JPH0588806B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to an improvement in a camera back cover locking device having a safety feature that prevents the lock from being released when film is loaded.

"Prior art and its problems" Conventional back cover locking devices of this type include a film amount detection mechanism in the camera body, which detects the amount of film wound around the take-up spool, and A device that operates a locking means on the back cover to lock the back cover when the amount of water applied exceeds a predetermined amount, and releases the back cover lock when the amount falls below a predetermined amount, allowing the back cover to open. A device is known in which the back cover is unlocked only when the completion of rewinding of the film is detected by a film end detection mechanism.

However, all of the above-mentioned back cover unlocking devices require respective detection mechanisms and a mechanism for transmitting the detection results to the locking member of the back cover, resulting in a complicated structure. In addition, if an emergency situation such as film damage occurs while winding or rewinding the film, the amount of film wrapped around the take-up spool will not become less than a predetermined amount, making it impossible to detect the amount of film, or detecting the end of the film. There was a fear that the camera back could no longer be unlocked and the camera back could not be opened.

In order to solve this problem, a device is already known in which the film rewinding operation and the back cover unlocking operation are linked. In this device, if the film is damaged during winding, the back cover is opened by the following means. That is, the rewinding shaft is rotated once in the rewinding direction, then pulled out and moved in the axial direction, and while maintaining this state, the rewinding shaft is rotated in the rewinding direction. However, this operation is too complicated for the user, and since the rewinding shaft is moved in the axial direction, the frictional interlocking member attached to the rewinding shaft is easily damaged.

``Object of the Invention'' The present invention uses a simpler mechanism to ensure that the back cover is locked when loading the film, and in the event of an emergency such as film damage, the back cover can be unlocked by a simple manual operation. Moreover, the object of the present invention is to provide a back cover locking device that does not require a film winding amount detection mechanism or a film end detection mechanism.

``Summary of the Invention'' The present invention provides a lock control member that moves linearly between the winding end and the rewind end in conjunction with the winding and rewinding operations of the rewind shaft, and the direction of movement of the lock control member is When the movement direction of the back cover locking member, which is biased in the direction of locking the back cover, is substantially perpendicular to the moving direction, and the lock control member is located at the upper end of the winding, it engages with the back cover locking member to release the lock. A locking part that prevents the film from moving in the direction, and a push operation part that can be operated from the outside of the camera body to manually move the lock control member located at the winding end to the winding end. It is characterized by

"Embodiments of the Invention" Examples of the present invention will be described in detail below with reference to the drawings.

A film chamber 12 is formed in the camera body 11 (FIG. 3), and a pair of forks 13 that engage with a film winding shaft of a cartridge (not shown) are provided in the body 11 above the film chamber 12. , are arranged facing the film chamber 12. This fork 13 has a metal 17 located on the main plate 16.
A film rewinding shaft 14 is fitted and fixed with a set screw 15 on both sides of the fork 13, and a metal 17 serves as a bearing so that it can freely rotate together with the fork 13.

A driven gear 18 is integrally formed coaxially with the outer periphery of the film rewinding shaft 14.
meshes with a drive gear 20 rotatably supported by a gear shaft 19 fixed on the main plate 16. Therefore, when rotation is applied to the drive gear 20 by the drive of a motor (not shown), the rotational force is transmitted to the film rewinding shaft 14 via the drive gear 20 and the passive gear 18, and the rotational force is transmitted to the film rewinding shaft 14 in the winding or rewinding direction. The film rewinding shaft 14 rotates.

A friction spring 21 that frictionally engages with the film rewinding shaft 14 is fitted into the small diameter portion of the upper end of the film rewinding shaft 14.
Both ends of the unwinding shaft 14 form a pair of parallel operating arms 21a and 21b extending substantially in the radial direction. The friction spring 21 swings in the same direction as the rotation of the film rewinding shaft 14 due to frictional force.

A slideable lock control member 22 is provided in the main body 11 near the film rewinding shaft 14.
1 along the left and right direction. Long holes 23 and 24 are formed in this lock control member 22,
Guide pins 25 and 26 fixed on the main plate 16 are inserted into each. This allows the lock control member 22 to slide in the left and right directions within the effective lengths of the elongated holes 23 and 24.

An actuating pin 27 is installed in the center of the lock control member 22, and the actuating pin 27 is connected to the actuating arms 21a, 21b of the friction spring 21.
It is held between. Therefore, when the film rewinding shaft 14 rotates in either the winding direction or the rewinding direction, the friction spring 21 rotates in the same direction, and the operating pin held between the operating arms 21a and 21b rotates. 27, that is, the lock control member 22 moves to the left or right. That is, it moves linearly between the winding up end and the unwinding end which are regulated by both ends of the elongated holes 23 and 24.

A rotating shaft 28 is fixed on the main plate 16 at a position close to the lock control member 22, and a back cover interlocking lever 29 is rotatably attached to the rotating shaft 28. The back cover interlocking lever 29 has a locking portion 2 formed at one end thereof at the right end of the lock control member 22 in the figure.
2a, and has a locking claw 30 that engages with the back cover 3 at the other end.
It has a pressing part 33 that comes into contact with a pressing protrusion 32 protruding from the inner surface of 1, and is biased by a spring 34 in a direction in which the locking pawl 30 engages with the locking part 22a. When the back cover 31 is closed (see FIGS. 2 and 4), the pressing portion 33 is pressed against the pressing protrusion 3.
2, the locking pawl 30 is not locked to the locking portion 22a, and when the back cover 31 is open (see FIG. 5), the locking pawl 30 locks the locking portion 22a. It's becoming like that.

A back cover lock member 35 is slidably disposed on the outer surface of one side wall 11a of the main body 11 along the vertical direction of this side wall 11a. In other words, as shown in FIG.
The elongated holes 36 and 37 are guided through the holes 39, respectively. Therefore, the back cover locking member 35 can slide vertically within the effective length of the long holes 36 and 37. This sliding direction is perpendicular to the lock control member 22.

The back cover locking member 35 is formed with an upright portion 40, and this upright portion 40 has a compression spring 4 accommodated and held in a spring holding groove 42 formed in the side wall 11a.
One end of the back cover locking member 35 is urged upward, that is, in the direction of locking the back cover. An operating member 43 is attached to the back cover locking member 35 by inserting its leg portion 43a into a mounting hole 44. The outside of the back cover locking member 35 and the operating member 43 are covered with a locking member cover 45.
This cover 45 is fixed to the protruding guide portions 38 and 39 with set screws 46 and 47.

At the center of the back cover lock member 35, the back cover 3
A key spatula 48 is formed to protrude from the side end of the key 1 and engages with a key spatula 49 to lock the lock. Further, a tip key portion 50 is formed at the upper end of the back cover locking member 35, and this tip key portion 50 is connected to a locking protrusion 22c formed protruding near the left end of the lock control member 22 in the figure. Engageable. That is, this locking protrusion 22c engages the tip key portion 50 when the lock control member is moving to the winding end.
The locking member 35 is engaged with the locking member 35 to prevent the back cover locking member 35 from moving to the unlocked position.

The left end of the lock control member 22 in the figure is a tapered press hole 5 formed in the camera body 11.
1, and serves as a pressing operation portion 22b protruding into the inside of the
When this pressing operation portion 22b is pressed, the lock control member 22 located at the winding end can be moved to the winding end. This press hole 51 can be made large enough, for example, that only a thin operating rod can fit therein, and not a finger.

Next, the operation of the apparatus of the present invention configured as described above will be explained.

A cartridge is loaded in the film chamber 12 with its film winding shaft engaged with a fork 13, and the leading end of the film is wound around the winding spool of the film winding shaft (not shown) so that it can be wound. It has become a state. The back cover 31 is closed,
A key spatula 49 is engaged with a key spatula 48 of the back cover locking member 35, which is biased to the lock position. At this time, the pressing protrusion 32 of the back cover 31
As shown in the figure, the pressing part 3 of the back cover interlocking lever 29
3 is pressed in the counterclockwise direction around the rotation shaft 28 against the biasing force of the spring 34, so that the locking pawl 30 of the back cover interlocking lever 29 engages the lock control member 22.
The lock control member 22 is guided by the guide pins 25 and 26 and can slide in the A direction.

When the motor is driven in the film winding direction in this state, the film rewinding shaft 14 is rotated counterclockwise in the figure via the drive gear 20 and the driven gear 18. Then, as shown in FIG. 2, the friction spring 21 frictionally engaged with the film rewinding shaft 14 swings in the same direction due to the frictional force, and the actuating arms 21a and 21b move through the actuating pin 27. to move the lock control member 22 in the A direction and open the elongated hole 2.
Slide it to the end of 3 and 24. This stop position of the lock control member 22 is the stop position of the winding end. At this time, the locking protrusion 22 of the lock control member 22
c fits under the tip key portion 50 of the back cover locking member 35, and the tip key portion 50 is locked by the locking protrusion 22c, so that the downward sliding movement of the back cover locking member 35 is prevented. Ru. In other words, the back cover 31
cannot be unlocked.

Even if the film continues to be wound up after this, the friction spring 21 is only frictionally engaged with the film rewinding shaft 14, so the lock control member 22
After reaching the winding end, only the film rewinding shaft 14 rotates, and the film is wound up by the film winding upper end.

If an emergency situation such as film damage occurs during film winding and you wish to open the back cover 31, manually press the pressing operation portion 22b of the lock control member 22 through the pressing hole 51 of the locking member cover 45. Bye. As a result, the lock control member 22 slides in the direction B, so that the locking protrusion 22c is released from the locking protrusion 22c by the tip key portion 50, and the back cover locking member 35 can be slid downward. Therefore, when the back cover locking member 35 is pushed down by the operation member 43, the key spatula parts 48 and 49 are disengaged and the back cover 31 is unlocked, making it possible to remove the film. can.

When rewinding the film, the motor rotates in reverse, and the film rewinding shaft 14 is rotated clockwise in the figure via the drive gear 20 and the driven gear 18. As a result, as shown in FIG. 4, the friction spring 21 that is frictionally engaged with the film rewinding shaft 14 rotates in the same direction due to its frictional force, and the actuating arms 21a and 21b are moved through the actuating pin 27. to move the lock control member 22 to the end of the movement in the B direction. That is, the lock control member 22 moves to the unwinding end. Since this state is the same as when the lock control member 22 is manually pressed, the lock of the tip key portion 50 that has been locked with the locking protrusion 22c is released, and the lock of the back cover lock member 35 is released. It becomes possible to slide downward. After winding is completed,
Manually operate the operating member 43 to open the back cover 31,
You can take out the film.

When the back cover 31 is opened, the back cover interlocking lever 29, which had been in elastic contact with the pressing protrusion 32 of the back cover 31 via the pressing part 33, is moved by the spring 34, as shown in FIG.
The urging force causes the locking claw 30 to rotate around the rotation shaft 28 in the clockwise direction in the figure, and the locking control member 2
2, and the lock control member 2
2 is prevented from moving in the A direction. Therefore, in this state, even if the film rewind shaft 14 is rotated in the film winding direction, the lock control member 22 will not move in the A direction. When the back cover 31 is closed, the pressing protrusion 32 presses the pressing part 33, so that the back cover interlocking lever 29 rotates around the rotation shaft 28 against the biasing force of the spring 34. The locking portion 22a by the locking claw 30
The lock is released.

``Effects of the Invention'' As described above, according to the present invention, the lock control member can lock the back cover locking member to lock the back cover only when winding the film. This lock control member can be manually moved to a position where it does not engage with the back cover lock member, so even if an emergency such as film damage occurs during normal use, this lock control member By manually operating the back cover, the locked state of the back cover by the back cover locking member can be released. Furthermore, since the back cover can be locked and unlocked mechanically, it is possible to eliminate the need for a conventional detection mechanism for detecting the amount of film winding and film end, as well as a mechanism for transmitting the detection results. .

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a camera back lock opening/closing device according to the present invention, FIG. 2 is a plan view of the device according to the present invention in a film winding state, FIG. 3 is a longitudinal sectional view of the device according to the present invention, and FIG. 5 is a plan view of the apparatus of the present invention when the film is being rewound, and FIG. 5 is a plan view of the apparatus of the present invention when the back cover is open. DESCRIPTION OF SYMBOLS 14... Film rewinding shaft, 21... Friction spring, 22... Lock control member, 22b... Press operation part, 22c... Locking protrusion (locking part), 29...
Back cover interlocking lever, 30...locking claw, 31...back cover, 3
5...Back cover lock member, 43...Operation member, 50...Tip key part.

Claims (1)

[Claims] 1. A lock control member that frictionally engages with the film rewinding shaft of the camera body and moves linearly between the winding upper end and the rewinding end in different directions according to the winding/rewinding rotation of the film rewinding shaft; a back cover locking member that is slidable in a direction substantially perpendicular to the control member and biased in a direction to lock the back cover; when the lock control member is located at the upper end of the winding, the back cover locking member engages with the back cover locking member; a locking part that prevents the lock control member from moving in the unlocking direction; and a locking part that can be operated from the outside of the camera body to manually move the lock control member located at the winding end to the winding end. A camera back cover locking device comprising: a press operation section;