GB2227101A - Lens-fitted photographic film package - Google Patents

Abstract

A lens-fitted photographic film package comprises a light-tight film case having an exposure effective member, a taking lens, a tolled film 21 in a film roll receiving chamber 71 disposed on one side of an exposure frame in the light-tight case, and a removable film container having a film winding spool therein disposed on the other side of the exposure frame in the light-tight film case, the chamber 71 having a film end retaining member 72 which maintains an end portion 23a of the film away from the inner surface of the chamber adjacent to the exposure frame. <IMAGE>

Description

LENS-FITTED PHOTOGRAPHIC FILM PACKAGE The present invention relates to a lens-fitted photographic film package which has a taking lens attached to a light-tight film case, an exposure member with its associates elements incorporated in the light-tight film case, and a photographic film previously loaded in the photographic film case as an integral whole.

A lens-fitted photographic film package has been placed on the market on an industrial scale by the applicant of this application. This lens-fitted photographic film package comprises a film case fitted with a taking lens, a simple exposure mechanism which includes a film winding mechanism and a snutter mechanism with their associated elements incorporated in the film case, and a 110-size cartridge film previously packaged in the film case. As the lens-fitted photographic film package has no conventional back cover for allowing loading and unloading a film and no complex exposure control mechanism, a considerably low manufacturing cost has been realized. The lensfitted photographic film package, after the exposure of all frames of the film, is forwarded to a photo-shop or photo laboratory without removing the film.There, the exposed film is removed by breaking open the film package and then developed to make prints therefrom while the film package without film is scrapped. The prints together with the developed film are returned to the customer. The lens-fitted single-use film package makes it easy to take pictures because of no requirement of film loading and unloading. As is well known in the art, the 110-size film cartridge has a roll of 110-size film strip contained light-tightly therein. The film package can be assembled by fitting the film cartridge to an exposure chamber formed inside the lens-fitted film case.Due to the incorporation of cartridge film, not only the assembling of the film package but also the removal of the film cartridge from the film package can be made in a daylight room without fogging the film in the cartridge.

However, it is hard to make an enlarged print with a favorable image quality from the 110-size film. For improving image quality, it has been proposed to provide a lens-fitted film package including a 135-size roll film whose image size is 36 x 24 mm. In the case of incorporating the 135mm-size roll film defined by International Standardization Organization ( ISO code 1007: 1979 edition ) in such a lens-fitted film package, it is preferred to encase a rolled film and an empty film container or patrone in a light-tight film case of the film package, the rolled film being wound up in the patrone by one frame every exposure. Due to the provision of the empty patrone in the light-tight film case of the film package, when the exposure of all frames of the film is completed, the film is fully in the patrone.Therefore, the patrone can be taken out very easily, namely without any requirement of film rewinding operation. The exposed film is removed from the patrone and handled in the same manner as conventional 135-size film for development and processing while the film case is scrapped.

In the case of fastening the unexposed roll film round a spool in a film receiving chamber of the light-tight film case, a serious problem lying behind such a lens-fitted film package is that the spool disposed in the film receiving chamber is required to rotate to allow an advancement of film after the exposure of each frane of the film. To satisfy this requirement, the lens-fitted photographic film package becomes complicated in structure. For structural simplicity, it is desirable not to provide any spool in the film receiving chamber of the light-tight film case.

Viewed from one aspect the :present invention provides a lens-fitted photographic film package having at least means for effecting an exposure, and a taking lens, which comprises a light-tight film case, a film in the form of a roll light-tightly contained in said light-tight film case, and a film container in which said film is wound after being exposed, wherein said light-tight film case comprises at least a front case section formed with an open sided film roll receiving chamber and a rear film case section which light-tightly covers said film in said film roll receiving chamber, said open side of said film roll receiving chamber being of a width smaller than the inside width of said film roll receiving chamber.

By providing the film roll receiving chamber with a reduced width of the lengthwise opening, the rolled film can be loaded in the film roll receiving chamber without loosening and bulging out of the film roll receiving chamber, resulting in a smooth film advancement and a prevention of getting scratch marks.

Viewed from another aspect the invention provides a lens-fitted photographic film package having at least means for effecting an exposure, and a taking lens, which comprises a light-tight film case, a film in the form of a roll light-tightly contained in said light-tight film case, and a film container in which said film is wound after being exposed, wherein said light-tight film case has a film roll receiving chamber which light-tightly receives said film therein, said film roll receiving chamber havinh upper and lower rims formed on an inner surface thereof for supporting an outermost convolution of said film in the form of a roll at its upper and lower sides.

As the said rims contact with upper and lower margins of the film, the film receives a greatly reduced frictional force from an inner surface of the film roll receiving chamber.

Therefore, the film can be advanced smoothly and prevented from getting scratch marks on image frames thereof.

Viewed from a further aspect the invention provides a lens-fitted photographic film package comprising at least a light-tight film case incorporating exposure effecting means and a taking lens, a film in the form of a roll in a film roll receiving chamber formed adjacent to and on one side of an exposure frame of said light-tight film case, which film is arranged to be advanced from said one side to the other side frame by frame after exposure and is wound in a roll on said other side, wherein said film roll receiving chamber has a film end retaining member which maintains an end portion of said film away from an inner surface of said film roll receiving chamber adjacent to said exposure frame.

As the said film end retaining member engages the inner end of the film roll, the end portion of the film roll is never rendered folded or bent, thus being prevented from being bitten by a film exit slit adjacent to the film roll receiving chamber when the end of the film is withdrawn out of the film roll receiving chamber.

Viewed from yet another aspect the invention provides a lens-fitted photographic film package having at least exposure effecting means and a taking lens, which comprises a light-tight film case, a film which is formed in a roll and contained in a film roll chamber of said light-tight film case, and a film container received in said light-tight film case into which said film, after exposure, is advanced and would frame by frame, wherein means is provided to exert a frictional force on said film as said film is advanced.

Some embodiments of the invention wi1! now l,e described by way of example and with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a lens-fitted photographic film package of the present invention; Figure 2 is an exploded perspective view of a lensfitted photographic film package of a first embodiraent according to the present invention; Figure 3 is a cross sectional view of the lens-fitted photographic film package of Figure 1; Figure 4 is a cross sectional view of a conventional lens-fitted photographic film package showing the shortcoming of prior art; Figures 5(A), (B) and (C) are cross sectional views showing partially the lens-fitted photographic film package of Fig. 2 in which the film roll receiving chamber is modified;; Figure 6 is an illustration of another embodiment of a lens-fitted photographic film package according to the present invention; Figure 7 is a elevational sectional view showing the film roll receiving chamber of the lens-fitted-photographic film package of Fig. 6; Figures 8(A), (B) and (C) are cross sectional views showing partially a film roll receiving chamber of a conventional lens-fitted photographic film package; Figure 9 is a cross sectional view similar to Fig. 3 showing the lens-fitted photographic film package of another embodiment accordinq to tile present invention; Figures 10 (A) and (B) are explanatory vies showing the film roll receiving chamber of the lens-fitted photographic film package of Fig. 9;; Figures 11(A) and (B) are explanatory illustrations showing a modification of the film roll receiving chamber of Fig. 9; Figures 12(A) and (B) are explanatory illustrations showing a further modification of the film roll receiving chamber of Fig. 9; Figure 13 is a cross sectional view, similar to Fig. 3, of the lens-fitted photographic film package of a further embodiment according to the present invention; Figure 14 is a cross sectional view, similar to Fig. 13, showing a modification of the lens-fitted photographic film package of Figure 13; and Figure 15 is a cross sectional view, similar to Fig. 13, showing another modification of the lens-fitted photographic film package of Figure 13.

Referring now to Figs. 1 and 2, shown therein is a lensfitted photographic film package ( which is hereinafter referred to as a film package for simplicity ) embodying the present invention. The film package 1 comprises a front case section 2 and a rear case section 3 which are assembled to one body to form a generally rectangular box-shaped light-tight film case.

The front case section 2 is provided with a taking lens 4, a viewfinder window 5, and a shutter actuating member 6 in its outer walls. In the film package 1, there are necessary elements such as a simple exposure control, a shutter mechanism, a film advancing mechanism, and the like incorporated therein. The rear case section 3 is fixed to the front case section 2 in any well known manner, for example by means of an ultrasonic welding, so as not to be separated by the user. The film package 1 is preferably encased tightly in an outer case which is formed with several openings for exposing the taking lens 4, finder window 5, and shutter actuating member 6, and is made of printable cardboard or printable plastic sheet.

In Fig. 2 showing the film package 1 disassembled into two case sections, the front case section 2 has an opening 2B extending between its back and bottom. The rear case section 3 has a substantially L-shaped configuration to complementarily close the opening 2B of the front case section 2 so as to provide a box-shaped light-tight film case. Inside the front case section 2, there are a film roll receiving chamber 11 awing a bottom opening 11a and a film patrone receiving chamber 12 having a bottom opening 12a which are disposed on both sides of an exposure frame 1 0. Projecting downwardly from the top wall of the film patrone receiving chamber 12 is a fork 14 which is adapted to cooperate directly with a film advancing knob 8 and to rotate in the clockwise direction as viewed in Fig.2.The exposure frame 10 is formed with film guiding and supporting rails 15 on upper and lower sides thereof. In the upper rail 15, there is a sprocket wheel 16 partially projecting out of an outer surface of the upper rail 15.

As is shown in Fig. 3, the film roll receiving chamber 11 is an open sided cylindrical chamber having a side opening whose width W is smaller than a diameter D of the outermost convolution of the film roll 23 which depends on the maximum width of the film roll receiving chamber 11. This width W of the side opening is confined by a bulge portion 2a and an inner wall of the front case section 2. On the other hand, inside the rear case section 3, there is a back-up portion 30 shape complementarily to the curved surface of the film guiding and supporting rails 15 of the exposure frame 10 for supporting the film from its back so as to hold it in a focal plane of the taking lens 4.In addition, the back-up portion 30, when the rear case section 3 is fitted to the front case section 2, closes the side opening of the film roll receiving chamber 11 to form a complete film roll receiving chamber 11 leaving a film exit slit 13. There is also a raised portion 32 ( see Fig. 2 formed inside the bottom wall of the rear case section 3 which closes the bottom opening lla of the film roll receiving chamber 11 and supports the lower edges of the convolutions of the film roll 23. From the economical point of view, it is preferable to use a plastic single lens for the taking lens 4. Although the plastic single lens produces a distortion, nevertheless the curved form of the film guiding and supporting rails 15 is helpful to avoid the influence of distortion.

Upon assembling the film package 1, a roll 23 of 135size film 21 and an empty film patrone 20 in which the film 21 at its one end is retained by a spool 28 ( see Fig. 3 ) in the film patrone 20 are put in the receiving chambers 11, 12, respectively, prior to assembling the two case sections 2 and 3.

This film 21 is of the type having a 36 x 24mm image frame which is defined as 135-size film by ISO-1007 ( International Standardization Organization: 1979 edition ).

The above described film loading operation is, in this embodiment, performed by the aid of a film loading jig which is shown by a double dotted line in Fig. 2. In greater detail, the unexposed film 21 withdrawn out of the film patrone 20 is wound around a cylindrical spool member 22 of the loading jig as a film roll 23 in many convolutions. While, the film patrone 20 is held by a gripping arm 25 of the loading jig and part 26 of the film 21 extending between the film roll 23 and the film patrone 20 is supported by a plate member 27 of the loading jig in such a way as to be slightly lifted up to curve.

The film patrone 20 and the film 21 thus held by the loading jig can be inserted into the respective receiving chambers 11 and 12 through respective bottom openings 71a and 12a by moving the loading jig toward the front case section 2 until the top of a spool 28 ( see Fiy. 3 ) of the film patrone 20 is brought into engagement with the fork 1 4. During this film loading operation, since the part 26 of the film 21 is lifted up, an upper edge of the part 26 is by no means caught by teeth of the sprocket wheel 16.

After having loaded the film roll 23 and the film patrone 20 in the above described manner, the gripping arm 25 unclamps the patrone 20 and the cylindrical spool member 22 is resiliently deformed te release the film 21. The deformation of the cylindrical spool member 22 is allowed due to the provision of a slit 22a which nips one end of the film 21. Then the loading jig is withdrawn leaving the film roll 23 and the film patrone 20 in the respective receiving chambers 11 and 12.

Although the rolled film 23 is liable to loosen due to its own curling effect or stiffness, the outermost convolution of the film roll 23 is restricted by the bulged portion 2a extending along the open sided film roll receiving chamber 11 to prevent the film roll 23 from loosening to project out of the film roll receiving chamber 11. Then the rear case section 3 is fixed and welded to the front case section 2 to enclose the film 21 lighttightly in the photographic film case.

In using the film package 1 thus assembled, when the shutter actuating member 6 is operated, a shutter 35 is caused to open and close so as to make an exposure for the first frame of the film 21 placed over the exposure frame 10. After this exposure, the film advancing knob 8 is operated to rotate the fork 14, thereby rotating the spool 28 of the patrone 20 to ithdraw and wind the film 21 by one frame, namely to take up the exposed part of the film 21 in the film patrone 20. On the other hand, another frame of the film 21 adjacent to the exposed frame is placed over the exposure frame 10 while rotating the sprocket wheel 16.When the sprocket 16 makes a predetermined number of revolutions, the film advancing mechanism and the shutter actuating mechanism with its associated elements are self-cocked in a well known manner to those skilled in the art so as to complete a necessary operation of the film package 1 for the next exposure.

Upon this one frame film advancement, the film roll 23 is withdrawn, being rotated as a whole in the counterclockwise direction as viewed in Fig. 3 in the film roll receiving chamber 11. For a better understanding of the present invention, a prior art lens-fitted photographic film package 1' will be explained with reference to Fig. 4. The prior lens-fitted photographic film package 1' is provided with a roll film receiving chamber 11' of which the width of the side opening is equal to a maximum diameter of the film roll receiving chamber 11'. Therefore, when the film roll 23 is placed in the film roll receiving chamber 11' by means of the loading jig, the film roll 23 will loosen and partially bulge out of the film roll receiving chamber 11' before attaching the rear case section 3.

For this reason, when the rear case section 3 is attached to the front case section 2, the roll film 23 is depressed and deformed. In such prior art film package 1', when the film 21 is withdrawn from the film roll receiving chamber 11', between the outermost convolution of the film roll 23 and the inner surface of the roll film receiving chamber 11' there occurs a relatively large friction force. The film advancing knob 8 becomes heavy to be operated. If the film advancing knob 8 is forced into operation so as to advance the film 21 against the relatively large friction force, the film roll 23 will get scratch marks on the surfaces of the outermost convolution of the film roll 23 and part of the outermost convolution of the film roll 23 will be bitten by film exit slit 13'.

It is obvious on comparing the film package 1 of the present embodiment with the prior one that, since the reduced width of the side opening of the open sided film roll receiving chamber 11 of the film package 1 according to the present embodiment 2an prevent the film roll 23 in the film roll receiving chamber 11 from bulging out before attaching the rear case section 3 to the front case section 2, the back-up portion 30 of the rear case section 3 does not depress and deform the film roll 23 when the rear case section 3 is attached to the front case section 2.Therefore, in the film package 1 of the present embodiment,the film roll 23 is maintained substantially circular in the film roll receiving chamber 11 so that the film advancing knob 8 can be operated smoothly and that the film roll 23 in the film receiving chamber 11 can be prevented from getting scratch marks on the surface of the outermost convolution thereof.

As the exposure is repeated in the same manner as described above, the film 21 is wound up in the patrone 20 frame by frame. After the exposure of all frames of the film 21, the film package is forwarded to a photo-shop without removing the exposed film 21. There, the rear case section 3 is detached from the front case section 2 by the aid of, for example, an dismantling jig and then the film patrone 20 with the exposed film 21 contained therein is taken out. The film patrone 20 is handled in the same manner as conventional so as to remove the exposed film 21 in order to process it for development and printing.

It is desirable to form an openable portion 40 in a bottom wall of the rear case section 3. This openable portion 40 is defined by a circular groove 37 formed in an inner surface of the bottom wall of the rear case section 3 and is easily breakable along the groove 37. The openable portion 40 is broken from the rear case section 3 to form an opening in the bottom wall of the rear case section 3 so as to allow the film patrone 20 to be taken out longitudinally. For an easy breaking of the openable portion 40, there is a tab 38 received in a recess 41 formed in the bottom wall of the rear case section 3.When the tub 38 is pulled up, the openable portion 40 of the bottom wall of the rear case section 3 is easily broken and torn off along the groove 37, providing an opening through which the film patrone 20 can be taken out without detaching the rear case section 3 from the front case section 2. The forming of the opening in the light-tight case of the film package 1 prevents the light-tight film case being reused. Therefore, it will be generally prevented to refill another film in the used lighttight film case in order to create a film package which is unassured for its accurate operation.

Fig. 5 shows several variations of the film roll receiving chamber 11 of the film package 1 shown in Figs. 1 to 3. A film roll receiving chamber 11 shown in Fig. 5(A) has a main chamber portion having a generally rectangular cross section. The main chamber portion is provided with the bulge portion 2a which defines a reduced width side opening in combination with a bulge 3a formed integrally with the back-up portion 30 of the rear case section 3.

In any film package described above, if the film 21 is withdrawn rapidly or at a high rate of film advancement, the film roll 23 is possibly deformed. As a result, the film roll 23 will be bittenby the film exit slot 1 3 so as to get scratch marks on the surface of the outermost convolution thereof. For preventing such a deformation of the film roll 23, it is desirable to provide a brake shoe 3b adjacent to and after the film exit slot 13 as is shown in Fig. 5(B).

As is shown in Fig. 5(C), the bulge portion 2a of the previous embodiments shown in Figs. 5(A) and 5(B) may be replaced by a separately provided bulge member 40 which is fixed to the inner surface of the film roll receiving chamber 11.

Referring now to Figs. 6 and 7 showing another embodiment of the present invention, a film roll receiving chamber 51 is provided with semi-circular rims 51b at its top and bottom. en the film roll 23 is placed in a film roll receiving chamber 51 of the front case section 2 in the same way as described in connection with the previous embodiment, the film roll 23 loosens until the outermost convolution of the film roll 23 is engaged by the rims 51b. Therefore, the outermost convolution of the film 21 is maintained spaced from the inner surface 51c of the film roll receiving chamber 51. Due to the provision of the rims 51b, the friction force exerted on the outermost convolution of the film roll 23 is greatly reduced upon the film advancement after exposure, resulting in a smooth and light film advancement operation.Furthermore, because of the spacing of the outermost convolution of the film roll 21 from the inner surface 51c of the film roll receiving chamber 51, the film 21 is prevented from getting scratch is thereon.

Because the film roll 23, as is previously described in connection with Fig. 2, or Fig. 6, is formed by the aid of the film loading jig, in particular the cylindrical spool member 22 having the slit 22a by which one end of the film 21 is nipped, the end of the film 21 is bent and is usually unrestored.

Accordingly, the unrestored bent portion of the film 21 is bitten by the film exit slot 13. In more detail, since the stiffness of film is lost with time, the film roll 23 contained in the film roll receiving chamber 11, 51 for a while does not loosen any more. For this reason, the last few convolutions of the film roll 23 become smaller in diameter and are drawn toward the film exit slot 13 as is shown in Fig. 8(A) with the advancement of the film 21 because the stiffness of the film 21 is lost in time. When the last convolution of the roll filn 23 including the unrestored bent end portion 23a reaches the film exit slot 13 as is shown in Fig. 8(B), in particular as is shown in Fig.

8(C), the unrestored bent end portion 23a results in being bitten by the film exit slot 13.

Referring to Figs. 9 and 10 showing another embodiment of the present invention, for preventing the unrestored bent end portion 23a from being bitten by the film exit slot 13, there is provided in the film roll receiving chamber 61 of the film package 1 a cylindrical hollow tube 63 extending downwardly from the top of the film roll receiving chamber 61.

Upon placing the roll film 23 in the film roll receiving chamber 61 for assembling the film package 1, the film roll 23 is put around the cylindrical tube 63. As the cylindrical tube 63 can serve to maintain the unrestored bent end portion 23a of the film roll 23 far away from the film exit slot 13 as shown in Fig. 10(B), the unrestored bent end portion 23a is never bitten by the film exit slot 13.

It is to be noted that the cylindrical tube 63 may be replaced with an expandable hollow tube member made of a resilient material. This expandable hollow tube member 72, as is shown inFig. 11, is adapted to press the film roll 23 against the inner surface of the film roll receiving chamber 71. As the film 21 is advanced frame by frame and wound in the film container 20, the roll film 23 is reduced in diameter. When almost all of the film 21 is wound leaving only the end portion 23a of the film roll 23 in the film roll receiving chamber 71, the expandable hollow tube member 72 fully expands as is shown by chained line in Fig. 11(B) to support the end portion 23a of the fi-lin roll 23 unfolded, namely substantially straight.

Therefore, the end portion 23a of the film roll 23 is prevented from being bitten by the film exit slot 13.

Fig. 12 shows a resilient supporting plate 75 by which the cylindrical tube 63 of Fig. 10 or the expandable cylindrical hollow tube 72 is replaced. The resilient supporting plate 75 is attached to the inner wall of the film roll receiving chamber 74 by means of set screws and has a substantially semi-circular cross section so as to support the film roll 23 therein. The resilient supporting plate 75 is forced by its own resiliency to contract and maintain its one edge 76 apart from the edge of the exposure frame 10. It is desirable to make the one edge round outwardly so as to prevent the film 21 from getting scratch marks when the film 21 is advanced.

When many convolutions of the film roll 23 are in the film roll receiving chamber 74 by being supported by the resilient supporting plate 75, the supporting plate is expanded to move the one edge 76 outwardly downwardly by the film roll 23 as is shown in Fig. 12(B). As the number of convolutions of the film roll 23 is reduced, the one edge 76 is permitted to displace inwardly in a direction shown by an arrow X in Fig.

12(B) so as to maintain the film roll 23 apart from the edge of the exposure frame 10. In such a way, the resilient supporting plate 75 can prevent the unrestored bent end portion 23a of the film roll 23 from being bitten by the film exit slit 13. The resilient supporting plate 75 may be attached to the inner wall of the film roll receiving chamber 74 at its bottom to make both edges thereof free. Although the resilient supporting member 75 is shown in Fig. 12 as having substantially the same longitudinal width as the film 21, it is permissible to have a width narrower tan the width of the film 21. The resilient supporting plate 75 may be punched out to form an opening 77 shown by a double dotted line in Fig. 12(A). It is preferred to make the resilient supporting plate of, for example, thin stainless steel plate, or plastic materials having no photographically bad effects.

In any above described embodiment of the lens-fitted photographic film package, for economical reasons, there is provided neither a pressure plate between the film roll receiving chamber and the film patrone receiving chamber nor a film spool in the film roll receiving chamber. For this reason, the film roll 23 and/or the film 21 rolled in the film patrone 21 is apt to get loose. If the film roll 23 and/or the film 21 rolled in the film patrone 20 gets loose, the film 21 cannot be advanced stably, namely by a restrictly controlled distance every time, resulting in unequal margins between frames. For avoiding such unequal margins, -the film package 1 may be provided with a friction applying member.As is shown in Fig. 13, there is provided a projection 82 as a friction applying member which abuts against the film patrone 20 to incline the film slot 20a of the film patrone 20 downwardly with respect to a film passage 80 along which the film 21 will ordinarily pass. Due to the provision of the projection 82, the film 21 adjacent to the film slot 20a of the film patrone 20 is forced to partially curve.

Therefore, a friction force is exerted on the film 21 when the film 21 is advanced.

Alternatively, the friction applying member may be disposed to abut the patrone 20 so as to incline the film slot 20a of the patrone upwardly as is shown at 84 in Fig. 14. It is apparent that the projection 84 exerts a friction force on the film 20 in the same manner as the projection 82 of Fig. 13.

According to experimental results, the lack of a friction applying member such as the projection 82, 84, can cause differences more than 2 mm between margins between frames when a film having 24 available frames is advanced with a film advancing torque of about 320 - 400 gcm. Used for the experiments is a lens-fitted photographic film package in which the width of the film passage 80 and the minimum inner diameter of the film roll receiving chamber 11 are about 0.2 mm and 20 mm, respectively. The film advancing torque depends on the number of convolutions of the film roll 23 remaining in the film roll receiving chamber 11 and on the number of frames of a film incorporated in the film package. By contrast, the provision of the friction applying member 82, 84 contributes greatly to reduce the difference between margins.If the film advancing torque reaches more than about 800 gcm, the film advancement operation becomes quite heavy and unfavorable for the lens-fitted photographic film package. According to actual usages of the film package, the friction force caused by the friction applying member 82, 84 which is suitable for a good feeling of operation and substantially equal margins is between 480 and 640 gcm in film advancing torque. If the film advancing torque becomes less than 480 gcm, the friction force caused by the friction applying member does not serve effectively to reduce the differences of margins between frames. In the above experiments, each torque is measured based on a force applied to the outer periphery of the film advancing knob 8.

It is to be understood that each projection 82, 8t as the friction applying member may be disposed before and adjacent to the film exit slit 13 as is shown in Fig. 15. Although the projection 82, 84 shown in Figs. 13 and 14 is formed integrally with one of the front and rear case sections 2 and 3, it is permissible to provide a resiliently supported projection or a resilient projection. In any case, the friction applying member can prevent the film 21 from getting loose.

It willl thus be seen that the present invention, at least in its preferred forms, provides a lens-fitted photographic film package which makes it possible to reduce the frictional force exerted on a film rolled in a film receiving chamber of the lens-fitted photographic film package; and furthermore provides a lens-fitted photographic film package in which a film can be advanced smoothly; and further provides a lens-fitted photographic film package in which a film is prevented from getting scratch marks on a surface thereof.

It is to be clearly understood that there are no particular features of the foregoing specification,or of any claims appended hereto, which are at present regarded as being essential to the performance of the present invention, and that any one or more of such features or combinations thereof may therefore be included in, added to, omitted from or deleted from any of such claims if and when amended during the prosecution of this application or in the filing or prosecution of any divisional application based thereon.

Claims (3)

Claims

1. A lens-fitted photographic film package comprising at least a light-tight film case incorporating e:posure effecting means and a taking lens, a film in the for;n of a roll in a filn roll receiving chamber wormed adjacent to and on one side of an exposure .rame of said light-tight film case, which film is arrangec to be advanced from said one side to the other side frame by frame after exposure and is wound in a roll on said other sides wherein said film roll receiving chamber has a fil end retaining member which maintains an end portion of said film away from an inner surface of said film roll receiving chamber adjacent to said exposure frame.

2. A lens-fitted photographic film package as claimed in claim 1, wherein said filmy end retaining mer.ber extends longitudinally in said film roll receiving chamber and said film is rolled around said film end retaining member.

3. A lens-fitted photographic film package as claimed in claim 1 or 2 ,wherein said film end retaining member is a cylindrical rotatable member.

4 A lens-fitted photographic film pac]z2ge as claimed in claim 3, wherein said cylindrical rotatable member is adapted to be resiliently expandable.