US3719335A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic film rewinding device for small movie projectors
Assignee: RICOLI KK
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Filing: 1970-12-01
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Granted: 1973-03-06
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Expires: 1990-12-01
Abstract
Abstract An automatic film rewinding device for small movie projectors effects automatic rewinding of the film responsive to detection of tensioning of the film, wound on a supply reel, at the terminating stage of film supply, and is operable selectively to effect single-frame projection as well as projection of the film while the latter is moving in the rewinding direction. An externally accessible operating knob is operable to move a control cam group between forward film feed, neutral and reverse film feed positions, and a control lever group includes certain levers engaged with the control cam group and other levers operated by the cam engaging levers. The control lever group sets the components of the projector either to feed film forwardly or to rewind film and is locked in the forward feed film position and in the neutral position by a locking lever which is directly released by a member subjected to tension of the film. The control lever group includes only three cams.
Inventors
- 👤 M Kurasawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:24
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/14; G03B21/32; G03B21/43
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
465 words
An automatic film rewinding device for small movie projectors of the type having a film supply section, a projection lamp and components, including a driving motor, for driving the film in a forward film feed direction and a reverse film rewinding direction, said device cOmprising, in combination, a control cam group; externally accessible operating means operable to move said control cam group between forward film feed, neutral and reverse film feed positions; resilient means biasing said control cam group to its reverse film feed position; a cam group locking lever operatively associated with said control cam group and operable to releasably lock said control cam group in either said forward film feed position or said neutral position; a control lever group operatively associated with said control cam group and said components and operable in slaved relation by said control cam group, when the latter is moved to its forward film feed position, to set said components to feed a film forwardly; a lever mechanism operatively associated with said locking lever and engaged by a film secured at its trailing end to the shaft of a film supply reel, said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said locking lever to release its locking of said control lever group for movement of said control cam group, by said resilient means, to its reverse film feed position to move said control lever group to set said components to feed the film in a reverse rewind direction to effect automatic rewinding of the film; and a holding member operable to hold and lock said control lever group in the forward film feed position; said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said holding member to release its locking of said control lever group; said lever mechanism comprising a rotatably mounted shaft and a release lever secured at one end to said shaft to rotate therewith, said release lever having a cam surface, adjacent is free end, engageable with an end of said locking lever and having a projection at its free end engageable with said holding member; said shaft being rotated, responsive to such tensioning of the film, to swing said release lever in a direction effecting movement of said locking lever to the cam group release position and to effect movement of said holding member in a direction to release its locking of said control lever group; said cam surface being a curved cam surface extending in the direction of movement of said release lever but eccentric to said shaft; said locking lever being pivoted intermediate its ends and carrying a roller engageable with said cam surface.
Claim 2
Dependent Claim
465 words
An automatic film rewinding device for small movie projectors of the type having a film supply section, a projection lamp and components, including a driving motor, for driving the film in a forward film feed direction and a reverse film rewinding direction, said device cOmprising, in combination, a control cam group; externally accessible operating means operable to move said control cam group between forward film feed, neutral and reverse film feed positions; resilient means biasing said control cam group to its reverse film feed position; a cam group locking lever operatively associated with said control cam group and operable to releasably lock said control cam group in either said forward film feed position or said neutral position; a control lever group operatively associated with said control cam group and said components and operable in slaved relation by said control cam group, when the latter is moved to its forward film feed position, to set said components to feed a film forwardly; a lever mechanism operatively associated with said locking lever and engaged by a film secured at its trailing end to the shaft of a film supply reel, said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said locking lever to release its locking of said control lever group for movement of said control cam group, by said resilient means, to its reverse film feed position to move said control lever group to set said components to feed the film in a reverse rewind direction to effect automatic rewinding of the film; and a holding member operable to hold and lock said control lever group in the forward film feed position; said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said holding member to release its locking of said control lever group; said lever mechanism comprising a rotatably mounted shaft and a release lever secured at one end to said shaft to rotate therewith, said release lever having a cam surface, adjacent is free end, engageable with an end of said locking lever and having a projection at its free end engageable with said holding member; said shaft being rotated, responsive to such tensioning of the film, to swing said release lever in a direction effecting movement of said locking lever to the cam group release position and to effect movement of said holding member in a direction to release its locking of said control lever group; said cam surface being a curved cam surface extending in the direction of movement of said release lever but eccentric to said shaft; said locking lever being pivoted intermediate its ends and carrying a roller engageable with said cam surface.
Claim 3
Dependent Claim
465 words
An automatic film rewinding device for small movie projectors of the type having a film supply section, a projection lamp and components, including a driving motor, for driving the film in a forward film feed direction and a reverse film rewinding direction, said device cOmprising, in combination, a control cam group; externally accessible operating means operable to move said control cam group between forward film feed, neutral and reverse film feed positions; resilient means biasing said control cam group to its reverse film feed position; a cam group locking lever operatively associated with said control cam group and operable to releasably lock said control cam group in either said forward film feed position or said neutral position; a control lever group operatively associated with said control cam group and said components and operable in slaved relation by said control cam group, when the latter is moved to its forward film feed position, to set said components to feed a film forwardly; a lever mechanism operatively associated with said locking lever and engaged by a film secured at its trailing end to the shaft of a film supply reel, said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said locking lever to release its locking of said control lever group for movement of said control cam group, by said resilient means, to its reverse film feed position to move said control lever group to set said components to feed the film in a reverse rewind direction to effect automatic rewinding of the film; and a holding member operable to hold and lock said control lever group in the forward film feed position; said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said holding member to release its locking of said control lever group; said lever mechanism comprising a rotatably mounted shaft and a release lever secured at one end to said shaft to rotate therewith, said release lever having a cam surface, adjacent is free end, engageable with an end of said locking lever and having a projection at its free end engageable with said holding member; said shaft being rotated, responsive to such tensioning of the film, to swing said release lever in a direction effecting movement of said locking lever to the cam group release position and to effect movement of said holding member in a direction to release its locking of said control lever group; said cam surface being a curved cam surface extending in the direction of movement of said release lever but eccentric to said shaft; said locking lever being pivoted intermediate its ends and carrying a roller engageable with said cam surface.
Claim 4
Dependent Claim
465 words
An automatic film rewinding device for small movie projectors of the type having a film supply section, a projection lamp and components, including a driving motor, for driving the film in a forward film feed direction and a reverse film rewinding direction, said device cOmprising, in combination, a control cam group; externally accessible operating means operable to move said control cam group between forward film feed, neutral and reverse film feed positions; resilient means biasing said control cam group to its reverse film feed position; a cam group locking lever operatively associated with said control cam group and operable to releasably lock said control cam group in either said forward film feed position or said neutral position; a control lever group operatively associated with said control cam group and said components and operable in slaved relation by said control cam group, when the latter is moved to its forward film feed position, to set said components to feed a film forwardly; a lever mechanism operatively associated with said locking lever and engaged by a film secured at its trailing end to the shaft of a film supply reel, said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said locking lever to release its locking of said control lever group for movement of said control cam group, by said resilient means, to its reverse film feed position to move said control lever group to set said components to feed the film in a reverse rewind direction to effect automatic rewinding of the film; and a holding member operable to hold and lock said control lever group in the forward film feed position; said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said holding member to release its locking of said control lever group; said lever mechanism comprising a rotatably mounted shaft and a release lever secured at one end to said shaft to rotate therewith, said release lever having a cam surface, adjacent is free end, engageable with an end of said locking lever and having a projection at its free end engageable with said holding member; said shaft being rotated, responsive to such tensioning of the film, to swing said release lever in a direction effecting movement of said locking lever to the cam group release position and to effect movement of said holding member in a direction to release its locking of said control lever group; said cam surface being a curved cam surface extending in the direction of movement of said release lever but eccentric to said shaft; said locking lever being pivoted intermediate its ends and carrying a roller engageable with said cam surface.
Claim 5
Dependent Claim
420 words
An automatic film rewinding device for small movie projectors of the type having a film supply section, a projection lamp and components, including a driving motor, for driving the film in a forward film direction and a reverse film rewinding direction, said device comprising, in combination, a control cam group; externally accessible operating means operable to move said control cam group between forward film feed, neutral and reverse film feed positions; resilient means biasing said control cam group to its reverse film feed position; a cam group locking lever operatively associated with said control cam group and operable to releasably lock said control cam group in either said forward film feed position or said neutral position; a control lever group operatively associated with said control cam group and said components and operable in slaved relation by said control cam group, when the latter is moved to its forward film feed position, to set said components to feed a film forwardly; a lever mechanism operatively associated with said locking lever and engaged by a film secured at its trailing end to the shaft of a film supply reel, said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating state of the film supply, directly moving said locking lever to release its locking of said control lever group for movement of said control cam group, by said resilient means, to its reverse film feed position to move said control lever group to set said compOnents to feed the film in a reverse rewind direction to effect automatic rewinding of the film; a holding member operable to hold and lock said control lever group in the forward film feed position; said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said holding member to release its locking of said control lever group; a rotatable shaft having said cam group secured thereto adjacent one end thereof; said operating means including an operating knob secured to the other end of said rotatable shaft and externally accessible; said components of the projector including a clutch and a clutch operating lever; said cam group consisting of three axially adjacent cams each engaged by a respective first control lever; and second control lever pivoted intermediate its ends and having a first arm engageable with said clutch operating lever and a second arm engageable with one of said first control levers and movable in slaved relation with the latter.
Claim 6
Dependent Claim
420 words
An automatic film rewinding device for small movie projectors of the type having a film supply section, a projection lamp and components, including a driving motor, for driving the film in a forward film direction and a reverse film rewinding direction, said device comprising, in combination, a control cam group; externally accessible operating means operable to move said control cam group between forward film feed, neutral and reverse film feed positions; resilient means biasing said control cam group to its reverse film feed position; a cam group locking lever operatively associated with said control cam group and operable to releasably lock said control cam group in either said forward film feed position or said neutral position; a control lever group operatively associated with said control cam group and said components and operable in slaved relation by said control cam group, when the latter is moved to its forward film feed position, to set said components to feed a film forwardly; a lever mechanism operatively associated with said locking lever and engaged by a film secured at its trailing end to the shaft of a film supply reel, said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating state of the film supply, directly moving said locking lever to release its locking of said control lever group for movement of said control cam group, by said resilient means, to its reverse film feed position to move said control lever group to set said compOnents to feed the film in a reverse rewind direction to effect automatic rewinding of the film; a holding member operable to hold and lock said control lever group in the forward film feed position; said lever mechanism, responsive to tensioning of the film in the film supply section in the terminating stage of film supply, directly moving said holding member to release its locking of said control lever group; a rotatable shaft having said cam group secured thereto adjacent one end thereof; said operating means including an operating knob secured to the other end of said rotatable shaft and externally accessible; said components of the projector including a clutch and a clutch operating lever; said cam group consisting of three axially adjacent cams each engaged by a respective first control lever; and second control lever pivoted intermediate its ends and having a first arm engageable with said clutch operating lever and a second arm engageable with one of said first control levers and movable in slaved relation with the latter.
Claim 7
Dependent Claim
65 words
An automatic film rewind device, as claimed in claim 2, including a pair of spaced fixed contacts controlling an energizing circuit for said driving motor; and a circuit closure means secured to rotate with said shaft and operable, upon movement of said control knob in either direction from its neutral position, to interconnect said fixed contacts to complete the energizing circuit for said driving motor.
Claim 8
Dependent Claim
66 words
An automatic film rewind device, as claimed in claim 2, in which said control lever group includes a pivoted power source lever; a pair of fixed spaced contacts controlling an energizing circuit for said projection lamp; and a circuit closer on said power source lever operable, upon movement of said control knob to the forward film position, to interconnect said contacts to energize said projection lamp.
Claim 9
Dependent Claim
85 words
An automatic film rewind device, as claimed in claim 2, including a film pressing plate; and a horizontally movable support member for said film pressing plate; said control lever group including a pressing plate operating lever engaged with said support member and operable, responsive to movement of said control knob to the forward film feed position, to move said support member to position said pressing plate in the path of film movement; said holding member holding and locking said support member in its operated position.
Claim 10
Dependent Claim
87 words
An automatic film rewind device, as claimed in claim 2, including a rotation limiting member secured to said shaft; said resilient means comprising a tension spring having an end secured to said rotation limiting member; a first fixed stop engageable by said rotation limiting member upon movement of said control knob to the forward film position; and a second fixed stop engageable with said rotation limiting member upon operation of said release means; said second fixed stop carrying resilient sleeve means engageable with said rotation limiting member.
Claim 11
Dependent Claim
61 words
An automatic film rewind device, as claimed in claim 2, in which said control cam group includes a disc cam formed with a cam slot; and a normal-reverse direction switching lever having a pin engaged in said cam slot; said switching lever controlling said driving motor to operate in either the forward film feed direction or the reverse film feed direction.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-05 | 1976-09-04 | 1977-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-05 | 1980-09-04 | 1981-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-05 | 1984-09-04 | 1985-03-06 | $7700.00 | Window Closed / Lapsed |