Abstract:
A railroad switch indicator for visually signaling the position of a pair of railroad switchpoints independently of the mechanism for operating the switch. The indicator includes a sleeve with windows in which is reciprocated a slide with reflectors selected ones of which are visible through the windows of the sleeve for indicating safety conditions of the track. An arm with an upwardly extending finder is attached to a transverse bar that moves the switchpoints. The finger engages the slide through lever arms. When the finger moves with the switchpoints, the lever arms move the slide a distance greater than the distance moved by the finger thereby increasing the sensitivity of the railroad switch indicator to movement of the switchpoints. Movement of the slide by the finger is resisted by springs or counterweights which urge the slide into a mid or default position signaling caution.

Description:
This application claims priority from provisional application Ser. No. 61/228,300, filed Jul. 24, 2009, for Railroad Switch Indicator with Distance Amplifier. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a railroad switch indicator positioned between the stockrails for visually signaling the position of a pair of railroad switchpoints independently of the mechanism for operating the switch. The switch indicator includes a mechanism that amplifies a small movement of the switchpoints and that defaults to a position signaling caution. 
     2. Brief Description of the Prior Art 
     In order to optionally switch a railroad train operating on one track to a second track, it is typical to provide a switch with a pair of switchpoints which are selectively movable horizontally to deflect the train toward one or the other of the tracks. The switchpoints may be driven by a manual or electrical powered mechanism. A signal is usually associated with the mechanism for operating the switch to visually indicate how the switch is lined. If a train runs through the switch or if the switchpoints are moved by vibrations of a train rolling over the track, the switchpoints may be moved into a mid position which is not reflected by the signal associated with the mechanism for operating the switch. 
     When a train runs through a switch, a flange on the wheels picks open the switchpoints. Depending on how sharp the wheels are, the distance that the switchpoints move may be much less than an inch and yet a misalignment of as little as 0.25 inch may result in a disastrous derailment. Manual mechanisms commonly miss such a small movement and even sophisticated electrically powered switch mechanisms with sensors for open and closed switchpoints may give a false signal. 
     BRIEF SUMMARY OF THE INVENTION 
     In view of the above, it is an object of the present invention to provide a railroad switch indicator that operates independently of the mechanism for operating the switch. It is another object to provide a railroad switch indicator that signals movements of the switchpoints that may be missed by the mechanism for operating the switch and that defaults to a safe position signaling caution. It is also an object to provide a railroad switch indicator that does not depend on electricity and can be used with mechanically operated switches as well as electrically powered switches. Other objects and features of the invention will be in part apparent and in part pointed out hereinafter. 
     In accordance with the invention, a railroad switch indicator for use with a switch for switching a railroad train is provided. The switch includes a pair of stockrails and a pair of switchrails with the switchrails having first ends secured to a track bed and second ends terminating with switchpoints. The switchpoints are connected by a traverse bar for conjoint lateral movement of the switchpoints between switching and nonswitching positions. 
     The railroad switch indicator has a first bracket adapted to be attached to the track bed between the pair of switchpoints. The bracket supports a sleeve between and transverse to the stockrails and sleeve has front and rear walls with regularly formed spaced apart windows. Each of a first and second lever arm has a first end pivoted to the sleeve and a second end pivoted to a slide inside of the sleeve either directly or indirectly through a linkage including other lever arms pivoted to the sleeve. The slide has front and rear walls with reflectors, alternate ones forming a first and second set in different colors to indicate safety conditions of the track, the reflectors being visible through the windows of the sleeve. 
     A second bracket is adapted to be attached to the transverse bar connected to the switchpoints. The bracket supports a longitudinally extending arm with an upwardly extending finger which engages the lever arms for reciprocation of the slide within the sleeve conjointly with movement of the switchpoints by the transverse bar. The lever arms move the slide a greater distance than the distance moved by the finger thereby reducing the distance needed to signal a change in the switchpoints. 
     In use, the first set of reflectors are visible through the windows of the sleeve when the switchpoints are in a switching position, the second set of reflectors are visible through the windows of the sleeve when the switchpoints are in a nonswitching position and portions of the first and second set of reflectors are visible when the switchpoints are in a mid position indicating a dangerous condition. A biasing system works against the force of the finger urging the slide into the mid position. 
     The invention summarized above comprises the constructions hereinafter described, the scope of the invention being indicated by the subjoined claims. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       In the accompanying drawings, in which several of various possible embodiments of the invention are illustrated, corresponding reference characters refer to corresponding parts throughout the several views of the drawings in which: 
         FIG. 1  is a plan view of a railroad switch provided with a railroad switch indicator in accordance with the present invention; 
         FIG. 2A  is a side elevation of the railroad switch indicator signaling that a right switchpoint is in contact with a right stockrail; 
         FIG. 2B  is a side elevation of the railroad switch indicator signaling that a left switchpoint is in contact with a left stockrail; 
         FIG. 2C  is a side elevation of the railroad switch indicator signaling danger that the switchpoints are in a mid position; 
         FIG. 3  is perspective view of the railroad switch indicator; 
         FIG. 4  is an exploded perspective view of the railroad switch indicator; 
         FIG. 5A  is a side view in section taken along the plane of  5 A- 5 A in  FIG. 6A  with a finger pivoting lever arms to the far right when switchpoint  26  is in contact with stockrail  16  in switching or diverging position; 
         FIG. 6A  is a sectional view taken along the plane of  6 A- 6 A in  FIG. 5A ; 
         FIG. 7A  is a side elevation of the railroad switch indicator signaling switching or diverging condition; 
         FIG. 5B  is a side view in section like  FIG. 5A  taken along the plane of  5 B- 5 B in  FIG. 6B  but with the finger pivoting lever arms to the far left when switchpoint  24  is in contact with stockrail  14  in nonswitching, straight or mainline position; 
         FIG. 6B  is a sectional view taken along the plane of  6 B- 6 B in  FIG. 5B ; 
         FIG. 7B  is a side elevation of the railroad switch indicator signaling nonswitching, straight or mainline condition; 
         FIG. 5C  is a side view in section like  FIGS. 5A and 5B  taken along the plane of  5 C- 5 C in  FIG. 6C  but with finger a mid position indicting that the switchpoints are not in proper contact with either stockrail  14  or  16 ; 
         FIG. 6C  is a sectional view taken along the plane of  6 C- 6 C in  FIG. 5C ; 
         FIG. 7C  is a side elevation of the railroad switch indicator signaling danger; 
         FIG. 8  is a detail on an enlarged scale showing a linkage for amplifying the movement of the switchpoints; 
         FIG. 9  is an exploded view of a second railroad switch indicator in accordance with the present invention; 
         FIG. 10A  is a sectional view taken along the plane of  10 A- 10 A in  FIG. 11A  showing the lever arms pivoted to an extreme right with switchpoint  26  in contact with stockrail  16 ; 
         FIG. 11A  is a side elevation of the second railroad switch indicator signaling a switching condition; 
         FIG. 10B  is a sectional view like  FIG. 10A  but with lever arms pivoted to an extreme left with switchpoint  24  in contact with stockrail  14 ; 
         FIG. 11B  is a side elevation of the second railroad switch indicator signaling a nonswitching condition; 
         FIG. 10C  is a side elevation like  FIGS. 10A and 10B  but wherein the arms are not in extreme right or left position indicating that the switchpoints are not in proper contact with either of stockrails  14  or  16 ; and, 
         FIG. 11C  is a side elevation of the second railroad switch indicator signaling danger. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings more particularly by reference character and beginning with  FIG. 1 , reference numeral  10  refers to a railroad switch indicator for use with a railroad switch  12  for switching a railroad train from one track to another. A first railroad switch indicator  10 ′ is shown in  FIGS. 4 through 8  and a second railroad switch indicator  10 ″ is shown in  FIGS. 9 through 11C . 
     Railroad switch  12  normally comprises a pair of fixed outer stockrails  14 ,  16  and pair of inner switchrails  18 ,  20 . Stockrails  14 ,  16  are anchored to a plurality of cross ties  22  in a track bed. Inner switchrails  18 ,  20  have one end rigidly secured to the track bed and the opposite end terminating in laterally spaced switchpoints  24 ,  26  arranged for conjoint lateral movement between laterally spaced switching and nonswitching positions. A transverse bar  28  connects inner rails  18 ,  20  for moving switchpoints  24 ,  26  conjointly from one position to another. Transverse bar  28  may be manually operated or electrically powered by a conventional mechanism  30 . 
     As shown in  FIG. 1 , switchpoints  24 ,  26  are in nonswitching position with switchpoint  24  positioned against stationary left stockrail  14  and switchpoint  26  moved away from stationary right stockrail  16 . In nonswitching position, switchpoint  24  will direct a train entering switch  12  straight through the intersection via right stockrail  16  and switchrail  18  which tapers outward into a straight left rail past switch  12 . In a reverse position (not shown), both switchpoints are moved to the right with switchpoint  24  thus moved away from left stockrail  14  and switchpoint  26  moved to a position against right stockrail  16 . Switchpoint  26  is thus in a position to direct the train to the left via left stockrail  14  which curves to the left past switch  12 , and via right switchrail  20  which tapers outward to a curved right track past switch  12 . 
     With continuing reference to  FIG. 1 , switch  12  is lined against a train curving to the left. If a train runs through switch  12  from the curved section, switchpoints  24 ,  26  will be pushed into a mid position such that they contact neither left nor right stockrails  14 ,  16  and a train coming through switch  12  from bottom to top may derail if the operator depends on the signals associated with mechanism  30  for moving switch points  24 ,  26  if they falsely indicate that switch  12  remains lined for straight through travel. 
     As shown in  FIG. 1 , railroad switch indicator  10  ( 10 ′,  10 ″) operates independently of mechanism  30  and includes a first bracket  32  which is adapted to be attached to one of cross ties  22  near switchpoints  24 ,  26 . For example, when cross tie  22  is formed of metal as shown in  FIGS. 2A-2C , it may include two flanged sections  34   a ,  34   b  separated with insulation such that the metal cross tie does not interfere with electrical signals passed down the track. As shown in  FIG. 3 , bracket  32  includes a triangular shaped plate  36  which is cantilevered to flanged sections  34   a    34   b  of metal cross tie  22  by an L-shaped support  38  as best seen in  FIGS. 11A-11C . Triangular plate  36  is attached to a horizontal leg of L-shaped support  38  by bolts received in elongated holes  40 . Three columns of holes  40  are provided to facilitate mounting on different tracks while elongated holes  40  permit limited lateral adjustment as nuts  42  are tightened. 
     An elongated rectangular sleeve  44  is fixedly mounted on first bracket  32  (e.g., with suitable fasteners or by welding). Sleeve may be given additional support with outriggers  46  mounted on bolts  48  or with bolts  48  threaded into triangular plate  36 . As best seen in  FIG. 3 , a head of bolt  48  may be enlarged for seating on the same cross tie  22  supporting L-shaped support  38 . Nuts  50  fix the length of the bolt shank threaded into outriggers  46  or triangular support plate  36 . 
     In switch indicator  10 ′ as shown in  FIGS. 4 through 8 , sleeve  44  has a top wall  52  and front and rear walls  54 , 56 , respectively, and is mounted between and transverse to stockrails  14 ,  16  ( FIG. 1 ). Throughout the following discussion, it will be understood that the terms front and rear and right and left are arbitrary as those terms are reversed when switch indicator  10  is viewed from an opposite angle. A plurality of regularly formed, spaced apart windows  58  are formed in front and rear walls  54 ,  56 . End caps  60  may be integrally formed with top wall  52  or welded or attached with suitable fasteners. As discussed below, the lower ends of front and rear walls  54 ,  56  may be provided with inwardly directed toes  62  upon which an elongated plate  64  as shown in  FIG. 4  is attached. As shown in FIGS.  4  and  5 A- 5 C, a first slide  66 ′ rides upon elongated plate  64  or as shown in  FIG. 9 , toes  62  may form a slideway for a second slide  66 ″. 
     With reference to  FIGS. 4 through 8 , slide  66 ′ has front and rear elongated walls  68 ,  70 , respectively attached to a top wall  72 . A pair of rollers  74  are provided upon which slide  66 ′ rides on plate  64  in sleeve  44 . A plurality of reflectors  76 , of alternating color such as  76 R and  76 G ( FIGS. 2A-2C  and  FIGS. 7A-7C ) to indicate different track conditions, are provided on front and rear walls  68 ,  70  such that railroad switch indicator  10 ′ ( FIG. 4 ),  10 ″ ( FIG. 9 ) is reversible. In  FIGS. 11A-11C , reflectors  76  are colored green  76 G and amber  76 A with alternating reflectors on front wall  68  in substantial alignment with alternating reflectors on rear wall  70 . Reflectors  76  include reflecting surfaces for reflecting the rays from the headlight of an approaching train, so as to give the operator an indication of the condition of the track or the switch. Reflectors  76  are spaced such that one set of reflectors  76 G is visible through windows  58  when left switchpoint  24  is in contact with left stockrail  18  ( FIG. 2B ) signaling that the track is lined for straight through travel and the other set of reflectors  76 R is visible when right switchpoint  26  is in contact with right stockrail  16  ( FIG. 2A ) indicating that the track is lined to diverge. A mixture of reflectors  76 R and  76 G in  FIG. 2C  (or  76 A and  76 G in  FIG. 11C ) indicates that switchpoints  24 ,  26  are in some mid and dangerous position. 
     As shown in  FIGS. 1 ,  4  and  9 , railroad switch indicator  10  ( 10 ′,  10 ″) includes a second bracket  78  which is adapted to be attached to transverse bar  28  connected to switchpoints  24 ,  26 . A longitudinally extending arm  80  with an upwardly extending finger  82  is mounted on second bracket  78 . As shown in  FIGS. 4 and 9 , arm  80  may be bolted between a pair of L-shaped brackets  84  mounted on a plate  86 . It will be understood that this arrangement permits finger  82  to be moved towards and away from first bracket  32 . Thus finger  82  may be made to pass through a first slot  88  ( FIG. 4 ) provided in first bracket  32  and a second, aligned slot  90  in plate  64  best seen in  FIG. 8  for reciprocation of slide  66 ′ within sleeve  44  conjointly with movement of transverse bar  28  with switchpoints  24 ,  26 . 
     As seen in  FIG. 8 , reciprocation of slide  66 ′ is through a linkage  92 ′ accessible through slot  90  of plate  64 . Linkage  92 ′ includes first and second lever arms  94 ,  96 , a first end of which is pivoted on plate  64  of sleeve  44 . As shown, lever arms  94 ,  96  are parallel and pivoted on one side of slot  90 . The pivot points of lever arms  94 ,  96  may be adjustably spaced by use of holes  98 . A second end of first and second lever arms  94 ,  96  is attached to a first link  100 . First link  100  like plate  86  includes holes  98  for use in spacing the pivot points of first and second lever arms  94 ,  96 . 
     A free end of first link  100  is pivoted to a second link  102  which is adjustable in length with elongated slots and bolts to adjust the linkage  92 ′ such that the reflectors  76 R or  76 A and  76 G are properly aligned with windows  60  when switchpoints  24 ,  26  are in switching or nonswitching position. Second link  102  is pivoted to a third arm  104  which like first and second arms  94 ,  96  is pivoted at a first end to plate  86  which forms the bottom wall of sleeve  44 . A second end of third arm  104  is pivoted to a third link  106  which is connected to a side wall of slide  66 ′ by a bracket  108  as best seen in  FIG. 8 . When finger  82  contacts either first or second lever arm  94 ,  96 , the distance traveled by the second end of the lever arm is greater than the distance traveled by finger  82 . This distance is further amplified by third arm  104  and transferred to slide  66 ′ by third link  106 . For example, in one embodiment of switch indicator  10 ′, linkage  92 ′ amplified a ¼ inch movement of switchpoints  24 ,  26  into a 1.6 inch movement of slide  66 ′. This movement was designed to be one-half the width of reflectors  76  such that railroad switch indicator  10 ′ signals danger with less than a ¼ inch movement of the switchpoints. In practice, it has also been found that railroad switch indicator  10  ( 10 ′,  10 ″) is more sensitive if longitudinally extending arm  80  or finger  82  is slightly flexible such that when pressure on lever arms  94 ,  96  is released, slide  66 ′ ( 66 ″) is sprung into in mid position more quickly. It will be apparent that even larger movements of slide  66 ′ may be obtained if a fourth lever arm or more (not shown) are added to linkage  92 ′. Amplification of the movement can also be obtained by increasing the length of the lever arms  94 ,  96 . 
     As viewed in  FIGS. 5A ,  6 A and  7 A, when finger  82  pivots lever arms  94 ,  96  to the extreme right first set of reflectors  76 R are visible through windows  58  of sleeve  44  indicating that the switchpoints are in switching or diverging position. When finger  82  pivots lever arms  94 ,  96  to the extreme left as shown in  FIGS. 5B ,  6 B and  7 B, second set of reflectors  76 G are visible through windows  58  of sleeve  44  indicating that the switchpoints are in nonswitching, straight or mainline position. 
     With finger  82  not pressed hard against lever arms  94 ,  96 , slide  66 ′ is urged to center position by a biasing system. As shown in  FIGS. 5C ,  6 C and  7 C, this is signaled by first and second set of reflectors  76 R or  76 A and  76 G, portions of which are visible through windows  58  of sleeve  44 . A first biasing system  110  includes a tongue  112  which is sandwiched between opposing springs  114 ,  116  mounted on an underside of top wall  52  of slide  66 ′. Top wall  72  of slide  66 ′ has elongated aperture through which tongue  112  sticks. Tongue  112  is received in a slot of a bracket  118  that bridges front and rear walls  68 , 70  of slide  66 ′. When finger  82  pivots lever arms  94 ,  96  to the right one of springs  114 ,  116  is compressed and the other spring is compressed when finger  82  pivots lever arms  94 ,  96  to the far left. When finger  82  is not pressed hard against lever arms  94 ,  96 , tongue  112  is urged center by springs  94 ,  96  causing slide  66 ′ to move into mid position. 
     A second biasing system  120  for moving slide  66 ′ into center position signaling danger includes a pair of pivoted counterweights  122 ,  124 . A rod  126  is provided between front and rear walls  68 ,  70  and between first and second counterweights  122 ,  124 . When finger  82  pivots lever arms  94 ,  96  to the right as shown in  FIGS. 5A ,  6 A and  7 A, counterweight  124  is lifted by rod  126  and when finger  82  pivots lever arms  94 ,  96  to the left as shown in  FIGS. 5B ,  6 B and  7 B, counterweight  122  is swung up by rod  126 . When finger  82  contacts neither of lever arms  94 ,  96  as shown in  FIGS. 5C ,  6 C and  7 C, whichever of counterweights  122 ,  124  was lifted, pushes slide  66 ′ into mid position with rod  126 . 
     The spacing between the pivot points of lever arms  94 ,  96  on plate  86  and first link  100  may be adjusted with holes  98  such that arms  94 ,  96  are in extreme right and left position when the switchpoints are in nonswitching and switching position, respectively. For this it has been found advantageous that the innermost holes  98  be 3½ inches apart. The spacing between the other holes may be different for finer adjustment of the spacing between the pivot points. For example, the spacing may be ½ inch for the holes on the left as viewed in  FIG. 8  and 5/16 and ⅜ inch for the holes on the right. 
     Railroad switch indicator  10 ″ as shown in  FIGS. 9 through 11C  is similar to switch indicator  10 ′ in many respects. It differs in that slide  66 ″ has a closed bottom  128  with toes  62  of sleeve  44  forming a slideway for slide  66 ″ Like plate  86  of slide  66 ′, bottom  128  has a slot  90  through which finger  82  passes for engagement with a linkage  92 ″. In linkage  92 ″, first end of first and second lever arms  94 ,  96  is pivoted to sleeve  44  and second end is pivoted to slide  66 ″. As above mentioned, the distance that finger  82  moves slide  66 ″ is amplified by lever arms  94 ,  96  but not to extent that movement of slide  66 ′ is amplified. For example, it may take a movement of ⅝ inch of switchpoints  18 ,  20  to move slide  66 ″ 1.6 inch whereas that distance is achieved with a movement of ¼ inch with railroad switch indicator  10 ′. Another difference between the railroad switch indicators is that in railroad switch indicator  10 ″ the distance between the pivot points of lever arms  94 ,  96  is fixed. To adjust for the throw of finger  82  between switching and nonswitching position, first and second bolts  130 ,  132  are threaded into lever arms  94 ,  96 . Finger  82  contacts the heads of bolts  130 ,  132 . Bolts  130 ,  132  are threaded into lever arms  94 ,  96  a distance such that when finger  82  contacts the bolt  132  and pushed lever arms  94 ,  96  to far right, switchpoints  24 ,  26  are in switching or diverging position indicated by reflectors  76 A and when finger  82  contacts bolt  130  and pushed lever arms  94 ,  96  to far left, switchpoints  24 ,  26  are in nonswitching, straight or mainline position which is signaled by reflectors  76 G. In between position, slide  66 ″ is released and pushed into mid position. Biasing system  134  in railroad switch indicator  10 ″ is different from  10 ′ described above. As shown, compression springs  136 ,  138  are provided at oppose ends of slide  66 ″ between end caps  60  of sleeve  44  and an end wall  140  of slide  66 ″. When not compressed by action of finger  82  on lever arms  94 ,  96 , springs  136 ,  138  tend to bias slide  66 ″ into a mid position signalizing danger with a mixture of reflectors  76 A and  76 G. 
     In use, it is seen that railroad switch indicators  10 ′ and  10 ″ operate independently of the mechanism for operating switch  30  and have increased sensitivity to movement of switchpoints  24 ,  26 . Because railroad switch indicators  10 ′ and  10 ″ are mechanically linked to switchpoints  24 ,  26 , operation of the indicator does not depend on electricity. 
     In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained. As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.