US1906818A

US1906818A - Cinematographic apparatus

Info

Publication number: US1906818A
Application number: US511518A
Authority: US
Inventors: Seufert Friedrich
Original assignee: Individual
Current assignee: Individual
Priority date: 1930-02-04
Filing date: 1931-01-27
Publication date: 1933-05-02
Anticipated expiration: 1950-05-02

Description

"May 2,1933. s u 1,906,818

0 INEMATOGRAPHI C APPARATUS Fild Jan. 27, 1931 Q 2 Sheets-Sheet 1 INVENTbR. 5 z M 1. flwcmm A TTORNEYS.

'May 2, 19 33, F. S EUFERT 1,906,318

CINEMATOGRAPHIC APPARATUS Filed Jan. 27, 1931 2 sums-shat 2 L77 J$WJ6 -w INVEN TOR. W

A TTORNEYS.

' first named modification.

for en the aforementioned cam groove 12". aid means 'may be constructed as follows Fi 2 and so spaced, that always two of said ro ers will tangentiall engage one edge of said cam groove 12" an the other tangentially engage the opposite edge of said groove 12'.

If therefore the cam body 12 is rotated the mirror 26 will slowly move from the left hand position dotted lines) to the right hand position (ful line) in 300 of a complete revolution of said body and then quickly return to the initial position in the last The speed of movement of the mirror 26 must be exactly equal to the speed of the feed of the film F so that the projection of the ima e onto the screen throu h the lens L be ren ered steady. This spec is controlled by the cam groove 12 and the driving means therefor.

If desired the shutter 40 may be geared to gear 20 and rotated in synchronism with the other apparatus, being so timed as to cut 01? the light from lens L during the return movement of the mirror 26 In the modification'shown in Figs. 46 the construction is essentially the same as in the But in place of a direct coupling between cam 12 and the mirror 26 I provide a linkage. Here the

cam follower

30, 31, 32, 33 which is identical with that of the first named modification, is formed on the end of an arm 34? of adouble armed lever 34. The said lever is pivoted at 34 and the second arm 34 thereof pivotally enga es at 35 a link bar 35. Said link bar pivotally engages a stud 36 provided on downwardly projecting member 37 attached to the movable mirror 26. The cam 12 is supported on the shaft 11 rotata'ol borne in a separate compartment 10 of t e housing 10. Said cam is driven by means of a gear 38 and a gear 39 on the sprocket drum shaft 20'.

The principal of operation is the same as, before except that the intermediary linkage between the cam follower and the movablemirror enables a rearrangement of the elements to eliminateiunnecessary gearing and cheapen the construction without impairing the effectiveness of the device.

It is obvious that the mirrors may be. re-

placed by risms if desired.

The in e of operation is as follows If for instance a ray of light R strikes the film F at a point z, and is transmitted to the leg 25' of the fixed mirror 25 it strikes the latter at :12 and is reflected to the leg 26 striking the latter at w. Thence it is reflected to leg" 26" striking the latter at m and thence to leg 25 striking the latter at 0: and is reflected thereb through lens L onto the screen (not shown If the film moves from point a: to point 3 the ray of light that passes through point a: would now pass through point 3 This ray R owing to the simultaneous displacement of mirror 26 now strikes leg 25 at y is reflected to leg 26 at y, thence to leg 26 at y, thence to leg 26! to which coincides with 0: so that it will be reflected through the lens L on same line as before.

It will be seen that this will occur only if the displacement of the mirror 26 is in synchronism with the feed of the film so that the image will remain stationary despite the motion of the film. r

The chronism is best obtained by rendering ih: displacement of the mirrors positive through my novel cam construction and follower means. I

My device may modified in man other ways and I do not wish to be limite to the details shown and described.

=What I claim is 1. In a cinematographic apparatus having an image feed and equalization means for said image feed, a cylinder having a cam groove for controlling said means, a cam groove follower comprising a set of at least three rollers arranged in triangular fashion on a rotatable support and concentrically with respect to the axis of rotation of said support,- the spacing between said rpllers being so admeasured that at least two rollers will tangentially bear against one side of said groove and at least one against the op osite side of said groove,said groovebeingso s aped as to control the speed of the movement of said equalization means to'be always equal to the speed of said image feed.

2. In a cinematographic apparatus as per claim 1, in which said sup rt for said rollers comprises a disk rotata' le upon a central axis and is formed with pins 'parallel to said axis and rotatably bearin said rollers.

In testimony whereof afiix my signature.

FRIEDRICH SEUFERT.