Sealed Non-spin Hand Brake Arrangement

Abstract

A hand brake of the non-spin type for railroad cars including a front casing and rear attachment plate that define a housing space for the brake operating shaft, ratchet wheel, ratchet wheel clutch, brake release mechanism, and drum gear, that is sealed from the elements by a seal applied between the two. The front casing is indented to define a mounting space for a single wind type brake drum, which is keyed to a mounting shaft that is journaled between the casing and a brake drum cover plate that may be secured to the casing in various positions relative thereto depending on the particular hand brake application desired. The drum extends into the housing space where it has fixed to same the drum gear and the drum carries a headed pin that anchors the brake chain to the drum, with the pin head cooperating with a stop block fixed to the casing to form a chain stop.

Description

My invention relates to a hand brake of the non-spin type for railroad cars, and more specifically to improvements in the hand brake shown in U.S. Pat. Nos. 2,416,251, 2,848,083, 3,390,590 and 3,444,756, and is an improvement over the sealed hand brake arrangement shown in my application, Ser. No. 869,534, filed Oct. 27, 1969.

Hand brakes for railroad cars as part of their operational environment are fully exposed elements which means that fouling due to moisture and dirt is a common occurrence. This is particularly true of hand brakes arranged for under the car application where they are exposed to the debris of dust, mud, snow, and the like that is made airbourne by movement of the car ad its wheels.

Nevertheless, the sealing off of vital parts of the hand brake from exposure to the elements is made difficult by the fact that the hand brake chain must be able to move freely from its drum on full release, and the operating and release shafts of the brake need to be controlled exteriorly of the brake housing to provide the simplified mechanical control over their functions that railroad car hand brakes require.

A principal object of this invention is to provide a sealed hand brake arrangement of the non-spin type that is readily applicable to hand brake designs of the under the car application as well as those designs for mounting at the sides or ends of the car above the floor level, and does not interfere with the desired mechanical control over the hand brake vital functions.

Another principal object of the invention is to provide a mounting arrangement for the drum of the hand brake that permits ready running on and running off of the brake chain while providing for the sealing off of the other critical parts of the brake.

A further principal object of the invention is to provide a chain stop arrangement for handbrakes that prevents winding up of the brake chain in the wrong direction and overtravel of the drum on full release (which adversely effects brake shoe positioning).

Other objects of the invention are to provide a sealed hand brake arrangement of the non-spin type that includes an improved winding drum end drum cover arrangement, and that is economical of manufacture, convenient to install and operate, and long lived and reliable in operation.

Further objects, uses, and advantages will be obvious or become apparent from a consideration of the following detailed description and the application drawings, in which like reference numerals indicate like parts throughout the several views.

In the drawings:

FIG. 1 is a vertical sectional view of a vertical hand wheel type hand brake in which the improvements of my invention have been embodied, with some parts shown in elevation, and with the brake shown with the chain unwound and in condition for winding the chain on the brake drum;

FIG. 2 is a front elevational view of the hand brake shown in FIG. 1, with parts broken away to expose other parts, and with the hand brake release handle being partially shown in its two operating positions in broken lines;

FIG. 3 is a view similar to that of FIG. 1 illustrating the improvements of my invention applied to a hand brake of the under the car application type;

FIG. 4 is a fragmental front elevational view showing a modification of the embodiment of FIGS. 1 and 2 for adapting same for a different type of hand brake application; and

FIG. 5 is a view similar to that of FIG. 4 but showing the embodiment of FIG. 3 arranged for a modified type of under the car application.

However, it is to be understood that the specific drawing illustrations provided are supplied primarily to comply with the requirements of the Patent Code, and that the invention may have other specific embodiments that will be obvious to those skilled in the art.

Reference numeral 10 of FIGS. 1 and 2 indicates one embodiment of the invention in the form of a vertical hand wheel hand brake positioned as it would be applied to a railroad car, in which the brake operating mechanism is indicated at 12 and is contained in a housing 11. While reference may be had to Natschke and Macku U.S. Pat. No. 3,390,590 for the specifics of a hand brake operating mechanism of the general type illustrated, the hand brake details will be described to some extent herein to insure a complete understanding of the structural features involved.

The housing is in two sections comprising a front casing 14 and a back section or attaching plate 16, the latter defining a body portion 18 formed with a pair of lower indentations 20 each which is formed with a bolt hole 22. The attaching plate 16 is also formed with a pair of upper indentations 23 each including a bolt hole 24, and bolt holes 22 and 24 are adapted to receive appropriate attachment bolts or the like to secure the back plate or section to the car in a conventional manner.

The front casing 14 is secured to the back section or attaching plate by appropriate bolts indicated at 26 that respectively pass through the respective suitable upper and lower flange enlargements 27 and 29 of the front casing on either side of same. The major portion of the brake operating mechanism is mounted within this casing and in such a manner as to be removable with it.

The brake operating mechanism 12 includes brake drum 30 to which is attached brake chain 49, a drum gear 34 that meshes with a pinion 62 journaled on a reduced portion 64 of operating shaft 66 to which the hand wheel 68 is suitably keyed. In the form shown, the operating shaft 66 is formed with an outwardly extending tapered portion 69 of square section on which the hand wheel 68 is received and against which the hand wheel is clamped by appropriate nut 70 or other suitable restraining means.

The operating shaft 66 includes the enlarged portions 72 and 74 (FIG. 1) which are respectively journaled in brass bushing 76 and phosphorus bronze bushing 78 received in the housing casing and back plate, respectively. The brass bushing sleeve 76 is received in a dished bearing retainer 80 that is received in opening 81 of the attaching plate 16, while bushing 78 is applied directly to an opening 82 of housing section 14 by being pressed directly into same.

As indicated in FIG. 1, the pinion 62 comprises a gear portion 90 and a clutch collar portion 92 formed with a conical friction face 94 that is intended to cooperate with a similarly formed friction face 95 of ratchet wheel 96. The other side of the ratchet wheel 96 is formed with a similar friction face 98 that is intended to cooperate with friction face 100 of nut 102 that is threadedly mounted on a threaded portion 104 of pinion 62. In the form illustrated, friction surfaces 94 and 95, and 98 and 100, are separated by annular brass cone members 99 that complement the respective surfaces they are between and are free to float with respect thereto.

Operating shaft 66 is formed with a hex shaped portion 106 on which is slidably mounted a jaw clutch sleeve 108 provided with jaws 110 that are proportioned and spaced to fit into recesses 112 formed in the face 114 of nut 102 which define cooperating teeth of the nut that complete the tooth or jaw clutch between the operating shaft 66 and the nut 102 that is generally indicated at 118.

The clutch sleeve 108 is provided with a radial flange 120 which is engaged by a grooved cam member 122 keyed to release handle shaft 124 that is journaled between the casing 14 and a bracket plate 126 which is suitably mounted therein. Cam member 122 includes a hub portion 130 that is received over the shaft 124 and is formed with spaced indentations 132 that receive the similarly spaced projections 133 of the hub portion 134 of release handle 136 that is affixed to shaft 124 in any suitable manner.

The cam member 122 is formed with a rim portion 142 defining a camming groove 144 in which the radial flange 120 of the clutch sleeve 108 is mounted. The camming groove 144 is given the configuration that will move the teeth 110 of clutch sleeve 108 from recesses 112 of nut 102 as release handle 136 is moved from the lower broken line position of FIG. 2 to the upper broken line position of that figure (the latter is the full brake release position).

Also controlled by the release handle 136 is a pawl 150 (see FIG. 2) that is slidably mounted on support plate 152 affixed to the bracket plate 126 in any suitable manner, which pawl 150 engages in the teeth 154 of ratchet wheel 96. Pawl 150 is provided with an opening in which is received the end 158 of operating arm or finger 160 that is journaled by a headed pin 162 between the plate 126 and the supplemental bracket plate 164 mounted within the front casing 14.

Also mounted on the release handle shaft 124 is a holding pawl stop member 166 which is in the form of a sleeve portion 168 and a pawl engaging arm 170. The sleeve 168 is rotatably mounted on the release shaft 124 and is provided with a pair of spaced apart shoulders that are about 180 degrees apart that are not shown in the drawings but are clearly illustrated in said U.S. Pat. No. 3,390,590; as described in said U.S. Pat. No. 3,390,590, one of these shoulders is engaged by a shoulder of the shaft 124 to hold the pawl engaging stop member 166 in engagement with the pawl 150 in the brake holding position of the shaft 124 when the release handle 136 is in its brake holding position. The shaft 124 is also formed with a shoulder positioned to engage the other shoulder of sleeve 168 to move the pawl engaging stop member 166 out of engagement with the pawl 150 as the release handle is moved to the upper position of FIG. 2.

As indicated, the brake release mechanism shown is essentially the same as that described in said U.S. Pat. No. 3,390,590. The parts associated with pawl 150 are so constructed that when the release handle 136 is in the lower position of FIG. 2, one of the aforementioned shoulders of release shaft 124 (shown at 178 in said Natschke and Macku patent) will engage a corresponding shoulder (shown at 172 in said Natschke and Macku patent) of the sleeve 168 thereby holding the pawl stop arm 170 in the position shown in FIG. 2 against the pawl 150, which will thus be held against partial rotation. In such position, the ratchet wheel 96 is held from rotating in the direction that will release the brake (that is, a counterclockwise direction in the showing of FIG. 2). But when the ratchet wheel is moved through the hand wheel 68 and the intervening clutch device in the direction that is clockwise of FIG. 2, the inclined surfaces 190 of the ratchet wheel teeth 154 will engage the inclined surface 192 of the pawl 150, thereby causing the pawl 150 to slide upwardly lengthwise of its axis until the tooth involved is past the pawl 150, whereupon the pawl 150 will drop by gravity into the space between the next adjacent teeth for abutting engagement with the next tooth surface 189.

In the specific hand brake arrangement that is shown in FIGS. 1 and 2, the front casing 14 is indented inwardly as at 200 (see FIG. 1) to define an operating space 202 exteriorly thereof that is substantially within the plane of the front casing, in which the brake drum 30 is mounted for purposes of disposing the brake drum 30 and its chain 49 exteriorly of the space 204 that is enclosed by front casing 14 and the rear mounting plate 16. Casing 14 thus defines a shoulder 205 at one side of operating space 202.

For purposes of sealing off such space 204 and the mechanisms enclosed therein from the elements, the front casing 14 is flanged as at 206 about its rim 208, which flange portion is shaped to define the enlargements 27 and 29 and is indented as at 210 to define a recess 212 which is in circumambient relation about the front casing 14. Mounted within the groove 212 is a seal element 214 of any suitable type, as for example a length of O-ring type material cut to fit within the groove 212 and fill same with the ends thereof abutted. The seal element 214 is proportioned so that when the casing 14 is applied against the surface 216 of the back section 16, the seal engages both the front casing and the mounting plate, whereby when the front casing 14 is affixed to the mounted plate by bolts 26, the seal element 214 will be clamped into firm sealing engagement with both the casing and the mounting plate.

While the seal element 214 may be made in the form of an endless element exactly proportioned to fit into the groove 214, for reasons of economy I prefer that the sealing element may be cut to the desired length from a bulk supply of such material in strand form. If desired, the cut ends instead of merely being in abutting relation can be spliced together or otherwise overlapped to insure a complete seal all the way about the rim of the casing 14.

Brake drum 30 in the form illustrated is of the single wind type and comprises a one piece hub member 220 defining spaced ribs 222 which are flanged as at 224 to define a seat for alternate chain links when the chain is wound up on the drum. The other alternate links are partially disposed in the annular recess 223 defined by ribs 222. The ribs 222 are enlarged radially as at 226 and are formed with holes 227 in the respective enlargements 226 that receive the pin 228 that secures the brake chain 49 to the brake drum. Pin 228 includes a shank 231 and a head 229 that has the special function referred to hereinafter.

The brake drum 30 is secured in its operating space 202 by being mounted on brake drum shaft 230, which includes a hub carrying portion 232 of polygonal configuration on which the brake drum hub portion 220 fits, the hub portion 220 defining a bore 234 that is proportioned to substantially complement the configuration of the shaft portion 232.

The brake drum shaft 230 is journaled between the indented portion of the front casing 14 and a brake drum cover plate 236 that is secured to the casing 14 over the brake drum, as by welding or employing suitable bolts 238 cooperating with nuts 240 (see FIG. 1) that are fixed in place, as by welding, to the inner surface of casing 14 in the positions indicated in FIG. 2. Cover plate 236 includes a pair of bolt receiving flanges 239 for this purpose.

The brake drum shaft 230 includes an enlarged portion 242 which is journaled in brass bushing 244 that is pressed into the opening 246 of annular mounting member 247 that is press fitted into opening 249 formed in the casing 14 for mounting member 247.

Shaft 230 includes an extension 248 to which the drum gear 34 is affixed, as by welding at 250. Extension 248 may be of polygonal configuration designed to be complementarily received within a corresponding polygonal bore 252 formed in the gear 34. Gear 34 includes diaphragm portion 251 and rim portion 253 that is formed with gear teeth 255 adapted to mesh with pinion 62.

At the other end of the shaft 230, extension 254 is journaled in a brass bushing 256 received in a cup 258 that is in turn received in opening 260 formed in drum cover plate 236 for this purpose.

The drum hub portion 220 is proportioned longitudinally of shaft portion 232 so that its ends 264 and 266 substantially overlie such shaft portion 232. Shaft extension 254 engaging the cup 258 prevents movement of the drum shaft 230 to the right of FIG. 1, while shaft extension 248 engages the attaching plate 16 to prevent more than a predetermined amount of movement of the gear 34 in the direction of mounting plate 16.

With the brake drum and its shaft arranged and journaled as indicated, the drum gear 34 can be mounted completely within the sealed off space 204 of the housing 11 while the brake drum 30 itself is disposed exteriorly of the casing 14 to permit the brake chain 49 to be readily wound up on the drum, or to run off from same on release of the brake.

Drum cover plate 236 is dished in a manner similar to the upper portion of casing 14 to enclose the operating space 202 except in the area of operation of the brake chain 49 where the edge portion 270 of the drum cover 236 and the indented portion of the casing 14 define an opening 272 in which the brake chain operates. Cover plate 236 defines a rounded end portion 271 and a rectilinear end portion 273 (at edge portion 270), and is flanged as at 239 along and extending laterally of side edges 275. In the forms of FIGS. 1- 3, rounded end portion is recessed as at 277 for close fitting relation with casing shoulder 205, to which cover plate 236 is affixed, as by welding at 279.

Fixed to the front casing 14 in operating space 200 is a stop block 181 that comprises a block of metal fixed to casing 14 in the position indicated in FIGS. 1 and 2, as by welding. Block 181 is thus disposed in the path of movement of head 229 of chain anchor pin 228 and defines planar surface 283 which is engaged by head 229 to stop movement of drum 30 in the chain unwinding direction, either after quick release of the brakes, or when the operator inadvertently attempts to wind up the chain in the wrong direction. The stopping of the drum at the full unwound position of FIG. 2 prevents inertia tendencies (to rewind the chain in the wrong direction) from adversely effecting brake shoe spacing.

In operation, assuming that the hand brake 10 is released the normal inoperative position of the release handle 136 will be positioned in the lower position of FIG. 2, which brings the teeth of clutch sleeve 108 into engagement with the teeth receiving recesses 212 of nut 102 and biases pawl 150 toward the ratchet wheel 96. Rotation of the hand wheel 68 in the direction to wind up the brake (clockwise of FIG. 2) will turn nut 102 towards clutch collar 92 of pinion 62 and bind the ratchet wheel 96, the pinion 62, and the operating shaft 66 into one rotating unit which will rotate the drum 30 in the direction to wind up the brake (see the arrow of FIG. 2). During this operation, the pawl 150 moves back and forth under the action of teeth 54 and gravity until the brake is set. The release handle remains in the lower position 136 so that when the brake is wound up and the pawl is returned to its full lined position of FIG. 2, the brake is fully set.

The chain 49 in winding on the drum 30 winds up in the plane of recess 223, and thus the drum is of the single wind type. Alternate links 241 of the chain lie within the recess 223, while the other alternating links 243 sequentially are engaged by the peripheries of ridges 222 until such ridges are covered, the succeeding chain links then winding up on the first turn of links.

If it is desired to gradually release the brake, handle 68 is rotated in a counterclockwise direction (with reference to the showing of FIG. 2) a slight amount, which will have the effect of loosening nut 102 and thus the clutching surfaces between the ratchet wheel and pinion 62 so that the pinion 62 and shaft 66 will rotate with respect to the ratchet wheel under the control of the operator, who by slight loosening or tightening movements can increase or decrease the friction drag on the rotational movement on the pinion 62, thus fully control brake release.

When it is desired to provide a free release of the brakes, the release handle 136 is moved from the lower position of FIG. 2 to the upper position of FIG. 2, which withdraws the teeth 110 of jaw clutch 118 from recesses 112 of nut 102 and moves pawl engaging arm 170 out of contact with the pawl so that the ratchet wheel pinion and drum freely rotate to release the brakes. As soon as the handle 136 is released, it automatically returns by gravity to its lower position of FIG. 2 since it cannot be raised beyond a vertical position. It is preferred that the amount of movement between the horizontal position of FIG. 2 and the upper position of the same figure be on the order of 84.degree. and a suitable stop pin of improvement type described in said Natschke and Macku patent (shown at 195 in that patent) in the path of movement of the cam member 122 provides for the release position of handle 136.

Referring now to the embodiment of FIG. 3, the hand brake 280 there illustrated comprises a housing 11A and brake operating mechanism 12A that are substantially identical to the housing 11 and brake operating mechanism 12 of the embodiment of FIGS. 1 and 2 (including its brake drum 30 and associated parts), as indicated by identical reference numerals indicating identical parts.

However, the brake 280 is arranged for an under the car application in the manner disclosed by Andonian U.S. Pat. No. 3,444,756, in accordance with which, the housing 11A is turned on its side and secured to the car underframe intermediate the sides of the car and between a pair of mounting plates (not shown but shown at 246 and 272 in said Andonian patent) that are respectively secured to the car sides, with the housing 11A extending longitudinally of the car. Journaled in the respective mounting plates are extensions for the hand brake operating and release shafts 66 and 124 that are each provided with operating handles exteriorly of the mounting plates and positioned relative to the car wheels so that the hand brake may be readily operated from either side of the car by the brakeman standing at ground level. The hand brake parts are oriented so that gravity aids the holding of the hand brake mechanism against release.

The sealing boot for the chain called for by the Andonian patent is not necessary in the arrangement of FIG. 3 by reason of the mounting of the brake drum 30 thereof in the manner indicated, that is, exteriorly of the sealed space 204A of the housing 11A.

As specifically illustrated in FIG. 3, the extensions for the hand brake operating and release shafts are in the form of shafts 17 and 19 that are described in said Andonian patent, while the extensions for the release shaft comprise shafts 25 and 27 that are shown in said Andonian patent.

In the case of the operating shaft 66A, in the embodiment of FIG. 3 it is provided at one of its ends with an extension 286 that is keyed to a coupling member 288 by a suitable pin 290, which coupling member 288 is secured to shaft 17 as by welding.

At its other end, the shaft 66A includes extension 292 which extends through the cup 80 and receives coupling member 294 to which it is keyed by a suitable pin 296. Shaft 19 is affixed to coupling member 294 as by welding. The enlargement 72 of shaft 66 is replaced by disc member 295 keyed to shaft 66A by pin 297.

In the case of the operating shaft 124A, the release handle 136 is eliminated, and in its place the release shaft 124A is extended as at 298 for reception in a coupling member 300 to which it is keyed by suitable pin 302. Coupling member 300 is fixed to shaft 25 as by welding.

At its other end, release shaft 124A is extended as at 304 for reception in coupling member 306 to which it is keyed by a suitable pin 308. Coupling member 306 is fixed to shaft 307 as by welding.

The hub member 133 of release member 136 is replaced by a corresponding hub member 133A that is affixed to shaft 124 in any suitable manner, as by employing suitable pin 310.

The hand brake 380 operates in the manner similar to hand brake 10 except that the hand wheels 21 and 23 and handles 29 and 31 described in said Andonian patent are manipulated to control the hand brake.

In the embodiment 320 of FIG. 4, the housing 11B and brake operating mechanism therein are similar to the corresponding housings 11 and 11A and operating mechanisms 12 and 12A of FIGS. 1- 3, with the brake mechanism being in an application in which the chain extends perpendicular to the brake mechanism plane that includes the axis of the operating shaft 66 or 66A and drum shaft 230. For applications of this type, the configuration of the drum cover plate 236A is such that in application it may be pivoted about the axis of shaft 230 to dispose its rectilinear side 273 perpendicular to the position brake chain 49 will take when under tension, such as that indicated in FIG. 5. In such case, the recess 277 of the forms of FIGS. 1- 3 is relocated to the side of the cover plate that will be adjacent casing shoulder 205 (where indicated at 279A), flange 239A being excised as necessary to accommodate shoulder 205, and cover plate 236A welded to shoulder 205 as at 279A. Cover plate may be secured in place by employing the bolts 238 of FIG. 2, or by welding, as at 322.

In the embodiment 324 of FIG. 5, the hand brake arrangement is of the type shown in FIG. 3 mounted to have the plane of the hand brake (that includes the axes of its shafts 66A and 230) at an angle of about 45.degree. relative to the horizontal, with the brake chain 49 extending substantially horizontal in the manner indicated in said Andonian U.S. Pat. No. 3,444,756. Drum cover plate 236B is relocated correspondingly with its recess 277B and excisement of flange 239B being also relocated in like manner for close fitting relation and welding to the casing shoulder. Again, cover plate 236B is fixed to casing by bolting or welding in the manner already indicated.

It will therefore be seen that I have provided a sealed hand brake arrangement which permits the vital working parts of the hand brake to be sealed against the elements while yet permitting adequate operating space for the brake chain winding and unwinding operations. The disclosed arrangement is also adapted for a wide variety of hand brake applications.

Claims

I claim:

1. In a sealed hand brake for railroad cars including a housing adapted to be mounted on a car, an operating shaft journaled in the housing, pinion and ratchet means mounted on the shaft with said pinion and ratchet means comprising a pinion rotatably mounted on the shaft and including a threaded portion, a nut mounted on the pinion threaded portion and a ratchet wheel rotatably mounted on the shaft between friction clutch faces of the pinion and nut, which ratchet wheel includes friction clutch faces on either side thereof adapted for cooperation with the friction clutch faces of the pinion and nut respectively to clutch the ratchet wheel against movement relative to the shaft, a jaw clutch keyed to said operating shaft and mounted for shifting movement axially of the shaft to clutch and unclutch with respect to said nut and turn same, when clutched thereto, relative to said pinion to provide a controlled release of the brake through clutching and unclutching of said clutch faces, brake holding means including pawl means mounted in said housing and cooperating with said ratchet means for holding said brake against release, hand operated release means for controlling said pawl means and including means for clutching and unclutching said jaw clutch to fully release the brake, a winding drum and cooperating drum gear meshing with said pinion, a brake chain having one end thereof connected by a chain anchor to the drum for winding up on the drum when the drum is rotated in its chain winding direction through said pinion and drum gear when said jaw clutch is clutched with said nut and said nut is rotated to clutch said ratchet wheel against rotation relative to said operating shaft, and means for rotating said operating shaft to wind up the chain on the brake drum through said pinion and drum gear, with said housing comprising a front casing and a back attaching plate secured together by bolt means and journaling said operating shaft and housing said pinion and ratchet means, said jaw clutch, said brake holding means, and said drum gear, and means for sealing the space enclosed by said front casing and said attaching plate including a seal element compressed therebetween, and said front casing adjacent said drum being indented inwardly of the housing to define a mounting space for said drum and a shoulder defining one side of said space, with the drum being positioned in said space, the improvement comprising:

a drum cover plate secured to said casing over said mounting space,

said drum cover plate comprising a dished member having a rounded end concentric with the drum and the opposite end of same being rectilinear,

a drum shaft,

means for journaling said drum shaft between said casing and said drum cover plate for rotation about an axis paralleling that of said operating shaft,

said drum and operating shaft axes lying in a plane that extends longitudinally of the housing,

said shaft including an end portion extending into said space between said casing and said attaching plate,

said drum gear being keyed to said drum shaft for rotation therewith,

the portion of the drum shaft within said drum mounting space being formed to define a polygonal configuration about the axis thereof,

said drum comprising:

a one piece drum hub member having a bore shaped to complement the configuration of said drum shaft portion, and being received on said shaft portion,

said drum member defining a pair of flanges spaced axially of said drum member,

with the chain anchor comprising a headed pin comprising a pin shank extending between said flanges and parallel to said axes with the end link of the chain received over said pin shank and between said flanges, and a head disposed adjacent said casing indentation,

said flanges being spaced to support alternate links on their rims when the chain is wound on the drum,

said rectilinear end of said drum cover plate being open and said chain one end extending rectilinearly from the drum through said drum cover plate open end with said pin positioned in aligned relation between said and the axis of the drum shaft in the unwound position of the chain.

and a chain stop comprising:

a stop block fixedly carried by the housing front casing indentation in said mounting space and positioned to be engaged by the head of said pin on release of the brake and stop unwinding overtravel of the chain anchor a predetermined amount beyond said aligned relation.

2. The improvement set forth in claim 1 wherein:

said drum cover plate rounded end is recessed for engagement with the front casing shoulder,

said drum cover plate rounded end being made fast to said casing at said recess thereof,

with said drum cover plate rectilinear end being disposed normally of said plane.

3. In a sealed hand brake for railroad cars including a housing adapted to be mounted on a car, an operating shaft journaled in the housing, pinion and ratchet means mounted on the shaft with said pinion and ratchet means comprising a pinion rotatably mounted on the shaft and including a threaded portion, a nut mounted on the pinion threaded portion and a ratched wheel rotatably mounted on the shaft between friction clutch faces of the pinion and nut, which ratchet wheel includes friction clutch faces on either side thereof adapted for cooperation with the friction clutch faces of the pinion and nut respectively, a jaw clutch shiftably keyed to said operating shaft and adapted to clutch and unclutch with respect to said nut and turn same, when clutched thereto, relative to said pinion to provide a controlled release of the brake through clutching and unclutching of said clutch faces, brake holding means including pawl means mounted in said housing and cooperating with said ratchet means for holding said brake against release, hand operated release means for controlling said pawl means and including means for clutching and unclutching said jaw clutch to fully release the brake, a winding drum and cooperating drum gear meshing with said pinion, a brake chain having one end thereof connected by a chain anchor to the drum for winding up on the drum when the drum is rotated in its chain winding direction, and means for rotating said operating shaft to wind up the chain on the brake drum through said pinion and drum gear, with said housing comprising a front casing and a back attaching plate secured together by bolt means and journaling said operating shaft and housing said pinion and ratchet means, said jaw clutch, said brake holding means, and said drum gear, and means for sealing the space enclosed by said front casing and said attaching plate including a seal element compressed therebetween, and said front casing adjacent said drum being indented inwardly of the housing to define a mounting space for said drum and a shoulder defining one side of said space, with the drum being positioned in said space, the improvement comprising:

a drum cover plate secured to said casing over said mounting space,

said drum cover plate comprising a dished member having a rounded end concentric with the drum and the opposite end of same being rectilinear,

a drum shaft,

means for journaling said drum shaft between said casing and said drum cover plate for rotation about an axis paralleling that of said operating shaft,

said drum and operating shaft axes lying in a plane that extends longitudinally of the housing,

said shaft including an end portion extending into said space between said casing and said attaching plate,

said drum gear being keyed to said drum shaft for rotation therewith,

the portion of the drum shaft within said drum mounting space being formed to define a polygonal configuration about the axis thereof,

said drum comprising:

a one piece drum hub member having a bore shaped to complement the configuration of said drum shaft portion, and being received on said shaft portion,

said drum member defining a pair of flanges spaced axially of said drum member,

with the chain anchor comprising a headed pin extending between said flanges and parallel to said axes with the end link of the chain received over said pin and between said flanges,

said flanges being spaced to support alternate links on their rims when the chain is wound on the drum,

said rectilinear end of said drum cover plate being open and said chain one end extending rectilinearly from the drum through said drum cover plate open end with said pin positioned in aligned relation between same and the axis of the drum shaft in the unwound position of the chain,

and a chain stop comprising:

a stop block carried by the housing and positioned to be engaged by the head of said pin on release of the brake and stop unwinding overtravel of the chain anchor a predetermined amount beyond said aligned relation,

said drum cover plate being fixed to said casing to dispose said rectilinear end thereof at a position relative to said plane that is other than perpendicular thereto.

4. In a sealed hand brake for railroad cars including a housing adapted to be mounted on a car, an operating shaft journaled in the housing, pinion and ratchet means mounted on the shaft with said pinion and ratchet means comprising a pinion rotatably mounted on the shaft and including a threaded portion, a nut mounted on the pinion threaded portion and a ratchet wheel rotatably mounted on the shaft between friction clutch faces of the pinion and nut, which ratchet wheel includes friction clutch faces on either side thereof adapted for cooperation with the friction clutch faces of the pinion and nut respectively, a jaw clutch shiftably keyed to said drive shaft and adapted to clutch and unclutch with respect to said nut and turn same, when clutched thereto, relative to said pinion to provide a controlled release of the brake through clutching and unclutching of said clutch faces, brake holding means including pawl means mounted in said housing and cooperating with said ratchet means for holding said brake against release, hand operated release means for controlling said pawl means and including means for clutching and unclutching said jaw clutch to fully release the brake, a winding drum and cooperating drum gear meshing with said pinion, a brake chain having one end thereof connected by a chain anchor to the drum for winding up on the drum when the drum is rotated in its chain winding direction, and means for rotating said operating shaft to wind up the chain on the brake drum through said pinion and drum gear, with said housing comprising a front casing and a back attaching plate secured together by bolt means and journaling said operating shaft and housing said pinion and ratchet means, said jaw clutch, said brake holding means, and said drum gear, and means for sealing the space enclosed by said front casing and said attaching plate including a seal element compressed therebetween, and said front casing adjacent said drum being indented inwardly of the housing to define a mounting space for said drum and a shoulder defining one side of said space, with the drum being positioned in said space, the improvement comprising:

a drum cover plate secured to said casing over said mounting space,

said drum cover plate comprising a dished member having a rounded end concentric with the drum and the opposite end of same being rectilinear,

a drum shaft,

means for journaling said drum shaft between said casing and said drum cover plate for rotation about an axis paralleling that of said operating shaft,

said drum and operating shaft axes lying in a plane that extends longitudinally of the housing,

said shaft including an end portion extending into said space between said casing and said attaching plate,

said drum gear being keyed to said drum shaft for rotation therewith,

the portion of the drum shaft within said drum mounting space being formed to define a polygonal configuration about the axis thereof,

said drum comprising:

a one piece drum hub member having a bore shaped to complement the configuration of said drum shaft portion, and being received on said shaft portion,

said drum member defining a pair of flanges spaced axially of said drum member,

with the chain anchor comprising a headed pin extending between said flanges and parallel to said axes with the end link of the chain received over said pin and between said flanges,

said flanges being spaced to support alternate links on their rims when the chain is wound on the drum,

said rectilinear end of said drum cover plate being open and said chain one end extending rectilinearly from the drum through said drum cover plate open end with said pin positioned in aligned relation between same and the axis of the drum shaft in the unwound position of the chain,

and a chain stop comprising:

a stop block carried by the housing and positioned to be engaged by the head of said pin on release of the brake and stop unwinding overtravel of the chain anchor a predetermined amount beyond said aligned relation,

said hand brake being formed to be of the under the car application type,

with said rectilinear end of said drum cover plate disposed diagonally of said plane.