JPH1090832A - Sheet film pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the mechanical strength of a draw cover and to prevent breakage and deformation of the rim of an engaging hole by melt extruding a specified polycarbonate resin to mold the draw cover. SOLUTION: This sheet film pack comprises a box-shaped main pack 3 having a freely detachable cap member 2 at the end, and plural sheet film units 4 laminated and stored in it, and the draw cover 5 with a grip 5a for opening and closing an opening 3a formed in the upper part of the main pack. The draw cover 5 can be slid along the grooves 8a, 8a of a pair of guide rails 8, 9 fitted on both rims of the pack 3 by pushing and pulling the grip 5a. The draw cover 5 is made by extrusion molding of the polycarbonate resin with a 0.5-2.0weight% silicon added, and this polycarbonate resin to be used has a tensile strength of >=550kg/cm<2> and a Young's modulus in flexure of >=20,000kg/cm<2> and a melt flow index of 5g/10min.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a sheet film pack in which a plurality of sheet films are stacked and stored, and images are sequentially taken on these sheet films.

[0002]

2. Description of the Related Art A sheet film pack is used by being loaded in a pack holder, and enables continuous photographing with a large camera by pushing and pulling a lid. In the pack body of the sheet film pack, a plurality of sheet film units each containing a 4 × 5 inch sheet film housed in a sheath are housed in a stack. Also,
A pressure plate spring is provided on the bottom surface of the inner wall of the pack body to bias the stacked sheet film units upward of the pack body.

After the film pack is loaded into the pack holder and the lid of the pack holder is closed, the lid is pulled to the full, and a locking claw provided on the holder body side is formed at the tip of the lid. The lid is engaged with the locking hole to prevent the lid from coming off. As a result, the opening of the pack main body is fully opened, and the uppermost sheet film unit moves from the opening of the pack main body to the exposure position of the holder main body. A plurality of leaf springs for urging the exposed sheet film unit to the bottom surface of the inner wall of the holder main body are attached to the upper inner wall of the holder main body in which the exposure position is defined and the exposure opening is formed.

When the lid is returned to its original position, the lid is inserted between the uppermost sheet film unit and the next sheet film unit. Then, when the shutter is opened and closed, the photographing is performed, and then the lid is pulled, the middle frame provided inside the holder main body slides out while holding the pack main body. At this time, the exposed sheet film unit is stopped at the exposure position by being engaged with the ridge formed on the inner wall of the holder main body. Pressed.

Subsequently, when the lid is pushed back to the original position, the pack body together with the middle frame returns to the original position of the holder body. At this time, the exposed sheet film unit is stored in the lowermost layer of the stacked sheet film unit from the opening between the lower end of the partition plate and the bottom surface of the pack body. By repeating the above operation, it is possible to continuously photograph all the sheet film units stored in the pack body.

[0006]

As described above, when the pull lid is pulled out to the full in preparation for photographing, the locking claw on the holder main body engages with the locking hole of the lid, and further pull lids are engaged. To prevent the withdrawal. For this reason, when the lid is pulled vigorously, excessive force is applied to the edge of the locking hole of the lid, and this portion may be deformed or chipped. In addition, when returning the lid once pulled out, the lid is inserted between the uppermost sheet film unit and the next sheet film unit, so that the front and back surfaces of the lid are sandwiched between two sheet film units. Rubbed. If the resistance generated at this time is large, the vibration of the pulling lid operation is transmitted to the camera. Therefore, if the release operation is performed immediately after this, there is a problem that a focus defect occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a sheet film pack in which the mechanical strength of the lid is reduced and the operating resistance is reduced.

[0008]

In order to achieve the above object, a sheet film pack according to the present invention stores a plurality of sheet film units in which one sheet film is held flat by a sheath. The pack body,
A sheet film pack, comprising: an opening formed in a front wall of the pack main body and exposing the uppermost sheet film unit; and a slide lid slidably provided in the pack main body and opening and closing the opening. Is injection molded using a polycarbonate resin containing 0.5% to 2.0% of silicon.

The silicone-added polycarbonate resin has a tensile strength of 550 kg / cm ² or more and a flexural modulus of 20
000kg / cm ² or more and melt flow index is 5
g / 10min to 20g / 10min.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a sheet film pack 1 to which the present invention is applied is housed in a box-shaped pack body 3 having a detachable cap member 2 at an end portion, and stacked therein. A plurality of, for example, eight, sheet film units 4 are provided, and a lid 5 with a handle 5a for opening and closing an opening 3a formed in an upper portion (a side to be attached to the camera) of the pack body 3. The sheet film unit 4 is 4
It is composed of a sheet film 6 having a size of 5 inches and a plastic sheath 7 for accommodating the sheet film.

The lid 5 is larger in size than the sheet film unit 4, and is pushed and pulled with the handle 5a to form grooves 8a, 9a of a pair of guide rails 8, 9 formed on both edges of the pack body 3. Can be slid along. As shown in FIG. 2, the sheet film pack 1
Prior to the loading of the cap 5 into the pack holder 10, the lid 5 has a pair of claw portions 12 in which a pair of locking holes 5 c and 5 d formed in the distal end portion 5 b are formed in the claw member 12 of the cap member 2.
a and 12b, and a ridge 5e provided near the handle 5a contacts the end of the pack body 3 and is locked at a position to close the opening 3a.

As will be described later, after the film pack 1 is loaded into the pack holder 10 and the lid 51 of the pack holder is closed, the pulling lid 5 is pulled to the full, and the locking claws provided on the holder main body 10a side The lid 5 is engaged with the locking holes 5c and 5d to prevent the lid 5 from coming off. That is, since a large force is applied to the edges of the locking holes 5c and 5d, the lid 5 according to the present invention is injection-molded using a polycarbonate resin having high mechanical strength.

When the lid 5 once pulled out is returned, the lid 5 is inserted between the uppermost sheet film unit 4a and the next sheet film unit 4b. Indicates two sheet film units 4
a and 4b. If the resistance generated at this time is strong, the camera will vibrate and cause poor focus. Therefore, it is desirable to add silicon for reducing the sliding resistance to the polycarbonate resin. However, when the addition amount of silicon is large, the sliding resistance is reduced, but the extrusion screw and the material slip during injection molding, and the molding becomes unstable, and the molding dimensions vary. Then, the relationship between the amount of silicon added, operability (operating resistance), and moldability was tested, and the following Table 1 was obtained. As silicon, for example, silicon oil (KF96H, dimethylpolysiloxane) manufactured by Shin-Etsu Chemical Co., Ltd. is used. The symbols 符号, ○, ●, Δ, and × in Table 1 indicate “excellent”, “good”, “practical”, “improved”,
Each evaluation of "impractical" is shown.

[0014]

[Table 1]

According to Table 1, the amount of silicon added ranges from 0.5% to 0.5% at which both the operability and the moldability are satisfied in a well-balanced manner.
It can be seen that the range is preferably 2.0%. Particularly preferably, the range is 0.7% to 1.3%, and in the present embodiment, the range is 1.0%.

Further, the lid 5 is required to have sufficient bending strength so as not to be deformed during the push-pull operation. When returning the lid 5 once pulled out in preparation for photographing, the lid 5
Is inserted between the uppermost sheet film unit 4a and the next sheet film unit 4b, the lid 5 needs to be thin, and the injection molding material is required to have good fluidity.

Therefore, the polycarbonate resin containing silicon used for the lid 5 of this embodiment has a tensile strength of 550.
kg / cm ² or more, the flexural modulus 20000 kg / cm ² or more and a melt flow index was adopted as the physical properties of 5g / 10min ~20g / 10min.

The masterbatch used as the molding material for the lid 5 of the present embodiment has the composition shown in Table 2 below.

[0019]

[Table 2]

At the time of injection molding of the lid 5, the above-mentioned master batch is added to a polycarbonate resin as a base resin to adjust the silicon concentration to 1.0%. Then, using the injection molding material whose silicon concentration has been adjusted, injection molding is performed, for example, under the conditions shown in Table 3 below. The molding machine is FS-180 / 355 manufactured by Nissei Plastic Industry.
SE type (trade name) was used.

[0021]

[Table 3]

Further, in the present embodiment, in order to reduce the sliding resistance between the pack body 3 and the sheet film unit 4 and the lid 5, silicon is used not only for the lid 5 but also for the injection molding material of the pack body 3. Was added. The relationship between the amount of silicon added to the pack body 3 and the operability (operating resistance) and moldability was tested, and the following Table 4 was obtained. The symbols ◎, ○, ●, Δ, and × in Table 4 indicate the evaluations of “excellent”, “good”, “practical”, “improved”, and “impractical”, respectively. I have.

[0023]

[Table 4]

According to Table 4, when silicon is added to the injection molding material of the pack body 3, the amount of silicon added is 0.5%, which satisfies both operability and moldability in a well-balanced manner.
It is understood that it is better to set the range to 2.0%. Also,
Particularly preferably, the range is 1.0% to 1.8%, and in the present embodiment, it is 1.5%. Therefore, the masterbatch used as the injection molding material for the pack body 3 had the composition shown in Table 5 below.

[0025]

[Table 5]

The master batch is added to a polycarbonate resin as a base resin, and the final silicon concentration of the injection molding material is adjusted to 1.5%. Table 6 below
Injection molding was carried out under the conditions shown below. The molding machine used was FS-180 / 355SE (trade name) manufactured by Nissei Plastic Industry.

[0027]

[Table 6]

A pressure plate spring 15 for urging the sheet film unit 4 toward the opening 3a is provided on the bottom surface of the film storage chamber 3b in which the sheet film units 4 are stacked and stored. Also, on the handle 5a side, a counter storage room 3 is provided.
c is provided therein, and a counter display plate 18 is provided therein. A V-shaped groove 20 is formed between the film storage chamber 3b of the pack body 3 and the counter storage chamber 3c,
Here, the telemping member 21 is ultrasonically welded.

Inside the rear end of the pack body 3, a partition plate 22 for regulating the end position of the sheet film unit 4 is provided.
Are provided with a gap between the film storage chamber 3b and the bottom surface 23. This gap serves as a collecting port 24 for receiving the exposed sheet film unit 4.

As shown in FIG. 1, a pack holder 10 for loading and using the sheet film pack 1 constructed as described above includes a holder main body 10a, a lid 51 rotatably attached to the main body 10a, An inner frame 52 slidably mounted in the main body 10a. On the lid 51,
Exposure opening 5 smaller in size than sheet film unit 4
3 are provided. The back surface of the lid 51 is a receiving surface 54 for receiving the upper surface of the sheet film unit 4 and positioning the sheet film unit 4 at the exposure position.

In the longitudinal direction of the receiving surface 54, a pair of grooves 54
a is formed, and a total of four leaf springs 56 each having one end fixed to the bottom surface of the groove 54a are provided. The leaf spring 56 presses the pack body 3 downward in the figure when the sheet film pack 1 is loaded into the pack holder 10 and the lid 51 is closed. Further, the leaf spring 56 presses the exposed sheet film unit 4 from above to move it to the bottom side in the holder main body 10a.

In the vicinity of the hinge of the lid 51, a protruding ridge portion 57 which engages with the groove 2a of the cap member 2 to lock the cap member 2 in the pack holder 10 when the sheet film pack 1 is loaded, and a claw member 12 The projections 12c, 12d (see FIG. 2) are pushed down to engage the claws 12a, 12b with the engaging holes 5 of the lid 5.
A pair of protrusions 58a and 58b that are detached from c and 5d are formed. Further, the exposure opening 5 is formed on the inner wall surface of the lid 51.
In the vicinity of the short side of 3, a telemping member 59 for preventing external light from entering through a gap between the inner wall surface of the lid 51 and the lid 5 is fixed.

A box 62 provided on the front end side of the middle frame 52,
63, the slide movement of the middle frame 52 with the holder body 10a is controlled, and the counter display plate 18
And a mechanism for stepping forward. The box 62,
Claw portions 64 protruding from openings formed in the upper wall of
Numeral 65 engages with the locking holes 5c and 5d when the opening 3a is fully opened, and regulates the range in which the lid 5 can be pulled out.

On the front surface of the pack holder 10, as shown in FIG.
2 are formed. Reference numeral 75 denotes a telemping member that prevents external light from shining through a gap between the sliding contact surface on which the middle frame 52 slides and the inner wall surface of the holder body 10a.

When the sheet film pack 1 is loaded into the pack holder 10 and the cover 51 is closed, the ridges 57 are engaged with the grooves 2c, and the cap member 2 is connected to the holder 10a and the cover 51.
Held between. Then, the projections 12c and 12d are pushed down by the projections 58a and 58b, and the claw member 12 is moved downward.
The lock of the lid 5 is released because it is removed from c and 5d.

When the pack holder 10 is mounted on the exposure frame 72 of the large format camera 71 and the lid 5 is pulled out to the full, the claws 64 and 65 are engaged with the locking holes 5c and 5d, and the pack body 3 It is stopped at the position shown in FIG. 4 where the opening 3a is completely opened. When the pull-out operation of the lid 5 is performed quickly, a large force is applied to the edges of the locking holes 5c and 5d. However, as described above, the lid is formed by using an injection-molded material having sufficient mechanical strength. 5 is formed, so that the locking hole 5
The edges of c and 5d are not deformed or chipped.

When the opening 3a of the pack body 3 is completely opened, the first sheet film unit 4a is pushed up by the pressure plate spring 15. At this time, the sheet film unit 4a is pressed to the back side by the leaf spring 56, but since the pressing force is smaller than the pressing force of the pressure plate spring 15, the sheet film unit 4a is
And is pressed against the receiving surface 54 of the pack holder 10. At this time, the middle frame 52 is locked to the holder main body 10a by the latch mechanism incorporated in the box portion 52, and the middle frame 52 does not slide when the pulling-out operation of the lid 5 is performed.

When the lid 5 is returned to the original position,
As shown in FIG. 5, the lid 5 is inserted between the first sheet film unit 4a and the second sheet film unit 4b. At this time, frictional force is generated between the lid 5 and the two sheet film units 4a and 4b. However, since the lid 5 is made of the injection molding material containing an appropriate amount of silicon as described above, the frictional force is increased. Is reduced, and the lid 5 can be reliably returned to the original position with a small operating resistance. Then, the flatness of the sheet film unit 4a at the exposure position is ensured. Further, the lid 5 is locked to the pack body 3 by a latch mechanism incorporated in the box portion 62,
The engagement between the holder main body 10a and the middle frame 52 is released. Further, a display indicating the completion of the shooting preparation is displayed on the window of the arc-shaped projection 78 seen from the photographer side. By opening and closing the shutter of the large format camera in this state, the first sheet film unit 4a is exposed.

After the first photographing operation is completed, the user grasps the handle 5a and pulls it, as shown in FIG. 6, leaving only the cap member 2 behind the pack holder 10 and the middle frame 52 and the sheet film pack 1 as shown in FIG. Are pulled out of the pack holder 10 integrally. At this time, the edge portion 54 of the receiving surface 54
b, the exposed first sheet film unit 4a is locked at the same position, so that the sheet film unit 4a is moved from the pack body 3 through the gap between the upper surface of the lid 5 and the receiving surface 54. Get out.

The sheet film unit 4a discharged from the pack body 3 is moved by the leaf spring 56 to the holder body 10a.
And the front end 4p of the sheet film unit 4a rests on the unit receiving surface 25, and the rear end 4q rests on the L-shaped sheath receiving member 31 provided integrally with the cap member 2. State. Then, the middle frame restricting means (not shown) operates, so that the middle frame 52 cannot be pulled out any further. At this time, since the lid 5 closes the opening 3a of the pack body 3, even if the sheet film pack 1 is pulled out from the pack holder 10, external light does not reach the sheet film unit 4 in the pack body 3. Absent.

Next, the sheet film pack 1 is inserted into the middle frame 52.
When the sheet film unit 4a is inserted into the holder main body 10a, the rear end 4q of the sheet film unit 4a is
Then, the sheet film unit 4a enters the pack body 3 through the collection port 24, rides on the pressure plate spring 15, and is inserted into the lowermost layer of the unexposed sheet film unit 4.

When the sheet film pack 1 is completely inserted into the holder main body 10a together with the middle frame 52 in this manner, the counter feed pawl incorporated in the box portion 62 passes through the opening formed in the pack main body 3a. The counter display plate 18 is engaged with the counter display plate 18 to rotate and advance the counter display plate 18 by one scale. Then, the second sheet film unit 4b
Is in a state similar to that of FIG. Hereinafter, by repeating the same operation, the photographing can be performed one after another.

[0043]

As described in detail above, according to the sheet film pack of the present invention, since the lid is injection-molded with a polycarbonate resin, the mechanical strength of the lid is improved, and the lid is vigorously pulled in and out. Even so, it is possible to prevent the edge of the locking hole from being damaged or deformed. Also, since 0.5% to 2.0% of silicon is added to the polycarbonate resin, the operating resistance of the lid is reduced, and the lid can be pulled out and inserted with a light force, and the camera is pulled. It is possible to prevent the image from being out of focus due to the vibration caused by the operation of removing and inserting the lid. Further, the polycarbonate resin with the addition of silicon, a tensile strength of 550 kg / cm ² or more, the flexural modulus 20000 kg / cm ² or more, and since the melt flow index was physical property values of 5g / 10min ~20g / 10min, the引蓋Improvement of mechanical strength, reduction of operating resistance, and improvement of formability can all be satisfied at the same time.

[Brief description of the drawings]

FIG. 1 is an external view of a sheet film pack and a pack holder of the present invention.

FIG. 2 is a cross-sectional view showing a structure of a sheet film pack.

FIG. 3 is a cross-sectional view showing a pack holder and a sheet film pack in an initial state attached to a camera.

FIG. 4 is a cross-sectional view showing a pack holder and a sheet film pack from which the lid has been pulled out from the state shown in FIG. 3;

FIG. 5 is a cross-sectional view showing a pack holder and a sheet film pack during photographing.

FIG. 6 is a sectional view showing a pack holder and a sheet film pack in a state where a slide frame is pulled out after photographing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet film pack 2 Cap member 3 Pack body 4 Sheet film unit 5 Pull lid 5c, 5d Lock hole

Claims (2)

[Claims] 1. A pack body for stacking and storing a plurality of sheet film units in which one sheet film is held in a planar shape by a sheath, and a topmost sheet film unit formed on a front wall of the pack body. And a lid slidably provided in the main body of the pack and having a lid for opening and closing the opening, wherein the lid is made of polycarbonate to which 0.5% to 2.0% of silicon is added. A sheet film pack characterized by injection molding using a resin. 2. The polycarbonate resin to which silicon is added has a tensile strength of 550 kg / cm ² or more and a flexural modulus of 2
2. The sheet film pack according to claim 1, wherein the sheet film pack has a physical property value of 0000 kg / cm ² or more and a melt flow index of 5 g / 10 min to 20 g / 10 min.