Patent Publication Number: US-4544124-A

Title: Mounting for caboose replacement signal transmitting unit

Description:
BACKGROUND OF THE INVENTION 
     The elimination of the caboose from freight trains and its replacement by an electronic signal transmitting unit has given rise to problems concerning a safe and efficient mounting means for the transmitting unit. As is well known, this unit transmits signals to the locomotive indicating the presence or absence of brake pressure, when the last car of the train has stopped, and when the last car begins to move with the train. 
     Heretofore, it has been customary to provide a depending mounting pin on the signal transmitting box or unit, which pin engages supportingly in a vertical axis signal flag opening in the pivoted coupling knuckle of the rearmost car. Two problems are encountered with this mounting arrangement. First, in many instances, the signal flag opening is mashed or distorted so that it cannot accept the depending mounting pin of the signal transmitting unit. Second, the pin and signal flag opening are relatively small in cross section, preventing the slender pin from supporting the transmitting unit at a sufficient elevation to avoid destruction of the unit by the crown portion of an oncoming car coupler. Both of these problems are completely overcome by the present invention which provides a mounting for the transmitting unit which is much more stable while having the ability to support the transmitting unit above the elevation of coupling crowns. The mounting according to the present invention allows safe coupling of a car behind the car on which the signal transmitter is mounted without endangering the transmitter or its mounting and without interfering with the coupling operation. 
     A further feature of the invention resides in the minimizing of metal-to-metal contact between the mounting and coupling knuckle in order to reduce electrolysis. The efficient mounting is convenient to install and remove, sturdy and durable, and relatively inexpensive. 
     Other features and advantages of the invention will become apparent to those skilled in the art during the course of the following detailed description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a plan view of a mounting for a caboose replacement signal transmitting unit with coacting car coupling components being shown in phantom lines. 
     FIG. 2 is a side elevational view of the mounting. 
     FIG. 3 is a horizontal section taken on line 3--3 of FIG. 2. 
    
    
     DETAILED DESCRIPTION 
     Referring to the drawings in detail wherein like numerals designate like parts, a mounting for a caboose replacement signal transmitting unit 10 comprises a bifurcated mounting bracket 11 having two parallel leg portions 12 and 13 adapted to straddle the knuckle 14 of the coupling on the rearmost car of a train on which the electronic signal transmitting unit 10 requires mounting. 
     Referring to FIGS. 1 and 2, the mounting structure takes advantage of the fact that the width of the coupling knuckle 14 in the front-to-back direction which is straddled by the leg portions 12 and 13 is a standard dimension in all makes or models of car couplings, which in other respects can vary in construction and design. 
     The coupling knuckle 14 is conventionally pivotally held on a coupling yoke 15 connected with the rear truck of the car on which the unit 10 is mounted, the rear end of such car being indicated at 16. The coupling yoke 15 includes a rising crown 17 which is a safety buffer to prevent an oncoming rail car coupling from riding up on top of the yoke 15 and possibly damaging the car to which the yoke is attached. As shown in FIG. 2, the transmitting unit 10 is supported above the elevation of the crown 17 to avoid destruction of the unit 10 by the crown of an oncoming car behind the car 16, in accordance with an important feature of this invention. 
     The rear leg portion 12 of mounting bracket 11 consists of a comparatively wide flat vertical plate, FIGS. 1 and 3, and the forward leg portion 13 consists of a relatively narrow and somewhat thinner plate. The two leg portions 12 and 13 are joined at their tops by a horizontal wall 18 which is trapezoidal in shape, FIG. 1. A vertical plate extension 19 forming a continuation of the leg portion 12 extends above the wall 11 and is supportingly connected with the electronic signal transmitter box or unit 10 to support the same securely and safely above the crown 17, for the reason already stated. 
     At its lower end, the bracket 11 carries a hasp plate 20 connected by a horizontal axis piano hinge 21 to the lower end of leg portion or plate 12 whereby the hasp plate 20 is swingable between a horizontal locked position and a release position shown in broken lines in FIG. 2. The hasp plate 20 is also trapezoidal and somewhat larger than the top wall 18, as indicated in FIG. 1. 
     The forward relatively narrow end of the hasp plate 20 contains an oblong opening 22 adapted to receive therethrough a lower end extension 23 of leg portion or plate 13, which extension is apertured to receive the shackle 24 of a padlock 25 below the hasp plate 20 to lock the mounting on the coupling knuckle 14. The padlock is preferably tethered to the bracket 11 through a suitable tether, not shown. 
     To eliminate electrolysis caused by direct metal-to-metal contact between the bracket 11 and knuckle 14, upper and lower hard rubber engaging strips 26 are provided on the forward face of plate 12 and directly engage the rear face of knuckle 14. A comparatively narrow hard rubber strip 27 is similarly provided on the rear face of vertical plate 13, or leg portion, and directly engages the curved frontal face of the knuckle 14. These rubber components also enable a relatively snug fit for the mounting on the coupling knuckle without appreciable movement, thus reducing wear. 
     Top and bottom opposite side forwardly converging metal stabilizing teeth 28 and 29 are provided on the bottom of the horizontal wall 18 and the top face of hasp plate 20. The teeth 28 and 29 which are vertically disposed are embodied in the vertical webs of short sections of angle bars whose horizontal webs 30 are fixed to the wall 18 and hinged hasp plate 20 as by welding. 
     Inasmuch as the coupling knuckle 14 becomes gradually thicker in its vertical dimension toward its terminal end 31, FIG. 1, commencing at a region approximately indicated by the numeral 32 where the knuckle has a constant thickness, the engaging teeth 28 and 29 are of different lengths, as clearly shown in FIG. 2. The longer teeth 29 have their tips engaging the top and bottom surfaces of knuckle 14 in the region 32 of constant and lesser thickness, while the relatively shorter teeth 28 have their tips engaging the top and bottom faces of the knuckle 14 at points of increasing thickness toward the thickest portion 31. The teeth 28 and 29 are also tapered in profile, FIG. 2, to minimize metal-to-metal contact with the knuckle, again for the purpose of avoiding electrolysis. The opposing top and bottom sets of teeth provide stability for the mounting in the vertical direction. 
     It should now be apparent that a simplified and secure mounting for the electronic signal transmitting unit 10 replacing the customary caboose is provided. The mounting is adaptable to all makes of car couplings because of the standard dimension front-to-back across the knuckle 14. By having the mounting bracket 11 straddle the knuckle 14 and locking it beneath the knuckle, all of the problems of the prior art occasioned by utilizing the signal flag aperture 33 of the knuckle 14 to support a spike-type mounting for the unit 10 are avoided and eliminated. The numerous advantages of the invention over the prior art should now be readily apparent to those skilled in the art without the necessity for further description. 
     The terms and expressions which have been employed herein are used as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof but it is recognized that various modifications are possible within the scope of the invention claimed.