Patent US4340198A successfully refreshed from Google Patents.
US4340198A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stand for a projection screen
Assignee: Mechanische Weberei GmbH
•
Filing: 1980-05-09
•
Granted: 1982-07-20
•
Expires: 2000-05-09
Abstract
Abstract A projection screen stand has a post which normally can be supported in an upright position, e.g. by legs in a tripod arrangement, and provided with a holder for a tube which receives the screen and from which the screen can be withdrawn. According to the invention, the holder has a dovetail recess or slot and the tube has a complementary fitting or tenon receivable in this recess and designed to enable the tube to be withdrawn readily from the holder and used independently of the post.
Inventors
- 👤 Helmut Meinunger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:47
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/58; F; F16; F16M; F16M2200/00; F16M2200/02; F16M2200/021; F16M2200/024
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
120 words
A projection screen assembly which comprises: a post; a holder mounted on said post and formed with a dovetail-like slot; a head of generally dovetail-like profile removably receivable in said slot; and a projection screen tube mounted on said head whereby said tube can be removed with said head from said post, said holder being mounted on a slotted sleeve, said slotted sleeve being provided with a male thread at one end having a frustoconical portion at said end, said assembly further comprising a locking sleeve having a female thread engageable with said male thread and a frustoconical portion adapted to clamp said slotted sleeve against said post, said sleeve surrounding said post and being slidable with said holders thereon.
Claim 2
Dependent Claim
120 words
A projection screen assembly which comprises: a post; a holder mounted on said post and formed with a dovetail-like slot; a head of generally dovetail-like profile removably receivable in said slot; and a projection screen tube mounted on said head whereby said tube can be removed with said head from said post, said holder being mounted on a slotted sleeve, said slotted sleeve being provided with a male thread at one end having a frustoconical portion at said end, said assembly further comprising a locking sleeve having a female thread engageable with said male thread and a frustoconical portion adapted to clamp said slotted sleeve against said post, said sleeve surrounding said post and being slidable with said holders thereon.
Claim 3
Dependent Claim
80 words
A projection screen assembly which comprises: a post; a holder mounted on said post and formed with a dovetail-like slot; a head of generally dovetail-like profile removably receivable in said slot; and a projection screen tube mounted on said head whereby said tube can be removed with said head from said post, said holder being formed with a cover swingable about the axis of said post for blocking said recess to prevent inadvertent withdrawal of said head from said recess.
Claim 4
Dependent Claim
80 words
A projection screen assembly which comprises: a post; a holder mounted on said post and formed with a dovetail-like slot; a head of generally dovetail-like profile removably receivable in said slot; and a projection screen tube mounted on said head whereby said tube can be removed with said head from said post, said holder being formed with a cover swingable about the axis of said post for blocking said recess to prevent inadvertent withdrawal of said head from said recess.
Claim 5
Dependent Claim
41 words
The assembly defined in claim 2 wherein said cover is formed on its surface turned toward said recess with a projection and said head is formed with a recess for receiving said projection and indexing said cover in a closed position.
Claim 6
Dependent Claim
55 words
The assembly defined in claim 3 wherein said head is provided with a pair of confronting disc-shaped elements, one of which is connected to said tube and the other of which is connected to a T-slot portion of said head and a bolt connecting said elements for relative rotation about the axis of said bolt.
Claim 7
Dependent Claim
79 words
The assembly defined in claim 4 wherein one of the elements is provided with a bolt and the other of the elements is formed with at least two recesses angularly spaced about the axis of said bolt by 90° for receiving the bulge of said one of said elements and indexing said tube selectively in a position in which said tube lies transverse to said post and in a position in which said tube lies parallel to said post.
Claim 8
Dependent Claim
83 words
The assembly defined in claim 2, claim 3, claim 4 or claim 5 wherein said holder being mounted on a slotted sleeve, said slotted sleeve being provided with a male thread at one end and having a frustoconical portion at said end, said assembly further comprising a locking sleeve having a female thread engageable with said male thread and a frustoconical portion adapted to clamp said slotted sleeve against said post, said sleeve surrounding said post and being slidable with said holders thereon.
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) | 1985-07-19 | 1986-01-18 | 1986-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-07-19 | 1990-01-18 | 1990-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-07-19 | 1994-01-18 | 1994-07-20 | $7700.00 | Window Closed / Lapsed |