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US4969733A Expired / Lapsed US ⏱️ 0.0 years remaining

Foldable portable overhead projector

Assignee: Dukane Corp
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Filing: 1989-10-02
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Granted: 1990-11-13
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Expires: 2009-10-02
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Abstract

Abstract A portable foldable overhead projector includes a housing having a front opening communicating with an interior cavity, and a bottom aperture communicating with the cavity and closable by a pair of pivoting doors which, when open, support the housing on support legs and accommodate movement of a mirror inside the housing between stowed and use positions. In the use position the mirror reflects light from a source through a transmitting stage in the top wall of the housing which forms a pivoting door to provide further access to the cavity. A mast pivots along the outside of the housing and carries a foldable projection head assembly on a rack and pinion mechanism. When the mast is lowered the rack and pinion can be operated to move the folded projection head assembly through the front opening into the cavity for storage.

Inventors

  • 👤 Charles B. Jewison

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 06:18
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/14; G03B21/30; G03B21/132

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 135 words
A portable foldable overhead projector comprising: a housing containing a light source, said housing having an opening communicating with a cavity therein, transparency stage means on said housing for transmitting light from said source along a light path, mast means mounted on said housing externally thereof for movement between raised and lowered positions, projection means carried by said mast means and disposable in said light path when said mast means is in its raised position for directing and focusing an image onto a remote viewing surface, and drive means for moving said projection means relative to said mast means through said opening between an unstowed position disposed outside said housing and a stowed position disposed in said cavity within said housing while said mast means is mounted in its lowered position externally of said housing.
Claim 2
Dependent Claim 135 words
A portable foldable overhead projector comprising: a housing containing a light source, said housing having an opening communicating with a cavity therein, transparency stage means on said housing for transmitting light from said source along a light path, mast means mounted on said housing externally thereof for movement between raised and lowered positions, projection means carried by said mast means and disposable in said light path when said mast means is in its raised position for directing and focusing an image onto a remote viewing surface, and drive means for moving said projection means relative to said mast means through said opening between an unstowed position disposed outside said housing and a stowed position disposed in said cavity within said housing while said mast means is mounted in its lowered position externally of said housing.
Claim 3
Dependent Claim 33 words
The projector of claim 1, wherein said housing includes a top door carrying said transparency stage means and movable between open and closed conditions for providing access to the interior of said housing.
Claim 4
Dependent Claim 19 words
The projector of claim 1, wherein said mast means is pivotally movable between the raised and lowered positions thereof.
Claim 5
Dependent Claim 18 words
The projector of claim 3, and further comprising means for locking said mast means in its raised position.
Claim 6
Dependent Claim 30 words
The projector of claim 1, wherein said projection means includes reflector means and lens means mounted for movement between a folded configuration for stowage and an unfolded configuration for use.
Claim 7
Dependent Claim 21 words
The projector of claim 1, wherein said drive means includes means for moving said projection means longitudinally of said mast means.
Claim 8
Dependent Claim 14 words
The projector of claim 6, wherein said drive means includes rack and pinion means.
Claim 9
Dependent Claim 104 words
A portable foldable overhead projector comprising: a housing containing a light source, said housing having an aperture therein, transparency stage means on said housing for transmitting light, reflective means mounted in said housing for movement between a stowed position disposed entirely within said housing and a use position extending outwardly from said housing through said aperture, said reflective means in the use position thereof reflecting light from said source along a path through said transparency stage means, and projection means carried by said housing externally thereof in a use configuration along said path for directing and focusing an image onto a remote viewing surface.
Claim 10
Dependent Claim 104 words
A portable foldable overhead projector comprising: a housing containing a light source, said housing having an aperture therein, transparency stage means on said housing for transmitting light, reflective means mounted in said housing for movement between a stowed position disposed entirely within said housing and a use position extending outwardly from said housing through said aperture, said reflective means in the use position thereof reflecting light from said source along a path through said transparency stage means, and projection means carried by said housing externally thereof in a use configuration along said path for directing and focusing an image onto a remote viewing surface.
Claim 11
Dependent Claim 19 words
The projector of claim 8, wherein said reflective means is pivotally movable between the stowed and use positions thereof.
Claim 12
Dependent Claim 28 words
The projector of claim 8, wherein said aperture is formed in the bottom of said housing, said reflective means dropping through said aperture to the use position thereof.
Claim 13
Dependent Claim 37 words
The projector of claim 10, wherein said housing includes support legs providing clearance between the bottom of said housing and an associated underlying support surface to accommodate movement of said reflective means to the use position thereof.
Claim 14
Dependent Claim 30 words
The projector of claim 10, wherein said reflective means includes stop means engageable with said housing when said reflective means is in its use position for limiting the movement thereof.
Claim 15
Dependent Claim 15 words
The projector of claim 8, and further comprising an auxiliary light source in said housing.
Claim 16
Dependent Claim 36 words
The projector of claim 13, and further comprising carriage means supporting said light sources and shiftable between first and second positions for moving said light sources respectively into position for directing light to said reflective means.
Claim 17
Dependent Claim 157 words
A portable foldable overhead projector comprising: a housing containing a light source, said housing having an aperture therein, transparency stage means on said housing for transmitting light, reflective means mounted in said housing for movement between a stowed position disposed entirely within said housing and a use position extending outwardly from said housing through said aperture, said reflective means in the use position thereof reflecting light from said source along a path through said transparency stage means, projection means carried by said housing externally thereof in a use configuration along said path for directing and focusing an image onto a remote viewing surface, and door means mounted on said housing for movement with respect thereto between open and closed conditions for respectively opening and closing said aperture when said reflective means is disposed in its stowed position, said door means in the open condition thereof accommodating movement of said reflective means between its stowed and use positions.
Claim 18
Dependent Claim 157 words
A portable foldable overhead projector comprising: a housing containing a light source, said housing having an aperture therein, transparency stage means on said housing for transmitting light, reflective means mounted in said housing for movement between a stowed position disposed entirely within said housing and a use position extending outwardly from said housing through said aperture, said reflective means in the use position thereof reflecting light from said source along a path through said transparency stage means, projection means carried by said housing externally thereof in a use configuration along said path for directing and focusing an image onto a remote viewing surface, and door means mounted on said housing for movement with respect thereto between open and closed conditions for respectively opening and closing said aperture when said reflective means is disposed in its stowed position, said door means in the open condition thereof accommodating movement of said reflective means between its stowed and use positions.
Claim 19
Dependent Claim 16 words
The projector of claim 15, wherein said aperture is formed in the bottom of said housing.
Claim 20
Dependent Claim 33 words
The projector of claim 15, wherein said door means includes a pair of doors pivotally movable between the open and closed conditions thereof and cooperating in their closed condition to close said aperture.
Claim 21
Dependent Claim 53 words
The projector of claim 17, wherein said aperture is formed in the bottom of said housing, each of said doors carries support legs engageable with an associated underlying support surface when said doors are disposed in their open condition for providing clearance between the bottom of said housing and the underlying support surface.
Claim 22
Dependent Claim 19 words
The projector of claim 15, and further comprising means for latching said door means in the closed condition thereof.
Claim 23
Dependent Claim 19 words
The projector of claim 15, and further comprising means for retaining said door means in the open condition thereof.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-11-12 1994-05-14 1994-11-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-11-12 1998-05-14 1998-11-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-11-12 2002-05-14 2002-11-13 $7700.00 Window Closed / Lapsed

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