Control for strip-driving apparatus

Claim 2

Apparatus for projecting selected images from a filmstrip and including first and second stations for storing such filmstrip, said apparatus comprising: a. drive means for driving a filmstrip from said first to said second storing stations, b. a projection station located in said apparatus between said first and second storing stations and including transparent filmstrip guide means which is movable between a first position wherein a filmstrip can be driven by said drive means past said guide means without damaging the filmstrip and a second position for supporting a filmstrip at said projection station in a position for projecting a selected image of the filmstrip, and c. control means operable associated with said guide means and said drive means for transposing said guide means between its first and second positions and for energizing and deenergizing said drive means, said control means including delay means for delaying transposition of said guide means from its first to its second position for a delay period dependent upon the length of time said drive means has been energized.

Claim 3

Apparatus for projecting selected images from a filmstrip directed from a first filmstrip storage station to a second filmstrip storage station, said apparatus comprising: a. motor means operably associated with said first and second filmstrip stations for driving the filmstrip therebetween, b. a projection station located in said apparatus between said first and second filmstrip storage stations and including first and second transparent plates disposed to accommodate a filmstrip therebetween, said plates being movable with respect to one another, c. means for moving at least one of said first and second plates connected thereto for changing the relative position of said plates from a first position wherein a selected image of the filmstrip is clamped therebetween to a second position wherein said plates are spaced apart a distance at least exceeding the minimum thickness of the filmstrip thereby facilitating movement of the filmstrip between said first and second plates, and vice versa, and d. control means connected to said motor means and said means for moving for controlling the operation thereof, said control means including delay means for delaying transposition of said plates from said second to said first positions for a delay period initiated by disenablement of said motor means and dependent upon the length of time said motor means has been operated, said motor means enabled by said control means only when said plates are disposed in said first position, said plates being disposed in said second position only after said delay period has expired.

Claim 4

Apparatus for projecting selected images from a filmstrip directed from a first filmstrip storage station to a second filmstrip storage station, said apparatus comprising: a. motor means operably associated with said first and second filmstrip stations for driving the filmstrip therebetween, b. a projection station located in said apparatus between said first and second filmstrip storage stations and including first and second transparent plates disposed to accommodate a filmstrip therebetween, said plates being movable with respect to one another, c. means for moving at least one of said first and second plates connected thereto for changing the relative position of said plates from a first position wherein a selected image of the filmstrip is clamped therebetween to a second position wherein said plates are spaced apart a distance at least exceeding the minimum thickness of the filmstrip thereby facilitating movement of the filmstrip between said first and second plates, and vice versa, and d. control means connected to said motor means and said means for moving for controlling the operation thereof, said control means including delay means for delaying transposition of said plates from said second to said first positions for a delay period initiated by disenablement of said motor means and dependent upon the length of time said motor means has been operated, said motor means enabled by said control means only when said plates are disposed in said first position, said plates being disposed in said second position only after said delay period has expired.

Claim 5

Apparatus as claimed in claim 2, wherein said control means includes switch means having a first position for applying a source of potential to said motor means and a second position for disconnecting the potential source from said motor means, capacitive means responsive to the position of said switch means for storing an electrical signal while said switch means is disposed in its first position, and circuit means connected to said capacitive means for selectively discharging said capacitive means when said switch means is disposed in its second position.

Claim 6

Apparatus as claimed in claim 3 wherein said means for moving includes a solenoid and solenoid coil operable coupled to said first and second plates to change the relative position thereof, said solenoid coil being connected to said circuit means to that said circuits means discharges said capacitive means through said solenoid coil when said switch is disposed in its second position.

Claim 7

In apparatus for projecting selected images from a filmstrip being directed between a first filmstrip storage station and a second filmstrip storage station: a. reversible motor means operatively associated with Said first and second filmstrip storage stations for driving the filmstrip therebetween, b. a projection station located in said apparatus between said first and second filmstrip storage stations and including first and second transparent plates disposed to accommodate a filmstrip therebetween, said plates being movable with respect to one another, c. means for moving at least one of said first and second plates connected thereto for changing the relative position of said plates from a first position wherein a selected image of the filmstrip is clamped therebetween to a second position wherein said first and second plates are separated a distance at least exceeding the minimum thickness of the filmstrip thereby facilitating movement of the filmstrip between said first and second plates, and vice versa, and d. control means connected to said motor means and said means for moving for controlling the operation thereof, said control means including first switch means disposable in a first position for applying potential signals from a source thereof to said motor means and said means for moving and in a second position for disconnecting the potential signals from said motor means and said means for moving capacitor means for storing a potential charge which is a function of the time said first switch means is disposed in said first position, and one-way conductive means cooperably connected to said means for moving for discharging said capacitive means therethrough when said first switch means is disposed in said second position to thereby cause said means for moving to dispose said plates in said first position only after said capacitive means has been discharged.

Claim 8

In apparatus for projecting selected images from a filmstrip being directed between a first filmstrip storage station and a second filmstrip storage station: a. reversible motor means operatively associated with Said first and second filmstrip storage stations for driving the filmstrip therebetween, b. a projection station located in said apparatus between said first and second filmstrip storage stations and including first and second transparent plates disposed to accommodate a filmstrip therebetween, said plates being movable with respect to one another, c. means for moving at least one of said first and second plates connected thereto for changing the relative position of said plates from a first position wherein a selected image of the filmstrip is clamped therebetween to a second position wherein said first and second plates are separated a distance at least exceeding the minimum thickness of the filmstrip thereby facilitating movement of the filmstrip between said first and second plates, and vice versa, and d. control means connected to said motor means and said means for moving for controlling the operation thereof, said control means including first switch means disposable in a first position for applying potential signals from a source thereof to said motor means and said means for moving and in a second position for disconnecting the potential signals from said motor means and said means for moving capacitor means for storing a potential charge which is a function of the time said first switch means is disposed in said first position, and one-way conductive means cooperably connected to said means for moving for discharging said capacitive means therethrough when said first switch means is disposed in said second position to thereby cause said means for moving to dispose said plates in said first position only after said capacitive means has been discharged.

Claim 9

Apparatus as claimed in claim 5 wherein said control means includes second switch means interconnected between said first switch means and said motor means for reversing the potential signals applied to said motor means to thereby reverse the direction in which the filmstrip is driven.

Claim 10

Apparatus as claimed in claim 6 which includes low impedance means connected to said second switch means and wherein said motor means includes an armature winding, said second switch means connecting said low impedance means across said armature winding only when said first switch means is disposed in its second position.

Claim 11

Apparatus as claimed in claim 5 wherein said control means includes a silicon controlled rectifier connected to apply the potential signals to said motor means during its periods of conduction having a gate for controlling the periods of conduction of said silicon controlled rectifier and selectively variable impedance means connected to said gate for controlling the initiation point of the periods of conduction of said silicon controlled rectifier.

Claim 12

Apparatus as claimed in claim 8 wherein said motor means includes an armature winding, and said control means includes switch means and low-impedance means connected thereto, said second switch means being interconnected between said first switch means and said armature winding and responsive to the position of said first switch means for connecting said low-impedance means across said armature winding when said first switch means is disposed in said second position.

Claim 13

Apparatus as claimed in claim 9 wherein said control means includes third switch means and low impedance means connected thereto, said third switch means being interconnected between the source of potential signals, said silicon controlled rectifier and said armature winding and disposable in a first position to place said silicon-controlled rectifier in circuit between said motor means and the source of potential signals and disposable in a second position to place said low impedance means across said silicon controlled rectifier and between the source of potential signals and said armature winding to thereby increase the speed of said motor means. 11 Apparatus as claimed in claim 10 wherein said motor means includes a shunt field coil and said control means incLudes fourth switch means connected between the source of potential signals and said shunt field coil disposable in a first position to apply potential signals from the source to said shunt field coil and in a second position to remove the potential signals from said shunt field coil.

Claim 14

Apparatus as claimed in claim 11 wherein said control means includes a manually operable member connected to said first, second, third and fourth switch means for actuating said first, second, third and fourth switch means substantially in unison.

Claim 15

Apparatus as claimed in claim 1 wherein said drive means is energized by said control means only when said guide means is disposed in its first position, said guide means being transposed by said control means to its second position only after said delay period has expired.