US531012A - thornton - Google Patents

Description

J.- E. THORNTON 8v E. PICKARD.

' PHOTOGRAPHIG PLATE HOLDER Patented Dec. 18, 1894.

INVENTORS.

dd'faa. fifa/LM (Model.)

No. 53l,012.

v WITNESSES UNITED STATES PATENT OFFICE.

JOHN E. THORNTON AND EDGAR PICKARD, OF ALTRINCHAhl, ENGLAND.

PHOTOGRAPHIC-PLATE HOLDER.

SPECIFICATION forming part of Letters Patent No. 531,012, dated December 18, 1894.

Application tiled January 18, 1894. Serial Nol 497,327. (Model.)

To all whom ir) may concern:

Be it known that we, JOHN EDWARD THORN- TON and EDGAR PIOKARD, both of Altrincham, in the county of Chester, England, have invented certain new and useful Improvements in Plate-Holders for Photographic Cameras, of which the following is a specification.

This invention relates to plate holders for the sensitive plates by which they are placed in and removed from photographic cameras and is designed to render such holders more eiiicient in holding the plates and the operation of inserting the plates therein and withdrawing them therefrom, more convenient.

It consists essentially in constructing that part of the frame into which the plate is placed with a fixed ledge on every side between which the plate is placed and fitting closely thereto with a rabbet or under cut recess at the top edge and a movable strip or spring bar at the bottom to slide over the fixed ledge to form a groove or recess at the bottom edge, a spring or springs being placed below the same and with a spring or springs to press the plate outward when released and render it easy of being handled or taken hold of.

It will be fully described With reference to the accompanying drawings in which as an example a double slide is illustrated.

Figure 1, is a front elevation partly in section with the slide and sensitive plate removed. Fig. 2, is a transverse sectional elevation with the sensitive plate and slide in position at one side and the slide removed and the plate partly removed at the other side. Fig. 3, is a sectional plan with the plate and slide in position at one side and removed at the other side.

The external frame A is made in any convenient Way with the corners dovetailed or otherwise secured together and is provided with slides B, a central diaphragm or division plate'C, sensitive plates D and light excluding strips F pressed outward by springs e all constructed of any ordinary or convenient shape.

We construct the frame A with a fixed ledge d at each side of the space into which the plate D is to be inserted. At the right and left of the space the fixed ledge a is formed by the sides of the frame. At the top it is formed by the rabbet orgroove G out in the frame A, which also provides a projection g under which the edge of the plate can be inserted. At the bottom it is formed bythe lixed piece or bar K. In front of and sliding over the fixed piece or bar K We place a spring bar E. The spring bar E is capable of moving to and fro over the surface of the fixed piece or bar K and when pushed outward from the trame A forms a groove or recess for the bottom edge of the plate D. Vhen the plate is in the holder the normal position of the spring bar E is that shown in Fig. l. It is held in that position by the spring L and the pins M. The ends of the spring bar E slide in grooves m cut in the sides of the frame A.

On the center diaphragm or division plate O We place a spring or springs H which hold the sensitive plate D against the projection g and the spring bar E to prevent it moving or shaking and to hold it in focus. Then the spring bar is moved past the edge of and out of contact with the plate D and level with the edge of the iixed bar K the springs H cause the sensitive plate to move or spring outward at the bottom edge so thatit may be easily taken hold of.

The outer edge of the spring bar E maybe if desired beveled to the correct angle so that by pressing the plate D down upon it it will be caused to slide back and permit ofthe plate being inserted between the rigid ledges a.

To insert the plate D in position in the holder the top edge is first passed behind the projection g and inserted in the groove G. The lower edge is pressed down compressing the springs H. The spring bar E is drawn back and the edge of the plate is brought to position in front of the edge of the fixed bar K. The spring bar E is then moved back to its normal position by the spring L covering the edge of' the plate and holding it in position. The plate is released and removed by the reversal of' these movements.

Ve are aware thatplate holders have been constructed with sliding spring bars which abut against the edges of the plates to adapt them to variations of size and to secure the plates in position and such we do not claim.

What we claim as our invention, and desire to protect by Letters Patent, is-

1. In a plate holder the combination with IOC) the frame A provided with rigid ledges a the slide B, the light excluding strips F, the projecting piece g forming the groove G of the fixed bar K against the edge of which the sensitive plate D rests and the spring bar E which slides upon the surface of the xed bar K and overlaps the edge of the plate to hold it in position substantially as described.

2. In a plate holder for photographic canieras the combination of the frame A the slide B the central division plate C the light eX- -cluding strip F the projection g forming the groove G to receive the top edge of the plate v D the ixed bar K forming a rigid ledge for the bottom edge of the plate to rest against, the spring bar E sliding over the surface of the fixed bar K and overlapping the edge of the plate to secure it in position the spring L to move the spring bar in one direction the pins M to control the movement of the spring bar and the springs H to prevent movement of the plate and force it outward when released substantially as described.

In testimony whereof We have signed our names to this specification in the presence of two subscribing witnesses.

J. E. THORNTON. EDGAR PICKARD.

Witnesses:

J. OWDEN OBRIEN, CHAS. OvnNDALn.

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