US1638380A - Shoe brake - Google Patents

Description

c. WASEIGE Aug. I 9, 1927.

SHOE BRAKE Filed Feb; 9. 1921 Patented Aug. 9, 1927.

UNITED- STATES PATENT OFFICE.

CHARLES WASEIGE, OF BILLANCOURT, FRANCE, ASSIGNOR TO SOCIETE DES AERO- PLANES HENRI & MAURICE FARMAN, OF BILLANCOUR'I, FRANCE, A CORPORATION OF FRANCE.

SHOE BRAKE.

Application filed February 9, 1921, Serial No. 443,556, and, in France February 19, 1920.

This invention relates to brakes of the kind'called shoe brakes; and one ob ect s to 7 ensure their energetic action in both directions of driving, whether forward or backthe brake control, which is secured to the wards, with a minimum of effort on the part of the driver.

Generally speaking,"the brake accordlng to the invention comprises a plurality of novel shoes of aluminium or the like faced with a netalloplastic band of asbestos and brass or other suitable material. These shoes are connected, as by a pivot, to each other, without a fixed anchor on the brake supporting plate or disc. At the end of each of the shoes opposite the joint or connection above referred to, may be mounted a steel plate provided with bosses engaging with the control cam and the ends of said plates are cut out to pivot about the spindle of the cam.

In the accompanying drawings by way of example,

Figure lshows an elevation of the brake according to the invention, in vertical section through the drum and just inside the wheel, to show the shoes in side elevation.

Figure 2' shows a vertical section through the vertical diameter of the brake.

Figures 3 and 4 are detail views of the joints. D

Figure 5 shows a constructional modification of the device shown in Figure 1, 1n which the cam of the brake is single instead of double. v I

Figure 6 is a detail View of the -jo1nt of the cam corresponding to the brake of Figure 5.

In the construction shown in Figures 1 and 2, the brake is constituted as'follows;

The bosses 5 and 13 of the two plates 5 and 13 secured to the shoes 1 and 3, are 1n permanent contact with the double cam 2 owingto the tension of the mam spring 6 which urges the two shoes toward each other. The latter are pivoted or otherwise connect-- ed at 12, but without a fixed anchor on the support or disc 4. The latter disc carries axle and does not rotate. The drum 7 is secured to the wheel. When the double cam is operated, the shoes are moved apart and brake the-- drum. The plates 5 and. 13 are cut out at the end so as to engage with and be guided by the spindle '15 of the cam.

If the cam 2 is operated whilst the wheel is rotating in the direction of the arrow, the

two shoes are spread out and, owing to their adhesion to the drum, they tend to rotatein the same direction. The thrust from shoe 1,"

the spindle 15, a great part of the thrust on the cam is transferred to the spindleso that the shoe 1 acts to a great extent as if it were actually pivoted on said spindle andthus the actuating force necessary to operate the cam is materially reduced. The shoes tend to open, and automatically increase the braking action (Fig. 1) exactly as in a brake with pivotally anchored shoes. Nevertheless, with the latter, the shoe is urged inwardly by the adhesion or friction of the drum when the wheels rotate in-the direction opposite to that of the arrow, and only the force applied to the control lever of the cam, ensures the braking. This disadvantage cannot exist in the brake construction with a double cam, the position of the shoes remaining the same in one direction as in the other. Preferably there are a pair of cams 2 on opposite sides of, and laterally guiding, the interfitting ends of the shoes (see Fig. 3), and engaging pairs of pins projecting laterally of the shoes.

The joint 12 being perfectly free, the brak ing action of each shoe is the same, since they balance each other, unlike in brakes with shoes anchored at a fixed point. In this latter case each of the shoes acts, in' fact, independently of the other.

As soon as. the braking is finished, the auxiliary spring 8 secured at one end to the shoe 1 at 10, and at'the other end to the disc 4 at 11, pulls the shoe back to the supporting face of afstop 9 adjustable from the outside of the drum by means-of a screw and nut. The adjustable stop 9 comprises a screw member secured at 1ts inner end to the shoe 1 and at its outer end extends. through a bracket on the fixed disc 4. On the screw member, outside of the bracket, is a nut for adjusting the length of said member inside of the bracket. By such adjustment the normal separation of the shoe 1 from the drum by the spring 8 can be regulated to provide more or less clearance between the two. The spring 8 normally pressing the shoes together on the cam, the spring 8 under tension connecting the shoe 1 with the tation of the earn as in cover disc and the adjustable stop 9 provide a resilient or floating suspension of theshoes within the drum, and by adjusting the stop 9 the relative positions of the shoes and drum can be regulated to meet the requirements. The slight looseness of stop 9 which is almost unavoidable in manufacture is sufficient to permit the slight lengthwise movements of shoe 1 as the brake is applied, whichever direction the drum may be turn- 1H0.

The spring 6, intending to pull back together the two shoes, producesa sudden disengagement of the same from the drum.

The auxiliary spring 8 not only cooperates with the stop 9 to determine the idle position of the shoes, but also insures engagement of shoe 8 with the drum prior to full engagement of the drum by shoe 1, the circumferential movement of shoe 3 caused by the friction of the drum serving to overcome spring 8 and force shoe 1 against the drum. When the vehicle is moving forward and'the drum is turning in the direction of the arrow, this 1 successive action of the shoes is especially same in the two directions.

The shoe 1 is in this case pivoted at one of its ends on the spindle 15 of the cam 14. It is coupled to the shoe 3 by a free joint 12 at its opposite end, as in the construction shown in Figure 1.

The shoe 3 carries a cut out plate 16, al-

ways held in engagement with the cam 14 by means of the return spring 6.

The working is as follows: v The wheel rotating in the direction of the arrow, if the cam 14 is operated, the joint of the two shoes land 3 being free, the shoes have the tendency to open out and to engage automaticallywith the drum, thus increasing the braking effort produced by therothe brake previously described. I

The thrust on the shoes being transmitted directly to the spindle of the cam, and 'not to the cam and spindle as in the case of the brake with a double cam, it follows that the said brake has the advantage of requiring a still smaller effort at the brake lever for producing as effective braking as in the preced.

ing case, but, as already stated, the braking cannot be exactly the same in both directions. i

From what has been stated, it follows that this brake makes it possible to obtain equal braking in the first case, or an almost equal braking in the second case, whether driving forward or reversing. The single friction device constituted bv two parts pivoted to each other, is expanded at the moment of braking on the whole inner surface of the drum, whilst in existing brakes of the said type, the braking depends on the fixing, during the machining, of theaxes of the joints, and it may happen that the shoes open in a manner non-ooncentric with the brake drum. In the case of a brake according to the invention, the contact surface is a maximum as in band brakes, the effort required for agood braking is therefore a small one.

Claims 1.. In combination with a drum and a fixed disc cover therefor, an internal brake for en gaglng the drum consisting of two articulated shoes, an operating spindle and cam disposed between the unconnected ends of said brake shoes and so arranged that the braking reaction is transmitted to the'spindle, a

spring connecting the two shoes and nor-,

mally tending to draw them toward the cam, and a second spring connecting one shoe with the disc cover and normally tending to separate this shoe from the drum, independently of the other brake shoe.

2. In a brake, the combination with an external drum and a fixed disc cover therefor, of a pair of brake shoes pivoted together at one of their ends and arranged within the drum and operative when opened to frictionally engage the inner periphery of said drum, a spindle mounted between the free ends of the brake shoes, a cam on the spindle between the free ends of the brake shoes to be rotated by the spindle to separate the shoes to effect frictional engagement between the shoes and the drum, a spring connecting the two shoes and normally tending toclose the same on the cam, a second spring 'connecting one of the shoes with the disc cover and normally tending to separate said shoe from the drum, and an adjustable stop to limit the separation of the shoe connected with the second spring from the drum.

3. In a brake, the combinationwith an external drum, of a pair of pivoted brake shoes arranged within said drum, a spindle mounted between the free ends ofthe brake shoes, said free ends being bifurcated to straddle said spindle, a cam mounted on said spindle each side of the'free ends of the shoes and cam engaging projections carried by said ends between which said cams are positioned, whereby, upon the turning of the cams, the free ends of the .shoes will be forced apart, causing the engagement of said shoes with the brake drum. I

4. In a brake, the combination with an external drum and a disc or cover therefor, .of

tween the opposite free'ends of the brake shoes, said free ends being bifurcated to straddle said spindle, oppositely disposed bosses or projections carried by said free ends, a cam mounted on the spindle between is turning in the other direction, a spring connecting the two shoes, a stop engaging one of the shoes, and a second spring urging said shoe against the stop.

. drum 6. In combination with a drum, an inter nal brake for engaging the drum consisting of a plurality of connected shoes having two separated ends, expanding means acting on said separated ends, the expanding means being arranged to take the braking torque from one shoe when the drum is turning in one direction and from the other shoe when' the drum is turning in the opposite direc tion, and a spring normally tending to hold said ends in engagement with the expanding means.

7. A brake comprising, in combination, a

drum, a plurality of, connected rigid shoes arranged within the drum to wrap with a self-energizing action against the drum in either direction of drum movement, and spreading means acting on the unconnected ends of the shoes and arranged to takethebraking torque from one of said ends when the drum is turningin one directionand from the other of said ends when the drum is turning in the opposite direction. 7

8. A brake. comprising, in combination, a drum, a plurality of connected rigid shoes arranged within the drum to-wrap with a self-energizing action against the drum in either direction of drum movement, and means between the unconnected ends ofthe shoes to serve as an anchor to take the braking torquein either direction of drum movement. i v

9. In combination with a drum, an internal brake therefor, having means for securing a self energizing elfect in both directions of rotation of the drum comprising a plurality of articulated brake shoes with means for taking the braking torque in either direction of drum rotation and means for insuring engagement of one shoe with the rior to full engagementtherewith of the adjacent shoe; v

10;In a brake mechanism, a rotatable member to be braked, a brake comprising at least two articulated shoes, an operating spindle, said brake shoes having separated ends, at least one being bifurcated and also engaging said spindle, said spindle acting a to assist in positioning said shoes, and means I for moving said shoes into contact with said rotatable member.

11. A brake comprising, in combination, a drum, a floating friction device extending approximately a full circumference within the drum and arranged towrap against the drum with a self-energizing action in either direction of drum rotation, a substantially cylindrical anchor memberextending between the free ends of said device and arranged to take the braking torque from either of said ends,'said ends being notched out to lit over the cylindrical anchor member, and expanding means acting on said ends.

having at least one free end, a cam for acting on said free end to move the brake into engagement with said rotatable member, a support for the cam, said free end being guidingly supported so as to hold it in proper working ,relation to said cam, said guide support including the end of the other shoe.. j

13. A brake comprising, in combination, a

drum, a pair of floating shoes within the, drum, means for taking braking torque from 1 one shoe when thedrum is turning in one direction and from the other shoe when the drum is turning in the other direction, ,and

a spring and a stOp cooperating to determine the idle position of one shoe, the idle position of the other shoe being determined at one end by the torque-taking means and at the other end by said one shoe.

14; A brake comprising, in combination,

a drum, a floating friction device extending approximately a full circumference within the drum and arranged to wrap against the drum with a self-energizing action in either direction of drum rotation, an anchor member projecting between the free ends of said device and arranged to take the braking torque from either of said ends, said ends being-notched out to fit over the anchor member, and expanding means, acting on said ends and carried by said anchor member.

15. In combination with a drum, an internal brake of the self energizing type wherein the rotation of the drum assists in applying the brake, said brake having two articulated shoes, an operating member arranged to apply said shoes to the drum, a returning springconneoted between said two shoes,

another spring having one end connected to one shoe near the articulated joint and the other end to a nonr'otating part of the wheel ingly urging the connected end of said adjacent shoe away from the drum while the first shoe is swung against the drum.

17. A brake including a drum and friction means within and engageable with the drum, said means comprising, in combination, a plurality of shoes arranged end to end and extending substantially more than 180, a connection between adjacent ends of the shoes, an operating device arranged to swing one of theshoes about the connection against a the drum, said. shoe moving circumferentially to force the adjacent shoe against the i drum, and a spring yieldingly urging the connected end of said adjacent shoe away from the drum while thefirst shoe is swung against the drum.

18. A brake comprising, in combination, a drum, connected shoes engageable with the drum, applying means, and a spring arranged adjacent the connected ends of the shoes and insuring that said shoes will be forced successively into fully effective" engagement with the drum.

19. A brake comprising, in combination, a drum, connected shoes engageable with the drum, applying means, and a spring arranged to insure thatsaid shoes will be forced successively into fully efiective engagement with the drum. I a 20. A brake comprising, in 'comblnation,

' a drum,-a plurality of connected shoes ar ranged end to end within thedrum, and 'a.

I cam acting on the free end of the end shoe,

the side of the cam engaging the side of the shoe for positioning said end laterally.

21. In a self-energizing brake comprising at least two articulated shoes, actuating means acting on at least one of .said shoes and yielding means for ensuring the engagement of oneshoe with a member to be braked previous to full engagement of another shoe.

22. A brake comprising, in combination, a

drum, a pair of. connected shoes within the drum, an adjustable stop engaging one shoe at least in idle position, and a spring urging said shoe toward the-stop and overcome in applying the brake by movement of the other shoe.

23. A brake comprising, in combination, a drum,- a plurality of shoes engageable with the drum and so arranged that at least in one direction of rotation of the drum one shoe forces the adjacent shoe against the drum, and means for taking the torque of said one shoe and said adjacent shoe at theend of said adjacent shoe toward which the drum is in that direction turning along the shoes and 25. A brake comprising, in combination, a

pair of shoes each having thrust parts, on its oppositesides, and a pair of double cams guidingly interengaging with the ends of the shoes and operatively engaging the four thrust parts. i

26. A brake comprising, in combination, a

pair of shoes having interfitting ends to guide each other, and means adjacent said ends for separating the shoes to apply the brake.

27. A brake comprising, in combination, a pair of shoes having a floating connection, a stop to determine the position of one of the shoes, a spring urging the shoe against the stop, a second spring engaging the other shoe and urging it toward an idle position, and means for applying the brake.

28. A brake including a shoe'having thrust parts on its opposite sides, in combinationwith an applying device engaging both of the thrust parts.

29-. A brake including, a shoehaving thrust parts on its opposite sides, in combination with two cams, each engaging one of the thrust parts.

A brake including a shoe having thrust parts on its opposite sides, in combination CHARLES WASEIGE,

Patent Nb. 1', 638,380.

CER IIFIGATE or CORRECTION.

I I Granted August 9,- 1927, to

1' CHARLES WASEI GE.

'It is hereby certified that the-above numberedpatent was erroneously issued to "Societe des Aeroplanes Henri & Maurice Farman, of Billaneourt; France, a corporation of France", whereas said Letters Patent should have been issued to "Bendix Corporatiom'oi Chic ago; Illinois, a corporation of Illinois", said corporation being assignee by mesne assignments of the entire interest, in said Letters Patent as shown by the records of'assignments in this office; and that the said Letters Patent should be read with this correction therein that the same mayfconform to the record of the case in the Patent Offioe.

Signed and sealed this 30th day of August, 'A. D. 1927.

t I I M. J; Moore, Seal. Acting Commissioner of Patents.

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