JPH0374369B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a film feeding device for an automatic loading camera.

(Prior Art) When a camera is loaded with film and the film loading lid is closed, an endless belt has claws that engage with a sprocket or film perforation (hereinafter, in this specification, both will be simply referred to as a sprocket). ) is rotated by a motor to automatically drive the loaded film leader and wind it onto a spool. Automatic loading cameras have been put into practical use.

As this type of automatic loading camera,
Publication No. 125730 states that the film leader is sent to the spool by the rotation of the sprocket, and when the film leader is wound around the spool, the sprocket is separated from the drive system using the difference between the spool circumferential speed and the sprocket circumferential speed. , a device in which a sprocket is used to detect the amount of film feed has been proposed.

However, the above type requires a clutch mechanism to cut off power transmission to the sprocket when a speed difference occurs between the sprocket and the spool, making the structure of the sprocket complicated, and the sprocket normally Since it is placed near the exposure frame, it is difficult to incorporate the above-mentioned clutch mechanism due to space constraints, and it is necessary to provide a speed difference between the spool and sprocket, which makes it difficult to decelerate the sprocket. There was a problem in that it was necessary to provide gears for this purpose, which made the mechanism even more complicated.

(Object of the Invention) The present invention provides a method for attaching the sprocket to the sprocket at the time when the film leader is wound around the spool, without using a complicated mechanism like the above-mentioned conventional devices, and without placing any restrictions on the arrangement of the sprocket portion. It is an object of the present invention to provide a film feeding device for an automatic loading camera that can reliably cut off power transmission to the camera.

(Structure of the Invention) Therefore, the present invention provides an automatic loading camera in which the leader of the film loaded in the camera body is wound around the spool by being driven by a motor-driven sprocket. A spool shaft is fitted into a fitting hole provided in the axial direction so as to be relatively rotatable, and a clutch shaft is fitted into a through hole provided coaxially within the spool shaft so as to be able to move up and down. and the spool are connected by a first gear train, and the spool shaft and the sprocket are connected by a second gear train, and the film counter mechanism of the camera is linked to the second gear train. , a clutch pin is provided that simultaneously engages a U-shaped groove formed on the upper end of the spool shaft and a long groove formed on the outer periphery of the spool when the clutch shaft is lowered, and is removed from the U-shaped groove of the spool shaft when the clutch shaft is raised; A threaded portion is formed at the lower part of the clutch shaft, and a clutch lever is provided on the threaded portion with a threaded portion that engages from the radial direction when the film loading lid is closed in conjunction with opening and closing of the film loading lid.
When loading a film, the clutch shaft is in the lowered position, and the spool shaft and spool rotate together, so that the sprocket - first gear train - spool -
When the motor is driven by the path of the second gear train and the spool is rotated a predetermined number of revolutions, the clutch shaft is raised by the thread feeding action of the threaded portion of the clutch lever, and the link between the spool shaft and the spool is released. The present invention provides a film feeding device for an automatic loading camera, characterized in that the transmission path of the driving force to the sprocket is separated.

(Effects of the Invention) According to the present invention, when the leader of the film is driven by the sprocket and wound around the spool, the link between the spool and the spool shaft is released due to the rise of the clutch shaft, and power transmission to the sprocket is interrupted. After that, the sprocket will rotate freely following the film advance. in this case,
In the present invention, since the clutch mechanism including the clutch shaft can be substantially incorporated into the spool, compact installation is possible, and there is no particular need to drive the sprocket side at a reduced speed with respect to the spool, and the structure of the sprocket side can be Power can be transmitted to and disconnected from the sprocket without any complications.

(Example) As shown in FIG. 1, a loading chamber 3 for loading a cartridge 2 is formed on the left side of the camera body in the figure when viewed from the back side, and a loading chamber 3 for loading a cartridge 2 is formed on the right side in the figure. A winding chamber 6 is formed, a sprocket 7 is arranged at the lower part near the loading chamber 3, and a counter device 8 is arranged at the upper part near the winding chamber 6.

In the spool 4, the leader 5 of the film 5 driven by the sprocket 7 is located at the lower part of the outer periphery.
When the leader 5a is driven by the sprocket 7, a film presser blade (not shown) provided around the spool 4 is attached. ) and the leader 5 by the claws 4a,..., 4a.
By hooking the perforations 5b, . A gear 4b coaxially disposed on the upper part of the spool 4 is connected to an output gear 10a of a motor 10 via a first gear train 9, and rotates in conjunction with the motor 10 to drive the film 5 (wind it up). ).

A spool shaft 11 is fitted into a fitting hole 4c provided at the axial center of the spool 4 so as to be relatively rotatable.
A gear train 1 coaxially provided at the bottom of the spool shaft 11
1a is connected to a gear 7a of a sprocket 7 via a second gear train 12, and as will be described later, when the spool 4 and the spool shaft 11 are co-rotating, the sprocket 7 rotates in conjunction with the spool 4, and the film is rotated. It is designed to drive (send) 5.

The rotating shaft 12b of the gear 12a in the middle of the second gear train 12 is extended upward, and the small-diameter driving gear 13 of the gear train 13 of the counter device 8 is attached to the upper end thereof.
a are connected, and each time the sprocket 7 rotates once, a sheet number display plate (not shown) of the counter feeding device 8 is incremented by one sheet.

In addition to the above-mentioned mechanical type, the counter device 8 is
It can also be configured to be displayed in the viewfinder as an electric type using a liquid crystal or the like.

On the other hand, as shown in FIGS. 2 and 3, a clutch shaft 14 is slidably fitted into a through hole 11b provided at the axial center of the spool shaft 11 fitted to the spool 4. At the same time, on the upper part of the clutch shaft 14, there is a clutch pin 15 that engages with the U-shaped grooves 11c, 11c formed at the upper end of the spool shaft 11 and the long grooves 4d, 4d formed in the outer peripheral wall of the spool 4. It is provided.

The clutch pin 15 simultaneously engages the U-shaped groove 11c and the long groove 4d when the clutch shaft 14 is lowered (solid line state in the figure), and connects the spool 4 and the spool shaft 11 so as to be rotatable together. When the spool 4 and the spool shaft 11 are raised (as shown by the two-dot chain line in the figure), the spool 4 and the spool shaft 11 are separated from each other so that they can rotate freely.

A spring 16 is fitted between the fitting hole 4c of the spool 4 and the clutch shaft 14, and constantly biases the clutch shaft 14 in the downward direction.

At the bottom of the clutch shaft 14, there is a male threaded portion 14 that extends (raises) in the direction of rotation of the spool 4.
A is provided.

A clutch lever 17 is provided opposite the male threaded portion 14a of the clutch shaft 14, and has a half-shaped female threaded portion 17a that can be engaged with the male threaded portion 14a from the radial direction. 18 in the anti-meshing direction.

The pitch (lead) caused by the screw feeding action of the male threaded portion 14a of the clutch shaft 14 and the female threaded portion 17a of the clutch lever 17 is caused by the co-rotation of the spool 4 and the sprocket 7, and the leader of the film 5 driven by the sprocket 7. After the perforation 5b of 5a is engaged with the pawl 4a of the spool 6, the clutch pin 15 of the clutch shaft 14, which moves upward while rotating together with the spool 4, is pulled out from the U-shaped groove 11c of the spool shaft 11. Set to .

The camera body 1 is connected to the clutch lever 17.
A reset lever 19 forcibly swings the clutch lever 17 in the engaging direction when the film loading lid (not shown) is closed, and swings the clutch lever 17 in the non-engaging direction by the biasing force of a spring 18 when opened.
is provided.

With the above configuration, when the film loading lid of the camera body is opened, the reset lever 19 escapes, the clutch lever 17 is swung in the non-meshing direction by the spring 18, and the clutch shaft 14 is moved by the spring 16. The clutch pin 15 is moved downward and is engaged with the U-shaped groove 11c and the long groove 4d at the same time.

When the cartridge 2 is loaded and the leader 5a of the film 5 faces the sprocket 7 and the film loading lid is closed, the clutch lever 17 is swung in the engaging direction by the reset lever 19, and the motor 10 is turned on, the spool 4 is rotated via the first gear train 9, the spool shaft 11 is co-rotated via the clutch pin 15, and the second
The sprocket 7 is rotated via the gear train 12,
The sprocket 7 meshes with the perforation 5b of the leader 5a of the film 5, so that the sprocket 7 drives (feeds) the film 5.

The perforation 5b of the leader 5a of the driven film 5 is the claw 4a of the spool 4,...
When the film 5 is locked on the spool 4a, the film 5 is also driven (taken up) on the spool 4.

On the other hand, the clutch shaft 14, which rotates together with the spool 4 via the clutch pin 15, is connected to the clutch lever 1.
The male threaded portion 14 meshing with the female threaded portion 17a of No. 7
Since a moves forward (up) by the screw feeding action, it moves upward while rotating together, and the perforation 5b of the leader 5a of the film 5 is locked to the claws 4a of the spool 4 so that it can be wound. After two or three rotations of the spool 4, the clutch pin 15 is removed from the U-shaped groove 11c of the spool shaft 11.

Then, the co-rotation of the spool 4 and the spool shaft 11 is separated, and only the spool 4 is rotated by the motor 10.

The film 5 is driven only by the rotation of the spool 4 by the motor 10, and the perforation 5b of the film 5 driven by the spool 4 causes the sprocket 7 to follow the drive of the film 5 and rotate. , second
Counter device 8 via gear train 12 and gear train 13
will start counting.

Therefore, the counter device 8 starts counting via the sprocket 7 only when the film 5 is being reliably driven by the spool 4, so the photographer notices that the counter does not advance during shooting. Thus, it is possible to know that there is a defect in winding the film 5 onto the spool 4.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a counter device of an automatic loading counter according to the present invention, Fig. 2 is a front sectional view of the spool portion of Fig. 1, and Fig. 3 is a main part showing the engagement relationship between the spool shaft and the clutch pin. FIG. 1...Camera body, 4...Spool, 4d...
Long groove, 5...film, 5a...leader, 7...
Sprocket, 8...Counter device, 9...1st
Gear train, 10...motor, 11...spool shaft,
11b...Through hole, 11c...U-shaped groove, 12...
Second gear train, 14...clutch shaft, 14a...male threaded portion, 15...clutch pin, 17...clutch lever, 17a...female threaded portion.

Claims (1)

[Scope of Claims] 1. An automatic loading camera in which a film leader loaded in the camera body is wound around a spool by being driven by a motor-driven sprocket, wherein the leader of the film is provided in the spool in the axial direction. The spool shaft is fitted into the fitting hole so as to be relatively rotatable, and the clutch shaft is fitted into the through hole coaxially provided in the spool shaft so as to be movable up and down, and the drive motor and the spool are connected to each other. The spool shaft and the sprocket are connected by a second gear train, and the film counter mechanism of the camera is linked to the second gear train. A clutch pin is provided that simultaneously engages a U-shaped groove formed on the upper end of the spool shaft and a long groove formed on the outer periphery of the spool when the clutch shaft is lowered, and is removed from the U-shaped groove of the spool shaft when the clutch shaft is raised. A clutch lever is provided on the threaded portion with a threaded portion that engages from the radial direction when the film loading lid is closed in conjunction with the opening and closing of the film loading lid. is in the lowered position, the spool shaft and the spool rotate together, and the motor is driven by the path of the sprocket - the first gear train - the spool - the second gear train, and the spool is rotated a predetermined number of revolutions. The automatic transmission is characterized in that the clutch shaft is raised by the screw feeding action of the threaded portion of the clutch lever, the link between the spool shaft and the spool is released, and the transmission path of the driving force to the sprocket is separated. Film feeding device for loaded cameras.