US1812212A - Motion picture projector - Google Patents

Description

June 30, 1931. w. H. MEYER MOTION PICTURE PROJECTOR Filed Aug. 1, 1925 2 Sheets-Sheet l June 30, 1931. w. H. MEYER MOTION PICTURE PROJECTOR Filed Aug. 1, 1925 2 Sheets-Sheet 2 are I Patented June 30, 1 931 UNITED STATES PATENT OFFICE WILLIAM H. MEYER, OF ST. LOUIS, MISQOURI money 210mm]; rneenemcn Application nee August 1, 1925. mm 1%.,

This inven'cion relates to imprevemenm in quilting; cniy e chem threw cf ebcn'fi; ten in meticn piccnre projecting machines and mere twenty feet, equipped with e, ienep havpereiculafly m the non-theatrical type 01E ing a cendiepcW-er which is low enengh be projecting machines which are adapted for permit *fee chewing cf stii l pictures Wichii e in wheels churches, business eem ciishout any dengec cifignieing ccherwise ruin- 55 en'zs, etc @ne of (me deslrabie features 01' mg either e 3 1 safety .UjQCiJlHQ machine 1e be ecie non-1i ,mmeme film ready for use Iv Beth c ne ehcve men'lzicne we jiectcze new a eq 1 shutter eh ine' ize, called 565 trevei ghc h in c when such cf inca Mme eaec cei simplifies .2 w p ynve ed, lamps of projecting cieelmbie cc run the iceicw meme ca? e e'bili cases ctunng 131 is demi- & machine er other e comm; of

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em, 03% ebeuc .000 week a mere v11 e pro ine is rest 01 sceticnarye, 1

ms 15 cf the film, eicner between i (J a at amount 01: been W. p Tra- TGVOL i e nutter 1S wavcivn" and as 45 "1*emcuntc-ftheheecreysand cy simmer which pcsiiiened iaeh -eet will biiste? and destiny ii: tween the iemp 1 1d film su JWPESSfiS the heat lei; we The latter type cf film rays en the film when prcjectcr is use& cc e extencin ncn-theecriceipm stop e61 or a still is being shown, it can jecccrs as emeeeure of safety. readfly be seen that there is a tendency for We 59 Pecjeciaere which are used for purposes re the picture on the screen 130 be about the same and whereby the revolving shutter acts as its 5 the kind of material used in the safety shutter.

In my Patent No. 1,413,050, issued April 18, 1922, I providefor a revolving shutter which is operable on the light rays when the projector is run at normal speed and which is automatically folded and inoperable on the light ra s at speeds below normal or when the mac ine is stopped for showing a still picture. This shutter at no time obstructs the light rays when the projection is run below normal speed or when stop ed. In the above patent I also provide or a safety shutter having a translucent material which suppresses the heat rays projected on the film a sufficient amount to prevent injury to the later. The safety shutter is operable by means of a governor and the revolving shutter is a governor in itself as it is controlled by a sprin' and by centrifugal force acting on each bla e. Both of these shutters act independently and are adjusted separately and it requlres considerable skill to adjust them so that they act at the same time to prevent, as much as possible, any noticeable difference between the brightness of the picture on the screen when the safety shutter ecomes operable on the light ra s and therevolving shutter becomes inopera 1e, or vice versa.

The main object of the present invention is to provide for direct cooperating means between the safety and revolving shutters whereby the safety shutter becomes operable on the light rays the instant the revolving shutter becomes inoperable or vice versa;

own governor and also as a governor for the safety shutter and provides for a single adjustment for this combination of shutters so as to eliminate the element of skill required where the shutters are adjusted separately. I Another object of the resent invention is to provide an improved cm of safety shutter which is cooperable with the light rays and with a foldable revolving shutter.

Another object is to provide a'safety shutter havin either a single or a plurality of.

erforate metal lates the perforations bemg so arranged t at the center heat rays in .the beam of light will be suppressed a reater percentage relative to the percentage t at the outer heat rays are suppressed, and also that this percentage be gradually decreased a safe amount from the center rays to the outermost so that the maximum amount of light will be provided to show a still picture. "A further object is to provide a safety shutter having a heat ray suppressing safety means which is suitable for nitro-cellulose film, and which can interchange with another heat ray suppressing safety means which is suitable for acetate-cellulose film; thus providing for the maximum amount of light within safe limitsfor a still picture for either type of film.

Other and further objects will appear in the specification and be specifically pointed out in the appended claims, reference being had to the accompanying drawings, exemphfying the invention, and in which Figure 1 is a plan view of the projector and lamp housing,.being shown in section.

Figure 2 is a side elevation of Fig. 1 in which the lamp housing is shown in section.

Figure 3 is a transversevertical section galienlapproximately on the line IIIIII of Figure 4 is an enlarged front elevation of the fire shutter.

Figure 5 is an enlarged vertical section taken on the line VV of Fig. 4.

Figure 6 is an enlarged elevation of the fire shutter showing a modification of the form of perforated material used therein.

- Referring by numerals to the accom anyin drawings 1 designates a frame-wor for the support of the mechanism of the machine and extended transversely and horizontally therethrough is a shaft 2, and secured to one end of said shaft is a turning crank 3, and secured to the opposite end of said shaft is a spur gear 4, and in mesh with said gear is a pinion 5 which is mounted on the shaft 6 of the film sprocket 7. In mesh. with the spur gear 4 is a pinion 8, which is mounted on a horizontally disposed shaft 9, and secured on said shaft is a worm wheel 10, which is in mesh with a worm 11 which is secured to.a longitudinally disposed shaft 12.

Slidably and loosely mounted on the shaft 12 is a grooved collar 13, and extended from said collar is a yoke 14, said yoke on one side bein pivotally connected at 15 to an ear 16 which is extended at right angles from the blade 17 of a revolving or intermittent shutter 18, said blade 17 at its opposite end having a right angularly bent ear 19 extended therefrom, said ear 19 and car 16 being swingably mounted on a pin 20, said pin being supported in a U-shapedmember 21, which is rigidly secured to one side of a collar 22, said collar being rigidly secured to the shaft 12 by the pin 23.

Borne by the U-shaped member 21 in opposing disposition to the pin 20 is a pin 24, and mounted on one end of said pin is an ear 25 which is extended at right angles from the blade 26 of the shutter 18, said ear 25 corresponding to the ear 16 of the shutter 17 and extended at right angles from said blade 26 in opposite disposition from the ear 25 is an ear 27 which is mounted on the opposite end of the pin 24, said car 27 corresponding I to the ear 19 of the shutter 17. Mounted on III each of the pins 20 and 24 is a coil spring 28, one end of a respective spring being secured to a respective ear 16 and 25 through the hole 160; in the ear 16 and a corresponding hole 25a in the car 25, whereas the opposite end of a respective spring bears against the U-shaped member 21,.

Engaged within the groove of the collar 13 is a clutching portion 29 of a slidable bar 30, said bar being mounted on the bearing bracket 31 of the shaft 12 and is held in slidin position thereon by the screws 32 and depen ed from the intermediate portion of the bar is an ear 33 bearing a pm 34, said pin being for engagernept with the bifurcated end of the arm 35 of a rock lever36, said lever being pivoted at 37 to the frame-work 1..

Borne by the frame-work 1 is a horizon tally disposed projecting tube 38, and arranged rearwardly of said frame-work is a lamp housing 39 having its projecting tube 40 in alinement with the tube 38, and ar ranged in said tube 4:0 is a condensing lens ll and disposed between said lens and the light emitting bulb i2 is a fire shutter 43, and depended from the frame it of said shutter is an arm having its lower end rigidly secured to a shaft 46 which is supported in a bearing 47 which is extended from the lamp housing 39, and rigidly secured to said shaft on the outside of said housing is a lever 48 to which is secured a link 49, the depending end of said linlr being pivotally securedvto the arm 50 of the rock lever 36.

The fire shutter 43 is provided with a pair of spaced apart apertured or perforated plates 51 which are secured in the frame 44, the apertures or perforations in the center of each of said plates being miniature in size, whereas the apertures arranged outwardly of the center of the plates aregradually increased in size As the heat rays in a concentrated beam of light in the usual project- 4 ing machine are of the greatest intensity, at

the center of the beam and greatly increase,

in intensity from the center to the outermost rays, this manner of gradually increasin the size of the perforations in the plates 51 1 rom the center to the outer edges of the plates, provides a means for suppressing all of the heat rays to a degree which gives as nearly as possible an even amount of heat rays through the entire transverse area of the light beam so as to provide the maximum amount of li ht that can be safely projected on the film when the latter is stationary.

In the operation of the mechanism, when the crank 3 is turned, ower will be transmitted to the pinion 5 rom the spur gear 4 and to the intermittent film driving sprocket 53 through the train of gearin thereto, and.

in which the'picture film 52 wi 1 be caused to operate downwardly through the ath of light projected'from the tube 4O oft e lamp housing 89, said spur gear 4 alsovcausing the shaft 9 to be revolved and the worm Wheel 10 I mounted on said shaft will become active on the worm 11 of the shaft 12, and inasmuch as the collar 22 to which the ll-shaped member 21 is secured is rigidly fastened to said shaft 12, the revolving shutter 18awill be revolved thereby.

l Vhen the mechanism is being operated at about the required speed, the blades 17 and 26 of the shutter 18, which are normally held inwardly by the tension of the springs 28, will be forced outwardly by centrifugal action and inasmuch as the shaft 12 parallels the projecting tube 38 at a distance therefrom, each blade 17 and 26 will alternately pass through the light beam projected through said tube, the purpose of said blades being well known.

As the blades 17 and 26 of the revolving shutter 18 are thrown. outwardly, the collar 13 and yoke is borne thereby, will be moved outwardly along the shaft 12 towards the shutter 18, and inasmuch as the bar 30 is in engagement with the groove of said collar by the clutching portion 29, said bar will also be moved outwardly as well as the arm 35 of the roclr lever 36, and the arm 50 of said rock lever will be moved upwardly and the link 49 secured thereto will cause the lever 48 on the shaft it to move, and inasmuch as the fire shutter 43 is extended from said shaft, said shutter 43 will be thrown out of the path of the li ht rays projected through the tube 40 of the lamp housing 39 to the position shown in dotted lines in Fig. 3.,

When the mechanism is slowed down or stopped, the springs 28 will become active on respective ears 16 and 25 of the'blades 17 and 26 of the revolving shutter 18, thereby drawing said blades inwardly to their normal or ion neutral positions, and in which said cars 16 and 25 will be moved rearwardly and in consequence the collar 13 will also be moved rear, wardly, and the bar 30 will cause the rock lever 36 to be returned to its normal position, thereby throwing the fire shutter back into its normal position into the projectinglight rays thereby protecting the film from theheat units contained in the projecting light ra s.

dhe type of plates 51 used in the fire shutter 43 and the size of perforations in said plates 1 shutter 43, in which the revolving shutter is I the governor for the fire shutter, said revolving shutter eliminating the heretofore separate and individual governor used in cooperation with a fire shutter.

The movement of blades 17 and 26 from closed position (as shown in Fig. 2) to open pos1t1on as shown by the dotted line is substantially instantaneous as the blades revolve in a very small circle at the center when closed and in a much larger one when open. It can readily be seen that there is a much greater amount of centrifugal force acting on the blades when in open position than in closed position and that this force increases rapidly as the blades are opening and that the relative amount of increase is much greater than the increase in speed of rota tion of shutter. Likewise, when the blades are closing, the action of springs 28 tend ,to

quicken the closing movement as they willtend to overcome the centrifugal force acting on the blades more rapidly as the blades are moved closer to the center of shaft. It can readily be seen that since the shutter 43 is cooperably connected to blades 17 and 26 and that there is a substantially instantaneous alternate change between the two shutters relative to their transverse positioning in the path of light and that therefore there will be no noticeable change in the light on the screen when the shutters are alternating their positions.

The disclosure in Fig. 6 is a modification of the fire shutter in which a body of wiremesh material such as a screen 54 is used, and 1n order to reduce the mm of the meshes in the central portion of the material, a patch portion of material 55 is located against or f adjacent the central portion of the material body 54. This arrangement of applying a patch portion to the mesh body, will serve the same purpose as does the minute apertures formed in the plates of the shutter 43.

In the preferred form of my invention,

3 the perforated shutter 43 is positioned bep be positioned between the of said fire shutter being smaller than the surrounding perforations.

2. A motion picture projector providedwith a' fire shutter which is perforated over its entire face, the perforations in the center of said shutter being small and graduating in' size as they extend outwardly from the center of said shutter.

3. In a motion icture projector, the combination of a mova le fire shutter, a revolving shutter having a pivotal blade structure, a shaft to which said revolving shutter is rigidly secured, an element cooperable with the blade structure of said revolving shutter slidably mounted on said shaft, and means actuated by said element for moving said fire shutter into the projecting light ray of said projector.

4. In a motion picture projector, the combinationof a movable fire shutter, and a revolving shutter having a pivotal blade structure, a shaft to which said revolving shutter is secured, a collar slidably mounted on said shaft adapted to be actuated by said revolving blade structure, a bar connected to said collar, and linkage connected to said bar and said fire shutter.

5. A motion picture projecting machine having a movable fire shutter and a revolving shutter, said revolving shutter having a cutting-off element which is adapted to pass through the light my projected from the machine when said shutter 1s operating at substantially normal speed, said element adapted to be positioned out of the path of li ht when said revolving shutter is operating elow said normal speed, and cooperable means connected to said fire shutter and said revolving shutter for operating said shutters in synchronizing relation.

6. A motion icture projecting machine having a mova e fire shutter and a revolving shutter, said revolving shutter having a plurality of cutting-off elements which are adapted to pass through the light ray projected from the machine when said shutter is operating at substantially. normal speed, said elements adapted to be positioned out of the path of light when said revolving shutter is operating below normal speed or when said shutter is stopped, and cooperable means connected to said fire shutter and said revolv ing shutter for operating said shutters in synchronizing relation.

7. A motion picture projecting machine having a movable fire shutter and a revolving shutter, said revolving shutter having a cutting-off element which is adapted to pass through the light my projected from the machine when said revolving shutter'is operating,said element adapted to be sitioned out of the ath of light when said revolving shutter 1s sto ped, and means cooperably connected to sai revolving shutter and said fire shutter whereby said shutters will operate in synchronizing relation with respect to one another.

8. A motion having a movab ing'shutter, a shaft disposed parallel to the projecting ray ,oflight of said machine forpicture projectin machine fire shutter an a revolv- 4 the support of said revolving shutter, said revolving shutter having a cutting-elf element which is adapted to pass through the light ray of said machine when said revolving shutter is operating, said element adapted to be positioned out of the path of light when said revolving shutter is inoperative on light path, and connecting means cooperably disposed between said shutters for operating shutters in synchronizing relatiom 9., The combination of a source of light and means for projecting a light beam therefrom, a plate positioned transversely in said beam, said plate adapted to Withstand the heat rays of said beam and having numerous perforce tions in substantially its entire area, the crforations the center portion of said p ate being s aller than the perforations in the outer portion thereof.

10 The combination ot a source or" light, means for projecting a light beam therefrom and a plate positioned transversely in said beam, said plate adapted to withstand the heat rays in beam and having numerous perforations therein which are smaller in size in the portion of the plate upon which said. heat rays greater intensity of said beam are directed ll. llhe combination of source of light and means for projecting a light beam there from, a plate disposed transversely of said. beam having perforations forming passageways :tor transmitting part of the light rays of said through said plate, the portion of said beam which is directed upon one side of plate adjacent thereto having heat rays greater intensity at one portion of its cross sectional area than at another, the disposition or? the sizes of the perforations of said plates comprising a means for suppressing the light rays in said beam so as to rovide a substantially uniform amount of cat over the entire cross sectional area of the portion of said beam directed from the other side of said plate and adjacent thereto.

12. A motion picture projector having a lamp and a film, means for directing a beam of light from said lamp to said film, a shutter including a plate adapted to withstand the heat rays in said beam, said plate being positioned transversely of said beam and substantially covering the cross sectional area thereof and having perforations in substantially its entire area, the erforations in the center portion of said p ate being smaller than the perforations in the outer portion thereof.

13. In a device of the class described, a lamp, a film, means for directing a. light beam from said lamp to said film, a shutter having a perforated plate positioned in said beam between sdid lam and said film when the device is operating slow a normal speed or stopped, sald shutter adapted to be posihaving a movable tire shutter and a revo t tioned away from the beam when the device is operated at a normal speed, the perform tions in one portion of said plate being smaller than the perforations in another T tion of said plate.

14. In a device of the class described, a lamp, a film, and means for directing a light beam from said lamp to said lilm, a shutter having a perforated plate positioned in said beam between said lamp and said film when the device is operating below normal speed, said plate adapted to be positioned from said beam when the device is oper ted at a normal speed, said shutter provi means for suppressing a portion of the heat rays in said beam so as to give a substantially uniform distribution of heat over sub-- stantially the entire transverse area of beam at and adjacent to said 15. A motion picture ro ectin mac shutter, said revolving shutter having a c tingoli' element which is adapted to through the light ray projected from the machine when said revolving shutter is ating, said element adapted to be positioned out of the p ath of light when said revolving shutter is operating either below a norms speed or when stopped, and means cooper: ably connected to said revolving shutter said lire shutter whereby said shutters will operate in synchronizing relation with. re spect to one another 16., In a motion picture projector, the .CQEL." bination of a lamp, means for directing a light beam -from said lamp, a picture element positioned transversely of said light beam, a shutter having collapsab-le li ht cuttingofi means adapted to pass into and out of J l path of said light beam when the cutting;- od means is in open position during the when the shutter is operating at substantially normal speed, said cutting-oil means adapted to remain out of the path of the light beam when in a closed position when said shutter is operating below a normal speed or when stopped, partial heat suppressing adapted to bepositioned transversely of the light beam between said lamp and said picture element when said shutter is operating be low a normal s eed or when sto pod and adapted to be positioned out of the light beam when said shutter is o crating at substantially normal speed, an means governed by said cutting-off means connected to said shutter and said heat suppressing means for op erating said heat suppressing means in synchronizing relation with said cutting-oil means.

17. In a motion picture pro eotor, the combination of a. lamp, means or directing a light beam from said lamp, a. picture element positioned transversely of said light beam, a shutter having light cutting-of means adapted to pass into and out of the path of said light beam when said shutter is operating at substantially normal speed, said cut tin -ofl:' means adapted to remain out of the pat of said light beam when said shutter is operating below a normal speed or when stopped, partial heat suppressing means adapted to be positioned transversely of said light beam between said lamp and said picture element when said shutter is operatin below a normal speed or when stopped an adapted to be positioned out of the path of the ight beam when said shutter is 0 erating at substantially normal speed, an means governed by sald cutting-oil means and connected to said shutter and said heat suppressing means for operating said heat suppressin means in synchronizmg relation with said cutting-off means.

18. The combination of a source of light directed u on an object and a perforated plate positloned between the source of light and the object transversel of the light beam from said light source, t e arrangement of the perforations and contours and sizes of said perforations of said plate comprising a means for suppressing the heat rays in the light beam so as to provide a substantially uniform amount of heat over the entire cross sectional area of the light beam at and adjacent to said object.

WILLIAM H. MEYER.

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