Photographic camera having an improved film transport mechanism

A photographic camera has a fork disposed in a cassette receiving chamber to be coupled to a spool core of a photographic film cassette. Photographic film from the photographic film cassette is wound on a take-up reel disposed in a photographic film take-up chamber. A magnetic head is disposed on a frame of an exposure aperture, and reads/writes data on a magnetic recording area of the photographic film. A brake pad applies load to the fork, and keeps the photographic film in such a tension as to ensure flatness during the one-frame feeding. A guide member is formed to project from an inner wall of the photographic film take-up chamber. When a photographic film leader is advanced into the photographic film take-up chamber, the photographic film leader is guided downstream from the take-up reel against a curling tendency.

BACKGROUND OF THE INVENTION 
1. Field of the Invention: 
The present invention relates to a photographic camera provided with a 
mechanism for recording data, such as exposure data, and more particularly 
to an improvement of a photographic film transporting system. 
2. Description of the Related Art: 
In a conventional photographic camera, an auto-loading mechanism is 
incorporated, for facilitating photographic film-loading, wherein the 
leading end of a photographic film leader is automatically captured on a 
take-up reel in a photographic film take-up chamber. Before loading, the 
photographic film leader of the conventional photographic film cassette is 
maintained in a state in which it protrudes from a photographic film 
passage mouth of the cassette shell. The protruded photographic film 
leader is inserted together with the cassette shell in the camera, fed to 
the photographic film take-up chamber by the auto-loading mechanism, and 
captured on the take-up reel. 
A camera, in which photographic film provided with a magnetic recording 
area is utilized and which reads/writes data thereon, is known and is 
disclosed in International Publications WO 90/04201 and 90/04202. This 
camera incorporates a magnetic head, which reads/writes data on the 
magnetic recording area while the photographic film is transported between 
the photographic film take-up reel and the photographic film cassette. 
Such data includes photographic film data, e.g., type of photographic 
film, photographic sensitivity, numbers of frames and the like, as stored 
during a manufacturing process, for use in taking photographs, and 
photo-taking data as written during photo-taking for use in making prints. 
Also, a photographic film cassette is known in which a photographic film 
leader does not originally protrude from the cassette shell, and which is 
thus more easily loaded in a camera. Such a film cassette is disclosed in 
U.S. Pat. Nos. 4,832,275, 4,834,306, and 4,846,418. Rotation of a spool 
core by means of the fork of the camera in the direction of unwinding the 
photographic film causes the photographic film leader to advance to the 
outside of the cassette shell through the photographic film passage mouth. 
The cassette shell is provided with a device, e.g., annular ridges, for 
preventing the roll of photographic film from loosening when the spool 
core is rotated. Such a cassette transmits the rotary force of the spool 
core to the photographic film leader. 
Because the photographic film is kept wound in the roll in the conventional 
photographic film cassette, a strong tendency to curl remains in the 
photographic film even when unwound. The photographic film of the 
above-described type of photographic film cassette has an additional 
curling tendency in the photographic film leader. Curl in photographic 
film causes problems in the camera when the photographic film is advanced 
and transported. When the take-up reel is rotated to transport the 
photographic film, the fork is left free, whereas the former is left free 
when the latter is rotated to transport the photographic film. In cameras 
with the above-described photographic film transporting system, the 
photographic film is flexed on lateral sides of the magnetic head due to 
the intermittent photographic film feeding. Accordingly, difficulties may 
arise in reading/writing data adequately due to poor contact between the 
film and a magnetic head. 
As illustrated in FIG. 8, during advancement of the photographic film 
leader of photographic film 3 toward a take-up reel 30 in the initial 
stage of photographic film transportation, the photographic film leader 
has a strong tendency to curl downward in FIG. 8 and thus moves in a 
photographic film take-up chamber 73 along its inner wall upstream from 
the take-up reel 30. Accordingly, the leading end of the photographic film 
leader may fail to be captured on the take-up reel 30, making it 
impossible to load the camera with the photographic film contained in the 
leader-propelling photographic film cassette. 
SUMMARY OF THE INVENTION 
In view of the foregoing problems, an object of the present invention is to 
provide a photographic camera having an improved photographic film 
transporting system which reliably transports photographic film which has 
a strong tendency to curl. 
Another object of the present invention is to provide a camera in which 
magnetic data can be reliably read/written on the photographic film. 
Still another object of the present invention is to provide a camera in 
which a photographic film leader can be reliably captured on a 
photographic film take-up reel automatically. 
In order to achieve the above and other objects and advantages of this 
invention, a load-applying device is provided in a camera for applying 
load to either the fork or the take-up reel, whichever is upstream 
relative to a photographic film transporting direction. The photographic 
film can thus be kept flat in spite of a curling tendency, and is 
prevented from flexing even when being intermittently fed. Also, data 
storage is improved by virtue of closer contact of the magnetic head with 
the photographic film. 
In accordance with a preferred embodiment, a guide member is provided in 
the camera so as to project from an inner wall of the photographic film 
take-up chamber for guiding the photographic film leader downstream from 
the take-up reel when the photographic film leader is advanced up to the 
photographic film take-up chamber. The photographic film leader can thus 
reliably be captured on a photographic film take-up reel automatically 
without interference due to a curling tendency of the photographic film 
leader.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 illustrates a preferred embodiment of the present invention and a 
photographic film cassette for use therewith. A camera body 21 is provided 
with a centralized exposure aperture when back door 20 is left open. A 
lens 23 is disposed in front of a frame 24 of the exposure aperture. A 
pair of photographic film guide rails 25 and 26 are formed in upper and 
lower positions on aperture frame 24. A reflection type photosensor 27 is 
provided on the aperture frame 24, so as to count perforations 12 in the 
film in order to detect an amount of feeding photographic film 3 (see FIG. 
2). Next to the aperture frame 24 is a cassette receiving chamber 28 and a 
photographic film take-up chamber 29, each formed in the camera body 21. 
The cassette receiving chamber 28 is loaded with a photographic film 
cassette 2, whereas the photographic film 3 is wound up in the 
photographic film take-up chamber 29. A photographic film take-up reel 30 
is rotatably provided in the photographic film take-up chamber 29. A 
plurality of capture members 30a are formed on the cylindrical surface of 
the take-up reel 30 for engaging with perforations of a photographic film 
leader fed from the cassette receiving chamber 28 out of the cassette 
shell 5. 
The photographic film cassette 2 consists of the photographic film 3, wound 
in a roll on a spool core 4 and a cassette shell 5 for containing the 
photographic film 3 in a light-tight fashion. The cassette shell 5 
consists of a pair of plastic shell halves 5a and 5b. The photographic 
film leader is fully wound up and contained in the cassette shell 5, even 
in the unused state. The photographic film leader is propelled to the 
outside of the cassette shell 5 when the spool 4 is rotated in a direction 
of unwinding. 
A lower opening 31 of the cassette receiving chamber 28 is formed on the 
bottom of the camera body 21, through which opening 31 the photographic 
film cassette 2 is loaded in the cassette receiving chamber 28. It is 
noted that, in operation, the back door 20 will be opened just enough to 
expose the lower opening 31. However, back door 20 is shown to be open 
widely in FIG. 1 for the purpose of clearly illustrating the structure of 
the camera body 21. A fork 32, to be rotated by a motor described below, 
is disposed in the innermost surface of the cassette receiving chamber 28 
for being engaged with the spool core 4 so as to rotate it. A cassette 
detecting switch 33 is provided near the fork 32 for detecting the 
presence of a photographic film cassette 2 in the cassette receiving 
chamber 28. A ridge 34 is formed on the cassette receiving chamber 28 for 
positioning the cassette shell 5. 
The back door 20 is provided with a conventional pressure plate 35. A 
magnetic head 37 is disposed on the back door 20 for recording and reading 
data on a magnetic recording area 14 on the photographic film 3 (see FIG. 
2). The magnetic head 37 penetrates the pressure plate 35 through a hole 
therein so as to be in contact with the photographic film 3. A bottom 
portion 38 is formed integrally with the back door 20 for preventing outer 
light from entering the bottom of the camera body 21. The open/closed 
state of the back door 20 is detected by a back door switch 39 provided 
beside the cassette receiving chamber 28. A shutter release button 40 is 
also provided on the camera body 21. 
FIG. 2 illustrates the relevant circuits for photographic film 
transportation and magnetic recording. The fork 32 is driven by a motor 48 
via a gear 46 and a clutch 47. A first brake pad 49 is in contact with the 
shaft of the fork 32. One end of the first brake pad 49 is engaged with a 
first solenoid 50, whereas its other end is biased by a spring 51. When 
the first solenoid 50 is driven, the first brake pad 49 is caused to apply 
a frictional load to the fork 32 in the range of 50 to 200 gf.cndot.cm, 
preferably 50-100 gf.cndot.cm. The take-up reel 30 is driven by the motor 
48 via a gear 53 and a clutch 54. A second brake pad 57 is mounted on the 
take-up reel 30. One end of second brake pad 57 is engaged with a second 
solenoid 55, and the other end thereof is biased by a spring 56. The 
second brake pad 57 presses the take-up reel 30 so as to apply a load in 
the range of 50 to 200 gf.cndot.cm, similar to the first brake pad 49. A 
controller 58 is provided to control the motor 48, clutches 54 and 47, and 
the solenoids 50 and 55. The controller 58 is also connected to a 
microcomputer 59 for controlling the relevant circuits of the camera. 
The cassette detecting switch 33, the back door switch 39 and the release 
button 40 are connected to the microcomputer 59 respectively via signal 
generators 60, 61, and 62. A ROM 63, for storing a program relating to 
controlling the camera, a RAM 64 for provisionally storing data at the 
time of executing the control program, and a reading/writing circuit 65 
for driving the magnetic head 37 to read/write data are all coupled to the 
microcomputer 59. The operation of the reading/writing circuit 65 is 
controlled by the microcomputer 59 when either winding up or rewinding the 
photographic film 3. 
FIGS. 3 and 4 illustrate the photographic film cassette utilized with the 
above-described camera of the preferred embodiment. Inside the cassette 
shell 5 are formed a pair of arcuate ridges 6a and 6b on the lateral 
surfaces along a portion of a circle and a pair of annular ridges 7a and 
7b on the cylindrical surface. The annular ridges 7a and 7b are in contact 
with the outermost surface of the roll of photographic film 3 in order to 
prevent it from loosening. The arcuate ridges 6a and 6b press spool 
flanges 8a and 8b formed on the spool 4 in an inward direction. The spool 
flanges 8a and 8b are thus caused to nip the lateral ends of the outermost 
turn so as to tend to tighten the turns of photographic film 3 in the 
upstream position from a port portion 10 of the photographic film cassette 
2. 
Separating claws 9 are formed integrally with the annular ridges 7a and 7b 
as illustrated in FIG. 3. The separating claws 9 are in contact with the 
leading end of the photographic film 3 during the first rotation in the 
unwinding direction so as to separate it from the roll of photographic 
film 3 and allow it to pass through a photographic film passage mouth 11 
formed on the port portion 10 toward the exterior of the cassette. The 
port portion 10 is positioned on the ridge 34 of the cassette receiving 
chamber 28. In this photographic film cassette, the leading end of the 
photographic film 3 is propelled to the outside when the spool core 4 is 
rotated in the unwinding direction. 
FIG. 5 illustrates the photographic film 3 to be exposed in the camera of 
the preferred embodiment. The perforations 12 are formed on film 3 on the 
portions thereof along lateral edges in the lengthwise direction. Along 
one of the lateral edges is formed a magnetic recording area 14 interior 
to the perforations 12 as indicated by the two-dot-dash lines. The 
magnetic recording area 14 is disposed so as to be outside image frames 15 
to be recorded. Although disposed along one lateral edge of the 
photographic film 3, magnetic recording areas may also be formed along 
both lateral edges, or on the whole of one surface of the photographic 
film 3. If the magnetic recording area 14 is formed on the whole surface, 
it is necessary to form the magnetic recording layer from transparent 
material. 
The operation of the camera of the preferred embodiment now will be 
described below. When the back door 20 is closed with the photographic 
film cassette 2 loaded in the cassette receiving chamber 28, the signal 
generators 60 and 61 supply signals to the microcomputer 59, which outputs 
a drive signal to the controller 58 in accordance with the program in the 
ROM 63. The controller 58 controls the motor 48 to rotate in the normal 
direction and drives the clutches 47 and 54. In the wind-up direction or 
frame-by-frame feeding direction, the motor 48 rotates the fork 32 via the 
clutch 47 and gear 46 as well as the take-up reel 30 via the clutch 54 and 
the gear 53. 
When the fork 32 rotates the spool core 4, the photographic film leader is 
propelled out of the cassette shell 5, and slid on the guide rails 25 and 
26 to reach the photographic film take-up chamber 29. As soon as the 
photographic film leader is captured on the take-up reel 30, the 
controller 58 stops driving the clutch 47 so as to set the fork 32 free. 
The controller 58 drives the first solenoid 50 to press the first brake 
pad 49 against the fork 32. Load is applied to the fork 32 to keep the 
photographic film 3 under tension as the take-up reel 30 rotates. Thus, 
the photographic film 3 is kept flat and the magnetic recording area 14 is 
placed in good contact with the magnetic head 37. The data stored in the 
magnetic recording area 14 is read by the magnetic head 37 while the 
photographic film 3 is fed. A first frame to be exposed is set on the 
aperture frame 24 and the motor 48 is stopped. 
The shutter release button 40 is then depressed to take a photograph. The 
controller 58 then drives the first solenoid 50 to press the first brake 
pad 49 against the fork 32, drives the motor 48 again in the normal 
direction, and drives the clutch 54. The take-up reel 30 is rotated in the 
feeding direction to feed the photographic film 3 frame by frame. The 
first brake pad 49 keeps the photographic film 3 under tension so as to be 
in good contact with the magnetic head 37. The read/write circuit 65 
writes photo-taking data onto the magnetic recording area 14 via the 
magnetic head 37 during the period of feeding one frame of film. The 
taking of photographs and writing of phototaking data is successively 
repeated for each frame. When the last phototaking data is written, the 
microcomputer 59 supplies the controller 58 with a photographic film 
rewinding signal. 
At this time, the controller 58 drives the second solenoid 55 to press the 
second brake pad 57 against the take-up reel 30. The controller 58 then 
drives the motor 48 to rotate in the reverse direction while activating 
the clutch 47. The fork 32 is thus rotated in the rewinding direction. The 
photographic film 3 as rewound is kept under tension so that the magnetic 
head 37 is in good contact with the magnetic recording area 14. The 
read/write circuit 65 can read the data written while feeding the 
photographic film 3 out of the magnetic recording area 14 via the magnetic 
head 37. The photographic film 3 can be checked according to the data as 
stored, because end faces of the rewound roll of photographic film 3 are 
neatly flattened. 
When the photographic film 3 is rewound up to the photographic film leader, 
the motor 48 is stopped. It is noted that the magnetic head 37 may 
read/write data onto the magnetic recording area 14 after the 
corresponding frame has passed. The inventive construction of the present 
camera is also applicable to a camera for use with a photographic film 
cassette of which the photographic film leader initially protrudes from 
the cassette shell. 
FIG. 6 illustrates a photographic film take-up chamber. In order to ensure 
that the photographic film leader is reliably captured on the take-up 
reel, the rear gap of a photographic film take-up chamber 70 is narrowed 
by virtue of a guide member 71 formed on the side portion of the aperture 
frame 24. Line L is parallel to the optical axis of the taking lens 23 
(see FIG. 2) and vertically intersects the axis of the take-up reel 30. 
Line R is parallel to the line L and passes through the end of the guide 
member 71. The desirable interval D between the lines L and R is 5 mm or 
less. The guide member 71 may also project over the line L. The 
photographic film leader as slid on the guide rails 25 and 26 is thus 
prevented from entering the spacing upstream from the take-up reel 30. 
This ensures reliable engagement between perforations 12 and capture 
members 30a. 
Although the guide member 71 is integrally formed on the side portion of 
aperture frame 24, a flexible tongue 72 may be fixed thereon instead so as 
to guide the photographic film leader in FIG. 7. For the tongue 72, the 
rightward ends of the guide rails 25 and 26 are retracted so that the 
tongue 72 is fixed on the area adjacent to the retracted ends, so that the 
upper surface of the tongue 72 is no higher than the top of the guide 
rails 25 and 26. In the alternative, a guide member may also be formed or 
fixed on the inner wall of the photographic film take-up chamber 70 
upstream from the take-up reel 30. 
When the spool core 4 is rotated so as to unwind the roll of photographic 
film 3 in the camera, the photographic film leader is propelled and 
advanced through the photographic film passage mouth 11 toward the take-up 
reel 30. The photographic film leader slides on the aperture frame 24 
until the photographic film reaches take-up chamber 70. In passing over 
the aperture frame 24, curl of the photographic film leader is flattened 
by the pressure plate 35 disposed face to face with the guide rails 25 and 
26, so as to slide the photographic film in a straight manner. When the 
photographic film leader is transported to the photographic film take-up 
chamber 70, it tends to curl toward the front side of the camera, when the 
leading end reaches the rotating take-up reel 30. The capture members 30a 
engage with the perforations 12. 
Reading/writing the data can be performed either during feeding or 
rewinding of the photographic film 3 in the preferred embodiment. However, 
it may be performed only when feeding the photographic film frame by 
frame, i.e., when transporting it in one of the two directions one frame 
at a time. Typically, data is read/written while the take-up reel winds 
the photographic film 3 frame by frame in the forward transporting 
direction. In such a case, the camera need only be provided with one brake 
pad on the fork. In a prewind type camera in which the whole photographic 
film is prewound on the take-up reel and drawn into the cassette shell 
frame by frame for exposure, data may be read/written while the fork winds 
the photographic film, frame by frame, in the rewinding direction in the 
camera. Such a camera is provided with one brake pad on the take-up reel. 
Although the solenoids are engaged with the brake pads for bringing them in 
contact with the fork and the take-up reel in the above embodiment, the 
solenoids may be omitted so that the brake pads are in constant contact 
with the fork and the take-up reel, and regulated to apply a load of 50 to 
200 gf.cndot.cm (preferably 50 to 100 gf.cndot.cm) when the fork and the 
take-up reel rotate. Further, when the take-up reel is rotated to feed the 
photographic film 3, the take-up reel may be provided with a load by 
subjecting the fork to a rotary drive of a low speed. Although a magnetic 
recording device is used to read/write data, an optical recording device 
may be used in its place. Further, in the preferred embodiment, the back 
door of the camera is constructed to be openable to expose the cassette 
receiving chamber and the photographic film take-up chamber. However, the 
present invention is also applicable to a camera as disclosed in Japanese 
Patent Laid-open Publication No. 2-195335, in which a side door instead of 
the back door is openable to expose only the cassette receiving chamber. 
Although the present invention has been fully described by way of the 
preferred embodiment thereof with reference to the accompanying drawings, 
various changes and modifications will be apparent to those having skill 
in this field. Therefore, unless otherwise these changes and modifications 
depart from the scope of the present invention, as defined by the appended 
claims, they should be construed as included therein.