GB475079A - Portable projection screen - Google Patents
Portable projection screenInfo
- Publication number
- GB475079A GB475079A GB31990/36A GB3199036A GB475079A GB 475079 A GB475079 A GB 475079A GB 31990/36 A GB31990/36 A GB 31990/36A GB 3199036 A GB3199036 A GB 3199036A GB 475079 A GB475079 A GB 475079A
- Authority
- GB
- United Kingdom
- Prior art keywords
- screen
- lever
- link
- handle
- occupies
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
- G03B21/00—Projectors or projection-type viewers; Accessories therefor
- G03B21/54—Accessories
- G03B21/56—Projection screens
- G03B21/58—Projection screens collapsible, e.g. foldable; of variable area
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Overhead Projectors And Projection Screens (AREA)
- Projection Apparatus (AREA)
Abstract
475,079. Projection screens. GRUBER, P. L. Nov. 23, 1936, No. 31990. Convention date, Oct. 1. [Class 97 (i)] A portable screen 6 carried on a spring roller 7 in a box 4 is raised by toggle levers 11, 12 actuated by a manually operated handle 14 through a lever system comprising, for each of the levers 11, 12, a link 18 pivoted at 16 to the handle 14, and at 20 to a lever 24 pivoted at one end to a fixed pivot pin 28 and at the other to a link 26 connected to a pin 34 slidable in a slot 30 in the base and connected by a link 36 to the lower arm 12 of the toggle lever system. When the screen is closed the lever 14 occupies the extreme position shown in Fig. 3, the closing action causing stretching of springs 38, 39, connected at one end respectively to the sliding pins 34, 35 and fixed at their other ends to the box 4. To open the screen the lath 10 is first raised by means of the handle 9, the springs 38, 39 assisting this action, and the lever 14 is then rotated to the left in Fig. 1, until it occupies the extreme position opposite to that shown in Fig. 3, where the screen is erect. Alternatively the screen may be mounted on a board, and may be of canvas covered with a layer of glass beads.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE475079X | 1936-10-01 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB475079A true GB475079A (en) | 1937-11-12 |
Family
ID=6541804
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB31990/36A Expired GB475079A (en) | 1936-10-01 | 1936-11-23 | Portable projection screen |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB475079A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110007553A (en) * | 2019-04-01 | 2019-07-12 | 深圳市火乐科技发展有限公司 | A kind of curtain and optical projection system |
-
1936
- 1936-11-23 GB GB31990/36A patent/GB475079A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110007553A (en) * | 2019-04-01 | 2019-07-12 | 深圳市火乐科技发展有限公司 | A kind of curtain and optical projection system |
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