GB345925A - Improvements in and connected with projection screens - Google Patents

Improvements in and connected with projection screens

Info

Publication number
GB345925A
GB345925A GB2757130A GB2757130A GB345925A GB 345925 A GB345925 A GB 345925A GB 2757130 A GB2757130 A GB 2757130A GB 2757130 A GB2757130 A GB 2757130A GB 345925 A GB345925 A GB 345925A
Authority
GB
United Kingdom
Prior art keywords
lid
box
screen
roller
secured
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
Application number
GB2757130A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to GB2757130A priority Critical patent/GB345925A/en
Publication of GB345925A publication Critical patent/GB345925A/en
Expired legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03BAPPARATUS 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
    • G03B21/00Projectors or projection-type viewers; Accessories therefor
    • G03B21/54Accessories
    • G03B21/56Projection screens
    • G03B21/58Projection screens collapsible, e.g. foldable; of variable area

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Transmission Devices (AREA)

Abstract

345,925. Projection screens. HUNTER, R. F., BLACKBURN, A., and NAGEL, H., 40, Doughty Street, London. Sept. 15, 1930, No. 27571. [Class 97 (i).] A projection screen A is carried by a spring roller B mounted within a box E, the free end of the screen being attached to a lid member H, and the lid and box being connected by a screen-stretching device which is housed within the box when the screen is not in use. The stretcher may comprise two struts L, K, the strut L being pivoted to the lid at O and provided with a pin P, or a roller, movable in a slotted guide Q secured in the box, and the strut K comprising two parallel bars pivoted at one end within the box and carrying, at the other end a pin M, or a roller, moving in a slotted guide N secured to the lid. A spring catch R engages the pin M to hold the screen in extended position, and may be released by a sliding finger-piece S carrying a cam T. The box is also provided with one or more notched projections I each engaging in a hole J when the lid is closed, and a slotted plate, sliding within the lid under spring action, and secured to the finger-piece S, may engage each notch to secure the lid in closed position. One of the blocks C forming bearings for the spindles of the roller B may be slotted so that the position of the spindle may be adjusted therein by means of a screw X to equalize the tension of the stretched screen.
GB2757130A 1930-09-15 1930-09-15 Improvements in and connected with projection screens Expired GB345925A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2757130A GB345925A (en) 1930-09-15 1930-09-15 Improvements in and connected with projection screens

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2757130A GB345925A (en) 1930-09-15 1930-09-15 Improvements in and connected with projection screens

Publications (1)

Publication Number Publication Date
GB345925A true GB345925A (en) 1931-04-02

Family

ID=10261783

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2757130A Expired GB345925A (en) 1930-09-15 1930-09-15 Improvements in and connected with projection screens

Country Status (1)

Country Link
GB (1) GB345925A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104455983A (en) * 2014-11-28 2015-03-25 海信集团有限公司 Screen levelness adjusting mechanism and projection display device
CN118131558A (en) * 2024-04-30 2024-06-04 深圳市宝溢显示技术有限公司 Quick-supporting screen

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104455983A (en) * 2014-11-28 2015-03-25 海信集团有限公司 Screen levelness adjusting mechanism and projection display device
CN118131558A (en) * 2024-04-30 2024-06-04 深圳市宝溢显示技术有限公司 Quick-supporting screen

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