The present disclosure generally relates to retarder systems for railway cars, and more particularly to a universal system for railway cars incorporating springs, pneumatic and/or hydraulic cylinders for tangent, skate, and other retarders.
The Background and Summary are provided to introduce a foundation and selection of concepts that are further described below in the Detailed Description. The Background and Summary are not intended to identify key or essential features of the potentially claimed subject matter, nor are they intended to be used as an aid in limiting the scope of the potentially claimed subject matter.
The following U.S. Patents and Patent Applications are incorporated herein by reference:
U.S. Pat. No. 4,393,960 discloses a brake shoe structure which includes a series of alternating long brake shoes and short brake shoes mountable on adjacent brake beams in a railroad car retarder. The length of the long brake shoe is such that the long brake shoe symmetrically straddles two adjacent brake beams. The length of the short brake shoe is such that the shoe occupies the spacing on the brake beams between two long brake shoes. The long brake shoes are affixable to each of the brake beams at at least two points. The brake shoes contain a plurality of slanting slots in their braking surfaces for interrupting harmonics procuring screeching noises during retardation. The brake shoes may be formed of steel or heat treatable ductile iron.
U.S. Pat. No. 7,306,077 discloses a fail-safe skate retarder that applies a braking force proportional to the weight of a rail car entering the retarder. Each segment of the retarder includes a lever mechanism with a pair of levers rotatably joined under the running rail. Each lever holds a braking rail for engaging a wheel of the car. The retarder is normally in a lower, fail-safe position with the brake rails closer together than the width of the wheel. When the car enters the retarder, the wheel forces the brake rails apart into a braking position, and the middle of the lever mechanism rises to lift the running rail and car. A hydraulic power unit and cylinder is activated to raise the middle of the lever mechanism even further to a release position so that the brake rails are spread apart more than the width of the wheel.
U.S. Pat. No. 7,392,887 discloses a low-maintenance bladder actuator for a low-profile railroad retarder. The actuator has an internal guide mechanism and internal limit stops. The guide mechanism has a concentric, telescoping guide rod and guide sleeve that are removably bolted to upper and lower plates. An integral cast head forms the upper plate and a stop sleeve that absorbs the cyclical 20,000 pound loads of the actuator. This enables the guide rod to remain concentrically aligned. The guide mechanism has sufficient stroke length (SL) and includes a long internal bushing with a low wear rate. The stop sleeve engages the lower plate to form the lower limit stop. The stop sleeve includes an inwardly extending flange that engages an outwardly extending flange of the guide sleeve to form an upper limit stop. The stop sleeve and guide sleeve form a cam lock connection for easy assembly.
U.S. Pat. No. 8,413,770 discloses systems and methods for retarding the speed of a railcar are provided. A supply of pressurized hydraulic fluid is provided to a piston cylinder to actuate the cylinder and thereby move a brake into a closed position in which the brake will apply a predetermined braking pressure to a wheel of the railcar. An accumulator accumulates fluid from the circuit when the wheel forces the brake out of the closed position and supplies accumulated fluid back to the circuit as the brake moves back into the closed position to thereby maintain a substantially constant braking pressure on the wheel as it moves through the retarder.
U.S. Pat. No. 8,899,385 discloses systems for retarding the speed of a railcar comprise: a brake; a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on a wheel of the railcar and an open position in which the brake does not apply braking pressure on the wheel of the rail car; a hydraulic circuit comprising a first manifold and a second manifold; a pump configured to pump hydraulic fluid into at least one of the first manifold and the second manifold; and a logic element controlling pressure of the fluid in the first manifold such that when the wheel enters the brake and forces the brake towards the open position. The logic element reacts to maintain a selected pressure in the first manifold, thus causing a selected braking pressure to be applied by the brake on the wheel of the railcar.
U.S. Pat. No. 9,862,368 discloses a system for retarding the speed of a railcar comprises a brake; a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on the wheel of a railcar, and an open position in which the brake does not apply braking pressure on the wheel of the railcar; a hydraulic circuit provided with a pump arrangement for supplying hydraulic fluid to the hydraulic actuator; and a control circuit coupled to the hydraulic circuit for controlling the flow of hydraulic fluid to move the brake between the closed and open positions.
U.S. Patent Application Publication No. 2008/0237511 discloses an electro-pneumatic retarder control (EPRC) valve for a pneumatic retarder that controls the speed of railroad cars in a marshaling yard. The EPRC valve has a housing that generally encloses and protects its various components. The housing has a lid that can be opened to gain access to a control panel mounted on an interior door. The control panel includes a display, keyboard and programmable logic controller or PLC module that can be adjusted to set the desired pressure levels of the retarder. The EPRC valve has a modular pressure control assembly that includes an intake and exhaust manifold, a retarder supply and return manifold and several interchangeable control lines formed by like-shaped control valves and components. A pilot air control assembly enables the PLC module to selectively open and close the control valves and lines to deliver or release pressurized air to the retarder.
U.S. Patent Application Publication No. 2010/0252372 discloses several embodiments of a system for connecting brake shoes to brake beams in a railroad car retarder all provide enhanced connecting joint tightness that reduces premature connecting joint loosening, reduces maintenance, and reduces failure of connecting bolts or equivalent connecting pins.
One embodiment of the present disclosure generally relates to a universal retarder system for slowing a railcar on rails. The system includes a lever arm configured to be pivotable within a vertical plane, where the lever arm is configured to support a brake shoe. An engagement device is coupled to the lever arm and configured to pivot the brake shoe towards one of the rails. A disengagement device is coupled to the lever arm and configured to pivot the brake shoe away from the one of the rails. The lever arm, engagement device, and disengagement device are each positioned between the rails. Pivoting the brake shoe towards the one of the rails is configured to force the brake shoe into engagement with the railcar to slow the railcar.
Another embodiment generally relates to a universal retarder system for slowing a railcar on rails. The system includes a lever arm configured to be pivotable about a horizontal axis parallel to the rails, where the lever arm is configured to support a brake shoe, the lever arm has a proximal end force mount configured to receive a proximal force to pivot the lever arm, and the lever arm has a distal end force mount configured to receive a distal force to pivot the lever arm. A proximal support and a distal support are each configured span between adjacent ties supporting the rails. The proximal support is configured to support one of an engagement device and a disengagement device for applying the proximal force on the lever arm, and the distal support is configured to support an other of the engagement device and the disengagement device for applying the distal force on the lever arm. The lever arm, engagement device, and disengagement device are each positioned between the rails. The one of the proximal force and the distal force applied by the engagement device causes the lever arm to pivot to thereby force the brake shoe into engagement with the railcar to slow the railcar.
Another embodiment generally relates to a universal retarder system for slowing a railcar on rails. The system includes a lever arm configured to be pivotable within a vertical plane, where the lever arm is configured to support a brake shoe. An engagement device is coupled to the lever arm and configured to pivot the brake shoe towards one of the rails. A disengagement device is coupled to the lever arm and configured to pivot the brake shoe away from the one of the rails. The lever arm, engagement device, and disengagement device are each positioned between the rails. The lever arm is pivotable about an axis that is closer than both of the engagement device and the disengagement device to the one of the rails, and the lever arm has a length greater than half of a distance between the rails. Pivoting the brake shoe towards the one of the rails is configured to force the brake shoe into engagement with the railcar to slow the railcar.
The drawings illustrate embodiments for carrying out the disclosure. The same numbers are used throughout the drawings to reference like features and like components. In the drawings:
This written description uses examples to disclose embodiments of the present application and also to enable any person skilled in the art to practice or make and use the same. The patentable scope of the invention is defined by the potential claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
The present inventors have identified several issues with retarder systems presently known in the art for slowing or stopping a railcar on a railroad track, particularly within the context of a rail yard. First, it is often desirable to place tracks as close together as possible, minimizing the amount of space required to provide many separate lines within a yard. However, it is also desirable to provide sufficient clearance between tracks such that personnel and equipment can navigate between adjacent tracks. In this regard, the present inventors have identified that it would be beneficial for the equipment associated with retarder systems to be located within the rails of a given track, rather than including components that sit outside of the rails as is customary with retarder systems known in the art. This maximizes the effective (usable) space between tracks, while also reducing tripping hazards and the potential for damaging retarders and other equipment.
While other retarder systems have been developed that are mostly or entirely contained within the rails of a track, these systems are overly complex, difficult to service, overly expensive, and/or lack the performance and reliability desired. Exemplary embodiments of other systems placing components primarily between the rails of a track include those described in U.S. Pat. No. 6,829,998 and U.S. Patent Application Publication No. 2013/0068124. These systems each incorporate components that rotate about a vertical axis to apply or retract braking elements to slow or stop a railcar. While these systems are contained primarily within the rails of the track, each nonetheless suffers from the other disadvantages previously described, including complexity, cost, and maintenance time.
The present inventors have also identified further issues with systems presently known in the art, including the systems described in U.S. Pat. No. 6,829,998 and U.S. Patent Application Publication No. 2013/0068124. In particular, these systems provide a conduction path between the individual rails of a track system. Many rail yards incorporate devices and equipment that require the individual rails within a track to be electrically isolated. For example, certain systems for detecting the presence of a car on a track function by providing a low voltage on one individual rail, then detecting the presence of the voltage on the opposite rail. When a car is present, the car completes the circuit such that the low voltage is conducted between the individual rails, thereby allowing detection of the presence of the railcar on that segment of the track.
However, when retarder systems create a shunt between the individual rails, irrespective of the presence of a railcar thereon, these car detection systems are rendered inoperable. This places a yard manager in the difficult situation of either selecting only among retarder systems that allow existing railcar detection systems to function, or selecting a retarder system knowing that it will render the railcar detection system inoperable. Since the detection of railcars on a given segment of track is critical for managing the yard, this obstacle often precludes the availability of alternative retarder systems for upgrading or replacing as existing retarder systems fail or are replaced.
One way that retarder systems known in the art end up shunting the individual rails is through the use of steel ties or other steel reinforcement structures that are tied between the individual rails. Likewise, steel within other components of the retarder system that at some point contact both individual rails (whether directly or indirectly) also creates a conduction pathway between the individual rails, rendering the railcar detection systems inoperable as described above.
As best shown in the bottom view of
The present inventors have identified that by providing an offset configuration of the lever arms 80, each lever arm 80 can be extended in length L (
As shown in
The proximal support 60 and distal support 70 are directly or indirectly mounted to the ties 20 via mounting hardware 62 and mounting hardware 72, respectively (
The chairs 40 further include tie bolt washers 47 and rail clips 49, as well as steel filler plates 26 (
In this manner, the lever arm 80 is pivotable about the pivot axle 50 relative to the chair 40 to selectively release and engage braking of the universal retarder system 1. As shown in
The pivot axle 50 is further received within a pivot axle opening 86 within a lever arm 80, particularly located near the proximal end 82. In certain embodiments, a bushing 94 is provided to electrically isolate the lever arm 80 from the pivot axle 50. A rotation face 83 at the proximal end 82 is configured to face the chair 40 on each side of the lever arm 80 (in some cases prevented from making contact by the bushing 94 as discussed). In this manner, mechanical advantage is most exploited because forces are applied towards the distal end 84 of the lever arm 80. The presently disclosed universal retarder system 1 permits the use of longer lever arms 80 than systems presently known in the art, particularly among systems retained between the running rails 12.
As best shown in
The distal end force mount 100 of the present embodiment includes a lever mounting pin receiver 102 configured to receive a lever mounting pin 104 that also engages with the cylinder system 250. Similarly to the pivot axle 50 previously discussed, the lever mounting pin 104 further defines a lever mounting pin lock receiver 106 that receives a lever mounting pin lock 108 to retain the lever mounting pin 104 within the distal end force mount 100.
Referring to
As previously discussed,
In certain embodiments (shown in
The universal retarder system 1 permits multiple different biasing systems to be incorporated and mounted to the proximal support 60 for applying a force near the proximal end 82 of the lever arm 80, and likewise to the distal support 70 for applying a force near the distal end 84 of the lever arm 80 (see
In the tangent retarder system 32 shown in
As shown in
Referring to
The presently disclosed universal retarder system 1 also allows the incorporation of a hydraulic cylinder 252 in place of the pneumatic cylinder 251 for the cylinder system 250 previously discussed, as shown in
As shown in
In this embodiment, the proximal support 60 is no longer used, but a distal support 70 is used in the manner previously discussed. The skate retarder system 34 is configured as a fail-safe device, whereby the brake shoes 13 are normally engaged, for example by a passive spring system 200. Skate retarder devices 34 are frequently used in locations in which it is desirable for the railcars to be completely stopped, such as nearing the end of a line. In this manner, the function of the retarder is somewhat opposite of that previously discussed with the tangent retarder system 32, whereby engagement of a second force generator, such as the cylinder system 250, then causes disengagement of the lever arm 80 such that the brake shoes 13 are released.
Both the first force generator FG1 and second force generator FG2, namely the spring system 200 and cylinder system 250, are incorporated at the distal end 84 of the lever arm 80. In the embodiment shown, the spring 210 of the spring system 200 is positioned around the outer circumference of the cylinder system 250, which in the present example is a hydraulic cylinder 252. When hydraulic fluid is provided to the hydraulic cylinder 252 in the manner known in the art, entering the port 282 (
It should be recognized that the universal retarder system 1 presently disclosed alternatively permits the spring system 200 to be located closer to the proximal end 82 of the lever arm 80 as previously shown, specifically through the integration of a proximal support 60. However, the present inventors have identified that mechanical advantages can be gained by moving the spring system 200 further toward the distal end 84 of the lever arm 80. Likewise, the universal retarder system 1 presently disclosed permits alternative systems to be incorporated for opposing the spring system 200, including use of a pneumatic cylinder system 251 in place of the hydraulic cylinder system 252 shown in
In this manner, the universal retarder system 1 presently disclosed permits the same lever arm 80 and corresponding support and rotational elements to be used for a tangent retarder system 32, a skate retarder system 34, or other retarder systems presently known in art. Moreover, it permits the inclusion of spring systems 200, whether in tension as shown in
It is further known in the art that use of retarder devices causes wear on components over time. In order to accommodate for wear of the brake shoes 13, devices presently known in the art incorporate brake shoe shims 150 (presently disclosed embodiments of which are included in
Accordingly, the present inventors have developed the presently disclosed brake shoe shims 150, which are best shown in the embodiment of
Similarly, the present inventors have identified that the incorporation of the presently disclosed tab washer 160, such as that shown in
It should be recognized that while the brake shoe shims 150 and tab washer 160 were describe above principally in the context of tangent retarder systems 32 and skate retarder systems 34, the integration of these devices (together or individually) is applicable across all types of retarders. Moreover, the brake show shims 150 and tab washers 160 may be incorporated into prior art designs and retarder systems already deployed in the field to provide benefits according in the present disclosure.
Collectively, the universal retarder system 1 provides all of the necessary functions for slowing or stopping the railcar while positioning all relevant equipment between the running rails 12. Likewise, the common lever arm 80 of each type of system allows for a reduced inventory of parts between supporting tangent retarder systems 32, skate retarder systems 34, and other forms of retarders incorporating the presently disclosed systems. The present inventors have identified that this is advantageous in initial manufacturing of these devices, but also in maintaining the necessary supply of replacement parts in the field, as well as reducing the time and effort for service and reducing the risk of error in the process.
In the above description, certain terms have been used for brevity, clarity, and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. The different assemblies described herein may be used alone or in combination with other devices. It is to be expected that various equivalents, alternatives and modifications are possible within the scope of any appended claims.
The present application is based on and claims priority to U.S. Provisional Patent Application Ser. No. 62/684,289, filed Jun. 13, 2018, the disclosure of which is incorporated herein by reference.
Number | Name | Date | Kind |
---|---|---|---|
1868493 | Clausen | Jul 1932 | A |
1996139 | Bone | Apr 1935 | A |
2044762 | Bone | Jun 1936 | A |
2089823 | Bone | Aug 1937 | A |
2679809 | Beltman | Jun 1954 | A |
3163259 | Brown | Dec 1964 | A |
3209865 | Wynn | Oct 1965 | A |
3403752 | Garrett, Jr. et al. | Oct 1968 | A |
3819017 | Noble | Jun 1974 | A |
3827533 | Noble | Aug 1974 | A |
4030574 | Evans | Jun 1977 | A |
4393960 | Mazur et al. | Jul 1983 | A |
4867279 | Link | Sep 1989 | A |
5029675 | Zhukov | Jul 1991 | A |
6152042 | Barry et al. | Nov 2000 | A |
6829998 | Kickbush | Dec 2004 | B1 |
7306077 | Heyden et al. | Dec 2007 | B2 |
7392887 | Heyden et al. | Jul 2008 | B2 |
8413770 | Heyden et al. | Apr 2013 | B1 |
8899385 | Frailing et al. | Dec 2014 | B2 |
9862368 | Majeskie et al. | Jan 2018 | B2 |
20080237511 | Heyden et al. | Oct 2008 | A1 |
20100252372 | Heyden | Oct 2010 | A1 |
20130068124 | Kickbush | Mar 2013 | A1 |
Number | Date | Country | |
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20190382038 A1 | Dec 2019 | US |
Number | Date | Country | |
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62684289 | Jun 2018 | US |