed on the support member 3...A detection member that detects opening and closing of the back cover 1 , 1a...Protrusion on the back cover, 3b...Rising portion formed on the support member 3...First biasing member,
3c...Bending portion formed on the support member 3...Second biasing member.

Claims (1)

[Scope of utility model registration request] When the back cover is closed, the one-tooth gear meshes with the film counter gear, and when the winding operation is performed in this state, the one-tooth gear rotates once and advances the film counter gear by one frame. When the back cover is opened, the one-tooth gear meshes with the film counter gear. In a film counter device for a camera in which a one-tooth gear is retracted from the film counter gear, a support member that loosely supports one end of the one-tooth gear is provided, the support member is rotatably supported on the camera body, and the back cover is rotatably supported. a detection member that detects opening/closing of the film counter gear; a first biasing member that biases the support member so that the one-tooth gear retracts from the film counter gear when the back cover is retracted from above the detection member; a second biasing member that biases the one-tooth gear so that the one-tooth gear meshes with the film counter gear when the camera back presses the detection member against the force of the first biasing member; A film counter device characterized in that each of the film counter devices is formed integrally with the support member and made of a single plate having spring properties.