Patent Application
20210348340
The present disclosure relates generally to anchoring mechanisms used in track rail, and more particularly to a spring anchor assembly including a spring anchor and an insulator fitted upon the spring anchor.
Rail equipment is used across the world for transportation of persons and all manner of goods and equipment. Rail lines for freight or passenger service are formed by parallel track rails supported upon a substrate or “ballast,” typically by fixation to ties. Depending upon the design of the rail line and the type of substrate and supporting materials, including concrete ties versus wooden ties, use of gravel, concrete or other materials, a variety of different mechanisms are used for positioning, supporting, and fastening track rails and managing loads and vibrations transmitted between rail equipment and the underlying substrate.
Rail fastening and fixation systems range from simple plates that attach rails to wooden ties by way of spikes, to highly engineered direct fixation fasteners formed from an assembly of metallic and non-metallic components. Direct fixation fasteners are typically used to clamp a section of track rail to underlying concrete such as a concrete tie. The direct fixation fasteners will typically cushion the track rail and limit lateral movement, often providing for some degree of lateral adjustability as rail gauge changes based upon material wear over time.
Other rail fastening and anchoring components are often used to prevent shifting or migration of track rail in a fore and aft direction, and can include devices known as spring anchors that are clamped to a section of track rail upon a forward side and a back side of a concrete tie, for example. One known spring anchor design is set forth in U.S. Pat. No. 7,744,009 to Reed et al. Reed provides an isolator adapted for use with a rail anchor in applications where rail is installed on concrete ties. The isolator apparently protects the concrete tie from contact with the rail anchor caused by longitudinal movement of the rail. While the design set forth in Reed et al. may address certain concerns, there is always room for improvements and alternative strategies in the field.
In one aspect, a spring anchor assembly for fastening track rail upon a tie includes a spring anchor having an elongate spring body with a hook end, a tail end, and a middle section. The spring anchor assembly also includes an insulator fitted upon the spring anchor and including an upper insulator side exposed between the hook end and the tail end, a lower insulator side, and a first outer insulator wall and a second outer insulator wall extending downward from the upper insulator side. The first outer insulator wall and the second outer insulator wall each include an upper peripheral edge extending along the upper insulator side, and a lower peripheral edge extending curvilinearly along the lower insulator side. The insulator further includes a plurality of rib walls extending fore and aft from the first outer insulator wall to the second outer insulator wall, and downward from the upper insulator side to termination locations spaced upward from the lower peripheral edges. The first outer insulator wall and the second outer insulator wall form a first downward depending wall section and a second downward depending wall section extending, respectively, from the termination locations to the lower peripheral edges. A channel is formed fore and aft between the first downward depending wall section and the second downward depending wall section. The middle section of the elongate spring body is received in the channel and contacted by the plurality of rib walls at each of the termination locations.
In another aspect, a spring anchor insulator includes an insulator body having an upper insulator side with an upper insulator surface extending between a first lateral insulator end and a second lateral insulator end, and a lower insulator side. The insulator body further includes a first outer insulator wall and a second outer insulator wall each including an upper peripheral edge extending linearly along the upper insulator side, and a lower peripheral edge extending curvilinearly along the lower insulator side. The insulator body further includes a plurality of rib walls extending fore and aft from the first insulator wall to the second insulator wall, and downward from the upper insulator side to termination locations spaced upward from the lower peripheral edges. The first outer insulator wall and the second outer insulator wall form a first downward depending wall section and a second downward depending wall section extending from the termination locations to the respective lower peripheral edges. A channel is formed fore and aft between the first downward depending wall section and the second downward depending wall section and has a curvilinear shape between the first lateral insulator end and the second lateral insulator end to receive a curved middle section of a spring anchor.
In still another aspect, a spring anchor insulator includes an insulator body having an upper insulator side with an upper insulator surface extending between a first lateral insulator end and a second lateral insulator end, and a lower insulator side. The insulator body further includes a first outer insulator wall and a second outer insulator wall spaced apart in a fore and aft direction. The first outer insulator wall and the second outer insulator wall each include a planar outer face, an upper peripheral edge extending along the upper insulator side, and a lower peripheral edge extending along the lower insulator side. The insulator body further includes a plurality of anchor contact surfaces arranged in a curvilinear pattern between the first lateral insulator end and the second lateral insulator end, and spaced upwardly from the lower peripheral edges so as to form a channel between the first outer insulator wall and the second outer insulator wall, for receiving a curved middle section of a spring anchor.
Referring to
Referring also now to
Referring now also to
Insulator 28 is fitted upon spring anchor 26 as discussed above, and includes an upper insulator side 40 exposed between hook end 32 and tail end 34, and faces a generally upward direction. Insulator 28 includes one-piece insulator body 29 as noted above. It should be understood that insulator 28 and insulator body 29 are terms used interchangeably herein, and thus a reference to insulator 28 can be understood as a reference to insulator body 29, and vice versa. Insulator 28 further includes a lower insulator side 42, and a first outer insulator wall 44 and a second outer insulator wall 46 extending downward from upper insulator side 40. First outer insulator wall 44 and second outer insulator wall 46 each include an upper peripheral edge 48 and 50, respectively, extending linearly along upper insulator side 40. Each of first outer insulator wall 44 and second outer insulator wall 46 further includes a lower peripheral edge 52 and 54, respectively, extending curvilinearly along lower insulator side 42.
Referring now also to
Insulator 28 may further include a plurality of rib walls 56 extending fore and aft from first outer insulator wall 44 to second outer insulator wall 46. Rib walls 56 may form, together with first outer insulator wall 44 and second outer insulator wall 46, drain channels 86 opening at upper insulator side 40. Drain channels 86 are elongate fore and aft and may number from 5 to 10, for instance, with a number of drain channels 86 being 7 in the illustrated embodiment. Insulator 28 includes an upper insulator surface 74 that extends, when insulator 28 is fitted upon spring anchor 26, from hook slot 68 to catch slot 72, and may be planar. Drain channels 86 form openings in upper insulator surface 74.
Rib walls 56 further extend downward from upper insulator side 40 to termination locations 58 spaced upward from lower peripheral edges 52 and 54. It can be seen, as in the sectioned view of
It can also be noted from
Returning to the drawings generally, first outer insulator wall 44 and second outer insulator wall 46 form a first downward depending wall section 62 and a second downward depending wall section 64 extending, respectively, from the termination locations 58 of rib walls 56 to lower peripheral edges 52 and 54. A channel 66 is formed fore and aft between first downward depending wall section 62 and second downward depending wall section 64. Drain channels 56 open at upper insulator side 40, and to channel 66. Middle section 36, including belly section 76, is received in channel 66 and contacted by rib walls 56 and anchor contact surfaces 60 at each of termination locations 58. It will thus be appreciated that downward depending wall sections 62 and 64 can be understood to flank fore and aft sides of elongate spring body 30. It will be recalled that spring anchor assembly 24 is structured to anchor track rail 10 against displacement in a longitudinal, fore and aft direction. Accordingly, downward depending wall sections 62 and 64, depending upon which side is adjacent to a tie, can provide electrical and physical insulation between spring anchor 26 and tie 12, and thus between track rail 10 and the underlying substrate as further discussed herein. As noted above, termination locations 58 define a curve that is parallel to lower peripheral edges 52 and 54. Accordingly, channel 66 is curved, and may have a generally uniform depth in vertical directions, and a generally uniform width fore and aft between downward depending wall sections 62 and 64. Channel 66 is also typically sized such that curved belly section 76 is not quite completely obscured. In other words, spring anchor 26 is not entirely hidden within channel 66 as can be seen from the drawings. It can also be noted from the Figures that insulator 28 includes wall protrusions 82 that form first lateral insulator end 31. Wall protrusions 82 may be structured as thin, generally rectangular extensions of first outer insulator wall 44 and second outer insulator wall 46 that flank elongate spring body 30 along a transition from middle section 36 to hook end 32 when insulator 28 is installed for service. Channel 66 is generally open at each of first lateral insulator end 31 and second lateral insulator end 33. Second lateral insulator end 33 may be formed by wall sections 84 profiled continuously with lower peripheral edges 52 and 54, and with upper insulator side 40.
Referring to the drawings generally, as noted above insulator 28 can provide physical as well as electrical insulation between spring anchor 26 and an underlying substrate. Spring anchor 26 will typically have metal to metal contact with track rail 10. Most modern track rails are used to conduct electrical signals in support of rail operations, and where there is direct electrical contact by way of a conductive path from the track rail to the ballast, electrical signals in the track rail can be partially diverted to the ground by way of spring anchors if not insulated. This is particularly the case where ties are made of concrete. Insulating the spring anchor from the tie using non-conductive material as discussed herein can mitigate the loss of electrical signals previously observed.
The present disclosure provides not only an insulator that can prevent electrical signal loss in the manner described, but also has various advantages with respect to installation and performance in service. Insulator 28 is symmetric about a middle, laterally extending vertical plane, with body walls having planar outer surfaces 45 and 47 connected by rib walls 56. As also discussed above, the fore and aft sides of insulator 28 formed by outer faces 45 and 47 can have a vertical draft that is similar to a draft on a concrete tie, providing a relatively large bearing surface with a tie and extending the service life of insulator 28. As insulator 28 does not extend spatially beyond spring anchor 26 in a left to right or lateral aspect, or in a vertical aspect below spring anchor 26, the use of mechanized spring anchor installation tools purpose-built for a given spring anchor spatial envelope can be expected to perform without damaging insulator 28. When spring anchor assemblies according to the present disclosure are removed, a technician or a tool may be used to hammer downward upon an upper tip of tail 26. The configuration and fitted, asymmetric shape of insulator 28 upon spring anchor 26 is also contemplated to enable removal of spring anchor assemblies without damaging the insulator. Embodiments are contemplated where spring anchor assemblies are provided for field installation already assembled, where spring anchor and insulator components are coupled together in the field, as well as even potentially retrofit applications where an existing spring anchor can be uninstalled, equipped with an insulator according to the present disclosure, and then reinstalled for service.
The present description is for illustrative purposes only, and should not be construed to narrow the breadth of the present disclosure in any way. Thus, those skilled in the art will appreciate that various modifications might be made to the presently disclosed embodiments without departing from the kill and fair scope and spirit of the present disclosure. Other aspects, features and advantages will be apparent upon an examination of the attached drawings and appended claims. As used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more.” Where only one item is intended, the term “one” or similar language is used. Also, as used herein, the terms “has,” “have,” “having,” or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.
