US1173685A - Brake. - Google Patents

Description

0. F. SHEPARD, JR-

BRAKE.

APPLICATION FILED MAY 5, 1906.

Patented Feb. 29, 1916,

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OSCAR F. SHEPARD, 53., OF CINCINNATI, OHIO.

BRAKE.

Specification of Letters Patent.

Patented Feb. 29, 1916.

Application filed May 5, 1906. Serial No. 315,395,

To all whom it may concern:

Be it known that I, OscAR F. SHEPARD, J r., a citizen of the United States of America, and a resident of Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Brakes, of which the following is a specification.

This invention relates to certain improvements in brake-mechanism and its object is to provide a device of this character of a comparatively simple and inexpensive nature and of a compact and strong construction which shall be capable o-foperation in such manner that when the reciprocallymovable object has reached or approached the limit of its movement in one direction a braking action will be exerted upon the power apparatus to prevent further movement of the said movable object in that direction without in any way, however, retarding the operation of said power apparatus when actuated to reversely'move the said movable object.

Theinvention consists in certain novel features ofthe construction, and combinations and arrangements of the several parts of the improved brake-mechanism, whereby certain important advantages are attained and the device is rendered simpler,.cheaper and otherwise better adapted and more convenient for use; all as will be'hereinafte'r fully set forth.

The novel features of the invention will be carefully defined in the claims.-

In the accompanying drawings which serve to illustrate the invention: Figure 1 i a fragmentary view showing certain parts of an elevator mechanism provided withmy improvements, the brake-pulley being broken out and shown in section to illustrate the arrangement of the brake-levers housed therein; Fig. 2, a fragmentary elevation of the samev parts as viewed from the right-hand side of Fig. 1; Fig. 3, an enlarged sectional view taken through the brake-pulley for illustration of the normal or neutral positions of the brake devices housed in said pulleys; and Fig. 4, a view similar to Fig. 3, but showing the brake devices. operated in one directionto stop the motion" of the brake-pulley.

In these views, I have shown my brakemechanism as applied to n elevator or hoisting machine, but it is to be understood that the said brake-mechanism may be applied equally well to a planer, railwaycar, or other like object that is movable 1n either direction. The following description,

however, will be confined in it details to.

the application of my improvements to an elevator or hoisting machine, or, more particularly, to that class of devices commonly known as limitation-stops which are employed in elevator construction for throwing the hoisting apparatus out of operation when the cage or car has reached the limit turn with the motor-shaft 2 and adaptedto receive braking-pressure whenth cage or car has reached its limits of movement in ascending or descending, whereby the movement of said shaft 2 and of the winding-drum 3 is retarded and damage prevented to the cage and also, to preventother mechanical parts of the elevator fro-m any jamming of the cage at the opposite ends of the well or shaft. v

8 indicates a frame erected adjacent to the side of the brake-pulley 7 and herein shown as of an inverted U-shape, being arranged with its arms at opposite sides of and to a curved connecting part or yoke above the shaft 2, and, upon said curved connectingpart or yoke of the frame 8 is a laterally-directed supporting-bracket 9., extended within the hollow of the brake-pulley 7, while upon the upright portions or arms of the frame, at opposite sides of shaft 2, are produced similar projections 10, 10, also extended within the hollow of the brake-pulley 7, at opposite sides of shaft 2 and forming stops or rests wherewith the brake-levers, housed within the hollow of said pulley 7, are adapted to alternately engage when. actuated to brake the movement of shaft 2 in opposite directions.

11, 11 represent the brake-levers arranged within the hollow of pulley 7 and curved toconform to the peripheral shell thereof, being pivotally connected as shown at 12 at their adjacent ends at a point vertically alined over the shaft 2 and being adapted to be supported at their upper connected ends by means of a pendent lug 13 on the lever 11 and which, in the normal, inactive or neutral position of the parts, shown in Fig. 3, rests at its lower end in a step or depression 9 made in the supporting-bracket 9 of the yoke or frame 8.

14, 14 are lugs or shoulders produced upon the levers 11, ll at points substantially alined at opposite sides of the shaft 2, and said shoulders are arranged to bear upon the projections 10, 10 on the arms of the frame 8, the proportions of the parts being such that when the levers stand in their retracted or inoperative positions, shown inFig. 3, with their pivotally-connected upper ends supported by the lug or projection 13 on the bracket 9, the lower pendent parts of said levers will readily swing toward each other until the respective lugs 14, and 14 engage the respective projections 10, and 10*, whereupon all parts of the brake-levers will be drawn inwardly out of all operative engagement'with the inner peripheral wall of pulley 7.

15 is an upper brake-shoe or block carried by the upper end of lever 11 above the pivotal-connection12, and 16, and 16 are similar brake-shoes or blocks carried by the respective levers 11, and 11 adjacent their'lugs 14, 14 and at opposite sides of shaft 2, and each of said brake-shoes 15,16 and 16 has a covering of leather or other suitable material for frictional contact upon the inner surface of the peripheral wall of pulley 7 said shoes being normally drawn in away from and out of contact with saidsurface as shown in Fig. 3 in the normal inactive or neutral position of the parts. It will be seen, in the upward movement of the levers.

11, 11 that the block 15 acts in the capacity of a buffer primarily and, secondly, as an auxiliary brake-shoe in connection with the brake-shoes proper 16 and 16.

The lower ends 17 17 of levers 11, 11 below the brake-shoes 16, 16 are laterallybent in a horizontal direction toward each other and beneath shaft 2 and are provided with vertical shoulders or bearing-surfaces facing each other but spaced apart to receive between them an eccentric 18 in the form of a flattened block or piece of metal the opposite flattened faces of which are arranged to bear upon the shoulders or bearing-surfaces of the said horizontallydirected lower ends 17 17 of the brakelevers, the longer axis of said eccentric block 18 being normally in a vertical plane as shown in Fig. 3, so that the shoulders of levers 11, 11 are permitted to approach each other sufliciently so that the brake-shoes may be withdrawn from contact with the pulley 7 in the neutral or inactive position of the parts. The extremity of lever 11 has a lateral extension or guide-finger 20' extended from the base of its bearing-surface or shoulder beneath eccentric 18 to serve as a support for said eccentric 18.

The eccentric 18 is carried on a rock-shaft or lever 19, having a pendent arm with which is connected one end. of a link 21, the opposite end whereof has connection with a pendent arm 22 on a horizontal shaft 23, extended parallel with the shaft 2 across the lower part of drum 3, there being an arm 24 at the opposite end of shaft 23 and connected with a vertically-extended slide-rod 25, the lower-end of which latter has a nut or collar 26 below which is arranged a spring 27, the tension of which is normally exerted in such a way as to uplift said sliderod 25 and maintain the parts in the positions shown in Figs. 1, 2 and 3 with the eccentric 18 in vertical position between the shoulders of levers 11 and 11.

The slide-rod 25 has a forked upper end 28 that engages a guide-shaft 29 which may form part of the hoisting apparatus and has thereon the collars 30, 30, between which latter the said forked part 28 of the sliderod is arranged and guided for vertical movement. At opposite sides of said forked end 28 of the slide-rod are corresponding projections 31 (only one of which is herein shown), arranged, in the normal uplifted position of the slide-rod, to stand in the path of stop nuts or collars 32 and 32 adjustably held on the outwardly-projecting end of a horizontal screw-threaded shaft 33, which latter has engagement with arms or bearings 34, 34 spaced apart upon the frame 5 above the winding-drum shaft 4.

35 is a worm-wheel feathered or splined to a horizontal shaft 33, the latter having a threaded or screw formation at one end v thereof whereby it is adapted to reciprocate in opposite directions in its threaded bearin'gs that form part of the bracket-arms 34 and while rotating in unison with said worm-wheel, and 36 is a worm held on the projecting end of shaft 4 of the windingdrum 3 and in mesh with said worm-wheel, in such a way that rotatory movement is imparted to said worm-wheel in unison with the movement of the winding-drum and in one or the other direction according as the drum is rotated to raise or lower, the cage or car and by reason of the engagement of the threads of'shaft 33 within the arms v34, 34, it is evident that such movement will set nuts or collars 32, 32 and the stop nuts or-collars have projections or cams which, when the shaft 33 is moved endwise in one or the other direction, are adapted, as the said set-collars come opposite the projections 31, to. engage thereon in such a way as to impart endwise movement to slide-rod 25. The length of the projecting threadedend of the shaft 33 is such that the collars or nuts 32, 32 are permitted to beadjustably secured on the shaft-in positions at opposite sides of slide-rod 25, and by this arrangement it will be evident that as the drum 3 turns in one direction, imparting its movement to turn the shaft 33 in one direction and at the same time to move the shaft 33 endwise in one direction, the cam of one of said nuts or collars 32 or 32 will be caused to bear down on the projection 31 at one side of the upper end 28 of sliderod 25, whereby said slide-rod will be depressed, and as drum 3 turhs in a reverse direction, imparting reverse rotative and endwise movement to shaft 33, the cam of the other nut or collar 32 or 32 will be caused to bear upward from beneath the opposite projection 31 onsaid upper end of the slide-rod whereby said slide-rod will be elevated from the normal central position shown in Figs. 1 and 2. In this way, it will be seen that as the limit of movement of the cage or car in each direction is reached, the slide-rod 25 is either elevated or depressed, and by reason of the connection of said slide-rod with arm 24 it is evident that its movement will be imparted to reversely rock the shaft 23 as the car or cage reaches the limit of its ascending or descending movement, and when said shaft 23 is thus rocked in one direction as shown in Fig. 4, its connection with eccentric 18 serves to swing said eccentric to an inclined position between the parallel vertical shoulders or bearing surfaces of the levers 11, 11 whereby a Wedge-action is exerted to force the lower ends of levers 11, 11 apart from each other and bringing the opposite lateral brake-shoes 16, 16 thereon into frictional contact with the peripheral walls of the pulley 7.

Presuming the direction of movement of pulley 7 to be indicated by the arrow :0 at

ley 7, the levers 11, 11

the operation of the levers, as above described, it is evident that, by reason of the supporting-engagement of lug 13 on bracket 9, the lower end of levers 11, 11 when forced apart will swing upward so as to release their lugs 14, 14 from the stops or rests 10, 10 and when this shall have been accomplished the brake-shoes 16, 16 being pressed into frictional-contact with thewall of pulwill be free to partake to a limited extent .of the rotatory movement of pulley 7 inthe direction of said-arrow 02 whereby said levers will be with the pulley 7. In case the pulley 7 be moving in a direction reverse to that indicated by arrow w, it is evident that, the cage or car being in movement also in a reverse direction to that above described, the apparatus will be actuated to impart reverse movement to the slide-rod '25, wheeby the shaft 23 and eccentric 18 will be rocked to positions reverse to those shown in Fig. 4, whereby a reverse movement of the levers 11, 11 will occur. By this arrangement it will be evident that the initial pressure on the brake-shoes is just sufiicient to cause them to adhere to the pulley and be carried to their operative positions and the brakingpressure at the start is slight. As the brakeshoes are further carried in the pulley they move in a direction to increase the angle of the eccentric 18 in relation to the bearing- =surfaces 17 and 17 and the brake-shoes are forced more strongly apart and the braking effect correspondingly increased. Should the car continue to move, the shaft 33 will be rotated still farther and the slide-rod 25 will be further moved by the set-nut, and hence the eccentric 18 will cause gradually increased pressure onthe brake-shoes. Thus the braking force is applied in a gradual and regulated manner and there is no-liability of damage to the parts or injury to the cage. When the apparatus has been actuated in this way to stop the movement of shaft 2, it will be evident that since one of the levers (lever 11 as shown in Fig. 4) will have been moved in unison with pulley 7 in such a way as to materially lift its lug 14? off the corresponding stop or rest 10 of the frame 8, and when the parts stand thus, no braking eflect will be exerted in case of reversal of movement of the shaft 2, such reversal of movement acting, by reason of the friction exerted .by pulley 7 on the brakeshoes, to reversely-move the levers from the position shown in Fig. 3, but since, in such reversed position of the levers their bearing surfaces or shoulders-are thrown substantially in line with the inclined sides of the eccentric 18, the Wedge-action of said eccentric will cease and said levers 11, and 11 will be permitted to swing toward each other sufliciently to withdraw their shoes 15, 16 and 16 from frictional-contact with pulley 7. Thus, what may be practically termed a floating set of brake-shoes is provided for 'scending movement of the cage or car. This is a material advantage in apparatus of this kind since it obviates loss of power at the commencement of reverse movement when the cage has been stopped or reached the limit of its movement in either direction, the brake device constructed according to my invention serving to effectively stop the movement of the apparatus in one direction but ofl'ering no resistance whatever to free movement of the apparatus in a reverse direction after stoppage. It will also be observed in the operation of my device that, should the drum not stop at once when the brake is initially applied, any further movement of the drum would cause the brakelevers to be pulled tighter and tighter until the brake-pulley is forced to stop and with it the drum.

'From the above description of my improvements, it will be obvious that the improved brake constructed according to my,

invention is of an extremely simple and inexpensive nature and is especially well adapted for use by reason of the fact that it permits of certain and accurate limitation of the movement of the elevator car or cage, or of any other reciprocally-moving device to Which the brake is applied without ofi'ering unnecessary resistance to the reverse movement When such limit of movement has been reached and Without necessitating any special releasing operation such as is required for ordinary braking appliances for the release of the retarding appliances (Where such retarding appliances are used, of course,) before such reverse movement can be effected. It will also be obvious from the above description that the device is susceptible of considerable modification without material departure from the principles and spirit'of the invention and for this rea son I do not desire to be understood as limiting myself to the precise form and arrangement of the device herein set forth in carrying out my invention in practice; For instance, (and Without necessity of showing it herein,) an external floating band or one or more floating brake-shoes, the latter similar to those above described, could be used in connection with the outer face of the pulley 7 or other, rotatory part, instead of using the brake-shoes internally of the pulley or rotatory part.

I claim 1. A brake mechanism comprising adriven part, a plurality of pivotally-jointed brake members whose outer surfaces are adapted for braking contact within said driven part, an additional brake shoe mounted on one of the brake members adjacent to the pivotal connection of the brake members and, also, adapted for braking contact within said driven part, a rock bar or eccentric lying intermediate the lower free ends of said pivotally-jointed brake members and adapted to move said brake members into and out of contact with the said driven part, lugs on said brake members, and a stop device comprising an inverted U-shape frame having lugs disposed in the path of said lugs on the pivotally-jointed brake members, one of said brake members being adapted, when moved. into contact with said driven part, to be moved in unison therewith and into or out of engagement with said stop device to suit the direction of movement of said driven part. I

2. A brake-mechanism comprising a driven-part, a brake-member having a surface adapted for inner peripheral rim braking-contact' with said driven-part, and actuating means for moving said brake-member into and out of said inner peripheral rim contact with the driven-part and'comprising a movable or pivotal member contacting with and adapted to exert a radially spreading or wedging action on said brake= member to outwardly force the latter into said inner peripheral'rimcontact with the driven-part, said brake-member being adapted, when moved into said inner peripheral rim contact with the driven-part for movement in unison therewith to increase or 'diminish the said spreading or Wedging action exerted by said movable or pivotal member of the actuating means according to the direction of reciprocal movement of the driven-part. I

3. A brake-mechanism comprising a driven-part, abrake-member having a surface adapted for inner peripheral rim braking-contact with said driven-part, actuating means for moving said brake-member into and out of said inner peripheral rim contact with the driven-part and comprising a movable or pivotal member contacting with and adapted to exert a radially spreading or wedging action on said brake-member to outwardly force the latter into said inner peripheral rim contact with the driven-part, said brake-member being adapted, when moved into said inner peripheral rim contact with the driven-part for movement-in unison therewith to increase or diminish the said spreading or wedging action exerted by said movable or pivotal member of the actuating means according to the direction of reciprocal movement of the driven-part, and means to limit the reciprocal movement of the brake-member in unison with said moving-part. 4. The improved brake-mechanism comprising a rotating shell, stops or rests at opposite sides of the axis of rotation thereof, connected brake-members adapted for independent movement on said stops or rests into and out of contact with the shell, Whereby, when one member is operatively engaged with its stop or rest and with said shell, the other member is drawn away from its stop or rest, and means to operate said members.

5. A brake mechanism comprising a driven part, a plurality of brake members havingv surfaces adapted for braking contact upon said driven part, and actuating means for moving said brake members into and out of contact with the driven part, and

comprising a movable member contacting with and adapted to exert a wedging action on each brake member to force the same into contact with the driven part, each brake member being. adapted, when moved into contact with the driven part, for movement in unison therewith to increase or diminish the wedging action exerted by the movable member of the actuating means, according to the direction of movement of the driven part.

, 6. A brake mechanism comprising a driven part, a plurality of brake members having jointed connection and provided with surfaces adapted for braking contact upon said driven part, and actuating means for moving said brake members into and out of contact with the driven part, and comprising a movable member contacting with and adapted to exert a wedging action on each brake member to force the same into contact with the driven part, each brake member being adapted, when moved into contact with the driven part, for movement in unison therewlth to increase or d1m1n1sh the wedging action exerted by the movable member of the actuating means, according to thedirection of movement of the driven part.

7. A brake mechanism comprising a driven part, a plurality of brake members having surfaces adapted for braking contact upon said driven part, actuatingmeans for moving said brake members into and out of contact with the driven part, and comprising a movable member contacting with and adapted to exert a wedging action on each 'brake member to force the same into contact with the driven part, and a stop device adapted to limit the movement of said brake members, each brake member being adapted, when moved intocontact with the driven part, for movement in unison therewith to increase or diminish the wedging action exerted by the movable member of the actuating means, according to the direction of movement of the driven part.-

8. A brake mechanism comprising a driven part, a plurality of brake members having jointed connection, and having, at points remote from such jointed connection, surfaces adapted for braking contact upon said driven part, a brake shoe connected with the brake membersadjacent to their jointed connection and also adapted for braking contactupon said driven part, and actuating means for moving said brake members into and out of contact with the driven part, and comprising a movable member contacting with and adapted to exert a wedging action on each brake member to force the same into contact with the driven part, each brake member being adapted, when moved into contact with the driven part, for movement inv unison therewith to increase or diminish the wedging action exerted by the movable member of the actuating means, according to the direction of movement of the driven part and to force said brake shoe into braking contact with said driven part. 9. A brake-mechanism comprising a driven-part, a brake-member having a surface adapted for braking-contact with said driven-part, actuating means. for moving said brake-member into and out of contact with the driven-part, and comprising a movable or pivotal member contacting with and adapted to bring said brake-member into contact with the driven-part, said brakemember being adapted, when moved into contact with the driven-part for movement in unison therewith to increase or diminish the contact-pressure exerted by said movable or pivotal member of the actuating means according to the direction of reciprocal movement of the driven-part, and means to. limit the reciprocal movement of the brake-member in unison with said moving-part.

Signed at Cincinnati, Ohio, this 10th day

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