JPS6322289B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rewind stop device for a camera that winds and rewinds a film using an electric motor.

In a camera that uses an electric motor to wind and rewind the film, when the electric motor is operated to rewind the film, it is generally started by switching an operating member to a rewind mode. Incidentally, in such a camera, conventionally, when rewinding the film is to be stopped, the operator has to switch the operating member to the winding mode again. That is, only while the operator holds the operating member in the rewind mode side, the electric motor operates to rewind the film, and when the operator releases the holding of the operating member, the operating member is in the rewind mode. It is configured to automatically return to the winding mode and stop driving the electric motor, or when the operator switches the operating member to the rewinding mode, the operating member is locked in that position and the rewinding operation is performed. The system is configured so that the operator can release the lock to stop rewinding. However, with such conventional configurations, for example, in the former case, the operator must always hold the operating member in the rewind mode side during the rewind operation, which has the disadvantage of causing pain in the fingers. In the latter case, the operator must release the lock to stop rewinding, so if the operator does not check the rewinding status of the film, the problem may occur after all the film has been rewound into the cartridge. However, they were driven by an electric motor, which had the drawbacks of draining the battery and overheating the camera. Furthermore, in such a rewinding device, it is necessary to reverse the film counter in conjunction with the rewinding operation of the film in order to inform the operator that rewinding has been completed, resulting in a complicated configuration. It was hot too.

By the way, in order to eliminate the drawbacks of such a rewinding device, in the rewinding mode, when the film comes off the spool and is rewound to the middle of the aperture, a detection member in contact with the end surface of the film is actuated, and an electric motor is activated. Device to stop power supply to (first
-3) are known. That is, this device is constructed as follows as shown in the figure. 101 is a cartridge for storing the film 102;
03 is a sprocket, and 104 is a spool.
Reference numeral 105 denotes a detection member which is slidable by being guided by a guide pin 108 and is biased by a spring 106 so that its end comes into contact with the film 102.
5 is configured to switch the switch 107. Therefore, when the film 102 is rewinded and the film 102 reaches the state shown in FIG. 2, the detection member 105 slides in the direction of the arrow to turn off the switch 107. Power supply to is stopped. Therefore, when the film 102 is rewound with a predetermined amount left in the cartridge 101, the electric motor 112 is stopped and the film rewinding operation is completed.
In FIG. 3, E is a power source, 110 is a switch that controls the power supply to the electric motor 112 during film winding, and 111 is a switch that controls the electric motor 1 when the back cover of the camera is open or when the film 112 is not loaded.
This is a switch to enable power supply to 12. However, such devices have the following drawbacks. That is, since the film surface is constantly pressed by the sensing member, the flatness of the film deteriorates, and since the sensing member and the film are in contact with each other during winding and unwinding of the film, the load increases. Ta. Furthermore, with this device, if there is only a switch for the detection member, it will not be possible to supply power to the motor when no film is loaded, so a switch that is turned on when the back cover is open is used instead of the switch mentioned above. The camera had to be installed in parallel with the camera, making the camera's electrical circuit complicated. Furthermore, a system in which the change in load at the end of film rewinding is detected and the drive of the electric motor is automatically stopped has been proposed in Japanese Patent Application Laid-Open No. 51-46121 and Publication of Utility Model Publication No. 56-30814. However, these require a new load change detection mechanism to detect the above-mentioned changes in load, or
A complicated and expensive helical gear had to be installed, which again caused problems in terms of structure and cost.

The present invention has been made to solve the above-mentioned drawbacks of conventional devices, and includes a motor, a planetary gear device in which a sun gear is driven by the driving force of the motor, and a planetary gear that meshes with the planetary gear of the planetary gear device. The film rewinding system is actuated by the driving force of the motor, and a predetermined meshing force is applied between the film rewinding system and the planetary gear until the film rewinding is completed due to the film load acting on the film rewinding system. a rewinding gear that maintains the meshing state with the planetary gear by generating a force, and a rewinding gear that biases the planetary gear in a direction to remove it from the rewinding gear with a biasing force that is weaker than the predetermined meshing force, and after the film is finished rewinding. A rewind stop device for a camera having an extremely simple structure and low cost, comprising a biasing means for disengaging the planetary gear from the rewinding gear to complete the film rewinding operation when the predetermined meshing force is lost. This is what we are trying to provide.

Hereinafter, the present invention will be explained in detail based on embodiments shown in the drawings.

FIG. 4 shows a drive circuit for the motor 1 in the embodiment of the present invention, and in this figure, E
2 is a power source, and 22 is a switch that is switched by a winding stop lever 21, which will be described later. FIG. 5 is a perspective view showing an embodiment of the present invention. In this figure, 1 is a motor serving as a drive source for winding and rewinding the film 53 as described above, 2 is a spool, and 3 is a motor that drives the spool 2. This is a gear wheel connected by friction. 4 is an output shaft of the motor 1, and a gear 5 that meshes with a gear 7 is fixed to the tip of the output shaft. This gear 7 is rotatably supported by a support shaft 8 installed in the camera body (not shown), and meshes with a gear 9 and a gear 28. 1
0 is a gear that rotates integrally with the gear 9, and the two-stage gear made up of the gears 9 and 10 is a spindle mounted on a swing lever 12 that is swingably supported on the spindle 8. 11 so as to be rotatable. Further, the swing lever 12 is biased clockwise by a spring 50. 17 is a gear that meshes with gear 10,
It is fixed to a rotating shaft 16 to which a gear 13 is fixed at one end. Gear 13 meshes with gear 3 and gear 14, and rotates spool 2 via gear 3 and sprocket 15 via gear 14 in the same direction. Reference numeral 19 denotes a known one-way clutch, which transmits the rotational force to the rotation shaft 20 only when the rotation shaft 16 rotates clockwise.
24 is a charge cam, and 27 is a winding cam, both of which rotate integrally with the rotation shaft 20. Reference numeral 25 denotes a charge lever that swings around a support shaft 25 by a charge cam 24, and is biased clockwise by a spring 49, and is pushed against the protrusion 4 of the running plate 46.
6a and one side 25a thereof are engaged with each other. This traveling plate 46 starts traveling when the camera is released and controls an automatic focus adjustment mechanism and a shutter mechanism (not shown), and when it is moved by the charge lever 25 against the biasing force of a spring 47. , the automatic focus adjustment mechanism and the shutter mechanism are brought into a ready state for photographing.

Next, reference numeral 21 denotes a wind stop lever that is swingably supported by the support shaft 18 and is biased counterclockwise by a spring 23. Projection 21a that engages with notch 27a
A protrusion 21b for switching ON/OFF of the switch 22 described above is formed. Further, this wind stop lever 21 has one side 21c connected to the running plate 4.
When the travel plate 46 completes travel, the end portion 46b of the travel plate 46 comes into contact with the end portion 46b of the travel plate 46, and is rotated clockwise. 32 is gear 28
is a swinging lever that is swingably supported by a support shaft 29 that rotatably supports the gear 28 and is biased counterclockwise by a spring 52. It is rotatably supported. 33 is a gear that meshes with gear 30 when the camera is set to rewind mode, and gears 34, 3
5 and 36, a fork 37 is driven which engages with the winding shaft of a cartridge (not shown). 38 is an actuation plate, and this actuation plate 38 is connected to the support shaft 39 through a groove 38a.
It is slidably supported by a spring 51 and biased toward the left in the drawing. Further, the actuation plate 38 is formed with a protrusion 38b that engages with the end 12a of the swing lever 12.
A protrusion 38c that engages with the end 32a of the gear 9 and the gear 30 is formed by the movement of the protrusion 38c.
The rotational position of the shaft is changed. 4
Reference numeral 3 denotes a rewinding operation plate, and its groove 43a is fitted with a support shaft 44 so that it can be slid in the direction of arrow c by an operation knob 45, and its end 43c is connected to the side surface 21c of the rewinding lever 21. It is configured so that it can be engaged with. In addition, in this operation plate 43, 43c is a protrusion for fixing the operation knob 45. Further, 39 is a transmission lever for transmitting the operation of the operation plate 43 to the operation plate 38, and this transmission lever is rotatably supported on the support shaft 40, and the groove 39a thereof is embedded in the operation plate 38. The groove 39b is fitted with a pin 42 implanted in the operation plate 43. Therefore, the actuating plate 38
The movement will be performed in a direction different from the movement direction of the operation plate 43.

Next, the operation of the embodiment configured as described above will be explained, but first, the winding operation will be explained.

FIG. 5 shows a state in which the winding is completed, and when the release button (not shown) is operated from this state to start the travel of the traveling plate 46, the automatic focus adjustment mechanism and shutter mechanism (not shown) are activated by the traveling plate 46. The shooting operation of the camera ends. After that, the end portion 46b of the traveling plate 46 engages with the side surface of the wind stop lever 21, and the wind stop lever 21 is moved by the spring 4.
It is rotated clockwise by the urging force of 7. As a result, the protrusion 21a of the wind stop lever 21 and the wind stop cam 2
7 is disengaged from the notch 27a, and the gear 1
7 becomes rotatable in the direction of the arrow, and the protrusion 21
Since the switch 22 is turned to the ON side by the switch b, the motor 1 starts driving. At this time, since the gear 17 and the gear 10 are meshed, the driving force of the motor 1 is transmitted to the gear 17 via the gears 5, 7, 9, and 10, and the gear 17 rotates in the direction of the arrow. For this reason, the gear 13
Since the film 53 also rotates in the direction of the arrow, the spool 2 and sprocket 15 also rotate in the direction to wind up the film 53. Further, the rotation of the gear 17 in the direction of the arrow is transmitted to the rotation shaft 20 via the one-way clutch 19, and the charge cam 24 and the stop cam 27
Rotate. As a result, the charge lever 25 is actuated against the biasing force of the spring 49, and the running plate 46
By returning the camera to its initial position, the automatic focus adjustment mechanism and the shutter mechanism are again ready for photographing. By the way, due to the return movement of the running plate 46, the end portion 46b of the running plate 46 and the winding lever 2
1 is released, but at this time, the notch 27a of the wind stop cam 27 has rotated to a position where it does not engage with the protrusion 21a of the wind stop lever 21, so the wind stop lever is held at a position where the protrusion 21b turns on the switch 22. Therefore, in the motor 1, after the traveling plate 46 is returned to the initial position, the winding stop cam 27 rotates once and the notch 27
When the protrusion 21a of the winding lever 21 re-engages with the winding lever 21, the winding is stopped. Furthermore, since the sprocket 15 is designed to feed the film 53 one frame when the stop cam 27 rotates once, the preparation for photographing the film 53 is completed at this time.

Note that by winding the film 53, the fork 3
7 also rotates in the direction of the arrow, but at this time gear 30
Since the gears 33 and 33 are not in mesh with each other, there is no problem in the winding operation.

Next, the rewinding operation will be explained. When the operating knob 45 is moved in the direction of arrow c from the state shown in FIG. 5 to bring the operating plate 43 into the state shown in FIG. The lever 21 is held by its protrusion 21b at a position where the switch 22 is turned on. As a result, the motor 1 is brought into a driving state. On the other hand, the movement of the operating plate 43 is also transmitted to the operating plate 38 via the transmission lever 40, so the operating plate 38 moves to the right in the figure against the biasing force of the spring 51, and the swinging lever 12 and 32 are rotated counterclockwise around their respective support shafts 8 and 29. At this time, the swing lever 12 moves the gear 17 and the gear 10 while resisting the biasing force of the spring 50.
is rotated until the mesh is released, and
The swing lever 32 is rotated to a position where the gear 30 is engaged with the gear 32 while being influenced by the biasing force of the spring 52. Therefore, the motor 1 is driven by the gears 5, 7, 28, 30, 33, 34, 35, 36.
The signal is transmitted to the fork 37 via the fork 37, and drives a winding shaft in a cartridge (not shown) to rewind the film 53. During this period, the spool 2 and sprocket 15 rotate in the direction of the arrow, causing the rotation shaft 16 to rotate clockwise, but the rotation is not transmitted to the rotation shaft 20 by the one-way clutch 19. Therefore, the charge cam 24 and the stop cam 27 are not operated, and the running plate 46 is not charged.

By the way, during the rewinding operation of the film 53, the biasing forces of the springs 50 and 51 act on the swing lever 32 via the actuating plate 38 in the direction of releasing the engagement between the gears 30 and 33. Since the resultant force of the meshing force of the gears 30 and 33 and the biasing force of the spring 52 is greater than the resultant force of the biasing forces of the springs 50 and 51, the gears 30 and 33 are held together until the rewinding is completed. Maintain the engaged state. This state will be explained in detail below with reference to FIG. In this figure, 28' is the base circle of the gear 28, 30' is the base circle of the gear 30, and 33' is the base circle of the gear 33, and the rotation direction of each gear is IJK. Also, the motor 1 is attached to the gear 28.
As described above, the driving force is transmitted to the gear 30, and the gear 30 is supported by the rocking lever 32 to make planetary motion around the gear 28. By the way, since the rotational direction of the gear 28 is I, an acting force is generated on the gear 30 in the meshing direction L of the gear 28 and the gear 30. This is shown as R in gear 30. Also, here is Folk 37
Considering the force for winding the film 53, since the film 53 is wound around the spool 2, there are various factors such as the fit between the spool 2 and the camera body, the meshing of the gear 3 and the gear 13, the frictional force of the sprocket 15, and the force on the film 53. It can be seen that a large load is applied to the fork 37 due to the frictional force between the fork 37 and the camera body. On the other hand, since the gear 33 is driven by the gear 30, the load on the fork 37 is due to the gear 33.
acts in the direction of stopping rotation of the gear 30. Therefore, a force acting in the zero direction is generated on the gear 30 as a reaction force of the load. This is Q at the gear 30.
Shown as And this acting force Q is fork 3
7 increases according to the load applied to it. Therefore, while the film 53 is being rewound, an acting force S, which is a composite force of the acting forces R and Q, acts on the rotation center Y of the gear 30. Therefore, this acting force S and the spring 5
Of the resultant force of the urging forces of spring 50 and spring 51, the component force that attempts to rotate the swinging lever 32 counterclockwise is the component force that rotates the swinging lever 32 clockwise of the resultant force of the urging forces of the spring 50 and the spring 51. If the force is set to be greater than the desired component force, the meshing state of the gears 30 and 33 will be maintained while the film 53 is being rewound.

Furthermore, when the film 53 is removed from the spool 2, the load acting on the fork 37 becomes extremely small, and the acting force Q also becomes extremely small, so the swinging lever 32 is rotated clockwise by the combined force of the springs 50 and 51. As a result, the meshing between the gears 30 and 33 is released. In addition, when using this mechanism, it is necessary to consider the arrangement of gears 28, 30, and 33, and unless the angle θ formed by the rotation center XYZ of each gear is a considerably obtuse angle, the acting force S will be
If θ=180°, the gear 30 will rotate around the gear 28 like a planetary gear and cannot maintain engagement with the gear 33. In this example, this angle θ
is approximately 150°, but this angle θ is from 120° to
It has been confirmed that meshing between the gears 30 and 33 can be maintained without any problem if the angle is between 170 degrees.

By the way, when the film 53 comes off the spool 2 and the load on the fork 37 decreases, the actuating plate 3
8 is moved to the left in the figure by the biasing force of the spring 51 from the state shown in FIG. Therefore, the operating plate 43 moves rightward in the figure via the transmission lever 40, so that the end portion 43c of the operating plate 43 no longer presses the winding lever 21, and the protrusion 21a pushes the winding lever 21 toward the winding cam 27. Rotate it to a position where it engages with the notch 27a. As a result, switch 22 is turned OFF.
Then, the power supply to the motor 1 is stopped, and the rewinding operation is completed. At this time, the swing levers 12 and 32 also rotate clockwise in FIG. 6, so that the gears 30 and 33 are disengaged, and the gears 17 and 10 are brought into engagement again.

Furthermore, if the notch 27a of the wind stop cam 27 is in a position where it does not engage with the protrusion 21a of the wind stop lever 21, the switch 22 remains in the ON state even after the operation plate 43 moves to the right in the figure. Retained. Therefore, even after the film 53 has been rewinded, the motor 1
is driven, rotates the winding stop cam 27 via the gears 10 and 17, and is stopped when the notch 27a engages with the protrusion a of the winding lever 21.

In this embodiment, a winding method is used in which the film 53 is fed into the spool 2 by the sprocket 15, but in the present invention, the film 53 is fed into the spool 2 by the sprocket
Of course, the sprocket 15 can also be applied to a so-called spool drive camera in which the sprocket 15 is used exclusively for indexing and charging the film 53.

As explained above, according to the present invention, the motor and
a planetary gear device in which a sun gear is driven by the driving force of the motor; and a planetary gear device that meshes with the planetary gear of the planetary gear device to operate a film rewinding system by the driving force of the motor, and the film rewinding system. a rewinding gear that maintains a state of meshing with the planetary gear by generating a predetermined meshing force between the film and the planetary gear until the film rewinding is completed due to the film load acting on the film; The planetary gear is urged in a direction to be removed from the rewinding gear with an urging force that is weaker than the rewinding force, and when the predetermined meshing force disappears after rewinding the film, the planetary gear is removed from the rewinding gear and the film is removed. Since the camera rewind stop device is equipped with a biasing means for ending the rewind operation, it is possible to provide a camera rewind stop device with a simple configuration and low cost, and its usefulness is extremely high. It is.

[Brief explanation of the drawing]

1 and 2 are perspective views showing a conventional automatic rewinding stop device, FIG. 3 is a circuit diagram showing a motor drive circuit of the device shown in FIGS. 1 and 2, and FIG. 4 is an embodiment of the present invention. FIGS. 5 and 6 are perspective views showing one embodiment of the present invention, and FIG. 7 is for explaining the meshing state of gears in the embodiment shown in FIGS. 5 and 6. Top view. 1... Motor, 2... Spool, 21... Winding stop lever, 22... Switch, 24... Charge cam, 27... Winding stopping cam, 30... Gear, 32
... Swinging lever, 33 ... Gear, 37 ... Fork, 38 ... Operating plate, 43 ... Operation plate, 53 ...
film.

Claims (1)

[Claims] 1. A motor, a planetary gear device in which a sun gear is driven by the driving force of the motor, and a planetary gear of the planetary gear device meshes with the planetary gear so that the driving force of the motor operates a film rewinding system. a rewinding gear that generates a predetermined meshing force with the planetary gear and maintains the meshing state with the planetary gear until the film is finished rewinding due to the film load acting on the film rewinding system; The planetary gear is urged in a direction to be removed from the rewinding gear by a biasing force weaker than the predetermined meshing force, and when the predetermined meshing force disappears after film rewinding is completed, the planetary gear is removed from the rewinding gear. 1. A rewind stop device for a camera, comprising: urging means for removing the film from the film rewinding device to terminate the film rewinding operation.