US2521178A - Automatic brake for springtensioned take-up reels - Google Patents

Description

sept- 1950 A. MELETT] 2,521,178

AUTOMATIC BRAKE FOR SPRING-TENSIONED TAKE-UP REELS Filed March 22, 1946 2 Sheets-Sheet l JOAN A. MELETTI Sept. 5, 1950 2 sheets shee't 2 Filed March 22, 1946 INVENTOR.

Patented Sept. 5, 1950' AUTOMATICBR'AKE FOR SPRING TENSIBNEB TAKE-UP- REE-LS Adolph. Moletth Philadelphia, Pal, assignor' to Vacuum- Cleaner Corporation at America, Ehiladolphin, 2a., a corporation of Pennsylvania. Application More! 22, 1946, Serial Nor 656,382: 5 Claims. (Cl. 242-107) The pnesent imtention relates: to oergtam immovements in. spningtensioned and other take up: reels. and it relates; more. particnionly to novel automatic. mechanism for spring-wound; cord-controlled take-uoreelsz.

An: object. of the; ptesent invention to provide: a. new and improved construction for snrmg-e tensionedr other take-up:- reels or thro'liise. additional ohiect. of. the pnesent invention to. provide novel braking: mechanism; for spring;- wound cord -contnolizedi talks-up reels; or the; like:v Still another object of the: present to; provide: automatic braking mechanism for sprimtwvound cord-controlled; tail'm-upl reels on the: like: whenehy the braking forces is. proportional to the. w'md-up speed of the thereby to; prevent. excessive. speed ofv notation. of; the heel. during. operation. A fiurther ob;- ject of the present. invention: is to: provide; onto? matic centrifugally-actuaitad braking mecmnism; for a: real; or: the; like.

Gthenobjects and admntages: oi the. present; inventiom are apparent: in. the. following die-tailed. description, appended claims: and: accompanying" drawings.

In my Patent. 391,840,. I have: disclosed a novel springs-wound cordscontnol'led inlse-upv rest for: electric. cords or the. like whereby the cord. can.he-.manua,1lyunwound, toany suitable: extent:

from azspri'ng tensioned; reel provided with latching mechanism which will hold the cord: in its. extended position. but which can be. released. by at. outward mill the: cordsm asto. permit the.- reei". to; be. tuned by its: spring. continuously. to. refiwindi. the: curt.

While the construction. shown. in my Patent $391,841) has: proven: highly satisfactory; in use, it has been. tunnel that. under. certain. circum-- stances nequiring" strong; spring-alction or. great. cord-lengths reel tends to; re-wind at ex- Qessive; speeds, When-A this: occurs, there is some danger of; ther onemton beingstnuck by: the plug on: other, connection. at the free end of the. cordg, if. heis, not coronal...

Aocordingly-.. the; present. invention; contemr z. centrifugally-aotuated by the speed oi rotation oi the reel so as, to apply a. restrainingionce when: the speed of the. reel. becomes. excessive; the: braking force varying; directly: with the speed oi rotation of the reel.

For the purposeoi illustrating the inoentiom; there is shown. in the; accompanying dmw-ingsone form. thereof: which is: at present preterred although it is: to, be understood. that the: various instrumentalities. of which the; invention consists can be variously arranged. and organized and. that. the invention notlimitedto the precise; arrangements.- and organizations: oi; the. instrmmentslities as; herein. shown and described.

Ref-coring; to the accompanying; drawings in; which like neterence. characters indicate partsthroughout:

Figure. L. represents a,- view riartly inelevation and partly in cross-section of one embodiment of the present invention.

Figure 2 represents at neduced vertical cross- SEGblOIlWl-l View. enerally along; the l-inea 2--2- 015 Figure. L. V

Figure 3. represents enlarged fragmentanp side elevational' view looking. generally in. the direction: ot the; arrows? 3.--3 of: Figure. 2..

Figure L represents a, cross-sectional view, gemersllv along, the line. 43-4. of. Figure 3 showing the; reel-latching mechanism in; looking position; andshowing the: brake mechanism in nonsmokeing position.

Fig-ore; 5} representsview. genera-11y similan: to that of Figure: 4 but showing. the: position of: the pour-ts while. the reel. is; rewinding ago-inst the restraint. of: thebrake;.

In the embodiment of Figures 1 $0953.13 haves Sh'Q'WH13/L reel; generally: similar to: that disclosed inmy Patent 2-,.39fl,8.4(i', which includes a. centmll drum: huh I. uponi which an. insulated electric: cord: 8.-is.w.oi1nd The hub. i is revolubly mounteii' upon! a-. central: shaft. i1: having-1. two. outer ter minal; trunnion-like.- portions to. and M1,. whereby; the shaft. is no'n-revoluhly mounted; in: any suitable. stationary. housingi may bee formed: of front and rem sepambie half-sections 5b: and 6a) The; huh 1* may: be formed. oftwo: hollow chamber-forming. portions:= 1-2. and lit 1'8? spectively. Chamber-portion I :2: houses electrical? collector. rings and brushes- (not shown) similar to those disclosed; in my Patent; 2:,39h8fll lion maintaining electrical; connection. between the inner end. of. the: cord 8. and the fixed eleotrioazll cord 8a: which leads to; any suitable eleotriicsl: motor: or the; like; being" supplied with. electric; current by the reel assembly;

The hub-portion |3 houses a flat spiral takeup spring |3a Which is anchored at its inner end to the stationary shaft 9 and is operatively connected, at its outer end to the interior of the hub-portion I3.

The hub-portion 2 may be provided with a thin flat integrally-formed flange [4 adjacent its outer edge while the hub portion l3 may be provided with a similar flange I5.

On one side of the reel, as for instance on the outer side of the flange IS, a shallow-dished sheet-metal housing It is provided; the housing I I5 being affixed, by any suitable fastening means, to the flange l5.

Within the housing 56, there is provided a ratchet-disc l9 having formed thereon one or more peripheral notches, as for instance, notches 20a and 29b, and corresponding dwells Ma and 2 lb. The ratchet disc is keyed to the non-circular end 22 of the shaft 9 so that it is held in nonrevoluble relationship to said shaft.

Apawl 25 is pivotally mounted, as at 25, upon the outer side of the flange I5; the pawl 25 being disposed in generally the same plane as the ratchet-disc l9 and being-provided with a heel 21 extending generally on the opposite side of the pivot 26. A generally triangular cam 28 is pivotly mounted, as at 29, upon the flange |5 in operative juxtaposition to the heel 21.

The pawl 25 is tensioned by a spring 3| so that it will be constantly urged in the direction of the ratchet-disc IS; the other end of the spring 3| being anchored to the flange l5 by a member 32.

The triangular cam 28 is provided with a pawlretracting shoulder 36 which is in operative juxtaposition to the heel 21 of the pawl 25. The cam 28 is tensioned by a spring 31 which is connected atone end to the ear 35 of said cam and, at its other end, to an anchorage member 38 formed on the flange |5.

The anchorage member 38 is so disposed in relation to the pivot 29 of the cam 28 that the spring 31 will, at all times, urge the camming shoulder 34 of the cam 28 against the ratchetdisc l9. That is, when the pawl 25 and the cam 28 are in the locked" position shown in Figure 4, the spring 31 urges the cam 28 counterclockwise to maintain the cam shoulder 34 in contact with the ratchet-disc l9. When the pawl 25 and the cam 28 are in the unlocked position shown in Figure 5, the spring 31 urges the cam 28 clockwise to maintain the camming shoulder 34 in contact with the ratchet-disc I9.

As more fully described in my Patent 2,391,840, the locking and unlocking operation of the reel is as follows:

- If the cord 8 is pulled out manually a short distance, in Figure 4, the hub 1 and the flange I5 are rotated clockwise in Figure 4. This rotational movement of the flange |5 (as well as of the pawl 25 and the cam 28 which are mounted upon the flange) first causes the pawl 25to be kicked out of the notch 20a because of the gradual inclination of the'surface 4 l' which is at an acute angle to the radius from the pivot 25 of the pawl 25 (whereas the opposite pawl surface 42 is approximately'at a right angle to this radius) thereby lifting the pawl onto the dwell 2|a, and, as the pawl 25 further recedes from the notch 20a, the camming shoulder 34 of the cam 28 moves toward, and finally drops into, notch 20b in something less than a half revolution after the pawl 25 has been kicked out of the notch 28a. This intermediate position of the pawl 25 and cam 28 is shown in dash-dot lines in Figure 4.

If the operator then releases cord 8, the spring I30, rotates the hub and the flange |5 counterclockwise in Figure 4 to wind-up the extended or payed-out portion of the cord 8.

During the first portion of this counterclockwise rotation of the flange I5, the camming shoulder 34 of the cam 28 will be rotated counterclockwise so as to bring the pawl-retracting shoulder 36 against the heel 2'l of the pawl 25 as indicated in Figure 5, so as to retain the pawl 25 in the unlocked position so long as the hub and the flange |5 are rotating counterclockwise to wind-up the payed-out portion of the cord 8; there being a series of audible clicks during this re-winding operation, each click resulting from the momentary entry of the camming shoulder 34 of the cam 28 into one of the notches 20a and 2822.

When it is desired to stop the re-winding of the cord 8 and to lock the reel with the cord in a partially re-wound position, the operator manually grasps the payed-out portion of the cord 8 so as frictionally to bring it to a halt. He then pulls'the cord outward a slight distance which results in clockwise rotation of the flange l5 from the position shown in Figure 5 until the camming shoulder 34 of the cam 28 enters the notch 20b as evidenced by a click. If the cord. were simply released at the sound of this first click flange |5 would move back to the position shown in Figure 5 and the reel would continue to rewind as described above.

If, however, the cord is pulled out a little bit beyond the point at which the first click" is heard, there will be a second click evidencing the dropping of the pawl 25 upon the dwell 2|a under the action of the spring 3| (the pawlretracting shoulder having been moved to nonengaging position relative to the heel 21 during this additional rotation).

If the cord 8 is then released the flange l5 rotates counterclockwise in Figure 4 until the pawl 25 engages within notch 20a as shown in solid lines in Figure 4 so as to lock the reel against further rewind.

From the foregoing, it is evident that the reel can be manually adjusted to unwind, lock, release, and re-wind as desired, in generally the same way as described in myPatent 2,391,840.

The novel braking mechanism of the present invention will now be described as applied to the above-described reel-mechanism.

A brake-drum 49 is fixedly mounted upon the shaft 9 adjacent the inner side of the housing half-section 6a. A brake-lining '58 is fitted about the rim 5| of the drum 49. A pair of locking ears 52 may be struck inwardly from the rim 5|; the ears 52 being so positioned as frictionally to retain the free ends 53 of the one piece brake-lining 58 when said ends are inserted within the opening in the rim 5| formed intermediate the ears 52, as shown particularly in Figures 4 and 5. In this way, the brake lining in (which may be of any suitable rubber, asbestos and/or cork composition such as is well known in the braking art) is maintained snugly upon the rim 5|.

If desired, a slight outwardly-extending annular flange 54 may be provided upon the free edge of the rim 5| to prevent the lining 58 from ammo 5; pins 51 and 58. being arranged in diametricallyopposed positions on said; flange t5 and beins somewhat radially outward oi the brake drum 49. The levers 55 and 55- extend generally clockwise, in Figures 4 and 5, from their respective pivot pins 51 and '58.

A brake-band 55 is in the form ofa thin, flat band of spring-steel or other suitable resilient. material, has its ends 50 and 8-! twisted toa plane generally at right angles. to the plane oi the main body of the band; the ends 5.! and it being provided with slots 52 and 63 The slot .52 oi'the end 60. is adapted to be fitted over the enlarged head of pivot 51 of the lever '55 and to be retained thereon, as shownparticularly in Figures 3, 4, and 5.

The slot 63 on: the end H of the band 59 is adapted to be fitted over the enlarged head or a pin 56- carried by the lever 56 at a point appreciably spaced apart from the pivot-pin 58 of said lever 55.

The brake-band 59 is shaped so that it is more or less form-retaining and the relationship of the pivot pin 51 and the pin 64- is such that, when the band 59 is connected therebetween, a slightelearance is normally maintained between the brake-band 59 and the brake-lining 50 as indisatedin Figure 4.

In this position, the tension of the brake-band offers slight resistance tothe counterclockwise rotation of the lever 55.

As will be more fully described hereinbelow, it iii-desirable for best braking results that this tension be neither too great 'nor too-small. I

A similar brake-band M having twisted ends 65 and 66 provided with slots 61 and 68 respectively isconnected intermediate the pivot pin 58 and a pin 55 carried by the lever 55-; the slot 51 fitting over and being retained upon the pin 58 and the slot 68 fitting over and being retained uponthe pin 59'. Weights l and I I may be provided at the free ends of the levers 55 and 55 respectivelyso as to increase the centrifugal force generated by the. levers during rotation of the huh I- and flange l; although said weights 1 5 and it may be dispensed with'where the effective moment of the lever masses is sufficient to provicle adequate centrifugal force.

' The operation of the novelbraking mechanism ofthe present invention is as'follows:

' When the hub I and the flange l5 are stationarygthe positions'of the lovers 55 and56 are general-Iy as shown in Figure 4 wherein there is no frictional restraintupon the brake-lining and wherein there is slight tensional resistance to 5 counterclockwise rotation of the levers and.

When the payed-out cord is released however, so that the hub 'l' and'fl'ange I5 start rotati'n-g counterclockwise in Figure 4, centrifugal force acting upon the levers 55 and 55 tends to rotate them counterclockwise about their respective pivot pins 51 and 5-8, against the relatively slight tension of the resilient brake-bands 59 and H, soas to move the pins '69 and 64 outward from their original positions shown in Figure i to the positions shown in Figure 5.

This results in tightening of the brake-bands 58 and M against the brake-lining 50 so as frictionally to slow the rotation of the hub F and the flange 15 relative to the stationary drum 49-.

It is desirable that the end pins holding the resilient brake-bands 59 and T4 be carefully positioned in order to obtain best braking results.

Thus, it the end pins are so positioned that the resilient brake-bands exert excessive restraining wind" speeds.

forceupon the levers 55 and 55, there wlll'be:h1- some-lent braking action sincebraking occur only when the speed of rewind becomes so great that the centrifugal force generated upon the levers 55 and 55 adequate to overcome the excessive restraining some of the resilient brake-bands 58' and 14.

If, on the other hand, the end pins of the resilient brake-bands '55 and T4 are so positioned that insufiicient restraining force is exerted upon the levers 55 and 58, there will be excessive braking action since the levers will tend to fly readily upon even slow rotation of the reel. a result,. the reel would rewind at extremely stow speeds and, indeed, rewinding might be. brought completely to ahalt.

In general, it desirable that the. resilienceot the brake-bands 5k and H beadjusted so as just to compensate for the spring-drag during winding; thereby to ensure smooth row-Indira at a desired rate-oi-speed and without excessive or insuflicient or jer "rewinclingaction.

In. general, it desirable to so adjust the resilient brake- bands 59 and 14 as togive a rewind speed of approximately five feet per second.

This prevents the electric cord from being rewound at excesssive speeds and eliminates the danger or whipping 01" other similar action which may cause injury to the operator.

It is also obvious that only a single lever and brake-band. could. be employed (in place of the pair shown in Figures 4 and 5) or that three or four or any other number of such lcvereand-band combinations could be .circumferentially disposed on the flange I5 about the brake-drum.

If desired, the brake-drum 49 can be weldedto the inner side of the housing half-section it: so that the brake-drum and the half-section can be assembled upon the trunnion l5 together, after which the entire assembly canbe locked together by the bolt H.

While, for the purposes of illustration, my novel braking mechanism has been described in con.- junction with the reel of my Patent 2,391,845, the present invention contemplates'the use of this braking mechanism with other types or reels.

The present invention further contemplates the use of my novel braking mechanism to provent excesssive pay-cu" speeds as well as re- That is, it is obvious that if the flange I 5 were rotated clockwise in Figure 5 can is-,-in the pay-out direction) at excessive-speeds, centrifugal force generated upon the'levers ti and l5-wou-1d again cause them to rotate counterclockwise so as to tighten the brake- bands 53 and 14 against the brake-lining 50 and thereby frictionally to restrain the rotation.

In addition to reducing the danger-of accidents due to lashing or whipping 0f the free I end of the cord during exccssivel'yrapid rte-winding, the novel braking mechanism of the present vention affords other important advantages.

Thus, if the braking mechanism of the present invention is not used, there will be a considerable strain placed upon the connections betweenthe As. a result, after many rewindings without braking mechanism these connections tend to be weakened and eventually to fail.

With the novel braking mechanism of the present invention, on the other hand, the speed of rotation durin re-winding is reduced to a point at which the electrical connections and the plug are. capable of withstanding stopping stress without appreciable tendency toward failure.

. Additionally, the novel braking mechanism of the present invention results in a more uniform distribution of the cord upon the reel during rewinding.. That is, when the speed of re-winding is excessive, the cord tends to wind itself about the reel too loosely so that the reel becomes filled and crowded before all the cord has been rewound. With'my. novel braking mechanism, on the other hand, the cordwinds itself upon the reel more tightly (due to the lower re-winding speed) and thereby tends to distribute itself more uniformly upon the reel. This not only makes it certain that the long cord will be accommodated upon the reel, but also give easier and smoother pay-out motion.

The present invention may be embodied in other specific forms Without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiments be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description'to' indicate the scope of the invention. Having thus described my invention, I claim as new and desire to protect by Letters Patent:

l; 1. In a reel having a housing and a cord-carryins member rotatably mounted within said housing; means for automatically braking said cordcarrying member when its speed of rotation becomes excessive, said means comprising a lbrake-drum fixedly mounted within said housing, a brake-lining of friction-creating material fitted upon said brake-drum, a lever pivotall mounted at one end upon said rotatable member and constructed and arranged to swing outward under the action of centrifugal force generated during .rotation of said rotatable member, and a curved somewhat form-retaining brake-band of resilient ribbon steel or the like connected at one end to said lever at a point appreciably spaced from the pivot thereof and fastened at its other end to said rotatable member at a point substantially circumferentially spaced from said lever, said brakeband being constructed and arranged normally to extend arcuately in slightly radially spaced relationship to said brake-lining and to exert inward tension upon said lever, said lever being constructed and arranged to swing outward against the tension of said brake-band when the speed of rotation of said cord-carrying member becomes excessive thereby to reduce the curvature of the brake-band and to bringit into contact with the brake-lining so as to reduce the speed of rotation of said cord-carrying member; the brake-band acting to retract the lever and to return to its normal radially spaced-apart relationship relative to said brake-lining when the speed of rotation of said cord-carrying member has been reduced.

2. In a reel having a housing and a cord-carrying member rotatably mounted within said hous ing; means for automatically braking said cordcarrying member when its speed of rotation becomes excessive, said means comprising a brakedrum fixedly mounted within said housing in axially-spaced relationship to said cord-carrying member, a brake-lining of friction-creatingmate rial fitted upon said brake-drum, a lever eccen-; trically pivoted to said rotatable member and constructed and arranged to swing outward under the action of centrifugal force generated during rotation of said cord-carrying member, said lever being, positioned in generally the same radial plane as the brake-drum but substantially radiall outward therefrom, and a curved somewhat form-. retaining brake-band of resilient ribbon steel 01fv the like connected at one end to said lever at a point appreciably spaced from the pivot thereof andfastened at its other end to said cord-carrying 'member at a point appreciably circumferentially spaced from said lever, said brake-band being constructed and arranged normally to extend arcuately in slightly radially spaced relationship to said brake-lining and to exert inward tension upon said lever, said lever being constructed and arranged to swing outward against tension of said brake-band when the speed of rotation of said cord-carrying member becomes excessive thereby to reduce the curvature of the brake-bandand to bring it into contact with the brake-lining so as to reduce the speed of rotation of said cord-carrying member; the brake-band acting to retract the lever and to return to its normal radially spaced-apart relationshi relative to said brake-lining when the speed of rotation of said cord-carrying member has been reduced.

3. In a reel having a housing, a cord-carrying member rotatably mounted within said housing, a helical spring operativel connected to said cord-carrying member and urging it for cordrewinding rotation, latching-mechanism operatively connected to said rotatable member whereby the said member can be adjusted at will to lock in any predetermined cord-extended position and to unlock for continuous spring-actuated cordrewinding rotation; means for automatically braking said rotatable member so as to prevent excessively rapid cord-rewinding rotation thereof, said braking means comprising an annular brakedrum fixedl mounted within said housing in axially spaced relationship to said cord-carrying member and having a brake-lining of frictionoreating material tightly fitted thereon, a-levcr pivotally mounted at one end upon said rotatable member and constructed and arranged to swing outward under the action of centrifugal force generated during rotation of said rotatable memher, and a curved somewhat form-retaining brake-band of resilient ribbon steel or the like connected at one end to said lever at a point appreciably spaced from the pivot thereof and fastened at its other end to said rotatable mem ber at a point substantiall circumferentially spaced from said lever, said brake-band being con structed and arranged normally to extend arcuately in slightly radially spaced relationship to said brake-lining and to exert inward tension upon said lever, said lever being constructed;;and arranged to swing outward against the tension of said brake-band when the speed of rotation of said cord-carrying member becomes excessive thereby to reduce the curvature of the brake-band and to bring it into contact with the brake-lining so as to reduce the speed of rotation of said cordcarrying member; th brake-band acting to retract the lever and to return to its normal radially spaced-apart relationship relative to said brake-lining when the speed of rotation of said cord-carrying member has been reduced.

4. In a reel having a housing, a cord-carrying member rotatably mounted within said housing, a helical spring operatively connected to said cord-carrying member and urging it for cordrewinding rotation, latching-mechanism operatively connected to said rotatable member whereby the said member can be adjusted at will to lock in any predetermined cord-extended position and. to unlock for continuous spring-actuated cord-rewinding rotation; means for automatically braking said rotatable member so as to prevent excessively rapid cord-rewinding rotation thereof, said braking means comprising an annular brake-drum fixedly mounted within said housing in axially spaced relationship to said cord-carrying member and having a brakelining of friction-creating material tightly fitted thereon, a lever eccentrically pivoted to said rotatable member and constructed and arranged to swing outward under the action of centrifugal force generated during rotation of said cordcarrying member, said lever being positioned in generally the same radial plane as the brakedrum but substantially radially outward therefrom, and a curved somewhat form-retaining 1:

brake-band of resilient ribbon steel or the like connected at one end to said lever at a point appreciably spaced from the pivot thereof and fastened at its other end to said cord-carrying member at a point appreciably circumferentially spaced from said lever, said brake-band being constructed and arranged normally to extend arcuately in slightly radially spaced relationship to said brake-lining and to exert inward tension upon said lever, said lever being constructed and arranged to swing outward against the tension of said brake-band when the speed of rotation of said cord-carrying member becomes excessive thereby to reduce the curvature of the brakeband and to bring it into contact with the brakelining so as to reduce the speed of rotation of said cord-carrying member; the brake-band acting to retract the lever and to return to its normal radially spaced-apart relationship relative to said brake-lining when the speed of rotation of said cord-carrying member has been reduced.

5. In a reel having a housing and a cordcarrying member rotatably mounted within said housing; means for automatically braking said cord-carrying member when its speed of rotation becomes excessive, said means comprising a brake-drum fixedly mounted within said housing, a brake-lining of friction-creating material fitted upon said brake-drum, a pair of pins mounted upon said cord-carrying member and extending axially therefrom at generally diametrically-opposed points relative to said brakedrum, a governor lever eccentrically pivoted upon each of said @1118, said levers being disposed in generally the same radial plane as said brakedrum and being constructed and arranged to swing out under the action of centrifugal force generated during rotation of said cord-carrying member, a generally curved somewhat formretaining brake-band of resilient ribbon steel or the like fastened at one end to each of said pins and connected at its other end to the opposite lever at a point somewhat spaced from the pivot thereof, said brake-bands being constructed and arranged normally to extend arcuately in slightly radially spaced relationship to said brake-lining and to exert inward tension upon said governor levers, said levers being constructed and arranged to swing out against the tension of said brake-bands when the speed of rotation of said cord-carrying member becomes excessive thereby to reduce the curvature of said brake-bands and to bring them into contact with the brakelining so as to reduce the speed of rotation of said cord-carrying member; the brake-bands acting to retract the governor levers and to return to their normal radially spaced relationship relative to said brake-lining when the speed of rotation of said cord-carrying member has been reduced.

ADOLPH MELETTI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 291,001 Powell Dec. 25, 1883 667,887 Mayer Feb. 12, 1901 715,691 Porter Dec. 9, 1902 1,658,561 Kennington Feb. 7, 1928 1,948,158 Barr Feb. 20, 1934 2,159,004 Bosch May 23, 1939 2,391,840 Meletti Dec. 25, 1945

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