JPS6041548Y2 - film winding device - Google Patents

Description

[Detailed description of the invention] The invention relates to a film winding device, and more specifically, when a short film cartridge and a long film cartridge of a cine camera are installed, driving force corresponding to different winding torques can be obtained. The present invention relates to a film winding device configured as described above.

Generally, in a cine camera, a film cartridge is set in a drive unit of a camera body, and the film is run at a predetermined speed to take pictures.

When using such film cartridges,
Since the film is wound on a supply reel and a take-up reel, the winding diameter changes as the shooting progresses, and even if the film is wound at the same rotational speed, the running speed will always be different and the winding torque will also change. It arises.

On the other hand, in addition to the problem of changes in winding torque due to changes in winding diameter, there are
When replacing and using 00 feet long film,
Since the winding amount of the film cartridge itself differs by four times, there is a problem that the winding torque also naturally differs.

Conventionally, the mechanism for switching the winding torque when using such short and long film cartridges is that when the long film cartridge is set in the drive unit of the camera body, Alternatively, a structure has been adopted in which a friction plate is pressed against the side surface of the rotating plate on the driving side via a pin provided on the driving side, and a large winding torque is obtained by utilizing the frictional force generated by surface contact.

An object of the present invention is to provide a film winding device that is configured to be able to reliably switch the winding torque with an extremely simple structure without using a friction disk or the like.

In this invention, in order to achieve the above object, the drive side and the non-drive side are connected via a leaf spring that is set so that a small winding torque can be obtained when a short film cartridge is set. When a long film cartridge is set, a pressing force is applied to the friction lever via the pin, and a large winding torque is transmitted between the drive side and the non-drive side. We adopted a structure that allows for

Hereinafter, details of the present invention will be explained along with embodiments shown in the drawings.

Figure 1 and the following are illustrations of an embodiment of the present invention. In the figure, what is indicated by number 1 is a side plate that constitutes the body of the camera, and a winding gear 2 is arranged on the outside of this side plate. .

An annular wall 2a is formed on the outer surface of this winding gear 2,
Furthermore, a through hole 2b into which a shaft to be described later is fitted is formed in the center.

A pair of friction levers 3 are disposed within the annular wall 2a of the winding gear 2.
3 is accommodated.

The friction levers 3, 3 are formed in an arcuate shape, and a protruding portion 3a is provided approximately at the center of the outer surface thereof, each having an arcuate outer peripheral surface.

The base ends of the friction levers 3, 3 are located in recesses 5a of the rotating plate 5, which will be described later.
It is rotatably supported by a boss 5e located inside.

At the free ends of the friction levers 3, 3, tapered surfaces 3b are formed facing each other and having the same inclination angle.

On the other hand, what is designated by the reference numeral 5 is a rotary plate which, as is clear from the cross-sectional view in FIG. mated to.

This rotary plate 5 has a cylindrical shaft 5b on the side of the recess 5a, and this shaft 5b passes between the friction levers 3 and 3 and is fitted into the through hole 2b of the winding gear 2.

Incidentally, a plate spring 6 formed in an annular shape is fitted into a recess 5a inside the rotating plate 5.

As is clear from FIG. 1, this leaf spring 6 is bent into a wave shape, and a through hole 6a is formed in a portion thereof, that is, a portion curved toward the friction lever 3 side.

A pin 7 is fitted into the through hole 6a.

As is clear from FIG. 1, the pin 7 has a small diameter on the leaf spring 6 side and has an acute-angled tip, but the pin 7 on the friction lever 3 side has a head shaped like a warhead with a large diameter. It is 7a.

The head 7a of the pin 7 is arranged to be located between the tapered surfaces 3 by 3 b formed on the free ends of the friction levers 3, 3, and the leaf spring 6 is placed in the recess 5a of the rotary plate 5 in a corresponding state. is set for .

On the other hand, a through hole 5c into which the pin 7 is slidably fitted is formed on the outer surface of the rotary plate 5, and a guide plate having a semicircular cross section surrounds the through hole 5c. 5d is provided protrudingly.

By the way, what is indicated by the reference numeral 8 is a stud, which is attached to the side plate 1.
is fitted into the through hole 1a from the front, and rotatably supports the hollow shaft 5b of the rotary plate 5.

Next, the operation of this embodiment configured as above will be explained.

When no film cartridge is set on the rotary plate 5, or when a short film cartridge is set, the pin 7 does not contact the side surface of the film cartridge, and therefore the pin 7 does not touch the base of the head 7a. A tapered surface 3b formed at the free end of the friction lever 3.3 with a pressing force corresponding to the pressing force of the leaf spring 6 through the stepped portion.
3b is pressed.

Therefore, the friction levers 3, 3 are given a rotational force about the pin 4 in a direction in which their free ends move away from each other.

In other words, the friction lever is opened outward, and its protruding portion 3a is pressed against the inner circumferential surface of the annular wall 2a of the winding gear 2, thereby applying a predetermined frictional force.

This frictional force determines the magnitude of the winding torque transmitted from the winding gear 2, and if this winding torque is set equal to the winding torque of the short film cartridge, the optimal winding of the short film cartridge can be achieved. This will result in increased torque.

Note that the inner peripheral surface of the annular wall 2a and the protrusion 3a of the friction lever 3
Since the frictional force generated between the short film cartridge and the When the frictional force becomes larger than the frictional force, the rotary plate 5 slips and a uniform winding torque can be obtained.

On the other hand, when a long film cartridge is set on the rotary plate 5, a protrusion provided on the long film cartridge side and pressed by a spring (not shown) presses the acute-angled tip of the pin 7, so that the pin 7 is advanced and the warhead-like head 7
The tip of the friction lever 3 is fitted more deeply between the tapered surfaces 3b formed at the free end of the friction lever 3, and the friction lever 3 expands further outward, causing the protrusion 3a to press strongly against the inner circumferential surface of the annular wall 2a. A large frictional force is generated between the two, and therefore a large winding torque suitable for a long film cartridge can be obtained.

In this case, as the shooting progresses, the winding diameter of the film changes and the winding torque changes, and if the winding torque becomes larger than the frictional force, the rotary plate 5 will slip. Uniform winding torque can be obtained.

In this way, the winding torque can be automatically switched in accordance with the magnitude of the winding torque for long and short film cartridges whenever the cartridges are replaced.

Note that the pin 7 does not have to be shaped like a bullet, and may be formed into a tapered shape, for example, as shown in FIG.

As is clear from the above description, according to the present invention, a pair of friction levers formed in an arc shape within an annular wall formed on a winding gear are rotatably supported at one end thereof, and the other end is rotatably supported on a shaft. Since the pin has a warhead-shaped head placed between the formed tapered surfaces, if no film cartridge is set on the rotary plate or if a short film cartridge is set, the pin will not work properly. The friction force between the annular wall and the rotary plate can be set to be suitable for the winding torque of a short film cartridge by pressing only with a leaf spring, and when a long film cartridge is set, the pin is pressed. The friction lever is further expanded outward to generate a large frictional force, and a winding torque suitable for a long film cartridge can be obtained.

Therefore, switching of the winding torque can be done automatically by simply setting a long film cartridge.Furthermore, when the winding diameter of the film changes and the winding torque changes as shooting progresses, the winding torque can be changed over a certain limit. When the winding torque is reached, it automatically slips to obtain a uniform winding torque.

[Brief explanation of drawings]

The drawings are for explaining one embodiment of the present invention, in which Fig. 1 is an exploded perspective view, Fig. 2 is a longitudinal sectional front view, and Fig. 3 is an A-A in Fig. 2.
4 is a perspective view of the rotating plate 5 seen from the direction of half a rotation, FIG. 5 is a sectional view of another embodiment in which the bullet head of the pin is tapered, and FIG. 6 is a perspective view of the rotating plate 5. It is a perspective view seen from the back. 1... Side plate, 2... Winding gear, 2a
......Annular wall, 3...Friction lever, 3a
...Protrusion, 3b...Tapered surface, 5.
... Rotating plate, 5a ... Concavity, 5b ...
...Shaft, 5c...Through hole, 6...Leaf spring, 7...Zen, 7a...Head, butt...
···stud.

Claims (1)

[Scope of utility model registration request] A take-up gear is rotatably supported on the side of the side plate of the camera body and has an annular wall formed on its outer surface. A pair of friction levers, each of which is rotatably supported on a shaft via a shaft, and has tapered surfaces facing each other at the same inclination angle at its free ends, and a protrusion formed approximately at the center of its outer circumferential surface. and a pin whose one end is formed into a warhead shape, faces between the tapered surfaces of the friction lever, and is disposed so as to be movable in the axial direction, and the pin frictionally engages with the annular wall of the take-up gear and rotates according to the take-up gear. a rotary plate that is rotatably supported on its axis, and has a through hole in which the other end of the pin is slidably fitted in the eccentric position of the rotary plate, into which short and long film cartridges are fitted; a leaf spring that is disposed in a recess formed on the back surface of the cartridge and applies a predetermined pressing force to the pin in one direction of the friction lever, and when a long cartridge is loaded, the friction lever A film winding device characterized by applying pressing force to a lever to increase winding torque.