JP3723271B2 - Film loading method for film unit with lens - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a film loading method for a film unit with a lens, and more particularly, to prevent the film scroll from protruding out of the film scroll chamber when the take-up shaft is pulled out from the film scroll inserted into the film scroll chamber. The present invention relates to a film loading method for a film unit with a lens.
[0002]
[Prior art]
A unit with a simple exposure mechanism is loaded with a photographic film with a cartridge in advance at the manufacturing stage to eliminate the need for loading and rewinding the photographic film. ) Is commercially available. This unit main body is formed with a cartridge storage chamber for storing a cartridge, and a film scroll chamber for storing a film scroll in which a photographic film drawn out of the cartridge is wound in a scroll form, and a main body base incorporating a simple exposure mechanism. And a front cover that covers the front side of the base of the main body and a lid that covers the bottoms of the cartridge storage chamber and the film scroll chamber are integrally formed via hinges to cover the back side of the main body in a light-tight manner. It consists of a rear cover.
[0003]
To assemble the lens-fitted photo film unit, an exposure mechanism is incorporated into the base of the main body in a bright room, and then a front cover is attached to the front side of the main body base. On the other hand, in the dark room, a photographic film is pulled out from the cartridge and wound around the take-up shaft to create a film scroll. After the main unit base is carried into the dark room, the cartridge is inserted into the cartridge storage chamber of the main unit base, the tip end of the spool is engaged with the engaging shaft formed integrally with the winding knob, and then the film scroll is taken together with the winding shaft. Insert into the film scroll chamber.
[0004]
The bottom wall of the film scroll chamber is formed with a U-shaped notch through which the take-up shaft passes. On the other hand, a protrusion having a semicircular cutout is integrally formed on the rear cover. When the rear cover is mounted on the back side of the main body base, the projection of the rear cover enters the U-shaped notch in the bottom wall of the film scroll chamber to form a substantially circular hole, and the winding shaft is exposed to the outside from this hole. Protruding state. Thereafter, when the take-up shaft is pulled out, the end face of the film scroll is regulated by the bottom wall of the film scroll chamber and the protrusion of the rear cover, and the film scroll remains in the film scroll chamber. After that, each lid portion of the rear cover is rotated about the hinge portion and pressed against the main body base side, so that each lid portion engages with each bottom portion of the cartridge storage chamber and the film scroll chamber, and each chamber is Closed light tightly. The film unit with lens is completed by covering the unit main body thus assembled with a paper outer case.
[0005]
[Problems to be solved by the invention]
By the way, when the take-up shaft is rubbed against the edge of the hole when the take-up shaft is pulled out from the film scroll, the edge of the hole is scraped to produce resin dust. For this reason, a clearance of about 0.5 mm is provided between the winding shaft and the edge of the hole. However, due to this clearance, the innermost part of the film scroll that is in close contact with the take-up shaft becomes a bamboo shoot from between the take-up shaft and the edge of the hole, causing a phenomenon that protrudes outside the base of the main body. And it is a problem.
[0006]
The present invention has been made to solve such a problem, and the film scroll is formed into a bamboo cocoon shape to prevent the film scroll from protruding from between the winding shaft and the edge of the hole to the outside of the base of the main body. It is an object of the present invention to provide a film loading method for a lens-fitted photo film unit capable of reliably performing the above.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the film loading method of the lens-fitted photo film unit of the present invention creates a film scroll by winding a photographic film around a take-up shaft, and the film scroll is attached to the base of the main body together with the take-up shaft. After being inserted into the formed film scroll chamber, the back side of the main body base is covered with the rear cover, and then the take-up shaft is pulled out, so that the bottom wall of the film scroll chamber and the rear cover provided at the corresponding position are provided. In the film loading method of a film unit with a lens in which the end face of the film scroll is regulated by the projection of the film scroll and the film scroll remains in the film scroll chamber, at least the projection of the bottom wall of the film scroll chamber or the projection of the rear cover end of the other hand, the film scroll close to the peripheral surface of the winding shaft And forming integrally the film pressing piece for restricting the, in the axial direction of the winding shaft, is obtained by forming a slit in which the film pressing piece enters. The slit of the winding shaft is formed by forming at least one edge of the front opening with a large radius of curvature.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 2, the unit main body 11 of the lens-fitted photo film unit has a main body base 15 that houses a photographic film 12 with a cartridge on the back side, a rear cover 16 that covers the back side, and a front side of the main body base 31. It consists of a front cover 17 for covering. Although not shown, a simple exposure mechanism is attached to the front side of the main body base 15.
[0009]
A film scroll chamber 22 for storing the film scroll 12a and a cartridge storage chamber 23 for storing the cartridge 20 are formed on the back side of the main body base 15 with the aperture 18 interposed therebetween. The film scroll 12 a is created by winding the photographic film 12 drawn out from the cartridge 20 around the take-up shaft 25 in a scroll form.
[0010]
A slit 25 a into which the leader portion 12 b (see FIG. 1) of the photographic film 12 is inserted is formed in the front end portion of the winding shaft 25 in the axial direction. The slit 25 a is formed to be slightly longer than the range in which the photographic film 12 is wound from the tip of the winding shaft 25. That is, when the film scroll 12a is created, the slit 25a on the base 25b side of the take-up shaft 25 is exposed beyond a predetermined length so that a film pressing piece, which will be described later, enters the slit 25a. Further, as shown in FIG. 1, the slit 25a has a wide opening and a narrow back (center portion of the winding shaft 25). As a result, a film pressing piece, which will be described later, can easily enter, and the front end of the photographic film 12 can be easily held behind the slit 25a. Further, the edge of the frontage is formed with a large radius of curvature so that the photographic film 12 is not easily broken.
[0011]
On the bottom side of the film scroll chamber 22, a bottom wall 24 formed in an arc shape with a substantially predetermined width is provided along the peripheral surface of the film scroll chamber 22. At the center of the bottom wall 24, a tongue-shaped film pressing piece 24a is formed. As shown in FIG. 1, when the film scroll 12a is inserted into the film scroll chamber 22 together with the take-up shaft 25, the film pressing piece 24a enters the front end portion where the width of the slit 25a is widened, as shown in FIG. The end surface of the film scroll 12a wound in the vicinity is regulated, and when the take-up shaft 25 is pulled out from the film scroll 12a, the end surface near the take-up shaft 25 is prevented from protruding like a bamboo slab.
[0012]
Note that both end portions 24b and 24c of the bottom wall 24 are slightly thinner and are in close contact with the inner wall surfaces of the protrusions of the rear cover 16 described later. Engaging claws 27 a, 27 b, 27 c and 27 d for mounting the rear cover 16 to the main body base 15 are formed on the bottom and top of the main body base 15. Further, engaging claws 27 e and 27 f for attaching the front cover 17 to the main body base 15 are formed on the side of the main body base 15.
[0013]
At a position corresponding to the bottom wall 24 of the rear cover 16, a protrusion 30 is formed with a central portion cut out in an arc shape. A film pressing piece 30 a similar to the film pressing piece 24 a of the main body base portion 15 is formed at an intermediate portion of the edge of the protruding portion 30. When the rear cover 16 is attached to the back side of the main body base portion 15, as shown in FIG. 1, the inner wall surfaces of both end portions 30 b and 30 c of the projection portion 30 are in close contact with both end portions 24 b and 24 c of the bottom wall 24. An insertion hole 35 through which the take-up shaft 25 is inserted is formed by 24 and the protrusion 30.
[0014]
On the left and right sides of the bottom side edge of the rear cover 16, lids 28 and 29 for closing the bottoms of the film scroll chamber 22 and the cartridge storage chamber 23 of the main body base 15 light-tightly by nail engagement are thin hinge portions. They are integrally formed via 31 and 32, respectively. In the bottom 33, engagement holes 33a and 33b are formed at positions corresponding to the engagement claws 27a and 27b. Further, engaging claws 34a and 34b are formed at positions corresponding to the engaging claws 27c and 27d.
[0015]
On the side of the front cover 17, notches 17 a and 17 b that are engaged with the engaging claws 27 e and 27 f of the main body base 15 are formed. Further, an engagement claw 17c is formed on the front back surface of the front cover 17, and is engaged with an engagement claw formed on the front portion of the main body base 15 (not shown).
[0016]
In order to assemble the unit main body 11, first, an exposure mechanism, a strobe device or the like is attached to the front side of the main body base 15 on a separate line, and a front cover 17 is further attached. When the front cover 17 is mounted, the front cover 17 is put on the front side of the main body base 15 and pressed. Thereby, the notches 17a and 17b of the front cover 17 are engaged with the engaging claws 27e and 27f of the main body base portion 15, and the engaging claws (not shown) of the main body base portion 15 and the engaging claws 17c of the front cover 17 are engaged. Then, the front cover 17 is locked to the front surface of the main body base 15.
[0017]
On the other hand, the photographic film 12 is pulled out from the cartridge 20 in the dark room, and the leader portion 12 b is inserted into the slit 25 a of the take-up shaft 25. Then, the winding shaft 25 is rotated to wind the photographic film 12 around the winding shaft 25 to create a film scroll 12a. At this time, the film scroll 12a is made close to the distal end side of the take-up shaft 25 so that the slit 25a on the base 25b side of the take-up shaft 25 is exposed.
[0018]
When the main body base 15 to which the front cover 17 is attached is carried into the assembly line in the dark room, the cartridge 20 is lowered from the state shown in FIG. 2, and the spool 42 of the cartridge 20 is integrally formed with the winding knob 44. The cartridge 20 is inserted into the cartridge storage chamber 23 so as to engage with the shaft 44a. Next, the film scroll 12 a is lowered together with the take-up shaft 25 while the position of the slit 25 a is aligned with the film pressing piece 24 a, and the film scroll 12 a is inserted into the film scroll chamber 22.
[0019]
Subsequently, the rear cover 16 is put on the back side of the main body base 15 and pressed toward the main body base 15. The engagement holes 33a and 33b of the rear cover 16 are engaged with the engagement claws 27a and 27b of the main body base 15, the engagement claws 34a and 34b are engaged with the engagement claws 27c and 27d, and the rear cover 16 is engaged with the main body base 15. Installed. As a result, the film pressing piece 30a of the protrusion 30 is inserted into the slit 25a, and the insertion hole 35 is formed by the bottom wall 24 and the protrusion 30, from which the take-up shaft 25 protrudes to the outside. Become.
[0020]
Thereafter, when the take-up shaft 25 is pulled away from the film scroll chamber 22, the outer end surface of the film scroll 12a is regulated by the bottom wall 24 of the main body base 15 and the inner wall surfaces of the protrusions 30 of the rear cover 16, In addition, since the inner end face of the film scroll 12a is restricted by the film pressing pieces 24a and 30a, the take-up shaft 25 is pulled out from the film scroll 12a without the photographic film 12 being in the shape of a bamboo and protruding from the insertion hole 35. . As a result, the film scroll 12a remains in the film scroll chamber 22 with the end faces aligned.
[0021]
Next, the lid portions 28 and 29 of the rear cover 16 are rotated to close the film scroll chamber 22 and the cartridge storage chamber 23 in a light-tight manner. The unit main body 11 which has been loaded in this way is transported from the assembly line in the dark room to the test line in the bright room. The unit main body 11 undergoes film winding and exposure mechanism operation tests, and then is carried into a separate line and covered with an outer case to complete a lens-fitted film unit.
[0022]
In FIG. 3 showing another embodiment, the winding shaft 41 is different in the shape of the slit 41 a from the above-described embodiment, and the slit 41 a is formed at a position shifted from the center of the cross section of the winding shaft 41. One opening 42 of the slit 41a has a shape that is wide open to insert the leader portion 12b of the photographic film 12, and the one edge 42a is formed with a large curvature radius. The other opening 43 has a shape that holds the leading end of the leader portion 12b in a state of being bent at a substantially right angle so that the leader portion 12b does not easily detach from the slit 41a.
[0023]
The film pressing piece 44 is formed on the protrusion 46 of the rear cover 45 and is not provided on the bottom wall 49 of the main body base 48. In addition, when inserting the film scroll 12a into the film scroll chamber 50, it inserts so that the larger opening 42 may become an upper side (rear cover 45 side). Conversely, the film pressing piece may be provided on the bottom wall 49 side of the main body base portion 48 and may not be provided on the protruding portion 46 side of the rear cover 45. In this case, the film scroll 12a is inserted into the film scroll chamber 50 with the frontage 43 facing upward.
[0024]
Of course, the slit shape of the take-up shaft and the shape of the film pressing piece according to the present invention are not limited to the above embodiment. Further, instead of the slit into which the film pressing piece enters, for example, a groove may be formed on the winding shaft. In this case, as a mechanism for holding the front end of the photographic film on the take-up shaft, for example, a recess is formed in a part of the peripheral surface of the take-up shaft, and a pressing spring or the like for holding the front end of the photographic film is provided on this. Is good.
[0025]
【The invention's effect】
As described above, according to the film loading method of the present invention, at least one of the bottom wall of the film scroll chamber or the projection of the rear cover regulates the end surface of the film scroll adjacent to the peripheral surface of the take-up shaft. Since the pressing piece is integrally formed, when the take-up shaft is pulled out from the film scroll, the film can be loaded without projecting the end face of the film scroll into a bamboo shoot shape. Further, since the slit into which the film pressing piece enters in the axial direction of the take-up shaft is formed, the position of the end face of the film scroll can be surely restricted, and the end face of the film scroll can be prevented from protruding in the shape of bamboo. In addition, since the edge of at least one of the slits is formed with a large radius of curvature, the film pressing piece can easily enter the slit, and the leader portion of the photographic film can be prevented from being broken.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a relationship between a slit of a winding shaft according to the present invention, a bottom wall of a main body base, and film pressing pieces of a protrusion of a rear cover.
FIG. 2 is an exploded perspective view of a lens-fitted photo film unit embodying the present invention.
FIG. 3 is an explanatory diagram showing another embodiment of the present invention.
[Explanation of symbols]
11 Unit body 12 Photo film 12a Film scroll 15, 48 Main body base 22, 50 Film scroll chamber 24, 49 Bottom wall 24a, 30a, 44 Film holding piece 25, 41 Take-up shaft 25a, 41a Slit 30, 46 Protrusion 35 Insertion Hole

Claims (2)

A photo scroll is wound around the take-up shaft to create a film scroll. The film scroll is inserted into the film scroll chamber formed in the base of the main body together with the take-up shaft, and then the back side of the main body is covered with a back cover. Next, by pulling out the take-up shaft, the end surface of the film scroll is regulated by the bottom wall of the film scroll chamber and the projection of the rear cover provided at the corresponding position, and the film scroll remains in the film scroll chamber. In the film loading method of the lens-equipped film unit,
At least one of the bottom wall of the film scroll chamber or the protrusion of the rear cover is integrally formed with a film pressing piece for regulating the end face of the film scroll adjacent to the peripheral surface of the winding shaft, and the winding shaft A film loading method for a film unit with a lens , wherein a slit into which the film pressing piece enters is formed in an axial direction . The slit film loading method of the lens-fitted photo film unit according to claim 1, characterized by forming the edges of at least one of the frontage with a large radius of curvature.

Images