JPS623794Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a film quantitative winding detection device,
More specifically, in a camera that uses a roll film with perforations perforated on the side edges, the number of perforations is electrically detected to detect the amount of film winding. The present invention relates to a winding detection device.

As is well known, in a camera using a roll film having perforations on the side edges, a film winding mechanism is used that winds a fixed amount of film using a sprocket wheel that fits into the perforation and rotates a certain amount. is generally adopted. However, such a film winding mechanism has a drawback in that the mechanical structure including the interlocking mechanism is complicated. For this reason, in recent years, as cameras with built-in autowinders or motor drive mechanisms have become popular, the film winding mechanism has been simplified and the winding of a fixed amount of film can be detected by counting the number of perforations. Various types of devices are available.

For example, a light-emitting element such as a light-emitting diode and a light-receiving element such as a photodiode are placed at positions facing each other across the perforated side edge of a photographic film, and the change in light transmittance is Apparatus has been provided for detecting quantitative film winding by counting the number of perforations. However, this detection device has a drawback in that the light from the light emitting element is incident on the photographic film. Further, a driving circuit for the light emitting element and the light receiving element is required, which has the drawback of increasing the cost.

There is also a quantitative winding detection device that counts the number of perforations by bringing an elastic movable electric contact into contact with a conductive pressure plate that presses the photographic film from the rear side through the perflation. provided. However, with this type of detection device, when the film feeding speed increases beyond a certain level, the movable electric contact piece bounces due to the step in the perforation, resulting in failure to obtain a contact signal or a malfunction signal. Therefore, there is a drawback that accurate detection cannot be performed. Further, since the movable electric contact piece slides into contact with the moving film surface, there are problems such as scratches on the film surface, which is not preferred in practice.

On the other hand, a permanent magnet to be detected is fixed to the sprocket wheel, and changes in the magnetic flux of this permanent magnet due to the rotation of the sprocket wheel are detected by a magneto-electric conversion element such as a Hall element, and the film can be wound in a fixed amount. Apparatus for detecting is also provided. However, this device has the disadvantage that it may malfunction due to the influence of external magnetic fields. Furthermore, since a special drive circuit for the magneto-electric conversion element is required, there is a drawback that the cost is high.

The purpose of the present invention is to solve the above-mentioned conventional drawbacks by bringing a signal detection roller and a conductive current-carrying roller into pressure contact with each other by sandwiching the side edges of the film, so that both rollers come into contact through perflation. An object of the present invention is to provide a quantitative film winding detection device which detects perforation and counts the perforation to know the winding amount of the film.

According to the present invention, there is no need for a sprocket drive mechanism for feeding the film a fixed amount at a time, so that the number of parts can be reduced, making it possible to reduce the size, weight, and cost of the device.

In addition, if a spool drive mechanism is adopted in a camera as a means for feeding film in conjunction with the quantitative film winding detection device according to the present invention, the slip mechanism of the winding spool becomes unnecessary, and the complicated film winding mechanism becomes unnecessary. This greatly simplifies the manufacturing cost of the camera, and in this case, the driving force for winding the film, which was conventionally generated by the slip mechanism disposed inside the spool, can be reduced. loss is eliminated by abolishing the slip mechanism,
Very little force is required to wind the film. In particular, when the spool drive mechanism is electric, the capacity of the power source battery may be small, and a compact, lightweight, power-saving camera can be provided.

Furthermore, if the driving force for winding the film is transmitted to the signal detection roller or the energizing roller, the same roller can also serve as a film feeding roller.

In addition, all the previously known advantages of devices for detecting film advance by counting the number of perforations are obtained,
Connection with a film frame number calculation device, a film frame number display device, etc. can be extremely easily performed.

Hereinafter, the present invention will be explained based on the illustrated embodiments.

As shown in Fig. 1, the film winding detection device of the present invention is disposed near the take-up spool shaft 3 between the camera body 1 and the rear cover 2. As shown in more detail in Fig. 2, the device comprises a signal detection roller 5 rotatably disposed at a position on the side of the photographic lens (not shown) of the photographic film 4 stretched inside the camera, and a signal detection sensor 6 for detecting the amount of film 4.
The main part of the signal detection roller 5 is constituted by a conductive elastic current-carrying roller 6 which is rotatably disposed so as to be in pressure contact with the signal detection roller 5 with the conductive current-carrying roller 6 sandwiched therebetween.

The above signal detection roller 5 and energization roller 6
means photographic film 4 made of the above-mentioned roll film.
It is arranged so that it can pinch and press the upper edge of the. As is well known, the photographic film 4 has perforations 4a and 4b (see Fig. 3) formed with rectangular through holes formed in both side edges thereof continuously at equal intervals. The detection roller 6 is deformed by its elasticity and fits into the upper perforation 4a, so that it can come into contact with the signal detection roller 5.

The signal detection roller 5 includes a first conductive member 5a which is a cylindrical body in which a lower roller part which is a flange is formed at the lower end, and a cylindrical body which has a separation roller part which is a flange at its lower end. Insulating member 5b
and a second conductive member 5c made of a cylindrical body having an upper roller part made of a flange part formed at the lower end thereof are sequentially fitted, and the middle part thereof is rotatably attached to the camera body 1. ing. Further, an auxiliary roller 7 is coaxially attached to the signal detection roller 5 at a position corresponding to the lower edge of the photographic film 4 through a rotating shaft 8. on the other hand,
The energizing roller 6 is made of well-known conductive rubber or the like, and is attached to upper and lower supporting pieces 2a and 2b protruding from the rear lid 2 by means of a support shaft 9, so that the photographic film 4 can be placed under the photographic film 4. Auxiliary roller 10 corresponding to the edge
It is rotatably attached.

Further, on the upper end circumferential surface of the first conductive member 5a and the upper end circumferential surface of the second conductive member 5c of the signal detection roller 5, a conductive brush 11a for extracting an electric signal from the roller 5 is provided. , 11b are in contact with each other. The brushes 11a and 11b are each connected to a counter 12 for counting the number of perforations 4a.

In FIG. 1, reference numeral 13 indicates a pressure plate for maintaining the flatness of the photographic film 4, and 14 indicates this pressure plate 1.
Leaf spring members 15a, 15b for energizing 3
Reference numeral 16 indicates a fastening member for attaching the leaf spring member 14 to the rear lid 2, and 16 indicates a cartridge for storing photographic film 4.

Next, the operation of the quantitative winding detection device of the present invention configured as described above will be explained.

First, open the rear lid 2, store the cartridge 16, and remove the photographic film 4 from the cartridge 16.
The tip of the camera is pulled out and the tip is wound around the take-up spool shaft 3. Thereafter, the rear lid 2 is closed and the film 4 is loaded into the camera. Then, the film 4 spread inside the camera is pressed against the image frame of the camera body 1 by the pressure plate 13, and
The side edges of the film are pressed against the signal detection roller 5 by the current supply roller 6. Therefore, the portion of the energizing roller 6 that comes into pressure contact with the film side edge is deformed into a planar shape due to its elasticity. In this state, if the spool shaft 3 is rotationally driven to wind up the film 4, the film 4 is fed while being wound around the spool shaft 3, so that there is a gap between the signal detection roller 5 and the energizing roller 6. of,
Perforations 4a formed on the side edges of the film 4 pass through in sequence.

When the perforation 4a comes between both rollers 5 and 6, as shown in FIG. 4a and restores itself, so that this restored portion bulges inward and restores the first and second conductive members 5 of the signal detection roller 5.
a and 5c at the same time. Therefore, since both the conductive members 5a and 5c are electrically connected by the current supply roller 6, this conductive signal is transmitted to the counter 12 through the brushes 11a and 11b, and the counter 12 counts this. Also, a perforation 4a is provided between both rollers 5 and 6.
When is not located, the energizing roller 6 does not come into contact with the signal detecting roller 5, so it goes without saying that the counter 12 does not count the perforations 4a.

In this way, since the perforation 4a passes between both rollers 5 and 6, the number of passes of the perforation 4a is counted by the counter 12, and the winding amount of the film 4 can be determined from this count number. can be done. When the amount of film 4 to be wound is less than one frame required for one shooting, the film 4 continues to be wound, and when the film 4 has been wound by one frame, the driving force of the spool shaft 3 is reduced. Then, the feeding of the film 4 is stopped.

The energizing roller 6 is not limited to a cylindrical shape, but may have a shape in which the outer circumferential surface of the portion corresponding to the perforation 4a is slightly bulged in the shape of a brim. In this way, the portion corresponding to the perforation 4a can be more easily deformed, and the contact between the energizing roller 6 and the signal detecting roller 5 can be made more reliable.

FIG. 4 shows another embodiment of the invention.
This film quantitative winding detection device includes the first to
In the apparatus shown in FIG. 3, an elastic roller 6 is used as the energizing roller 6, whereas an energizing roller 6A made of an inelastic material is used. The above energizing roller 6A of this device
is formed so that its thickness is smaller than the length in the vertical direction of the perforation 4a of the film 4,
When the perforation 4a comes to the pressure contact area between the roller 6A and the signal detection roller 5, it enters into the perforation 4a and comes into contact with the signal detection roller 5. and,
When the roller 6A contacts the signal detection roller 5, both the conductive members 5a and 5c of the roller 5 are electrically connected by the roller 6A. Also,
Since the energizing roller 6A has a small thickness, the corresponding auxiliary roller 10A has a small thickness as well. This is to prevent any difference in the pressing action against the film 4 between the rollers 6A and 10A.

The other structural members in the embodiment of FIG. 4 are the same as those of the apparatus shown in FIGS. 1 to 3, so the same reference numerals are given to the structural members and the explanation thereof will be omitted.

The film quantitative winding detection device is
It goes without saying that even with the configuration shown in the figure, the same actions and effects as the apparatus shown in FIGS. 1 to 3 can be obtained.

FIG. 5 shows yet another embodiment of the invention. This quantitative film winding detection device is based on the above device shown in FIGS.
c and an insulating member 5b, this is made of a single conductor. That is, the signal detection roller 5A is integrally formed of a single conductor, and is disposed at the same position as the signal detection roller 5. In addition, the pair of conductive brushes 21a and 21b are
One of the brushes 21a is in contact with the outer peripheral surface of the upper end of the roller 5A, and the other brush 21b is in contact with the outer peripheral surface of the energizing roller 6, and these brushes 21a and 21b are connected to the counter 12.

In addition, other constituent members in this example are as follows:
Since it is the same as that of the above-mentioned apparatus shown in FIGS. 1 to 3, the same reference numerals are given to the constituent members and the explanation thereof will be omitted.

In the film quantitative film winding detection device configured in this way, the energizing roller 6 fits into the perforation 4a and the same roller 6 contacts the signal detection roller 5A, so that the number of perflation 4a can be controlled. can be counted. Therefore, the same functions and effects as the devices shown in FIGS. 1 to 3 and 4 can be obtained.

In each of the above embodiments, the film winding mechanism of the camera was explained as a spool drive mechanism, but when the spool shaft is rotationally driven to wind the film, the signal detection roller is simultaneously driven by the drive mechanism. Of course, the film can be fed more smoothly.

Further, although the energizing roller is rotatably attached to the rear cover, it goes without saying that the roller may be attached to the camera body.
However, in this case, the energizing roller does not separate from the signal detecting roller even when the rear cover is opened, so when loading the film, insert the film between both rollers before unloading the spool. It must be wrapped around the shaft.

Furthermore, the signal detection roller and the energizing roller were arranged so as to sandwich and press the upper edge of the photographic film, but the rollers were arranged so as to sandwich and press the lower edge of the photographic film. Of course, the winding amount of the film may be detected based on the number of perforations formed in the lower edge.

As described above, according to the present invention, it is possible to solve the conventional drawbacks mentioned at the beginning of the specification and to provide a quantitative film winding detection device which is extremely convenient to use.

[Brief explanation of the drawing]

1 and 2 are horizontal sectional views and longitudinal sectional views of a film winding detection device showing an embodiment of the present invention, and FIG. 3 is a schematic view of the film winding detection device shown in FIGS. FIG. 4 is a sectional view of a film quantitative winding detection device showing another embodiment of the present invention, and FIG.
FIG. 7 is a cross-sectional view of a film quantitative winding detection device showing still another embodiment of the present invention. 2... Rear cover, 4... Photographic film, 4a, 4b
...Perflation, 5a, 5c...Conductive member, 5,5A...Signal detection roller, 5b...
Insulating member, 6,6A...roller for energization.

Claims (1)

[Claims for Utility Model Registration] (1) Film quantification using a camera that uses a roll film with perforations perforated on the side edges and counts the number of perforations that move when the film is wound. In the winding detection device, the film is placed in a position corresponding to the perforation of the photographic film stretched inside the camera, and when facing the perforation with the photographic film in between, the film is electrically conductive to each other, and the film between the perforations is connected to each other. A feature is that first and second conductive rollers that are non-conductive to each other when facing a surface are provided in pressure contact with each other, and the winding amount of the film is detected by counting the conductive signals of both rollers. Quantitative film winding detection device. (2) Attach the second conductive roller to the rear lid of the camera, so that when the lid is opened at the same time, the second conductive roller is released from pressure contact with the first conductive roller. A film quantitative winding detection device according to claim 1 of the utility model registration claim, characterized in that: (3) The first conductive roller has a pair of conductive members sandwiching an insulating member, and the second conductive roller can contact both conductive members at the same time. A quantitative film winding detection device according to claim 1 of the utility model registration claim. (4) The quantitative film winding detection device according to claim 1, wherein at least one of the first and second conductive rollers is a winding roller. (5) Quantitative film winding detection according to claim 1 of the utility model registration, characterized in that the thickness of the second conductive roller is smaller than the longitudinal length of the perforation. Device.