JPH04295845A - Photographic film cartridge - Google Patents

Abstract

PURPOSE:To prevent a static mark by discharge from being generated by providing a conductor for preventing the discharge caused between a photographic film and a plush in a cartridge main body made of resin corresponding to the plush. CONSTITUTION:When the cartridge 2 is loaded in a camera, a spool 4 is rotated in a feeding direction by a film initial feeding mechanism and the film 5 and its leading edge are rotated clockwise through a pair of flanges 4a and 4b. Thereafter, the leading edge of the film 5 is picked up from its film surface being a lower layer by a leading edge separating pawl 14 and advances to a film path 6. When the leading edge of the film 5 passes through a pair of plushes 15 and 16, static electricity having a different polarity is generated on a contact surface. Since aluminum foils 8 and 9 functioning as the conductor are fixed on a port part 7, the line of electric force of the static electricity which is electrified on the plushes 15 and 16 advances to the aluminum foils 8 and 9. Therefore, the discharge between the film 5 and the plushes 15 and 16 is prevented.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographic film cartridge made of resin that prevents electrostatic damage.

0002

2. Description of the Related Art A photographic film cartridge is comprised of a main body, which is a light-shielding container having a film outlet, and a photographic film housed inside the main body. A light-shielding telescope is fixed to the film outlet, and the photographic film slides into contact with this telescope when being taken in and out of the cartridge main body. At this time, the photographic film and the telescope are charged with static electricity having different polarities. When the cartridge main body is molded with resin, these static electricity cannot leak out, and discharge occurs between the photographic film and the telescope. Then, there is a problem in that static marks (localized exposure due to discharge) are generated on the photographic film, resulting in deterioration in quality. In order to solve this problem, photographic film cartridges that prevent the generation of static electricity and quickly leak the generated static electricity are disclosed in Japanese Patent Laid-Open Nos. 1-312537 and 1-312538. In such photographic film cartridges, a metal plate is attached to the inner surface of a resin cartridge body, or the cartridge body is molded from a conductive resin, such as a resin containing a high concentration of carbon black.

0003

However, in the former photographic film cartridge described above, a metal plate is not provided on the inner surface of the cartridge body to prevent scratches from occurring on the photographic film at the boundary between the cartridge body and the metal plate. There was a problem in that it was difficult to manufacture. In addition, the latter photo film cartridge has the problem of high manufacturing costs due to the expensive conductive resin.
Furthermore, since the conductive resin has low impact strength, there is also the problem that the thickness of the cartridge body cannot be made thin. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a photographic film cartridge which prevents the occurrence of static marks, is easy to manufacture, and is inexpensive.

0004

[Means for Solving the Problems] In order to achieve the above object, in the photographic film cartridge of the present invention, a conductor that prevents the discharge generated between the photographic film and the telescope is made of resin in correspondence with the telescope. This is provided on the main body of the cartridge.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a first embodiment of a photographic film cartridge embodying the present invention. The photographic film cartridge 2 is composed of a cartridge main body 3 consisting of a pair of casings 3a and 3b made of resin, for example, polystyrene resin, and a spool 4 containing a film wound therein. A port portion 7 is provided along the longitudinal direction on the outer circumferential surface of the cartridge main body 3, and a film passage 6 for feeding out the film is formed inside the port portion 7. A conductive material, for example, aluminum foil 8 having a thickness of 10 μm, is adhered to the upper surface of the port portion 7 along the longitudinal direction to prevent static marks. Note that an aluminum foil 9 paired with this aluminum foil 8 is adhered to the lower surface of the port section 7, as shown in FIG. Furthermore, although aluminum foils 8 and 9 are used for the port portion 7 in this embodiment, similar effects can be obtained using other metal foils or adhesive tapes coated with metal.

2 and 3 showing the inside of the photographic film cartridge 2, flanges 4a and 4b are formed at both ends of the spool 4, respectively. Further, ribs 10 and 11 are provided on both side surfaces of the cartridge body 3, respectively, and these ribs 10 and 11 are deformed as shown in the figure when pressed from the outside against the pair of flanges 4a and 4b. The pair of deformed flanges 4a and 4b sandwich the film 5 at both ends thereof to prevent the film from becoming loose. This results in
The rotation of the spool 4 is transmitted to the outermost peripheral surface of the film 5 via the flanges 4a and 4b. Furthermore, Patrone main body 3
A pair of ring-shaped inner circumferential ribs 12 and 13 are formed on the inner circumferential surface of the film 5. The inner circumferential ribs 12 and 13 abut against the ends of the film so as not to cover the central image area of the film to prevent the film 5 from becoming loose.

A tip separating claw 1 is provided at one end of the inner circumferential rib 12.
4 is formed, and this tip separation claw 14 separates the film 5.
The tip of the film is peeled off from the outer peripheral surface and sent out in the direction of the film path. Terremps 15, 1 are provided on the upper and lower inner walls of the port portion 7.
6 is fixed to the film passage 6, and these telescopes 15 and 16 shade the film passage 6 and prevent outside light from entering.

The operation of the photographic film cartridge of the present invention will be explained below. When the photographic film cartridge 2 is loaded into the camera, the spool 4 is rotated in the feeding direction by the film initial feeding mechanism of the camera. When the spool 4 rotates in the delivery direction, the film 5 and its leading end rotate clockwise in FIG. 1 via the pair of flanges 4a and 4b. (At this time, static electricity of different polarity is generated on the contact surface between the film 5 and the inner peripheral ribs 12 and 13,
Each is charged. Note that when these static electricity is discharged, the film 5 is locally exposed to light, but since this area is outside the image area, the quality of the film 5 is not impaired. )

After that, the tip of the film 5 is attached to the tip separating claw 1.
4, the film is scooped up from the lower film surface and directed toward the film path 6. When the leading edge of the film 5 passes between the pair of telescopes 15 and 16,
Static electricity of different polarity is generated on the contact surface between the film 5 and the telescopes 15 and 16. Port part 7 has aluminum foil 8,
Since the aluminum foils 9 are fixed, lines of electric force of static electricity charged on the telescopes 15 and 16 are directed toward the aluminum foils 8 and 9, respectively. For this reason, film 5 and telemp 15,1
Discharge is prevented within 6 seconds, and no static mark is generated in the image area of the film 5 fed out of the cartridge main body 3 due to the discharge. In this embodiment, the aluminum foils 8 and 9 are exposed on the surface of the cartridge main body 3, but the effect may change even if a paper label with the product name, etc. written on it is pasted on the top surface of the aluminum foils 8 and 9. There is no.

FIG. 4 shows a second embodiment of the photographic film cartridge of the present invention. In this embodiment, the outer circumferential surface of the cartridge body 3 and the outer surface of the port section 7 are covered with an adhesive tape 20 made of vapor-deposited aluminum. In the photographic film cartridge 2 configured in this manner, it is possible to prevent not only the discharge between the film 5 and the telescopes 15 and 16 but also the discharge between the film 5 and the inner peripheral ribs 12 and 13 described above. . FIG. 5 shows a third embodiment of the photographic film cartridge of the present invention. In this embodiment, the port section 7
Insert aluminum foils 8 and 9 into the upper and lower casings 3.
A and 3b are each integrally molded. FIG. 6 shows a fourth embodiment of the photographic film cartridge of the present invention. In this embodiment, the above-mentioned aluminum foils 8 and 9 are provided between the inner wall of the film passage 6 and the telescopes 15 and 16.

The photographic film cartridges of each of the above-mentioned examples and the photographic film cartridge without a conductor in the port portion as a comparative example were each left for 24 hours at a room temperature of 25 degrees Celsius and a relative humidity of 10%, and then stored in a dark room. After rapidly pulling out the film from the main body of the cartridge, each film was developed and examined for the occurrence of static marks. As a result, static marks were detected in the image area of the film in the photographic film cassette as a comparative example, whereas static marks were not detected in the image area of the film in the photographic film cassette of each example.

[0012]Furthermore, the films pulled out from the cartridge bodies of each of the Examples and Comparative Examples were placed in a Faraday gauge and the amount of charge was measured, but no difference was observed between the films. These results show that the conductor prevents discharge from occurring between the film and the telescope. Furthermore, it can be seen that the discharge does not require the conductor to contact the film.

[0013]

Effects of the Invention As described above in detail, in the photographic film cartridge of the present invention, a conductor for preventing discharge generated between the photographic film and the telescope is attached to the resin cartridge main body to correspond to the telescope. Since it is provided in the area, it is possible to prevent the generation of static marks. Furthermore, since the conductor does not need to be in contact with the photographic film,
This can be easily incorporated during manufacturing, so
The cost can be reduced.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a first embodiment of a photographic film cartridge of the present invention.

FIG. 2 is a partially cutaway side view of the photographic film cartridge shown in FIG. 1;

3 is a sectional view of the photographic film cartridge shown in FIG. 1. FIG.

FIG. 4 is a cutaway view showing a second embodiment of the photographic film cartridge of the present invention.

FIG. 5 is an enlarged sectional view of a main part of a third embodiment of the photographic film cartridge of the present invention.

FIG. 6 is an enlarged sectional view of a main part of a fourth embodiment of the photographic film cartridge of the present invention.

[Explanation of symbols]

2 Photo film patrone 3 Patrone body 5 Film 6 Film aisle 7 Port section 8,9 Aluminum foil 15,16 Telemp

Claims (1)

[Claims] Claim 1: A cartridge main body made of resin for storing photographic film; a film passage provided in the cartridge main body through which the photographic film is fed; This photographic film cartridge is characterized by comprising: a telescope for shielding light; and a conductor provided on the main body of the cartridge corresponding to the telescope to prevent discharge occurring between the photographic film and the telescope.