US2267037A

US2267037A - Hand brake mechanism

Info

Publication number: US2267037A
Application number: US390377A
Authority: US
Inventors: Everard C Mersereau
Original assignee: NAT BRAKE Co Inc
Current assignee: NAT BRAKE Co Inc; NATIONAL BRAKE COMPANY Inc
Priority date: 1939-03-30
Filing date: 1941-04-25
Publication date: 1941-12-23
Anticipated expiration: 1958-12-23
Also published as: US2282736A

Description

1941. E. c. MERSEREAU HAND BRAKE MECHANISM Original Filed March 30, 1939 Z6 67' 8 INVENTOR laws 7% ATTORNEYS Patented Dec. 23, 1941 i i j UWNITED STATE s. PATENT OFF ICE mm) 11mm- Mechanism O. Merlereau, Great Kills, N. Y., unmi to National Brake Company, Inc., New York. N. Y., a corporation of New York Origins 1941, Serial No. 390,311

1 Claims, (01. vi-sos) This invention relates to a hand brake mechanismfor railway cars which embodies a nonreturn detent device whereby the brake mechanism is held in its applied position, and also cam means whereby the brake mechanism may be gradually released without P r itting the hand wheel to spin backwardly,but which will cause the'backward pulling load of the brake mechanism to automatically relock the same against further releasing movement the instant that backward rotation of "the hand operated wheel ceases.

A hand brake mechanism of this character is shown and described in United States patent application No. 265,011 of which the present application is a division.

The'object of this invention is to provide an improved organization of this ype of brake 1 application March 80, 1939, Serial No. Divided and this application April 25,

outer side of the car wall 20, and comprises transverse front and rear walls 2|, 22, two longitudinal side walls 23, and a top 24 connecting the side walls, leaving the lower end of this casing open, as shown at 25. This casing may be secured to the wall of the car body in any suitable manner but preferably by means of a plurality of bolts 26 extending lengthwise through a the front and rear walls 2|, 22 of the casing and also through the wall of the car body, as shown in Fig. 2, each of said attaching bolts being surrounded within the casing by'a spacing sleeve or bushing 21.

Although the casing is represented in the drawing as mounted on the outer side of the car 1 body the brake controlling and operating mechanism contained therein is not dependent on such location of the casing inasmuch as the latter may be mounted within the car body without altering the brake controlling mechanism. For

convenience of description, therefore, the wall 2| of the casing will be regarded as the front side of the apparatus and the wall 22 as the rear side 'of the same.

Within the lower front part of the casing is arranged a chain drum or wheel 28 over which a flexible draft member 29 forming part of the 5 is a perspective view of a collar which 1 is mounted on the main operating shaft of the brake mechanism and provided with helical surfaces for cooperation with a gear pinion of-the clutch device forming part of the brake mechai Fig. 6 is an elevation of the brake mechanism,

on a reduced scale, viewed from the outer side of the same.

In the following description similar reference characters indicate like parts in the several flguresof the drawing.

Although the hand brake mechanism which embodies the present improvements may be variously organized as to details'of construction and the manner of mounting the same on a railway car the present construction is mounted on the upright end wall 20 of a car body and the same is capable of being operated from the exterior and also the interior of the car. 7

The main parts of this .brake mechanism are enclosed within a metal casing which also serves as the'main frame for this mechanism and, as

showninFiaLthiscasingisarrangedonthe brake mechanism is adapted to pass and interengagetherewith in a vmanner resembling a sprocket chain and wheel. consists preferably of a chain which has one end passing over the upper part of the chain drum or wheel. while the opposite end of the same is operatively connected with the brake shoes of the car. The chain is positively moved forwardly or backwardly upon turning the drum in the corresponding directions and thus cause the chain to be either tightened and the brake shoes pressed against the wheels of the car or loosened for releasing the pressure of the shoes against said wheels.

This drum is mounted for rotation on a longitudinal-axle or arbor 32 which is supported at its front and rear ends on

bearing disks

33, 34 secured, respectively, to the front and rear walls of the casing. Within the lower rear part of the casing is arranged a gear wheel 25 which turns with the chain drum 28 and is preferably cast in one piece therewith, as shown in Fig. 1. Above the chain drum and gear wheel 35 is arranged a main operating shaft which, in the construction shown in Fig. 1, is made in one piece and .has a front part I! of comparatively large diameter which i iournaied in a bearing I on the iront wall 2| of the casing and a reduced rear This flexible member part 89 which has a cylindrical collar 18 secured thereto by a transverse screw 11 and turning in a bearing 12 on the rear wall 22 of the casing.

On the front end of the main operating shaft 51, 89 is mounted a handle or manually operable wheel 48 which is arranged in front of the casing and outer side of the car body. Adjacent to the inner side of the front wall 21 of the casing the main operating shaft is provided with a front or abutment clutch disk 45 which is preferably formed integrally with this shaft. Opposing the Between the front or abutment clutch disk 45' and the rear or controlling clutch disk 48 is are ranged an intermediate or detent clutch disk 48 which is capable of forward rotation about the adjacent part of the main operating shaft. Detent ratchet means are provided whereby the detent clutch disk 48 is permitted to turn forwardly but is prevented from moving backwardly, which detent means preferably comprise an annular row of ratchet teeth 49 arranged on the periphery of the detent disk 48 and a detent pawl or dog 50 pivoted upon one of the casing fastening bolts 28 within the: casing and yieldingly held in engagement with the teeth 49 of the detent disk 48 by means of a spring 5| which is connected at one end with the detent pawl 50 while its opposite end is connected with an upper casing fastening bolt 28, as shown in Figs. 2 and 4, or with any other available stationary part of the casing. During the forward rotation of the detent disk 49'its ratchet teeth 49 tfip idly past the detent pawl 59 but backward rotation of this disk is prevented by engagement of this pawl with the tooth '49 of the detent disk immediately in front of this pawl, as shown in Fig. 4.

Clutch means are provided whereby a forward rotation of the main operating shaft in a clockwise direction, when viewed from the front of the casing, or in an anti-clockwise direction, when viewed from the rear of the casing, will cause the gear pinion 41 and its controlling disk 48 to be moved forwardly on the main operating shaft and cause the front abutment disk 45 to press against the front side of the detent disk 48 for compelling the latter to rotate forwardly with the main operating shaft, whichclutch means upon turning the main operating shaft backwardly will cause the rear controlling clutch disk 48 to be'movedaway from the rear side of the detent disk 48 and the front abutment disk 45 to release its grip on the front side of the abutment disk and thereby permit said front and

rear disks

45 and 48 to move backwardly independently of or in a clockwise direction, the hub l9 will be moved forwardly by a screw action and cause the controlling clutch disk to be pressed against the rear side of the detent disk 48 while the abutment disk 45 on the main shaft is pressed against the front side of this detent disk, thereby causing the latter to turn forwardly and trip idly with its teeth" past the detent ratchet mechanism which includes the detent dog or pawl 59 pivoted on one of the lower casing bolts 28 and held yieldingly in engagement with the ratchet teeth 49 on the detent disk 48 by the spring 51.

Upon turning the main operating shaft forwardly manually by means of the hand wheel 43 on one side of the casing, the cooperating helical faces 15 on the collar 10 of the operating shaft and the hub' 19 of the gear pinion 41 produces a wedging or cam action whereby the controlling disk 48 is moved axially forward relative to the main operating shaft and against the rear side of the detent disk 48 and also causes a rearward pressure of the abutment disk 45 against the front side of the detent disk 48, whereby the latter is gripped and caused to rotate forwardly with the operating shaft. While thus turning the main operating shaft forwardly, the gear pinion 4'? causes the main gear wheel 35 and the drum 28 connected therewith to also turn forward at a reduced speed or in the direction in which the brake chain 29 is moved forwardly or wound on the drum to take the slack out of the chain and cause it to move the brake shoes in the direction for pressing the same against the wheels of the car for braking purposes. Upon discontinuing the forward rotary movement of the main operating shaft, the same together with the chain drum are held in this position by engagement of the detent pawl 59 with the respective tooth it of the detent disk, whereby the brake mechanism is retained in its tightened condition and retards or stops the rotation of the wheels of the car. I

If it is desired to release the braking efiectof the shoes of the brake mechanism on the wheels of the car, the main operating shaft 81, 59 is the detent disk while the latter is being held against backward movement by the dog 59. Although various means may be employed for effecting this axial movement of the gear pinion 41 andcont'rolling disk 48 relative to the operating shaft this is accomplished in the construction turned backwardly to the desired extent, that is, in an anti-clockwise direction by operating the front hand wheel 49. When turning the main operating shaft backwardly the opposing helical faces 15, 14 on the collar 10 of the main operating shaft and the hub l9 of the gear pinion 41 cause the pressure of the rear or controlling clutch disk 48 against the rear side of the detentdisk 48 and the pressure of the front or abutment disk 45 against the front side of the detent disk 48 to be relieved, thereby releasing or unclutching the shaft 81, 89 and the gear pinion 41 and permitting the gear wheel 85, .and drum 29 to be turned backwardly by the load on the chain 29 which connects this drum with the brake shoe actuating mechanism. The instant, however, that the pressure of the rear and

front clutch disks

48 and 45 against the detent disk 48 i relieved by the backward movement of the gear pinion hub l9 during the backward rotation of the main operating shaft, the backward pull of the load on the brake chain 29 will turn the gear pinion 41 backwardly relative to the main operating shaft and in doing so, the cooperating helical or cam faces on the collar of the main operating shaft and the hub 19 of the gear pinion 41 will instantly cause this last mentioned disk to be moved axially forward against the rear side of the detent disk 4: and use press the abutment I disk 45 against the frontside of this detent disk and thereby produce a clutch action whereby further backward movement of the chain wheeler-i by-the operator to a greater or lesser extent in accordancewith the desired amount of release which itis desired to give the brake mechanism. this releasing effect on the brakes being arrested instantly when the operator ceases to turn the main operating shaft backwardly. It therefore fOllOWs that the operator by this means can release the brakes gradually and hold the brakes at any stage of the releasing operation asmay be necessary to meet requirements and also to immediately app y the brakes fully by again turning the main operating shaft forwardly the required extent. It will thus be evident that at no time can the main operating shaft spin or turn backwardly fully at a rapid rate so that the operator is not liable to be hit by any rapid backwardly rotating handle or hand wheel, nor is it possible for the brake mechanism to become released or unset fully at a rapid rate which otherwise would require taking up excessive slack in the brake rigging before the brakes are again fully set. Thi brake mechanism therefore is unengaged by the abutment disk 45 and collar 18,

respectively, but also enabling the brakeman to positively turn the gear pinion 41, gear wheel 35, and drum 28 backwardly in case these or other parts of the brake rigging should become stuck by rust or other cause, and thus aid in unwinding the brake chain and the parts connected therewith for effecting a release of the brake mechanism.

If upon turning the main operating shaft 61, 69 backwardly the gear pinion 41 is not turned backwardly due to insufficient load or pull on the draft chain 29 or due to the drum 28 and the gear wheel being stuck or any other reason, then the gear pinion 41 will move backwardly idly lengthwise of the main operating shaft until the rear end of the gear pinion 41 engages the collar 10 on the operating shaft 61, 69. When this occurs the gear pinion 41 becomes locked on the operating shaft and turns backwardly therewith as a unit, whereby a positive backwardly rotary movement is imparted to the gear wheel 35 and drum 28 by the manual power applied to the operating shaft 61, 69 and the draft chain is paid out from the drum. If therefore the gear pinion 41, the gear wheel 35, the drum 28 or any part of the brake rigging connecting this drum with the brake shoes should become stuck or operate sluggishly due to rust, dirt, snow, ice or other obstruction the resistance which otherwise might be imposed by said gear pinion and wheel and drum on the releasing movement of the brake rigg ng is eliminated and permits the remaining parts of the brake mechanism to relax and release the brake shoes from the car wheels.

Due to the cooperating cam faces which are formed respectively on the collar 10 of the main operating shaft and the hub of the gear pinion 41 the chain drum can be turned forwardly with :great'force for eflectively applying the brake mechanism by the sole use of manual power but since the backward rotation of the operating shaft by manual power is aided materially by the backward "pull of the load on the controlling disk it follows'that" the release of the brakemechanism can beeffected withmuch less power than that required for applying the same; This is particularly advantageous" in 'case a comparatively powerful brakeman has applied the brakes heavily and thereafter a brakeman" of less strength has to release the brakes.

For'the purpose of increasing the grip of the controllingdisk 43 against the side of the detent disk a friction disk 55 of suitable material is interposed between these members, and to permit prompt release of the abutment disk 45 from the detent disk a releasing disk 54 of suitable material is interposed between these last mentioned members, as shown in Fig-1.

When it is desired to manually operate the brake mechanism from only one side of the enclosing casing, for example, on the front side thereof, and on the exterior'of thecar as shown in Fig. 1, then only the main operating shaft 61, 69 is required to operate the brake mechanism.

Under normal conditions the controlling disk 46 is turned backwardly by the pull of the brake rigging immediately after manually effecting the first part of the backward turning movement of the operating shaft 51, 69 which is caused by the pressure of the controlling disk 45 and abutment disk 45 against the front and rear sides of the detent disk 48 being relieved due to the inclined or cam faces 15 of the collar 10 riding part way down the cooperating inclined or cam faces 14 on the hub 13 of the gear-pinion 41 and controlling disk 46, and thereby causing the brake mechanism to relax or release. When, however,

the grip of the controlling disk '46 against the detent disk 48 has beenreleased by the initial part of the backward movement of the operating shaft 61, 59 and said controlling disk is not also moved backwardly by the pull of the brake rigging on the same due to rusting or clogg ng of any of the parts, then the gear pinion 41 and controlling disk 48 will be positively turned backwardly by the manual power applied to the operating shaft 61, 68 at which time the shoulders l2 between the high and low parts of the cam surfaces 15 on the collar 10 engage with the shoulders II on the hub 13 between the high and low parts of the cam surfaces 14 thereof, whereby the gear wheel 35 and drum 28 are also turned backwardly and the brake chain 29 is unwound or moved backwardly from the drum and any resistance which this drum gear, wheel 35, gear pinion 41, and controlling disk 45 might offer-is eliminated and the brake mechanism is permitted to release itself.

In order to permit of operating the brake mechanism so that the winding drum will always turn in one direction while operating the same either from the interior or the exterior of the car and that during unwinding of the drum the same also turns in the opposite direction regardless of whether the same is controlled from the exterior of the car, auxiliary operating means are provided which are constructed as follows:

The numeral 11 represents an auxiliary operating shaft arranged above the main operating shaft and parallel thereto and having its front part extending across the upper part of the easing and journaled in bearings 18, 19 on the front and rear walls of the casing, while the rear part or this auxiliary shaft extends rearwardly through the adjacent wall 20 of the car body and is provided within the latter with an auxiliary handle or hand wheel OI. On the periphery of the abutment clutch disk 4' the same is provided with a gear rim or wheel II which meshes with a gear wheel I! turning with the auxiliary shaft I1 and preferably formed integr'ally with the front part thereof, as'shown in Fig. 1.

By means of this construction, the main operating shaft 81, 6! can be' turned forwardly by the brakeman grasping the front or main hand wheel 43 and turning the same clockwise while facing this wheel, and the main operating shaft can also be turned forwardly for setting the brakes by the brakeman turning the auxiliary hand wheel ll in a clockwise direction while facing the same inasmuch as the clockwisemovement of the rear or auxiliary hand wheel I due to the cooperating gear wheels I! and 83 which are mounted respectively on the main shaft 1, 6! and the auxiliary shaft 11. Release of the brake mechanism may also be effected by turning the front hand wheel 43 in an anti-clockwise direction while the brakeman faces this wheel and also by the brakeman turning the rear hand wheel 8| in an anti-clockwise direction while facing this last mentioned wheel. The ability of thus operating the brake mechanism from the rear of the casing or the interior of the car and also from the front of the casing or the exterior of the car by moving the internal and external hand wheels in corresponding directions when applying the brakes or releasing the same, confusion as to the proper direction for turning these hand wheels for setting or releasing the brakes is avoided. Moreover safety in the handling of the cars is increased inasmuch as no time is lost in promptly handling the brakes when this becomes necessary in case of an emergency.

Inasmuch as this mechanism permits of limiting the extent of release of the brake mechanism, it is possible to again fully set the brak without the necessity of taking up an undue amount of slack in-the brake rigging after the releasing operation before the brakes are again applied.

This hand brake mechanism is not only comparatively simple in construction but the same is also composed of relatively few parts which are not liable to get out of order and as a whole this brake mechanism is also very compact so that it is capable of being easily installed in places where a limited amount of space is available.

I claim as my invention:

A hand brake mechanism for operating the brake shoes of cars, comprising a chain adapted to be connected with saidbrake shoes, a drum over which said chain passes forwardly for tightening said brake shoes and backwardly for loosening said brake shoes, a gear wheel connected with said drum, a gear pinion meshing with said gear wheel, a controlling clutch disk connected with said gear pinion, an abutment clutch disk opposing said controlling disk, a detent disk in terposed between said controlling and abutment disks, a ratchet detent device which permits said detent disk to turn forwardly but prevents backward turning thereof, a manually operable main shaft connected with said controlling disk and having a main hand wheel arranged on one side of said disks, wedge means having cooperating helical faces which are arranged respectively on said shaft and gear pinion and which under the pull of a load on said chain constantly tend to press said abutment and controlling disks toward opposite sides of said detent disk and which upon turning said main shaft backwardly release'said abutment and controlling disks from said detent disk, a countershaft arranged parallel with said main shaft, intermeshing-auxiliary gear wheels turning respectively with said main and auxiliary shafts, and an auxiliary hand wheel arranged on :aigs auxiliary shaft on the opposite side of said EVERARD C. MIERSEREAU.