JP3927213B2 - Film unit with lens - Google Patents

Description

  The present invention relates to a lens-fitted photo film unit that prevents film movement during exposure.

  A film unit with a lens that has a simple exposure mechanism and is pre-loaded with unexposed photographic film and cartridges at the time of manufacture, eliminating the need for cumbersome film loading and rewinding operations. ) "Etc. are manufactured and sold by the applicant. In such a lens-fitted photo film unit, an exposed photographic film is wound up in the patrone by rotating the winding knob engaged with the patrone spool each time shooting is performed, and the shutter of the photographic film is transferred by using the transfer of the photographic film at this time. After charging, the locking lever of the exposure mechanism engages with the tooth row formed on the outer periphery of the winding knob to prevent further rotation of the winding knob.

  Also, in such a film winding mechanism, when the film winding operation is performed, if the winding knob is rotated in the direction opposite to the film winding direction, the exposed frame is pulled out from the cartridge. A reverse operation preventing mechanism for preventing the operation is provided. This mechanism is composed of a tooth row formed on the outer periphery of the winding knob and a reverse rotation preventing claw that elastically engages the tooth row. The reversing prevention pawl elastically deforms to allow its rotation when the winding knob is rotated forward in the film winding direction, and enters the trough of the dentition when rotating the winding knob. To prevent.

On the other hand, in the Advanced Photo System (APS) introduced in Non-Patent Document 1, this film base is used to store a photographic film having a larger number of frames (for example, 40 frames) in a smaller patrone. It has been proposed to use annealed polyethylene naphthalate (A-PEN) having high rigidity and sufficient strength even when the thickness is reduced.
Magazine "Photographic Industry" (Photographic Publishing Co., Ltd. December 1994 issue p.11)

  However, it has been found that when a new type of photographic film as described above is used in a lens-fitted photo film unit, screen blur sometimes occurs during shooting. There are various possible causes for this. For example, when a photographic film is rolled up, a tensile force is applied to the photographic film, and this is in a state where it is stored by a winding stop mechanism. Since the winding stop is released simultaneously with the release operation, the pulling force applied to the photographic film at this moment is loosened, and the photographic film having high rigidity vibrates.

  Also, when the shutter is charged, the photographic film between the winding knob and the driven sprocket is in tension, and when this is released at the moment of the release operation, the rigid photographic film is in its original curled state. The curl contraction that tries to return to the position occurs and vibrates. Also, depending on the rotation position of the winding knob during shutter charging, the reverse rotation prevention claw may be biased in the direction of rotating the winding knob in the winding direction due to the meshing of the winding knob tooth row and the reverse rotation prevention claw. There is. If the release operation is performed in such a state, the photographic film moves to the patrone side at the moment when the winding is released, and screen blurring occurs.

  In addition, the new type of cartridge uses a rotating light-shielding lid without using a conventional temperament at the film entrance. For this reason, when the light shielding lid is opened and the photographic film protrudes from the film entrance, the photographic film can freely move within the range of the opening size of the film entrance. Therefore, the photographic film being exposed may move due to a shock caused by the swing of the shutter blades.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a lens-fitted photo film unit in which image movement is improved by preventing film movement during exposure.

  The lens-fitted photo film unit of the present invention is pre-loaded with a photographic film using annealed polyethylene naphthalate (A-PEN) on the film base, and rotated in accordance with the film transfer accompanying the winding operation of the photographic film. In the film unit with a lens provided with the driven sprocket of the shutter charge mechanism for performing the shutter charge, the shutter charge mechanism is provided with means for preventing the rotation of the driven sprocket during exposure of the photographic film. The means is characterized in that a locking lever for locking the shutter driving lever in the charging position engages with the driven sprocket during the exposure of the photographic film to prevent its rotation.

  Further, according to the film unit with a lens of the present invention, since the driven sprocket is fixed during exposure, the amount of movement of the film during exposure can be extremely reduced, which can contribute to improvement in image quality.

  In FIG. 1 showing the appearance of an embodiment of the present invention, a lens-fitted photo film unit 2 includes a unit main body 3 incorporating a photographic film with a cartridge and various photographing mechanisms, and a belt-like shape wound around and pasted in the vertical direction at the center. Label 4. On the left and right sides of the unit body 3 not covered by the label 4, a winding knob 5, a shutter button 6, a strobe light emitting unit 7, and a charging switch 8 are arranged. A hole for exposing 11 etc. is provided.

  2 to 4 showing the shutter charge mechanism of the present embodiment, the engagement between the locking lever 91 and the shutter drive lever 92 of the shutter charge mechanism is an engagement projecting downward from the locking lever 91. This is done by abutment of the protrusion 94 and the lower step portion 95a of the engaged protrusion 95 protruding upward from the shutter drive lever 92. Further, the claw portion 91a of the locking lever 91 has a substantially rectangular shape so as to be in contact with the edge of the pressing protrusion 67b without a gap when inserted into the groove 97a of the winding cam 97.

  When the shutter button 6 is pressed, the pressing rod formed at the lower portion of the shutter button 6 presses the falling piece 91c of the locking lever 91, and the locking lever 91 is counterclockwise as shown in FIG. It is rotated. The claw portion 91a of the locking lever 91 is slightly engaged with the pressing protrusion 67b even just before the engagement of the engagement protrusion 94 and the engagement protrusion 95 is released.

  When the locking lever 91 is further rotated counterclockwise from the position shown in FIG. 3, the engagement between the engaging projection 94 and the lower step 95 a of the engaged projection 95 is released, and the first spring 52 is attached. Due to the force, as shown in FIG. 4, the shutter drive lever 92 is rotated counterclockwise. When the shutter driving lever 92 is rotated counterclockwise, the action piece (not shown) of the shutter blade is kicked by the kicking arm 92a, and the shutter opening is opened and closed by the swinging of the shutter blade. Exposure is performed.

  In the vicinity of the engaging protrusion 94 of the locking lever 91, a convex portion 99 is integrally formed. As shown in FIG. 4, when the shutter driving lever 92 rotates counterclockwise during the shutter release, the upper portion 95b of the engaged projection 95 is abutted against the convex portion 99. In the first spring 52 and the second spring 53, since the biasing force of the second spring 53 is weaker, the locking lever 91 is rotated counterclockwise against the biasing of the second spring 53, and the claw The portion 91a is pulled out of the groove 97a of the winding cam 97, the winding claw 91b is separated from the tooth row 5a of the winding knob 5, and the film winding is released. As a result, the subsequent photographic film 22 can be wound up.

  In this way, after the engagement between the engaging projection 94 and the lower step portion 95a of the engaged projection 95 is released and the shutter opening is opened and closed, the claw portion 91a is released from the groove 97a of the winding cam 97. The rotation of the driven sprocket 98 in the counterclockwise direction (winding direction) is prevented. Further, during this time, the winding knob 5 is prevented from being reversely rotated (clockwise) by the reverse rotation preventing claw, so that the moving range of the photographic film 22 is from when the shutter is charged until the exposure of the photographic film 22 is completed. Since there is only a gap between the perforation of the photographic film 22 and the teeth 98a of the driven sprocket 98, the amount of movement of the photographic film 22 is extremely reduced, and the image quality is improved.

  The embodiment described above is a film unit with a lens loaded with a novel photographic film cartridge. However, a film unit with a lens loaded with a conventional 135 type cartridge and an A-PEN-based photographic film may be used.

It is a perspective view which shows the external appearance of the film unit with a lens of this invention. It is a top view which shows the shutter charge mechanism at the time of film winding stop. It is a top view which shows the shutter charge mechanism just before a shutter release. It is a top view which shows the shutter charge mechanism after the shutter release completion | finish.

Explanation of symbols

2 Film unit with lens 5 Winding knob 6 Shutter button 22 Photo film 98 Driven sprocket 92 Shutter drive lever 95 Engagement protrusion 91 Locking lever 94 Engagement protrusion 97 Winding cam

Claims (2)

A photographic film using annealed polyethylene naphthalate (A-PEN) is pre-loaded on the film base, and the shutter charge mechanism is driven to rotate and rotate according to the film transfer accompanying the winding operation of the photographic film. In film unit with lens with sprocket,
A film unit with a lens, wherein the shutter charge mechanism is provided with means for preventing rotation of a driven sprocket during exposure of a photographic film. The means is characterized in that a locking lever for locking a shutter drive lever of the shutter charge mechanism at a charging position engages with the driven sprocket to prevent its rotation during exposure of the photographic film. The film unit with a lens according to claim 1.

Images