Apparatus and method for separating spliced strips of photographic film

A semi automatic film de-splicer that non-destructively separates film strips from splice tapes attached to the film strips with thermal adhesive. A reciprocating heat shoe is operated in two de-splicing cycles to press and heat the splice tape adhesive separately in each adhesive region of the tape. In the first cycle, in which one film strip is restricted from movement, the other film strip is placed in tension by a tensioning device mounted on the film strip holding roller. When the adhesive is softened and the heat shoe is released, the tensioned pulls the film strip free of the splice tape. The heat shoe then presses and reheats the free end of the splice tape against an underlying pickup web to tack the splice tape to the web. The web is then advanced to place the remaining adhesive region attaching the splice tape to the other film strip under the heat shoe and the other film holding roller is placed in tension. The heat shoe is then actuated in a second de-splicing cycle to press and heat the second adhesive region allowing the tensioned roller to pull the remaining film strip free of the splice tape when the heat is released. The web is then advanced to remove the tacked-on splice from the area of the heat shoe allowing a new film splice to be inserted into the de-splicer.

FIELD OF THE INVENTION 
The invention relates to photography, and the removal of splices from the 
ends of film strips. More specifically the invention relates to the 
non-destructive separation of film strips from splices with the ends of 
the film strips intact. 
BACKGROUND OF THE INVENTION 
Typically exposed photographic film is spliced together for development and 
printing to facilitate handling of the film in automated equipment. 
Individual film rolls are removed from their containers, called cartridges 
or cassettes, and the resulting film strips are coupled together 
end-to-end with splices. The coupled strips form a long ribbon that is 
threaded and follows a sinuous path through processing equipment, into and 
out of developing solutions and drying chambers. Most of the processing 
steps are completed in the dark. Such rough handling, and the severe 
consequences of a break, require a secure attachment at every splice. The 
splices include a tough paper or plastic backing coated with a thermal 
adhesive. Usually the splices are applied to the film strips with heat and 
pressure. 
In the case of 135 mm film, after processing, the film is cut to remove the 
splices and again to divide the film strip corresponding to a complete 
customer order into smaller segments, such as four, five or six negative 
frames per segment. This is anticipated during film manufacture, when 
leaders and trailers at the ends of the film strips are provided with 
extra material. 
In a newly introduced photographic system, generally referred to as the 
Advance Photographic System (APS), the film strips are returned after 
processing to a cartridge similar to the cartridge used for loading the 
film into the camera. The splice may still be removed by cutting, but the 
cut film strip must then be reinserted into the cartridge for return to 
the customer. Although cutting is a simple approach for removing splices, 
it obviously damages and shortens the film compared to its manufactured 
state. APS film strips have a special configuration at their leading and 
trailing ends. At the trailing end the shape facilitates attachment of the 
film to a spool inside the cartridge. At the leading end the shape reduces 
friction at the cartridge exit to facilitate thrusting out of the film for 
viewing or reordering prints. When the film is cut, the configuration and 
its accompanying features either are lost, or must be included in the 
cutting die. 
Film strips typically are manufactured with extra material to accommodate 
splice removal during processing. Again the approach is simple, but adds 
material expense, including silver, a precious metal. This material then 
must be disposed of after processing. The amounts are small when compared 
to a single film strip, but build up at the photofinishing level. Silver 
is a heavy metal that requires special disposal procedures. For the 
foregoing reasons, therefore, it is desirable to provide apparatus and 
methods for removing the splice tape from film strips after the processing 
steps without damaging the leading and trailing ends of the filmstrips. 
In commonly assigned U.S. Pat. No. 5,373,339, non-destructive, automated 
method and apparatus for de-splicing photographic film is shown in which a 
film splice and splice pick-up web are positioned between a vertically 
reciprocating heat shoe and an platen. The heat shoe is pressed down to 
the splice to heat the thermal splice adhesive thereby allowing the film 
strips to be pulled free of the splice when the heat shoe pressure is 
removed. In order to retain the detached splice tape in position over the 
splice pickup web while the films are pulled apart, a retaining rod 
aligned with the splice space between the two film strips is pressed up 
through the platen surface to hold the splice tape against the heat until 
the films have been removed Once the films are removed, the heat shoe and 
retaining rod are then lowered to tack the splice tape to the splice 
pickup web and the web is advanced to remove the splice tape from the area 
of the heat shoe. While satisfactory for its purpose, it requires accurate 
positioning of the film in the heat shoe area to ensure proper alignment 
of the retaining rod with the splice space between the film strips. 
Additionally, if the film strips are contiguous, without any space between 
the film strips, it requires that the film strips be cut to separate them 
from each other, which damages the film strip ends leaves the splice tape 
on the film ends, an unsatisfactory situation, particularly at the leader 
end which can interfere with smooth thrusting of the film strip from its 
storage cartridge. 
SUMMARY OF THE INVENTION 
In accordance with the invention therefore, there is provided apparatus for 
separating first and second photographic film strips from a splice tape, 
the film strips being attached with thermal adhesive to first and second 
regions, respectively, of the splice tape. The apparatus comprises a 
platen; and a reciprocating heat shoe operable to press against the splice 
tape in successive de-splicing cycles. The apparatus also includes means 
for positioning a splice pickup web between the spliced film and the 
platen, means for placing the first film strip under tension after 
positioning the first region of the splice tape between the hot shoe and 
the platen, and means for restricting movement of the second film strip 
while the first film strip is held under tension. The heat shoe is 
operable during a first de-splicing cycle to press against the first 
region of the splice tape to soften the adhesive in the first region and 
allow the tension on the first film strip to pull the first film strip 
free of the splice tape. The hot shoe is further operable during the first 
de-splicing cycle to press the first region of the splice tape onto the 
pickup web thereby tacking the splice tape to the web. The apparatus 
further includes means for placing the second film strip under tension 
after positioning the second region of the splice tape between the hot 
shoe and platen; the hot shoe then being operable in a second de-splicing 
cycle to press against the second region of the splice tape to soften the 
adhesive in the second region and allow the tension on the second film 
strip to pull the second film strip free of the splice tape. 
In accordance with a second aspect of the invention, method of separating 
photographic film strips attached to first and second adhesive regions of 
a splice tape comprises the steps of positioning the first splice tape 
region between a hot shoe and a platen; positioning a pickup web between 
the hot shoe and platen on a side of the films opposite to the splice 
tape; restricting the film strip attached to the second splice tape region 
from movement; placing the film strip attached to the first splice tape 
region under tension; bringing the hot shoe and platen together under 
pressure in a first de-splicing cycle to heat and soften splice tape 
adhesive in said first splice tape region; and releasing the pressure on 
the first splice tape region sufficiently to allow one film strip to be 
pulled free of the splice tape. The method further comprises the steps of 
bringing the hot shoe and platen together under pressure after removal of 
the first film strip to adhere the first region of the splice tape to the 
carrier web, positioning said second splice tape region between said hot 
shoe and platen; placing the other film strip attached to the second 
splice tape region under tension; bringing the hot shoe and platen 
together under pressure in a second de-splicing cycle to heat the adhesive 
in the second splice tape region; and releasing said second cycle pressure 
to allow the other film strip to be pulled free of the splice tape. 
These and other aspects, objects, features and advantages of the present 
invention will be more clearly understood and appreciated from a review of 
the following detailed description of the preferred embodiments and 
appended claims, and by reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE INVENTION 
Referring to FIG. 1, a preferred embodiment of film de-splicer apparatus 10 
is depicted for removing the leading and trailing ends of two film strips 
14 and 16, respectively, from splice tape 12. The de-splicer apparatus 
includes a reciprocating hot shoe 18 and an opposed platen 20 that move 
relative to each other for capturing and heating the splice tape 12. Film 
positioning and tensioning roller mechanisms 30 and 40 are located, 
respectively, on opposite sides of the hot shoe 18 and serve to hold the 
film strips with the splice tape 12 in place between the hot shoe and 
platen. The roller mechanisms each include tensioning means to hold the 
film strips selectively under tension during successive cycling of the hot 
shoe for separating the film strips from the splice in a manner to be 
described. A splice pickup web 50 extends from a supply reel 52 to a drive 
wheel 54 and is positioned between the spliced film strips and the platen 
to receive and remove splice tape after being separated from the film 
strips. 
Splice tape 12 is typical of products used by the photofinishing industry 
today and includes treated paper with a layer of thermal adhesive on one 
surface. Examples of such adhesive include Buna S, a 
poly(styrene-cobutadiene) and Buna N, a poly(acrylonitrile-cobutadiene), 
both widely available to the industry under a number of trade names. The 
splice tape 12 is applied to the film strips 14 and 16 at separated 
regions 12a and 12b, respectively, of the splice as shown in FIG. 2. 
Splice tape 12 is applied to film strip 14 and 16 with heat and pressure. 
The film strips thus are coupled securely together to make up a continuous 
web of film strips for film processing applications. The adhesive is a 
thermoplastic and will soften beginning at approximately 120.degree. C. 
Heat shoe 18 is coupled to an air piston 22 which is controlled by air 
piston controller 24 upon actuation by spaced-apart manual switches 25,26, 
to move the heat shoe in reciprocal manner to press against splice tape 12 
in successive de-splicing cycles to soften the thermal adhesive separately 
in each of the separate splice tape regions 12a and 12b. The roller 
mechanisms 30 and 40 comprise upper and lower rollers 32,34 and 42,44, 
respectively, for capturing and holding the film strips during the 
de-splicing operation. Both of the roller mechanisms are of similar 
construction and will be described in connection with roller mechanism 40 
in reference to FIGS. 4-9. As illustrated therein, the rollers 42, 44 are 
rotatably mounted on end supports 60, 62. Axle 43 of upper roller 42 is 
journalled at its back end to a hinged section of 60 and has its front end 
releasably engaged in slot 63 of front support 62 to allow the roller to 
be raised for insertion of a film strip between roller 42 and roller 44. 
An over-center, spring-loaded lock 64 captures and holds the axle 43 in 
slot 63 when the axle is inserted into the slot after a film strip is 
positioned between the rollers. A tensioning device 66 is provided on the 
front end of the axle 45 for lower roller 44. Tensioning device 66 
includes a manually operated tension-setting disc 68 mounted on axle 45 so 
as to be rotatable around and axially slidable relative to the axle. Knobs 
74a, 74b facilitate manual operation of the tensioning disc. A coil 
tension spring 76 is secured at one end to the axle 45 and at the other 
end to the tensioning disc 68 to place the film captured between roller 42 
and 44 under tension when the disc 68 is rotated, clockwise in the case of 
roller 44 and counterclockwise in the case of roller 34. A locking finger 
70 extends inwardly from disc 68 toward support 62 to engage one of 
several holes 78 formed in support 62 when the tensioning disc is slid 
towards the support after rotating the disc to put the roller under 
tension. Notch 72 serves to prevent the locking finger from slipping out 
of the hole. A locking device 36 is provided for releasably engaging the 
lower roller 34 to prevent movement of film strip 14 during a first 
de-splicing cycle in which film strip 16 is separated from region 12a of 
splice tape 12. The length of the rollers is preferably made approximately 
equal to the width of the film strip so that when the upper roller is 
locked down on the film, the pressure of the rollers will provide enough 
frictional force between the lower roller surface and the film surface to 
prevent rotation of the lower roller when rotational tension is applied to 
roller 34 or 44 by the respective tensioning device. 
The operation of the de-splicing apparatus will be described with reference 
to FIGS. 3a-3h. In FIG. 3a, spliced film strips 14 and 16 are shown placed 
between their respective rollers 32, 34 and 42, 44. Splice pick up web 50 
is positioned between splice tape 12 and platen 20. The film strips are 
positioned by the operator with splice tape region 12a aligned with hot 
shoe 18 and platen 20. Splice tape region 12b is positioned to the left of 
the hot shoe area. Locking device 36 is placed in engagement with roller 
34 to restrict movement of film strip 14 during the first de-splicing 
cycle in which film strip 16 is to be separated from splice tape 12. 
Tensioning disc 68 on roller 44 is rotated clockwise and locked in place 
to hold film strip 16 in tension against the restraining force applied by 
roller 34 to film strip 14. The air piston controller 24 is then activated 
by the operator depressing switches 25, 26 to initiate the first 
de-splicing cycle as shown in FIG. 3a in which hot shoe 18 is pressed 
against region 12a of the splice tape to heat and soften the thermal 
adhesive holding the splice tape to film strip 16. When the thermal 
adhesive is softened, the switches are released allowing air piston 
controller 24 to raise hot shoe 18 slightly as shown in FIG. 3b to release 
the pressure on the splice tape 12 thereby allowing the tensioned roller 
44 to pull film strip 16 free from splice tape 12. Once the film strip 16 
is separated from the splice, switches 25,26 are again depress to allow 
the hot shoe 18 to be moved downward to press the splice region 12a under 
pressure against the splice pick up web 50 as shown in FIG. 3c. The 
adhesive is reheated and the splice tape region 12a is thereby tacked to 
the pick up web 50. The switches are then released allowing hot shoe 18 to 
move upwards as shown in FIG. 3d to release the pressure on the splice 
thereby completing the first de-splicing cycle. As seen in FIG. 3e, 
locking device 36 is released from roller 34 to allow the operator to 
rotate web drive reel 54, using crank 55, to pull the web to the right 
thereby advancing the film strip 14 and splice tape 12 so as to position 
splice tape region 12b under the hot shoe 18. Preferably, reel 55 is 
provided with a ratchet and pawl mechanism, not shown, to prevent 
counterclockwise rotation of the reel after the film and splice have been 
advanced as described. Once the splice region 12b is positioned under the 
hot shoe, the operator rotates tensioning disc 68' (FIG. 3f) on roller 34 
counterclockwise to place film strip in tension against the restraining 
force applied by reel 54 through splice tape 12 tacked onto the pick up 
web 50. A second de-splicing cycle is then initiated by actuating switched 
25, 26 to move hot shoe 18 downward pressing against splice tape 12. The 
hot shoe heats and softens the adhesive in splice tape region 12b. The 
switches 25,26 are then released to raise the hot shoe as shown in FIG. 3g 
to release pressure on the splice tape thereby allowing the tensioning 
force exerted by roller 34 to pull film strip 14 free of splice tape 12. 
Reel 54 is then rotated clockwise by the operator as shown in FIG. 3h to 
pull the splice tape away from the de-splicing area after which the upper 
rollers 32 and 42 can be released and raised by the operator for removal 
of the de-spliced film strips and insertion of another pair of spliced 
film strips. 
The invention has been described in detail with particular reference to 
certain preferred embodiments thereof, but it will be understood that 
variations and modifications can be effected within the spirit and scope 
of the invention.