MXPA01001950A - Spring-action parking brake assembly - Google Patents

Abstract

To provide a spring-action parking brake assembly for trains automatically started when a rolling stock is disconnected from a pneumatic braking system of a train. SOLUTION:In this spring-action parking brake assembly 60, a braking system is provided with a casing 67 attached on a side of an air cylinder. The casing contains a spring member 68 and a piston assembly 70, and these are so fitted that they can move longitudinally in the casing when air pressure is applied into or removed from the casing. The piston assembly 70 includes a piston rod 62 connected to a force distribution lever of the braking system. When air pressure in the casing is removed, the piston rod moves longitudinally, thereby turning the force distribution lever. The force distribution lever applies force to at lease one force transmission member in a train braking system to start braking. The spring-action parking brake assembly 60 is also provided with a device for installing it in the train braking system.

Description

PARKING BRAKE ASSEMBLY APPLIED WITH SPRING FIELD OF THE INVENTION The present invention relates, in general, to a parking brake assembly for use in a railway vehicle brake system and more particularly, this invention relates to a parking brake assembly applied with spring for use in a rail vehicle brake system that is activated by the absence of air in the rail vehicle brake system and, even more specifically, the present invention relates to a parking brake assembly applied with Dock for use in new brake assembly mounted on railway wagon.

BACKGROUND OF THE INVENTION As is generally well known in the railway industry, when rail cars are removed from a train and parked in a siding, or yard, the handbrake or parking brake is applied in at least some of these wagons as a precaution against the unwanted and unexpected movement of wagons. A typical railcar handbrake system consists of an apparatus for manually applying and pushing one or more brake shoes against the tread of one or more wheels of the railcar either by rotating a handwheel or by pumping a ratchet handle in a handbrake mechanism attached to the railcar. As illustrated in Figure 3, in truck mounted brake systems, the hand brake mechanism is usually either a molded or stamped metal gear housing usually attached to a terminal outer wall of the rail car. This handbrake mechanism has a chain drum rotatable therein that can be rotated by turning the handwheel to wind a brake chain in the chain drum. The other end of the brake chain normally extends through the bottom of the gear housing and is interconnected with a cable, or other articulation such as a handbrake lever, to the brake beam carrying the brake shoes as that the winding of the brake chain in the chain drum will apply tension to the brake chain and joints as necessary to pull the brake shoes interconnected against the surfaces of the tread of the adjacent wheels of the rail car and consequently , apply as the handbrake is proposed. A disadvantage of this type of hand brake arrangement of the prior art is that the Operator must be sure that the handwheel is rotated at least in an amount sufficient to ensure that the parking brake engages. Also, there is a possibility that the operator may forget to fully apply the brake, which could result in an unexpected movement of the rail car when it is parked in the siding or yard. In addition, the operation of the handwheel requires that a considerable amount of physical force be exerted from a complicated position. This, in turn, makes the application of the handbrake difficult.

SUMMARY OF THE INVENTION Briefly, the invention comprises a liner that is mounted on or within the brake system, typically adjacent to the air cylinder. This liner contains a spring member and a piston assembly, both of which are mounted for longitudinal movement within the liner. One end of the spring member contacts or is capable of pushing against an inner surface of the liner. The opposite end of the spring member is associated with the piston assembly such that the piston assembly moves in accordance with the movement of the spring member. The piston assembly includes a piston rod associated therewith which also moves in accordance with the movement of the spring member. The piston rod is attached to, or is associated with, the lever force transfer of the brake system such that the longitudinal movement of the piston rod causes this force transfer lever to rotate and apply a force to at least one force transmission member in the vehicle brake system to initiate the application of the brake. The air pressure from the pneumatic brake system causes the spring to retain a compressed condition while the railcar is in the position within which it constitutes the train. In the removal of this train railway wagon and consequently the pneumatic brake system, the spring automatically extends to its natural position to initiate the braking sequence. The invention also includes the arrangement or system for installing the spring loaded parking spring assembly within a rail vehicle brake system. This arrangement comprises a tubular member mounted for longitudinal movement within the liner. The tubular member is also associated with the piston assembly and the spring member and moves in accordance with the movement of the piston assembly and the spring member. The liner includes an opening at one end and the tubular member can extend through this opening when the piston assembly and the spring member move in a direction to compress the spring member. A means of retaining to retain the portion of the tubular member extending through the opening in place so that the spring member is maintained in the compressed position which causes the spring applied brake assembly to be in a deactivated position. Accordingly, the parking brake assembly applied with spring can be maintained in this deactivated position during installation within the rail vehicle brake system. Additionally, this retaining means may be employed to retain the spring applied parking brake assembly in a deactivated position if for any reason it is desired that the parking brake in the car remain deactivated after removal of the brake system carriage. Railway vehicle tire.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a spring applied parking brake assembly for a rail vehicle brake system that is an ergonomic alternative to commonly used and normally active hand brake assemblies. Another object of the present invention is to provide a spring applied parking brake assembly that is particularly applicable to a truck-mounted brake system.

Yet another object of the present invention is to provide a spring-applied parking brake assembly that can be used to replace hand-held, hand-held, hand-activated and hand-operated brakes. It is a further object of the present invention to provide a spring applied parking brake assembly for a rail vehicle brake system that is activated by the absence of air in the braking system ensuring that the parking brake is activated as soon as possible. the wagon has been removed from the train's air brake system. Still another object of the present invention is to provide a spring applied parking brake assembly for a rail vehicle brake system which, if necessary, can be mechanically deactivated. It is still a further object of the present invention to provide a spring applied parking brake assembly for a railway vehicle brake system which by virtue of being automatically activated in the removal of the rail car from the train's air brake system will eliminate the possibility of operator error when applying the parking brake. It is another object of the present invention to provide an arrangement or system for installing the Parking braking assembly applied with spring inside a rail vehicle brake system. Although various objects and advantages of the present invention have been described in some detail above, the various additional objects and advantages of the spring applied parking brake assembly of the present invention will become more readily apparent to those skilled in the art. From the following more detailed description of the invention, particularly, when this detailed description of the invention is taken in conjunction with the attached figures of the drawings and with the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a plan view showing a wagon mounted brake assembly including a parking brake assembly applied by means of the present invention. Figure 2 is a front view of the wagon-mounted brake assembly of Figure 1 including the parking brake assembly applied with spring. Figure 3 is a plan view showing a wagon-mounted brake assembly having a conventional hand-wheel handbrake of the prior art or parking brake, as described above, and which is therefore marked, "prior art". Figure 4 is a sectional view of the spring applied parking brake assembly of Figure 1 with the spring member in a compressed position and the piston assembly in a released position. Figure 5 is an expanded, partial view illustrating a portion of the installation arrangement, including an exemplary means for retaining the spring in a compressed position, for the spring applied parking brake assembly of Figure 1.

DETAILED DESCRIPTION OF THE INVENTION Before proceeding with the more detailed description of the present invention, a description of a wagon-mounted brake system and its operation should be useful in understanding the present invention. Also, it should be noted that for reasons of clarity, the identical components that have identical functions have been identified with identical reference numbers throughout the various views illustrated in the accompanying figures of the drawings. Referring now to Figure 1, a wagon-mounted brake assembly, designated in general 10, is shown for a rail car (not shown). This brake assembly 10 comprises beams brake, generally designated 2 and 3, which are substantially identical, ebrake beam including a compression member 4, a tension member 6 and a fixing member 8. The opposite ends of the compression member 4 and the tension member 6 can be connected together permanently, preferably by welding along an outer segment 4a-6a, 4b-6b at the opposite ends of the compression member 4 and tension member 6. At an intermediate location between their opposite ends, the compression member 4 and the tension member 6, of the respective brake beams 2 and 3, are sufficiently separated to allow connection of the fixing member 8 therebetween. Mounted on the end, outer, respective segments 4a-6a and 4b-6b of the brake beams 2 and 3 are the brake heads 12. A pair of force transfer levers 14 and 16 are pivotally connected by pins 18 to the fixing member (not shown) of the respective brake 2 and 3. Eend 24 and 26 of the respective force transfer levers 14 and 16 are interconnected via the force transmission member 28, which may be in the form of an automatic slack adjuster. The opposite end 36 of the force transfer lever 16 is connected to the pressure head 19 of the mounting 20 of the brake cylinder via a force transmission member or return push rod assembly 32. When a brake application is made, the pressurization of the brake cylinder assembly 20 results in the piston drive of the brake cylinder located in the brake cylinder assembly 20. This actuation of the piston causes a spring, also located in the brake cylinder assembly, to be compressed, resulting in the movement of a push rod, which is attd to the force transfer lever 14, in a direction to effect the rotation in the counterclockwise direction of the force transfer lever 14. The force transfer lever 14, in turn, drives the slack adjuster assembly 28 to perform counterclockwise rotation in the force transfer lever 16 and the consequent drive of the push rod assembly 32. return. The force transfer levers 14 and 16, together with the clearance adjustment assembly 28, the return push rod assembly 32 and the brake cylinder assembly 20 comprise a drive linkage of the brake beams interconnecting the beams 2 and 3 of the brake via the pivot pins 18 and in this way the forces required brake actuation act effectively along these pins 18. The resultant of these forces are shown in X. Since the length of the slack adjuster assembly 28 is increased by the actuation of the cylinder piston rod 37 of brake, it follows that the brake beams 2 and 3 are moved apart by the brake beam joint until the coupling of the brake shoes with the surface of the tread is present, as shown in 29, of the vehicle wheels 31. During a parking situation when railway cars separate from the train and park in a siding or yard, the pneumatic brake system, as described above, can not be used any longer. In this way, in order to apply the brake as a precaution against the unwanted and unexpected movement of the wagons, a brake mechanism that is mounted on each wagon can be employed. With reference to Figure 3, a commonly used hand brake mechanism, designated generally as 40, is shown in a truck mounted brake assembly. The brake mechanism 40 has housing, generally designated 42, which comprises a rear plate or wall 44, mountable in a rail car, and a cover 46. The cover 4 6 is secured to the rear wall 44.

A chain 48, for the application or release of the brakes, is connected, as is conventional, to the brake rig via a hand brake lever 50, chain 48 which is attached to and wound on a winding drum 52. The hand brake lever 50 in turn is connected to the transfer lever of the air cylinder or force transfer lever 14. In order to apply the brakes, a handwheel 54 is rotated in a clockwise direction to wind the chain 48 around the winding drum 52 and to cause the hand brake lever 50 to pull. in a direction away from the brake rig 10. This causes the force transfer lever 14 to rotate in a counterclockwise direction resulting in the push rod of the piston being pulled in an outward direction and the force required to be applied to the assembly. slack adjuster. This force is similar to the force applied by the brake cylinder piston, not shown, of the air cylinder assembly 20 when it is pressurized. The present invention will replace this manual brake lever / chain / handwheel system, manually operated with a spring applied / air released parking brake assembly. The parking brake assembly applied with spring / released with air of the present invention has the additional bonus that is automatically activated when the wagon has been removed from the train and the pneumatic brake system used to activate the truck-mounted brake system, discussed above, has been disconnected. Once the wagon has been reconnected to the train and the pneumatic brake system is active again, the spring applied parking brake assembly of the invention is released. Referring again to Figure 1, the spring-applied parking brake assembly 60 is preferably mounted to the side of the brake cylinder 20. The exemplary mounting locations for the parking brake assembly may be the compression member or the brake beam of the truck-mounted brake system, however, any location that can sufficiently support the brake assembly may be used. and ensure that activation of the spring applied parking brake assembly results in a counterclockwise rotation of the force transfer lever. This assembly can be achieved by means of a bolt / nut arrangement 66, as shown by Figure 4, for joining and / or coupling the parking brake assembly with the vehicle brake system. The transfer lever force includes an extension force 64 and the piston rod 62 of the spring applied brake assembly 60 is attached to this extension piece. This connection is achieved by a well-known means such as, for example, a clamp 63. The activation of the parking brake assembly results in an outward movement of the piston rod 62 which in turn causes an outward movement of the part. of extension 64 and rotation in the counterclockwise direction of the force transfer lever 14. Figure 4 shows a sectional view of the spring applied parking brake assembly 60 of Figure 1 wherein the spring member is compressed and the piston assembly is in the released position. The parking brake assembly 60 comprises the liner 67 enclosing a piston assembly, designated generally 70, which is mounted for longitudinal movement within the liner 67. The piston assembly 70 includes a piston 76, a diagram 78, and a piston rod 62 secured to a first end 79 of the piston assembly 70. This piston rod is capable of extending through an opening in a first end 81 of the liner. Dock members 68 are placed within the liner 67 and confined between an inner surface 71 of a second end 72 of the liner 67 and a second end 74 of the piston assembly 70. This member 68 of the dock is able to exert a force against the piston assembly 70 on the release of the spring member 68 to cause longitudinal movement of the piston assembly 70. The rod 62 of the piston is contained within a recess 65 tube and the hollow tube is associated with the piston 76 via a medium 75 binding and also sealed to the diaphragm 78 with an O-ring 77. The diaphragm 78 and piston 76 they are sealed against the inner wall of the liner 67 by means of an O-ring 82. The piston rod 62 includes a joining means, such as a bracket 63, for the connection of the rod 62 to the extension piece 64 of the force transfer lever 14. In the removal of the car of the railway vehicle and therefore the air brake system of the vehicle, longitudinal movement of the piston assembly 70 in a first direction B so -automatic is presented, as the spring member 68 extends to its natural position This longitudinal outward movement causes the force transfer lever 14 to rotate in a counterclockwise direction and apply the brakes to the car. This system is capable of the parking brake assembly 60 always being in an activated position when the wagon is removed from the train and disconnected accordingly from the pneumatic brake system. Since the assembly 60 of the parking brake of the invention is always in the activated position when the train is disconnected from the pneumatic brake system of the vehicle, the undesired and / or dangerous movement of the parked car due to operator error is prevented. Once the wagon has been hooked to the train and the pneumatic brake system is connected thereto, the parking brake assembly 60 is automatically deactivated. This deactivation is caused by the movement of the piston assembly 70 which causes the piston rod 62 attached to the extension piece 64 of the force transfer lever to move in a second direction C resulting in a compression of the member 68 of the piston. Dock and a release of the brakes. This compression of the spring member 68 is caused by the application of air from the pneumatic train brake system through an air inlet 69 in the liner which, in turn, pressurizes the diaphragm / piston 78, 79, causing this diaphragm / piston, which is attached to the rod 62 of the piston, a distance to move and in a C direction to determine the compression member 68 spring and the rotation in the direction of clockwise lever 14 of force transfer. As illustrated in Figures 4 and 5, an arrangement or system, designated in general as 80, it is also provided in the parking brake assembly 60 to obtain the parking brake in the released position during the installation of the parking brake assembly 60 in the vehicle brake system. This retaining arrangement can also be used if it is desired at any other time to retain the parking brake in the position released after installation in the car and in the removal of the wagon from the pneumatic brake system of the railway vehicle. The retaining arrangement includes a cylindrical member 82, such as a hollow tube or rod, which is mounted for longitudinal movement within the liner 67. The cylindrical member 82 is associated with the piston assembly 70, such as a joining means 86. , in a first end 84 such that the movement of the cylindrical member 82 causes the piston 76, as well as the spring member 68, to move with respect to each other. An opening is provided within a lining end surface 67 and a second end 88 of the cylindrical member 82 extends through this opening. The movement of the cylindrical member 82 in a direction to cause the second end 88 of the cylindrical member 82 to extend through the opening of the liner causes the piston 76 of the piston assembly 70 to apply a compressive force to the spring member 68. Compression of spring member 68 results the movement of the piston rod 62 of the piston assembly 70 in a released position. A retaining means 92 is then provided to retain this cylindrical member 82 in place so that the spring member 68 is compressed and the piston assembly 70 remains in the released position. Having the parking brake assembly 70, specifically the piston rod 62, in the released position is desirable during the installation of the parking brake assembly 60 in the vehicle brake system. The retention system 92 for the cylindrical member 82 may be in the shape of a spike extending through a hole 91 in the cylindrical member 82, as shown for example in Figure 5. Also, a stop member 94 it may be provided in the cylindrical member 82 to prevent the cylindrical member from extending too much and / or from completely pulling the liner 67. The present invention provides an ergonomic alternative to handbrakes, activated with a handwheel, commonly used. of the prior art. Additionally, because the spring applied parking brake assembly of the present invention is automatically activated in the removal of the wagon from the vehicle's air brake system, the possibility of the initiated movement of a parked car. In this way, the present invention has been described in complete, clear, concise and exact terms to allow any person skilled in the art to which it corresponds to make and use it. It will be understood that the variations, modifications, equivalents and substitutions for the components of the specifically described embodiments of the invention can be made by those skilled in the art without departing from the spirit and scope of the invention as set forth in the claims.

Claims (18)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, the content of the following CLAIMS is claimed as property: 1. A brake assembly applied with a spring for a railway vehicle brake system, the rail vehicle brake system including a force transfer lever and at least one force transmission member for initiating a brake application, the spring applied brake assembly comprises: (a) a liner engageable with the brake system; brake of the railway vehicle; (b) a piston assembly positioned inside and mounted for longitudinal movement within the liner; (c) a piston rod secured to a first end of the piston assembly and capable of extending through an opening in a first end of the liner; (d) a spring member positioned in the liner and confined between an inner surface and a second end of the liner and a second end of the piston assembly, the spring member that is capable of exerting a force against the piston assembly in the release of the spring member causing the longitudinal movement of the piston assembly inside the liner; and (e) a joining means for associating the piston rod with the force transfer lever such that the longitudinal movement of the piston assembly causes the force transfer lever to rotate and apply a force to at least one transfer member of force to start a brake application. A spring applied brake assembly according to claim 1, wherein the liner includes an air inlet to allow air to be applied within the liner to cause the piston assembly to move in a direction to compress the bladder member. Dock and disable the piston assembly. 3. A spring applied brake assembly according to claim 1, wherein the force transfer lever includes an extension piece which is attached thereto and the attachment means is associated with the extension piece. A spring applied brake assembly according to claim 1, wherein the vehicle brake system includes at least one of a brake beam and a compression member and the liner includes a joining means for mounting the brake assembly to at least one of a brake beam and a compression member. 5. A brake assembly applied with spring according to claim 1, wherein the piston mounting means further includes a piston and a diaphragm. A spring applied brake assembly according to claim 2, wherein the piston mounting means includes a piston / diaphragm arrangement and a sealing means is placed between the liner and the piston / diaphragm arrangement to prevent leakage of air. A spring applied brake assembly according to claim 5, wherein the sealing means is an O-ring. A spring applied brake assembly according to claim 5, wherein the first end of the spring member is placed adjacent to the inner end surface of the liner and the second end of spring member is positioned adjacent to the piston of the piston assembly. 9. An arrangement for installing a spring loaded brake assembly within a rail vehicle brake system, the spring applied brake assembly including a liner, a piston assembly positioned within the liner, and a confined spring member between an inner end surface of the liner and an end surface of the piston assembly, the piston assembly which is mounted for longitudinal movement within the liner in accordance with the extension and compression of the Dock, the arrangement for installing the spring applied brake assembly comprises: (a) a cylindrical member mounted for longitudinal movement within the liner, the cylindrical member having a first end and a second end; (i) the first end of the cylindrical member extending through an opening in the liner; (ii) the second end of the cylindrical member that is associated with the piston assembly and the spring member such that the longitudinal movement of the cylindrical member in a first direction causes the piston assembly to move in the first direction to compress the member of dock; and (b) a retention means positioned in and connectable with the first end of the cylindrical member to retain the cylindrical member such that the spring member is held compressed during the installation of the spring applied brake assembly within the vehicle brake system railway. An arrangement for installing a spring applied brake assembly within a rail vehicle brake system according to claim 9, wherein the first end of the cylindrical member includes a hole extending through the sidewalls thereof and the means of retention it includes a spike for extending through the bore of the cylindrical member. An arrangement for installing a spring applied brake assembly within a rail vehicle brake system according to claim 9, wherein the cylindrical member includes a stop means mounted on the side walls thereof to prevent movement of the member cylindrical greater at a predetermined distance through the liner opening. 12. A spring loaded brake assembly for a rail vehicle brake system, the rail vehicle brake system including a force transfer lever and at least one force transmission member to initiate a brake application, the Brake assembly applied with spring comprises: (a) a lining engageable with the railway vehicle brake system; (b) a piston assembly positioned inside and mounted for longitudinal movement within the liner; (c) a piston edge secured to a first end of the piston assembly and capable of extending through an opening in a first end of the liner; (d) a spring member placed in the liner and confined between an inner surface and a second end of the liner and a second end of the piston assembly, the spring member being able to exert a force against the piston assembly on the release of the spring member causing longitudinal movement of the piston assembly between the liner; and (e) a joining means for associating the piston rod with the force transfer lever such that the longitudinal movement of the piston assembly causes the force transfer lever to rotate and apply a force to at least one transfer member of force to initiate a brake application; and (f) an arrangement for installing the brake assembly applied with spring within the rail vehicle brake system, the arrangement for installing the spring applied brake assembly includes: (i) a cylindrical member mounted for longitudinal movement within the liner, the cylindrical member having a first end and a second end, the first end of the cylindrical member extending through an opening in the liner and the second end of the cylindrical member that is associated with the piston assembly and the member of spring such that the longitudinal movement of the cylindrical member in a first direction causes the piston assembly to move in the first direction to compress the spring member; Y (ii) a retaining means positioned and unible with the first end of the cylindrical member for retaining the cylindrical member in place such that the spring member is kept compressed during the installation of the spring applied brake assembly within the brake system of railway vehicle. 13. A spring applied brake assembly according to claim 12, wherein the liner includes an air inlet to allow air to be applied within the liner to cause the piston assembly to move in a direction to compress the bladder member. Dock and release the brake assembly. A spring applied brake assembly according to claim 12, wherein the force transfer lever includes an extension piece attached thereto and the piston rod is connected to the extension piece. A spring applied brake assembly according to claim 12, wherein the piston mounting means includes a piston, a diaphragm, and a piston rod. 16. A spring applied brake assembly according to claim 15, wherein the first end of the spring member is positioned adjacent to the inner end surface of the shell and the second end of the spring member is positioned adjacent the piston of the shell assembly. piston. 17. A brake assembly applied with spring according to claim 12, wherein the first end of the cylindrical member includes an orifice extending therethrough and the rotation means includes a shank for extending through the bore of the cylindrical member. A spring applied brake assembly according to claim 12, wherein the cylindrical member includes a stop means for preventing movement of the major member at a predetermined distance through the opening of the liner.