US3511347A - Automatic brake releasing means - Google Patents

Description

' May 12, 1970 Fiied Feb. 8, 1968 w. T; PRITCHARD AUTOMATIC BRAKE RELEASING MEANS 2 Sheets- Sheet 1 INVENTOR WILLIAM TI Pzrrcamzo O MMQ ATTORNEYS Maw All? SUPPLY May 12; 1970 w. T. PRITCHARD ,511,

AUTOMATIC BRAKE RELEASING MEANS Filed Feb. 8, 19 68 2 Sheets-Sheet 2 llllllllllllllllllllllllfi 'lllilm I I L P 23 if tg a 'lgA M- I I 7 54 5e 3 I'NVENTOR WlLLlAM T Pczrro-mrzo ATTORNEYS United States Patent O 3,511,347 AUTOMATIC BRAKE RELEASING MEANS William T. Pritchard, Beckley, W. Va., assignor of onefourth each to John C. Ashworth and Robert J. Ashworth, both of Beckley, W. Va.

Filed Feb. 8, 1968, Ser. No. 703,940 Int. Cl. F16d 65/32; F16h 21/44 US. Cl. 188-216 8 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION This invention is related to the field of braking apparatus and is specifically related to the field of railway train braking systems and is specifically directed to means for automatically deactivating the mechanical brakes of a railroad car upon connection of the car to the compressed air line of a train.

Railroad cars are provided with mechanical brakes which are actuated by means of a brake-setting handwheel assembly usually located adjacent one end of the car. When a railroad car is parked on a siding, it is necessary to set the mechanical brakes in order to insure that the car will remain in its parked position. Therefore, when it is desired to move the car, it is necessary that the mechanical brakes be released, This releasing operation requires a great deal of physical exertion on the part of the brakeman and it is also quite time consuming. Moreover, the problem is greatly aggravated when there are a large number of cars which must be released and it sometimes occurs that all of the mechanical brakes will not be released so as to result in sliding of the car wheels along the track when the cars are connected to a locomotive. Also, it sometimes occurs that the brakes are not completely released and, while the wheels do not drag, there is a resultant wear and tear upon the braking system and the rails. For these reasons, it is highly desirable that means be provided for automatically releasing the mechanical brakes of a railroad car upon connecting of the car to other cars or locomotives prior to movement of the car from its parked position.

SUMMARY OF THE INVENTION Therefore, it is the primary object of this invention to provide means for automatically releasing the mechanical hand-set brakes of a railroad car upon connection of the car to the main compressed air supply line of another car or of a locomotive.

The primary object of this invention is obtained by the provision of a pneumatic cylinder mounted on the car adjacent the conventional mechanical brake-setting handwheel assembly of the car. This pneumatic cylinder is provided with a rack attached to the end of the piston rod of the cylinder and the cylinder is connected to a line connected to the main air supply coupling of the car. When the main air line supply coupling is connected to the compressed air line of another car, the cylinder is actuated to extend the piston so that the rack engages a gear mounted on the handwheel supporting shaft of the manual brake-setting means. Engagement of the rack with the gear serves to rotate the manual setting means in a direction to release the mecahnical brakes so that the car can then be moved without brake or wheel dragging. A

3,511,347 Patented May 12, 1970 shutoff valve is provided in the air line connecting the cylinder with the main air supply coupling in order to prevent activation of the cylinder is such as desired. Moreover, the means supporting the pneumatic cylinder is adjustable so that the position of the cylinder can be adjusted.

DESCRIPTION OF THE DRAWINGS FIG.1 is a perspective view of the preferred embodiment of the subject invention mounted on the end of a railway car;

FIG. 2 is a partial sectional view taken along lines 2--2 of FIG. 1;

FIG. 3 is a partial sectional view substantially identical with FIG. 2 but illustrating the parts in a different operative relationship with respect to each other; and

FIG. 4 is a sectional view taken along lines 44 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT The preferred embodiment of this invention is perspectively illustrated in FIG. 1 as installed on the end of a railway car 20. The car is provided with a conventional linkage system consisting of a vertical link 22 connected to the upper arm of a right angle pivot lever 24 pivotally attached to the frame of the car. The upper end of link 22 is connected by a chain 26 which extends into a conventional brake actuator housing 28 which contains rotary means for raising and lowering the chain. A horizontal link 30 extends between the lower arm of pivot lever 24 and the mechanical brakes of the car (not shown) so that lifting movement of chain 26 and rod 22 serves to move the horizontal link 30 so as to set or engage the mechanical brakes of the car. Chain 26 is raised or lowered by rotation of a brake-setting wheel 32 which is fixed to a shaft 34 extending from housing 28. The aforediscussed construction is conventional and while the prior art constructions employ various minor variations, all of the known mechanical brake-setting devices employ a shaft mounted rotatable wheel such as wheel 32 for setting the brakes.

Therefore, the prior known devices require a manual operation of the setting wheel 32 in order to effect setting of the brakes and similarly require a manual operation for disengaging the brakes when it is desired to move the. car. This invention avoids the necessity of the latter operation.

Turning now to FIG. 1, it will be seen that this invention includes a support means or bracket 36 fixedly attached to the end wall of the railroad car 20, First and second U-shaped bolts 38 and 40 have their outer ends extending through apertures in support means 36 and are retained in place by nuts 42 and 44 respectively. The apertures through which bolts 38 and 40 extend can be in the form of slots to permit adjustment of the bolts. The U-shaped bolts 38 and 40 clamp a pneumatic cylinder 46 in a desired adjustably fixed relationship with respect to the support means 36 when nuts 42 and 44 are tightened.

A piston 48 is contained within cylinder 46 for reciprocation in a conventional manner and a piston rod 50 extends outwardly from one end of the cylinder through a slide bearing 52. A small bleed hole 53 is provided adjacent slide bearing 53 for the purpose of controlling the speed with which the piston 48 moves. The other end of pneumatic cylinder 46 is provided with a port 54 to allow the entry of compressed air to the interior of the cylinder. An air line 56 is connected to port 54 as shown in FIG. 2 and is provided with a gate valve 58. The side of gate valve 58 opposite to the connection to pneumatic cylinder 46 extends downwardly for connection to the main air supply coupling (not shown) of the car 20. When the car is connected to another car, the main air supply coupling is connected to a like coupling on the other car so that compressed air will consequently be provided to line 56 so as to actuate cylinder 46 and cause piston 48 to move so as to extend piston rod 50 from the cylinder 46. Obviously, when valve 58 is closed, compressed air cannot reach the pneumatic cylinder 46 to actuate the cylinder.

The outer end of rod 50 has a rack member 60 pivotally attached thereto by means of pivot means 62. The lower end of rack 60 is provided with a plurality of teeth 64 which engage a gear wheel 66. While gravitational urging has proven adequate for maintaining teeth 64 in engagement with gear 66, a supplemental biasing spring can be provided to engage the top of rack 60 for this purpose if desired. Gear wheel 66 is mounted in a supplemental gear housing 67 fixed to shaft 34 so that rotation of the gear wheel rotates the shaft to consequently move chain 26, link 22 etc. so as to affect the brake setting. Housing 67 is provided with slots on either side enabling entry and movement of rack 60 in an obvious manner as shown in FIG. 3.

A coil spring 70 is provided on the interior of cylinder 46 in encircling arrangement with piston rod 50 as illustrated in FIG. 4. The coil spring 70 serves to bias the piston 48 to the right in an obvious manner.

When the manual brakes of a railway car are to be set, handwheel 32 is rotated to its extreme clockwise position and the parts assume the position illustrated in FIG. 2 with the piston and piston rod assembly being in its extreme rightward position. It should be noted that the piston assembly will return to its rightmost position at the time the air coupling of the car is disconnected from the source of compressed air with spring 70 providing the motive force for returning the piston to the position illustrated in FIG. 4. The teeth on rack 60 are shaped so that the rack teeth will ride over gear wheel 66 during rack movement from left to right as will be obvious from inspection of the rack teeth and gear teeth in FIG. 3. However, it sometimes occurs that the mechanical linkage for setting the brakes contains an excessive amount of play and it may be necessary to provide additional rotation of handwheel 32 and gear 66 to complete setting of the mechanical brakes when the parts are in the position illustrated in FIG. 3. Obviously, engagement of teeth 64 on rack 60 would preclude the additional rotative movement necessary for the handwheel 32 and gear 66. Therefore, in such situations, rack 60 is pivoted counterclockwise upwardly so that teeth 64 are disengaged from gear 66 to enable the completion of the setting of the manual brakes without interference from gear teeth 64. A pivotable stop or latch can be provided on the end of the car for holding the rack in this upward position if such is desired. Such a latch could be in the form of a pivot plate pivotally connected to the end of the car beneath rack 60' so as to be pivoted upwardly beneath the rack to lift same. An abutment extending downwardly from the bottom of the rack so as to engage the pivot latch upon actuation of cylinder 46 would serve to pivot the latch out of supporting relationship with respect to the rack so that the rack would move downwardly to engage gear 66 upon actuation of cylinder 46.

Therefore, when the railway car is in a parked condition, with the mechanical manually actuated brakes set, the parts are in the position illustrated in FIG. 2. However, when it is desired to move the car, it is coupled to an adjacent car or locomotive for movement. Coupling of the car to an adjacent car requires connection of the air hose coupling to the air hose coupling of the adjacent car and this connection supplies compressed air through lines 56 to actuate cylinder 46. Consequently, the cylinder is actuated to move the piston rod and piston assembly to its leftward extended position illustrated in FIG. 3. This movement causes gear teeth 64 to rotate gear 66 to release the manually set mechanical brakes in an obvious manner. The bleed hole 53 controls the rate of movement of the piston and piston rod assembly in an obvious manner.

When the car is subsequently parked, the air coupling will be disconnected so that spring 70 will return the piston to the position illustrated in FIGS. 2 and 4. The shape of the teeth 64 is such to enable this movement as was discussed previously. The brakes can then be mechanically set by rotation of handwheel 32. However, in some instances it might be desirable to set the mechanical brakes prior to disconnection of the air coupling. In which cases, rack 60 could be pivoted upwardly so that teeth 64 are disengaged with gear wheel 66 so as to allow rotation of handwheel 32 to effect setting of the manually set mechanical brakes without interference from teeth 64.

What is claimed is:

1. In a railroad car of the type having manually set mechanical brakes which are set by rotation of a shaftmounted brake-setting wheel, the invention comprising an improved releasing means automatically actuated by connection of the compressed air line of the railroad car to a source of compressed air, said brake releasing means including an air cylinder containing a piston and extendable piston rod, rack means connected to the end of said piston rod, gear means on said shaft engaged with said rack, a compressed air supply line connected between said cylinder and the main air supply coupling of the car and supporting means supportingly attached said cylinder to said railroad car in a position adjacent said brakesetting wheel so that connection of the compressed air line to said source of compressed air causes said cylinder to be actuated to extend said cylinder to rotate said gear wheel mounted on said shaft on which said brake-setting wheel is mounted to consequently release the mechanical brakes.

2. The invention of claim 1 wherein said rack means is attached to the end of said piston rod by means of a pivot connection for permitting said rack to be pivoted out of engagement with said gear wheel.

3. The invention of claim 2 additionally including valve means in said compressed air supply line actuable when closed to prevent automatic operation of said brake releasing means.

4. The invention of claim 3 additionally including spring means within said cylinder for biassing said piston and piston rod in a direction opposite to the direction of movement of said piston and piston rod when said piston is actuated by compressed air.

5. The invention of claim 4 wherein said supporting means includes means enabling the adjustment of the position of said cylinder with respect to said gear wheel.

6. The invention of claim 2 wherein said gear wheel is mounted on a horizontal shaft and said rack is pulled downward by the force of gravity into engagement with said gear but is pivotable upwardly against the force of gravity out of engagement with said gear.

7. The invention of claim 6 additionally including valve means in said compressed air supply line actuable when closed to prevent automatic operation of said brake releasing means.

8. The invention of claim 7 additionally including spring means within said cylinder for biassing said piston and piston rod in a direction opposite to the direction of movement of said piston and piston rod when said piston is actuated by compressed air.

References Cited UNITED STATES PATENTS 1,459,650 6/1923 Burnett 74109 X 1,819,952 8/1931 Fink l88216 DUANE A. REGER, Primary Examiner US. Cl. X.R.

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