One-time use camera uncovers ingress opening for insertion tool to eject cassette when cassette closed
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Reference is made to commonly assigned copending applications Ser. No. 08/371336, now U.S. Pat No. 5,550,608, entitled APPARATUS AND METHOD FOR CLOSING LIGHT LOCK OF FILM CASSETTE AND UNLOADING CASSETTE FROM CAMERA and filed Jan. 11, 1995 in the names of David C. Smart and Thomas E. Dussinger, Ser. No. 08/590,968, entitled CAMERA WITH FILM SENSOR AND DRIVER TO INITIATE CLOSING OF CASSETTE RESPONSIVE TO RETURN OF FILMSTRIP TO CASSETTE and filed Jan. 24, 1996 in the names of David C. Smart and Douglas H. Pearson, Ser. No. 08/590,662, entitled ONE-TIME-USE CAMERA HAS DRIVER FOR CLOSING FILM CASSETTE WHICH IS REMOVED WITH CLOSED CASSETTE TO DISABLE CAMERA AFTER COMPLETED USE and filed Jan. 24, 1996 in the names of David C. Smart and Douglas H. Pearson, Ser. No. 08/590,666, entitled ONE-TIME-USE CAMERA HAS DRIVER FOR CLOSING FILM CASSETTE WHICH IS BROKEN TO DISABLE CAMERA AFTER COMPLETED USE and filed Jan. 24, 1996 in the names of David C. Smart and Douglas H. Pearson, Ser. No. 08/590,792, entitled CAMERA WITH MANUAL FILM REWIND LOCKED WHEN CASSETTE CLOSED, PREFERABLY TO POSITION FILM EXPOSED INDICATOR IN WINDOW OF CASSETTE and filed Jan. 24, 1996 in the names of David C. Smart and Thomas E. Dussinger, and Ser. No. 08/590,719, entitled ONE-TIME-USE CAMERA WITH LID FLEXED TO UNCOVER CHAMBER WHEN CASSETTE FORCIBLY EJECTED FROM CHAMBER and filed Jan. 24, 1996 in the names of David C. Smart and Ralph M. Lyon. 
     FIELD OF THE INVENTION 
     The invention relates generally to the field of photography, and in particular to cameras to be used with film cassettes. More specifically, the invention relates to a one-time-use camera that uncovers an ingress opening for an insertion tool to eject the film cassette from the camera when the cassette is closed following return of a filmstrip to the cassette. Also, the invention relates to a camera with a manual film rewind that when rotated after the filmstrip is wound into the cassette closes the cassette. 
     BACKGROUND OF THE INVENTION 
     Commonly assigned prior art U.S. Pat. No. 5,357,303, issued Oct. 18, 1994, discloses a film cassette having a light lock which is pivoted closed to prevent ambient light from entering the cassette interior and is pivoted open to permit film movement out of and into the cassette interior. An implement or tool is designed to engage the light lock to pivot it open and closed. 
     Commonly assigned prior art U.S. Pat. No. 5,231,438, issued Jul. 27, 1993, discloses a camera intended for use with a film cassette having a light lock which is pivoted closed to prevent ambient light from entering the cassette interior and is pivoted open to permit film movement out of and into the cassette interior. The camera has a release button which when manually moved in a releasing direction actuates a latching device. The latching device normally secures a door closed over a chamber holding the film cassette. However, when the latching device is actuated, it operates to pivot the light lock closed and to release the door to uncover the chamber. 
     SUMMARY OF THE INVENTION 
     A camera for use with a film cassette having a light lock movable to be closed after an exposed filmstrip is wound into the cassette, comprises a chamber for the cassette from which the cassette can be removed, and a driver movable to close the light lock before the cassette is removed from the chamber, and is characterized in that: 
     an ingress opening to the chamber is provided to admit an insertion tool into the chamber to push the cassette out of the chamber; and 
     covering means is movable relative to the ingress opening to uncover the ingress opening after the driver is moved to close the light lock, to permit the insertion tool to be moved through the ingress opening to push the cassette out of the chamber when the light lock is closed. 
     Preferably, a film wind thumbwheel is manually rotatable to wind the exposed filmstrip including a trailing film end portion into the cassette and is coupled with the driver after the trailing film end portion is wound into the cassette to allow the thumbwheel to move the driver to close the light lock when the thumbwheel is further rotated. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded partial perspective view of a camera for use with a film cassette, according to a preferred embodiment of the invention; 
     FIG. 2 is an assembled partial perspective view of the camera with the film cassette as seen from an opposite side; 
     FIGS. 3, 4, 5 and 6 are assembled partial perspective views of the camera with the film cassette, depicting operation of the camera; 
     FIGS. 7, 8, 9, 10, 11, 12, 13 and 14 are opposite end views of the film cassette, depicting operation of a visual exposure indicator (VEI); 
     FIGS. 15, 16 and 17 are assembled partial perspective views of the camera with the film cassette, depicting how the film cassette is ejected from a cassette chamber; and 
     FIG. 18 is an assembled partial perspective view of the camera with the film cassette, according to an alternate embodiment of the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The invention is disclosed as being embodied preferably in a camera. Because the features of a camera are generally known, the description which follows is directed in particular only to those elements forming part of or cooperating directly with the disclosed embodiment. It is to be understood, however, that other elements may take various forms known to a person of ordinary skill in the art. 
     Film Cassette 
     Referring now to the drawings, FIGS. 1 and 2 show a film cassette 10 similar in operation to ones disclosed in prior art U.S. Pat. No. 5,357,303, issued Oct. 18, 1994, and U.S. Pat. No. 5,231,438, issued Jul. 27, 1993. The film cassette 10 includes a cassette shell 12 that contains a flanged spool 14 on which is stored a wound unexposed/exposed filmstrip 16. A slightly elastic light lock 18 is supported within a film egress/ingress slot 20 in the cassette shell 12 to be pivoted open to permit film movement out of and back into the shell, through the slot, and to be pivoted closed to prevent ambient light from entering the shell, through the slot. 
     FIGS. 1 and 2 show the film cassette 10 from opposite sides, with the light lock 18 open and all but a trailing film end portion 22 of the filmstrip 16 wound into the cassette shell 12 after the filmstrip is exposed outside the cassette shell. FIG. 6 shows the light lock 18 pivoted completely closed after the trailing film end portion 22 is wound into the cassette shell 12. 
     The spool 14 has a coaxial drive cavity 24 accessible at a drive end 26 of the cassette shell 12 and the light lock 18 has a coaxial drive cavity 28 accessible at the same end of the cassette shell as shown in FIG. 1. A visual exposure indicator (VEI) in the form of an indicator flag 30 is rotatable coaxially with the spool 14 to be respectively positioned in four separate windows 32, 34, 36 and 38 in a VEI end 40 of the cassette shell 12 when the spool is at different predetermined angles of rotation. The VEI end 40 of the cassette shell 12 is an opposite end of the cassette shell, with respect to the drive end 26 of the cassette shell. As shown in FIGS. 7 and 8, when the spool 14 is at a predetermined acute angle of rotation 42 the indicator flag 30 is at the same angle to be positioned in the window 32, to provide a visual film-unexposed warning or indication. As shown in FIGS. 9 and 10, when the spool 14 is at a predetermined first-obtuse angle of rotation 44 the indicator flag 30 is at the same angle to be positioned in the window 34, to provide a visual film-partially-exposed warning or indication. As shown in FIGS. 11 and 12, when the spool 14 is at a predetermined second-obtuse angle of rotation 46 the indicator flag 30 is at the same angle to be positioned in the window 36, to provide a visual film-completely-exposed warning or indication. As shown in FIGS. 13 and 14, when the spool 14 is at a predetermined third-obtuse angle of rotation 48 the indicator flag 30 is at the same angle to be positioned in the window 38, to provide a visual film-processed warning or indication. 
     Camera 
     A partially shown camera 50 with which the film cassette 10 is to be used is shown in FIGS. 1 and 15. 
     Looking at FIG. 15, the camera 50 includes a cassette chamber 52 for the film cassette 10. The chamber 52 is open at its top and bottom, and has a film egress/ingress slot (not shown) opposite the film egress/ingress slot 20 in the cassette shell 12 to permit film movement out of and back into the chamber. An exterior top housing portion 54 of the camera 50 has a tool ingress opening 56 which is located coaxially above the drive cavity 28 of the light lock 18. A bottom lid 58 of the camera 50 normally seals the chamber 52 at its bottom. The lid 58 has a thin peripheral lip (not shown) that is snugly received within the chamber 52 to removably hold the lid in place. 
     Looking at FIGS. 1 and 2, an actuator unit 60 for pivoting the light lock 18 closed after the trailing film end portion 22 is wound into the cassette shell 12 comprises an integral single-piece driver 62 and film sensor lever 64. The film sensor lever 64 has a sensor head 66 shown in FIGS. 1 and 2 in contact with the trailing film end portion 22. The driver 62 has a depending drive-part 68 located in the drive cavity 28 of the light lock 18 to rotationally engage the light lock in order to pivot the light lock closed, and a coaxial upstanding gear-support-part 70 on which is coaxially fixed a first spur gear 72. Rotation of the first spur gear 72 in in a counter-clockwise direction in FIGS. 1 and 2 similarly rotates the drive-part 68 to pivot the light lock 18 closed. 
     A manual film rewind thumbwheel 74 has a depending coaxial drive-part 76 located in the drive cavity 24 of the spool 14 to rotationally engage the spool. The thumbwheel 74 is manually rotated in a film winding direction 78 to similarly rotate the spool 14 to wind the filmstrip 16 including the trailing film end portion 22 into the cassette shell 12. 
     A second spur gear 80 continuously in mesh with the first spur gear 72 is coaxially fixed to a locking lever 82. A mount-pin 84 rotationally supports the second spur gear 80 and the locking lever 82, and maintains the second spur gear continuously spaced from the thumbwheel 74. As shown in FIGS. 1-4 and 15, the locking lever 82 is normally located beneath the tool ingress opening 56 in the top housing portion 54 to cover or block the tool ingress opening. 
     A tension spring 86 biases the locking lever 82 to rotate with the second spur gear 80 in a clockwise direction in FIG. 1 to, in turn, bias the first spur gear 72 to rotate in a counter-clockwise direction in FIG. 1 to urge the sensor head 66 of the film sensor lever 64 against the filmstrip 16. Film resistance at the sensor head 66 is greater than the bias of the spring 66. As a result, the spring 86 is prevented from urging the locking lever 82 to rotate with the second spur gear 80 in a clockwise direction in FIG. 1 in order to move one end 88 of the locking lever against an arcuate rib 90 on the thumbwheel 74. Instead, the lever end 88 is held spaced a slight distance 92 from the arcuate rib 90. 
     Operation 
     Going from FIGS. 1 and 2 to FIG. 3, when the thumbwheel 74 is rotated in the film winding direction 78 the trailing film end portion 22 is drawn from the sensor head 66 of the film sensor lever 64 and into the slot 20 in the cassette shell 12. Once the trailing film end portion 22 is moved clear of the sensor head 66 the resulting absence of film resistance at the sensor head allows the spring 86 to rotate the locking lever and the second spur gear 80 clockwise in FIG. 3 until the lever end 88 abuts the arcuate rib 90 on the thumbwheel 74. Consequently, the actuator unit 60 is rotated counter-clockwise in FIG. 3 via the first spur gear 72 to make the drive-part 68 similarly pivot the light lock 18 initially closed ten degrees as shown in FIG. 3, to partially (slightly) close the light lock. 
     In FIG. 4, the thumbwheel 74 is rotated further in the film winding direction 78 than in FIG. 3 to draw the trailing film end portion 22 from the slot 20 and into the interior of the cassette shell 12 and to position a gap 94 in the arcuate rib 90 opposite the lever end 88. The presence of the gap 94 opposite the lever end 88 allows the spring 86 to rotate the locking lever 82 and the second spur gear 80 clockwise in FIG. 4 until the lever end is seated in the gap. Consequently, the actuator unit 60 is rotated counter-clockwise in FIG. 4 via the first spur gear 72 to make the drive-part 68 similarly pivot the light lock 18 further closed twenty degrees as shown in FIG. 4. 
     In FIG. 5, the thumbwheel 74 is rotated further in the film winding direction 78 than in FIG. 4 to draw the trailing film end portion 22 further into the interior of the cassette shell 12 and to make the arcuate rib 90 pivot the lever end 88 to rotate the locking lever 82 and the second spur gear 80 clockwise in FIG. 5. Consequently, the actuator unit 60 is rotated counter-clockwise in FIG. 5 via the first spur gear 72 to make the drive-part 68 similarly pivot the light lock 18 further closed thirty degrees as shown in FIG. 5. 
     In FIG. 6, the thumbwheel 74 is rotated further in the film winding direction 78 than in FIG. 5 to draw the trailing film end portion 22 further into the interior of the cassette shell 12 and to make the arcuate rib 90 pivot the lever end 88 to rotate the locking lever 82 and the second spur gear 80 clockwise in FIG. 5 until the lever end is pivoted out of the gap 94. Consequently, the actuator unit 60 is rotated counter-clockwise in FIG. 6 via the first spur gear 72 to make the drive-part 68 similarly pivot the light lock 18 further closed thirty-two degrees as shown in FIG. 6, to completely close the light lock. 
     At this time, a locking tooth 96 on the underside of the locking lever 82 is moved into engagement with the thumbwheel 74 to prevent further rotation of the thumbwheel in the film winding direction 78 as shown in FIGS. 6 and 16. The locking tooth 96 secures the thumbwheel 74 with the spool 14 at the predetermined second-obtuse angle of rotation. As shown in FIGS. 11 and 12, when the spool 14 is at the predetermined second-obtuse angle of rotation 46 the indicator flag 30 is at the same angle and, therefore is positioned in the window 36 to provide a visual film-completely-exposed warning or indication. 
     Also, the locking lever 82 uncovers the tool ingress opening 56 in the top housing portion 54. Then, as shown in FIGS. 16 and 17 a manual insertion tool 98 can be inserted through the ingress opening 56 and against the first spur gear 72 to force the actuator unit 60 and the film cassette 10 downward in the chamber 52 and out of the bottom of the chamber. The film cassette 10 is pushed against the bottom lid 58 to pop the bottom lid away from the chamber. 
     The invention has been described with reference to a preferred embodiment. However, it will be appreciated that variations and modifications can be effected by a person of ordinary skill in the art without departing from the scope of the invention. For example, instead of the locking tooth 96 on the underside of the locking lever 82, the lever end 88 can have a hooked end 100 that engages one end 102 of the arcuate rib 90 as shown in FIG. 18 to prevent further rotation of the thumbwheel 74 in the film winding direction 78 (much in the same way the locking tooth does). 
     PARTS LIST 
     10. film cassette 
     12. cassette shell 
     14. flanged spool 
     16. filmstrip 
     18. light lock 
     20. slot 
     22. trailing film end portion 
     24. drive cavity 
     26. drive end 
     28. drive cavity 
     30. indicator flag 
     32. window 
     34. window 
     36. window 
     38. window 
     40. VEI end 
     42. acute angle of rotation 
     44. first-obtuse angle of rotation 
     46. second-obtuse angle of rotation 
     48. third-obtuse angle of rotation 
     50. camera 
     52. cassette chamber 
     54. top housing portion 
     56. tool ingress opening 
     58. bottom lid 
     60. actuator unit 
     62. driver 
     64. film sensor lever 
     66. sensor head 
     68. drive-part 
     70. gear-support-part 
     72. first spur gear 
     74. film rewind thumbwheel 
     76. drive-part 
     78. film winding direction 
     80. second spur gear 
     82. locking lever 
     84. mount-pin 
     86. tension spring 
     88. lever end 
     90. arcuate rib 
     92. slight distance 
     94. gap 
     96. locking tooth 
     98. insertion tool 
     100. hooked lever end 
     102. rib end