US2186926A - Ratchet footage indicator for motion picture apparatus - Google Patents

Description

Jan. 9, 1940. c. .1. HUGHEY 2,186,926

RATCHET FOOTAGE INDICATC'R FOR MOTION PICTURE APPARATUS Filed Sept. 23, 1957 FIG.1.

Carter J. Hughey INVENTOR Patented Jan. 9, 1940 UNITED STATES PA ENT. OFFICE RATCHET FOOTAGE INDICATORFOR MOTION PICTUREAPPARATUS l Carter J. Hughey, Rochester, N. Y., assignor to Eastman Kodak Comp-any, Rochester, N. Y., a.

corporation. of New Jersey Application September 23, 1937, Serial No. 165,375

In Germany September 25, 1936 I 8 Claims.

respect to the footageindicator, the operation of the footage indicator-by the actuating means may be extremely critical and subject to failure iflthe actuating means is not precisely mounted within the apparatus casing and with respect to the footage indicator. I

The primary object of the present invention is the provision of a ratchet assembly comprising in combination an actuating means, adriven means, and an intermediate motion transmitting means which will operate to advance the driven means irrespective of any variations in positioning of the actuating means or in the actuating movement thereof.

Another object of the invention is the provision in a ratchet assembly of an intermediate motion transmitting means including a normally arcuate resilient portion, which arcuate portion is straightened by the action of the actuating means for advancement of the driven means.

A further object of the invention is the'provision of an intermediate motion transmitting means for a ratchet type of footage indicator in-,

cluding a pivotally mounted arm carrying an arcuate-spring portion which is intermittently straightened and permitted to return to arcuate position for intermittent advancement of akdrivenmeans having a plurality of teeth; V

Still another object of theinvention is the provision of an intermediatemotion transmitting means 'for a ratchet type of footage indicator and which means comprises a single spring member having one end engaging the teeth of' the footage indicator disc to prevent reverse movement thereof and having an arcuate portion at its other end for engaging a tooth of the indicator disc and which arcuate portion is intermittently straightened for intermittent advancement of the teeth on said disc. I

Other and further objects of the invention will be suggested to those skilled in the art by the following description.

The above and other objects of the invention.

are embodied in a ratchetassembly including the combination with an actuating means including an engaging portion, and a driven means having a plurality of teeth, of anintermediate motion transmitting means including a normally arcuate resilient portion located to engage the teeth of said driven means, arranged to be inter mittentlymoved by the action of the engaging portion of said actuating means into a straightened position for advancement of a'tooth of said driven means and then permitted normally to return to arcuate form for engagement with an adjacent tooth on said driven means.

Reference is hereby made to the accompanying-drawing wherein similar reference characters designate similar elements and wherein:

Fig. 1 is a side elevation of amotion picture apparatus equipped with a ratchet type of footage indicator accordingto the invention, the casing of said apparatus being broken away for better illustration .of the details. of the ratchet construction.

Fig. 2 is an enlarged detail of the ratchet assembly of Fig. 1 illustrating conditions just prior to operation of the intermediate motion transmitting means.

Fig. 3 is a similar detail to enlarged; scale but showing the intermediate motion transmitting I means with the arcuate resilient portion thereof in extended or straightened position.

Fig. 4 isa side elevation of a'modified form of the ratchet type of footage indicator according to the invention.

Although the improved intermediate motion transmitting means. for a ratchet. assembly, ac-

may be mounted within said casing and includes an eccentrically located engaging portion. Such an actuating means may comprise a driving member, suchas a spring motor drum I2 which is rotatable about a shaft l3 extending between the side walls I 0 of the casing. Spring motor drum l2 contains a spring 12" which has oneend attached to the drum l2 and the other end, not

shown, connected to the shaft'l3. .A pin I4 is" The driven means is movably mounted within said casing and may comprise an indicator disc l5 which may be pivotally mounted on side walls H] by a pin 20. Teeth l6 of a definite and substantially uniform pitch extend around the periphery of disc [5. A series of footage numerals ll may be engraved on indicator disc l5'and may be visible from the exterior of the apparatus through the window l3 provided in said side wall [0.

According to the preferred form of the invention, a resetting knob E9 on the exterior of side wall in may be connected to pin 28 for resetting of the footage indicator. Also a holding pawl to prevent retrograde movement is preferably supplied although it should be understood that the same result may be accomplished by sulficient frictional resistance in the mounting for the driven means or in the pivotal support for disc i5. Such a holding pawl, see Fig. 1, may comprise a wire spring 2! mounted on the interior of side wall ii] by a screw 22, having one end engaging the teeth 16 of disc 15 to prevent reverse rotation thereof and having the other end encircling a pin 23 also on the-interior of side wall Ill.

The intermediate motion transmitting means intermittently transmits the movement of the actuating means to the driven means. The outstanding feature of the present invention is the provision of a resilient member in such intermediate motion transmitting means and which resilient member is preferably provided as an arcuate resilient portion to be extended or straightened by the action of the engaging portion on the actuating means to advance, tooth by tooth, the driven means.

According to the preferred form of the invention, the intermediate motion transmitting means may comprise an arm 24 which is pivotally mounted by a pin 25 upon the interior of side wall it! and which includes an arcuate spring portion 26 having one end connected to or integral with arm 2 3 and having a free end 26 engaging the peripherial teeth 56 of disc l5. Arm 24 may also be provided with a curved edge 24 which is engaged by the pin it on spring drum l2 so that upon rotation of drum [2 in the direction of the arrows, see Figs. 2 and 3, arm 24 is rotated in a clockwise direction, see Fig. 3.

Said arcuate spring portion 26 normally assumes a curved position as shown in Fig. 2 and in which normal position the distance between the free end 26' and the point of attachment to the arm 24, or the chord subtending the arc of spring portion 25, is indicated by the dimension a. As the pin 14 moves in a clockwise direction, the cainming action between said pin I4 and the ctu'ved edge 25' of arm 24 results in rotation of said arm 24 and in a straightening or extension of said arcuate spring portion 26. This condition is illustrated in Fig. 3. It should also be noted that during the straightening or extended position of arcuate portion 26, the distance between the free end 26 and point of attachment to arm 24 is represented by the dimension D which equals approximately the length of the arc of spring portion 26. Such extension of portion 26 is sufficient to advance a tooth IS on the disc 15 a distance greater than or exceeding the pitch of said teeth it. In other words, the dimension b is greater than the dimension is plus the pitch of the teeth IE or the difference between the length of the arc of arcuate spring portion 26 and thec'hord subtending that are greater than the pitch but less than twice the pitch of a tooth on disc l5. As a result, disc [5 will be rotated angularly a distance of one tooth.

After pin I4 passes out of engagement with arm 24, the resiliency of arcuate spring portion 26 will return it to its normal position and so that the free end 26 thereof comes into engagement with the adjacent or succeeding tooth IS on disc l5.

According to another form of the invention, the holding pawl and arcuate spring portion of theintermediate motion transmitting means are simultaneously provided. A single spring member, such as a spring wire 2'1, is mounted on the interior of side wall I!) by studs 28 and 29. Said spring wire 27 has one end 30 in continuous engagement with the teeth l6 of disc id to prevent retrograde or reverse movement thereof. The intermediate portion 3! is curved around said stud 28 and bears against stud as for mounting of spring wire 21 on the interior of side wall Iii. An arcuate spring portion 32 is formed from the other end of spring wire '2'! and has a free end 32' abutting against one of the teeth (8 on disc l5.

As before, upon rotation of spring drum I2 in the direction of the arrow, see Fig. 4, the pin l4 strikes against the arcuate spring portion 3?. to extend or straighten the same and to move one of the teeth It a distance slightly exceeding the pitch of such tool. After pin M moves beyond arcuate spring portion 32, said spring portion returns to its normal position and is curved sufficiently to come into engagement with the adjacent or succeeding tooth IS on disc 55. During this return of arcuate spring portion 32 to its normal condition, the other end 30 of spring 2'! acts to prevent any reverse rotation of disc I 5 by reason of such return of the arcuate spring portion 32.

From the foregoing disclosure of the invention it will be understood that the advancement of the driven means a distance exceeding the pitch of a tooth is determined primarily by the curvature of arcuate spring portions and 32'. As a result, variations in the eccentricities of pin it on spring drum l2 or variations in the mounting of spring drum 2 with res ect to arm 24 or spring wire 21 to increase or decrease the deflection of arcuate spring portions 26 or 32 will not cause a corresponding variation in the advancement of a tooth it. In other words, the straightening or extension of arcuate portions 26 or 32 will occur sufficiently to advance a tooth iii of the driven meansupon angular movements of arm 24 or small deflections of arcuate spring portion 32 and greater angular movements of arm '24 or deflections of spring portion 32 will not-alter the advancing action of such arcuate spring portions correspondingly but, as long "as there is enough angular movement of arm 24 or deflection of spring portion 32 to advance a tooth l6, any additional movements by reason of inaccuracies of manufacture or assembly do not affect the operation of the intermediate motion transmitting means to result in inoperativeness of the ratchet assembly.

Since many variations of the invention are possible, the scope of the invention is not to be limited in any respect by the present disclosure but is defined in the appended claims.

Having now particularly described my invention what I desire to secure by Letters Patent of the United States and what I claim is:

1 In'a ratchet assembly, the combination with a driven member movably mounted and having a plurality of teeth of a predetermined pitch, of a motion transmitting means for advancing said driven member tooth by tooth and including an arcuate resilient member having a curvature such that the difference between the length of the arc of said resilient member and the length of the chord subtending that are is greater than the pitch of one tooth but less than twice the pitch of a tooth on said driven member.

2. In a ratchet assembly, the combination with a driven member movabiy mounted and having a plurality of teeth of a predetermined pitch, of a motion transmitting means for advancing said driven member tooth by tooth and including an arcuate resilient member having a curvature such that the difference between the length of the arc of said resilient member and the length of the chord subtending' that are is greater than the pitch of one tooth but less than twice the pitch of a tooth on said driven member, and a movable actuating means for intermittently moving said motion transmitting means to cause movement of said arcuate resilient member from its arcuate condition to an approximately chordal position.

3. In a ratchet assembly, the combination with an actuating 'means movably mounted and including an engaging portion, and a driven means also movably mounted and having a plurality of teeth or" a predetermined pitch, of an intermediate motion transmitting means including a normally arcuate resilient portion having a free end for engaging the teeth of said driven means, arranged to be intermittently straightened by the action of the engaging portion of said actuating means, adapted upon such straightening to advance a tooth of said driven means a distance greater than the pitch but less than twice the pitch of said tooth, and then returning to normal position for engagement with an adjacent tooth of said driven means.

l In a ratchet assembly, the combination with a driving member rotatably mounted and ineluding an engaging portion which is eccentrically located, and a driven member rotatably mounted and having a plurality of teeth of a predetermined pitch, of an intermediate motion transmitting means including a normally arcuate resilient portion located to engage the teeth of said driven means, arranged to be intermittently straightened by the action of the eccentric engaging portion of said driving member, adapted by such straightening to be extended for advancing a tooth of said driven member a distance exceeding the pitch but less than twice the pitch of said tooth, and then after disengagement from said engaging portion returning to normal position for engagement with the succeeding tooth on said driven member- 5. In a ratchet assembly, the combination with a driving member rotatably mounted and including an engaging portion which is eccentrically located, and a driven, member rotatably mounted and having a plurality of teeth of a predetermined pitch, of a single spring member having one end engaging the teeth on said driven member to prevent reverse rotation thereof, and having an arcuate portion at the other end for engaging a tooth of said driven member and which arcuate portion is intermittently engaged and straightened by said engaging portion to advance said tooth a distance exceeding the pitch thereof.

6. In a ratchet type footage indicator for motion picture apparatus, the combination with a driving member rotatably mounted and including an eccentrically located engaging portion, and an indicating member rotatably mounted and having a plurality of teeth of a predetermined pitch, of an intermediate motion transmitting member including an arm pivotally mounted and located intermittently to be rotated by the engaging portion of said driving member and including an arcuate spring portion for engaging the teeth of said indicating member, intermittently straightened by the intermittent rotation of said arm, and adapted upon said straightening to be extended a distance exceeding the pitch but less than twice the pitch of said tooth for corresponding advancement of said indicating member.

7. In a ratchet type of footage indicator for motion picture apparatus, the combination with a casing, a spring drum rotatably mounted within said casing and carrying a pin eccentrically located, an indicator disk rotatably mounted on said casing and having a plurality of teeth, and a holding pawl on said casing for engaging said teeth to prevent retrograde movement of said disk, of an intermediate member rotatably mounted on said casing, having a portion adapted intermittently to be actuated by said pin for periodic rotation of said member, and including an arcuate spring portion engaging a tooth on Q1 said disk, which arcuate portion is straightened by the rotation of said intermediate member to advance said disk a distance greater than the pitch but less than twice the pitch of said tooth;

and which arcuateportion normally returns said intermediate member to an initial position with said arcuate spring arm in engagement with the succeeding tooth on said disk.

8. In a ratchet type of footage indicator for motion picture apparatus, the combination with a casing, a spring drum rotatably mounted within said casing and carrying a pin eccentrically located, and an indicator disk rotatably mounted on said casing and having a plurality of teeth, of a single spring member intermediately mounted on said casing, having one end engaging the teeth on said indicator disk to prevent reverse rotation thereof, and having an arcuate portion at the other end for engaging a tooth of said disk,

' which arcuate portion is intermittently engaged

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