US1458303A - Arrangement of centering the film in the gate of cinematograph projectors - Google Patents

Description

June 12, 1923. 1,458,303

S. KL ICHARSKI ARRANGEMENT OF CENTERING THE FILM IN THE GATE OF CINEMATOGRAPH PROJECTORS Filed Aug. 31 1921 3 Sheets-Sheet 1 June 12, 1923.

. S. KUCHARSKI ARRANGEMENT OF CENTERING THE FILM IN THE GATE OE CINEMATOGRAPH PROJECTORS 5 Sheets-Sheet 2 Filed Aug. 31 1921 d 2 1 b d w .9 .9

5 0 5: I I .7: y E

June 12, 192.3.

ARRANGEMENT OF CENT l ,458-,303 s. KUCHARSKl BRING THE FILM IN THE GATE OF CINEMATOGRAPH PROJECTORS 5 Sheets-Sheet 3 Filed Aug. 51, 1921 Patented June 12, 1923.

UNITED STATES PATENT orrlcs.

' mnanemnnr or cnn'rnnme 'rrm FILMIN THE GATE 0] CINEKA'IOGBAPH.PBO-

JECTOBS.

Application filed August 31,1921. Serial No. 497,808.

(GBAMID 'UITDEI THE PROVISIONS OF THE A01. 01' [A1011 3, 1921, 41 STAT. 13., 1318.)

my concern: that I, Smmsmos KUCHAR- near Berlin, De-rning the film of cimematograph apparatus in the correct position 1n the window of the gate. In cinematograph apparatus in which the film constantly moved forward, it is known on makin this adjustment to avoid a displacement 0 the whole device for feeding the film by imparting to the feed wheel a tempo film has attained the right position in the film window. For this purpose the film feed wheel is provided with a toothed wheel which has, one tooth less than a toothed wheel of its driving shaft with which it is connected through a sliding coupling. In the normal working a toothed wheel engaging constantly with both of these toothed wheels rotates about the wheels without rotation about its axle, so that the feed wheels are driven directly from their axles and at the same speed. If the rotating toothed wheel is held fast, it receives through the driving shaft and the feed wheel, a rotation about its axle and transmits the rotation of the shaft with somewhat greater velocity to the feed wheel.

For cinematograph apparatus with Maltese cross feeding motion a device of this kind has not previously been used, because it was generally accepted that the masse formed by the intermediate toothed wheel and its mounting arts, as well as the device for holding th1s toothed wheel static-nary, could not be held in rotation by the Maltese crosswithout disturbing the whole drive. The present invention depends on the recognition that in many cases it is possible to hold the rotating masses so easily that they will not interfere with the normal working when used in combination with the Maltese cross device.

The arrangement can be so constructed a citizen of Germany, resid have invented cerrary acceleration until. the

that the intermediate toothed wheel in the normal workingis not engaged with the toothed wheel of the driving shaft and the feedmg wheel and. is only inserted for the purpose of adjusting the film. Consequently, the intermediate toothed wheel remains at rest in the normal working and onl rotates about its axle when the film 1s mg adjusted. A circular rotational movement is, therefore, avoided in this constructlon and the membersof the film adjusting device all concerned in the normal working.

The drawings illustrate several modes of construction according to the invention.

Figs. 1 and 2 show one constructional form in two difi'erent views,

F1g 3 is a View of an other form in the direction of the optical axis of the apparatus towards'the source of light, and

F g. 4 a side view of this form. t Fig. 5 shows particulars of the arrangement of Figs. 3 and i.

The feed wheel 0. (Figs. 1 and 2) as in known devices is mounted loosely on the drivlng shaft hand is connected therewith only through sliding couplings 0, comprising friction rings which are pressed between the feed wheel a and a disc d secured to the shaft 5 and a toothed wheel e also secured to this shaft. On the feed wheel a there is a toothed wheel f which has one tooth less than the opposite toothed wheel 6.

Ad ac/ent to the toothed wheels 6 and f there 1s a toothed wheel h mounted on a pivoted lever g the width of the wheel It being such that it can engage at the same time with both toothed wheels 8 and f. It may in the normal working, be held out of engagement with the toothed wheels 8 and f for example by a spring e' so that the rotation of the driving shaft 3; is transmitted by the friction coupling 0 directlyto the feed wheel a.

If during the working an adjustment of the film setting in the window is; necessary, the wheel h is moved from the outside of the apparatus by means of a hand wheel k, a lever Z and a link on into gear with the wheels e and f. is transmitted from the shaft b to the feed wheel a over the wheels e,hand f instead of by the friction coupling and since the wheel f has one tooth less than the wheel e, the feed The frictional movement lit) wheel a receives a smaller acceleration than the shaft 5 which advances until the film has taken up its correct position in the window. The hand-wheel k is then released and the spring 5 brings the wheel it again out of enga ement.

lie the arrangement according to Figs. 3 to 5 ti is the frame of the apparatus and h an axle led through the nave oi" the frame, said axle being driven by the toothed wheel at, pertaining to the gearing 101' the optical synchronizing of the moving picture. in feeding the iilm step by step, for instance a Maltese cross may be substituted for the wheel I @n said spindle is fixedly secured by means of a pin on the one hand the toothed wheel a and on the other hand the disc 0?. Between both parts and d) the shifting roller 0; is arranged to move freely on the spindle 5 however under a rather great resistance by way of friction caused by the discs al and d These consist of leather or any other suitable material.

Fixedly secured to the shifting roller is a toothed wheel 7", possessing the same numher of teeth and losing oi the same size as the toothed wheel c. @n the pin 0 d) mounted on the frame, a fork is provided, ireely rotatable thereon consisting of two rigidly connected parts g g and cartying, on both its ends a pair of toothed wheels it, it and $2. it each. Both parts oil each pair oi toothed wheels as rigidly connected to each other, and one wheel in each pair is provided with one tooth more than the other.

A lever it provided with a handle it is freely turnable on a pin mounted on the frame and the spring 0 tends to lreep this lever in a horizontal position. By means of the connecting rod m the lever n is connected to the fork g g in such a manner, that through the horizontal position of said lever, the torlr is likewise kept in a-horizontal position, that is to say in such a way, that neither the pairof toothed wheels h it nor the pair k becomes active.

With the arrangement of the lever n and the springs r and r as shown in Fig. 5 the lever n may be more reliably held in horizontal position and thus also that of the fork 9 g is warranted in so far as both springs referred to are bearing with considerable force and tension upon the extension 8 provided on the frame of the apparatus,and that each change of position of the lever it out of its central position must be efiectcd under a certain expenditure of ower. In. the construction as illustrated in ig. 4 the central position is somewhat unreliable, since each change from that position will commence with an expenditure of ower at zero; it may be efiected, however, m a somewhat simpler manner than that shown in Fig. 5.

If the lever n by means of the handle at isshitted from its horizontal position, then either the pair of toothed wheels h h become active or the pair 71. 71. Now the wheels of each pair differ by a tooth and the run of the shifting roller will be accelerated or slowed down w an the pair of wheels becomes operative, in accordance as to whether for instance the wheel h possesses one tooth more or less than the wheel k so that gradually a correct centering of the picture in the gate and in consequence on the screen, is eiiccted.

It is obvious, that it merely depends on the proper disposition of the toothed wheels 71. h on the one hand and if, it on the other hand in respect of the ratio of transmission in View of the toothed wheels 7, 6, so that the action of the one air of wheels will accelerate the movement of the shifting roller. while the action of the other pair will slow it down, in accordance as to whether the picture is displayed too high or too low on the screen.

it is further obvious, that if no use is made of this latter advantage, one pair of toothed wheels ti it or 72 77? would sufill] fice, but that during the working of the apparatus frequent adjustment would become necessary, the one or the other loop of the film would steadily grow shorter and be torn in case of inadvertence by the operator. Such occurrence is entirely avoided owing to the two pair of wheels, on the one hand. in that through such arrangement it is rendered possible either to accelerate or to slow down the movement of the shifting roller, on the other hand, and secondly, because in the case of the picture being a little out of its proper position on the screen, only such small error isto be corrected by a proper op eration of the described device; but with only one pair of toothed wheels that work in one direction only, the film must be adjusted under circumstances almost by the entire length of a picture.

I claim:

1. ln mechanism of the class described, means for adjusting the film in the window, comprising in combinaton with the intermittently moving feed wheel and the drive shaft for the film, of a normally operative frictional connection between the feed wheel and the driving shaft for the film, and manually operated means for positively connecting the feed wheel with the film drive shaft to cause said wheel and shaft to move at different speeds.

2. In mechanism of the class described, means for adjusting the film in the window, comprising in combination with the intermittently moving feed wheel and the drive shaft for the film, of a normally operative frictional connection between the feed wheel and the driving shaft for the film, and menu.

ally operated .means for itively connect ing the feed wheel and i; e film drive shaft to accelerate or retard the movement of the shaft with respect to the ieed wheei.

' 3. In a device for adjusting film in the Window of cinemeto eph apparatus, the combination with ihe intermittently moving feed wheel and the film driving shaft, of two wheels of unequal. size, connected with the feed wheel and film driving shaft res oziivel an intermediate wheel for coup ing the rst two wheels and means for moving the intermediate wheel into and'out of 0perative position.

4. In a device for adjusting the film in the window of oinematograph apparatus, the

combination wiih fiche inicermietenily moviiig feed wheel driving shaft for aim fiim, of fcoothed wheeis of diameter eon mooted with the feed WhfiQl and with like diving ieepeciaive ly and e, plumlii of pairs of Tigidiy eomieefaed (soothe-d Wheeis mounted tabs eitemexteiy engaged with the 'lhemioy to drive the feed with oeoeieieied or e, retarded mofLion wiafiii to the i eed Wheel In testimony whereof K have ofixed my signa'iuwe in presence of two witnesses.

STANEESLAUS KUCHARSIUD Awm HAUemIANN,

Gwe mv SWEET. i

Images