Improvements in or relating to photographic shutters / [Heinrich Ernemann].

  • Ernemann, Heinrich.
Date:
1903
Catalogue details

Licence: Public Domain Mark

Credit: Improvements in or relating to photographic shutters / [Heinrich Ernemann]. Source: Wellcome Collection.

    1/6
    \’ ° 3191 A.D. 1903 Date of Application, 10th Feb., 1903—Accepted, 12th Mar., 1903 COMPLETE SPECIFICATION. Improvements in or relating to Photographic Shutters. (A communication from Heinrich Ernemann, Directing Manager of Sckandauer- strasse 48, Dresden—A, in tlie Kingdom of Saxony, Empire of Germany.) I, Alfred Julies Boult, of 111, Hatton Garden, in the County of London, Chartered Patent Agent do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described and ascer¬ tained in and by the following statement; — /) This invention relates to that class of photographic shutter known as. roller- blind shutters with me blind made in two parts, in which the width of the slot can be adjusted from the outside m the following manner; The edge of one half blind is provided with bands or strings passing through eyes on the edge of the second half blind, which cords, or strings are secured to pulleys arranged at both 10 ends of the roller for the first half blind in such manner that when the shutter is working they rotate together with the roller, but when the width of the slot ’s being adjusted they are turned relatively to the roller, which remains stationary. This invention refers particularly to sucli a shutter in which the common spindle of the roller and of tlie two pulleys is. at the same time used for adjusting the 15 pulleys from the outside after they have been uncoupled from the roller by being moved in longitudinal direction. As in the shutter according to this invention the roller arranged between the pulleys has no handle projecting outside by means of which it could be held fast during the adjustment of the pulleys, the spindle of the roller uncoupled must »)q be fixed during the adjustment, in some other way. This in one of the objects of this invention and is attained by a part which is nan-rotatable and which is connected with the longitudinally movable spindle, engaging with a part con¬ nected to the roller. It is preferable to use a perforated or toothed disc or flange . connected with the roller and a pin connected with the spindle and engaging with 25 the holes or notches in the said disc. The invention further relates to a device for indicating the width of the slot, which is moved together with the pulleys, but is not affected by the rotation of the spindle during the working of the shutter. For this purpose the movable spindle is. provided with an absolutely fixed pinion permanently engaging with a 30 dial or with a toothed wheel connected to a pointer, but which is coupled to the spindle only when the latter is moved longitudinally whereby the roller is un¬ coupled. The invention finally relates to means for uncoupling the winding device from the spindle during tlie adjustment of the pulleys, so that the spindle can be 6h rotated in either direction. A roller blind shutter according to this invention is illustrated in the accom¬ panying drawing, in which Fig. 1 is an elevation, partly in section, Figs. 2 and 3 are respectively left and right hand end views, Fig. 4 shows separately, on an enlarged scale, the perforated disc on the spindle and Figs. 5 and 6 show ill 40 longitudinal and cross section the left hand end of the spindle, with the coupling for the pinion of the indicator. [Price 8d.]