Abstract:
An improved wick-holder for mounting a felt lubricating wick of a lubricating system for lubricating the axle journal surface supported in a support bearing of a traction motor used in a locomotive is provided with a plurality of oil-reservoir louver pockets or splash-cups molded or pressed into the wick holder which store oil from the time that the oil reservoir was full or near its maximum height and which store splashed oil during normal operational use, and delay the run off of the oil to increase the oil saturation of the wick housed within the wick holder. The oil reservoir pockets are located above the minimum serviceable oil level, and are designed to improve and increase oil saturation of the wick. As a result of the increased oil saturation, the wick are, therefore, capable of delivering increased amounts of oil to the axle journal area. The increased amount of oil saturation and reduced wicking height provide increased protection against traction motor support bearing failure if a locomotive is used with axle journal oil levels near the recommended minimum oil levels. Each reservoir pocket or splash cup is preferably louver-shaped, whereby during normal locomotive operating service, the splashing of oil in the bearing housing oil reservoir is collected and delivered to the lubricating wick. In a second embodiment, the reservoir pockets or splash cups are provided on a separate splash sleeve telescopingly mounted over, and to, the lower, free end of the central lubricating wick

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention is directed to an improved wick holder used in a lubricating system for lubricating the axle-journal surface mounted in a support bearing of a locomotive traction motor. The wick holder supports and mounts a central lubricating wick having a lower end portion or section received in an oil reservoir, which oil, via capillary action, is delivered by the wick to the axle-journal surface by means of a window formed in the shell of the traction motor support bearing. The other, upper wick-face section of the wick is received in the window for contact against the axle-journal surface, to thereby provide the proper lubrication.  
         [0002]     Examples of this lubricating system are disclosed in the U.S. Pat. Nos.: 2,980,472; 3,827,769; 3,905,659; 4,229,056; and 5,082,089. One such prior-art system is also shown in  FIG. 1 , and is indicated generally by reference numeral  10 , and includes an oil reservoir  12  for storing lubricant, and a carrier assembly  14  connected to the axle cap  16  of a friction support bearing  18  used for mounting a locomotive traction motor to the wheel axle assembly. The carrier assembly  14  has a spring  22 , such as a coil or torsion spring, that biases a wick-holder unit  34  toward a window  26  formed in the shell of the friction support bearing  18 , through which window oil is delivered to the axle-journal surface  37  mounted in the friction support bearing.  
         [0003]     The wick-holder unit consists of a slide bracket element or member  32  which is mounted for sliding movement in the carrier assembly  14 , a wick holder member  34  of arcuate shape that is connected to the slide bracket element  32 , and a felt wick  36  having an upper section of similar arcuate shape mounted in the wick holder  34 .  
         [0004]     The above-described wick lubricator assembly of the prior art, however, has serious shortcomings. Specifically, these prior art oil-lubricating delivery systems have decreasing ability to deliver a continuous amount of oil to the axle-journal surface area as the oil level in the journal box is consumed over time, as the oil level in the oil reservoir decreases, even though the wick had initially absorbed oil to saturation.  
         [0005]     When a new traction motor/axle wheel set of a locomotive is placed into service, it has approximately twelve pints of journal oil added to the bearing oil reservoir. Capillary-oil lift is typically less than two inches. During normal operation, the oil is consumed and the oil level in the reservoir continues to drop, resulting in reduced oil-saturation of the felt wick. As a result, the oil delivery-rate is reduced in inverse proportion to the increased required oil-wicking height. The result of this reduced oil delivery can be a repetitive cycle of reduction in the load bearing capacity of the journal and an increase in the operating temperature of the bearing each time the locomotive accumulates mileage between normal servicing. As a result of this reduction of lubrication delivered to the journal, the margin of excess bearing capacity can be reduced such that a condition is created that can end in a failure of the bearing and axle.  
         [0006]     It would, therefore, be advantageous to provide an improved wick-lubricating delivery system for an axle-journal surface supported by a friction bearing of a locomotive traction motor that diminishes the adverse effect of oil depletion in the journal box and oil reservoir, in order to continue to supply the requisite lubricating oil to the axle-journal, thereby reducing railroad operating expenses by improving reliability and length of service of the existing traction motor/axle-wheel set combination.  
       SUMMARY OF THE INVENTION  
       [0007]     It is, therefore, the primary objective of the present invention to provide an improved wick-holder for a wick lubricating system for the axle-journal surface supported by a friction support bearing of a locomotive traction motor which delivers a greater amount of oil even as oil is depleted from the oil reservoir.  
         [0008]     In accordance with the present invention, an improved wick-holder for mounting a felt lubricating wick is provided with a plurality of oil-reservoir pockets or cups molded or pressed into the wick holder which store oil from the time that the oil reservoir was full or near its maximum height. These reservoir pockets also collect oil that has been splashed or sloshed within the oil reservoir during normal locomotive operation, thereby delaying the run off of the oil and to increase the oil saturation of the wick housed within the wick holder. These oil reservoir pockets are located above the minimum serviceable oil level, and are designed to improve and increase oil saturation of the wick. As a result of the increased oil saturation, the wick is, therefore, capable of delivering increased amounts of oil to the axle-journal surface. This increased amount of oil saturation provides better protection against axle-journal bearing failure in the event that a locomotive is operated with insufficient or diminished oil levels. It also provides reduced wicking height. Felt wicks exhibit an ability to be saturated with liquids and lift the liquids above the level of the liquid in a reservoir. This ability is called “wicking height” and is measured in linear graduations after a given period of time while the viscosity of the liquid is maintained at a standard value. The higher the wick is sampled above the reservoir, the smaller the percent of saturation is encountered. In accordance with the improved wick holder of the invention, when lubricant is artificially introduced via the collection reservoir pockets during splashing of oil in the oil reservoir, the percent saturation above these locations will be increased and, in turn, the lubricant available at the delivery wick-face will be increased. The increased oil saturation at an intermediate height of the wick will reduce the required wicking height of the wick, therefore allowing a greater amount of oil lubrication at the axle journal. The increased wick saturation and delivery rate act to reduce wick-face temperatures and extend the life of the wicks. The increased amount of oil saturation and reduced wicking height provide increased protection against traction motor support-bearing failure if a locomotive is used with axle-journal oil levels near the recommended minimum oil levels. In addition, the increased saturation may increase time interval between scheduled wick replacements.  
         [0009]     The reservoir pockets are preferably shaped as louvers, whereby during normal locomotive operating service, with the traction motor being subject to significant “g” force acceleration, “oil sloshing” and “oil splash” in the bearing-housing oil reservoir occur, whereby these louver-shaped splash cups or pockets of the wick holder of the present invention capture or collect oil as it sloshes or splashes during locomotive service. The captured oil is immediately absorbed into the wick&#39;s felt material and then transferred to the axle-journal surface area by capillary action.  
         [0010]     In a second embodiment of the invention, a splash sleeve made of metal or elastomeric material is provided that slides over the tail or lower end section of the existing felt wick lubricator. This splash sleeve is used to encase the lower end portion of the wick below the existing wick support holder. The splash sleeve preserves the maximum possible exposure of the felt wick to lubrication oil, while introducing splash louvers on each side of the lubricator pad. The splash sleeve is preferably held in place by, for example, a retaining pin that passes through the sleeve and between the two felt layers of the felt wick, and rests upon the main bodies of the two rivets which clamp these two felt layers together.  
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0011]     Reference is had to the drawings, wherein:  
         [0012]      FIG. 1  is a partial vertical cross-sectional view of a prior-art locomotive traction support bearing and axle cap, and showing the prior-art lubricating system;  
         [0013]      FIG. 2A  is a partial vertical cross-sectional view of a locomotive traction support bearing and axle cap, and showing a first embodiment of the improved lubricating system of the invention;  
         [0014]      FIG. 2B  is a side elevational view of the first embodiment of  FIG. 2A  showing the wick holder in isolation, incorporating the louver-shaped reservoir pockets of the invention;  
         [0015]      FIG. 2C  is a partial cross-sectional rear view of the wick holder of  FIG. 2B , showing the louver-shaped reservoir pocket of the invention which had been formed by punching out material from the wick holder itself;  
         [0016]      FIG. 3  is a first isometric view of a second embodiment of the invention where a splash sleeve incorporating louvers which in combination with the wick form reservoir pockets is used for attachment over the bottom or lower portions of a wick lubricator;  
         [0017]      FIG. 4  is a second isometric view of the second embodiment of the invention of  FIG. 3 ;  
         [0018]      FIG. 5  is a plan development view of a metal forming the splash sleeve of  FIG. 3 , prior to forming the sides thereof;  
         [0019]      FIG. 6  is an end view thereof;  
         [0020]      FIG. 7  is a partial vertical cross-sectional view of a locomotive traction support bearing and axle cap, and showing the splash sleeve of the second embodiment of the invention mounted in place over a lubricating wick;  
         [0021]      FIG. 8A  is a side elevational view of the second embodiment of  FIG. 3  showing the wick holder incorporating the splash sleeve of the second embodiment;  
         [0022]      FIG. 8B  is a plan view of a retaining pin for fastening the splash sleeve of the second embodiment to the felt wick;  
         [0023]      FIG. 9  is a side elevational view similar to  FIGS. 2B and 8A  of a third embodiment of the invention which is a combination of the first embodiment of  FIG. 2A  and the second embodiment of  FIG. 4 ;  
         [0024]      FIG. 10A  is a rear, plan view of a fourth embodiment of the invention similar to the first embodiment of  FIG. 2A  but incorporating only one reservoir pocket of the invention, on the interior, or bearing-facing, surface of the wick-holder;  
         [0025]      FIG. 10B  is a partial side elevational of the fourth embodiment of  FIG. 10A ;  
         [0026]      FIG. 11A  is a rear, plan view of a fifth embodiment of the invention similar to the first embodiment of  FIG. 2A  where the wick holder is extended downwardly in the interior, or bearing-facing, surface for providing additional reservoir pockets or compartments facing interiorly toward the bearing surface;  
         [0027]      FIG. 11B  is a partial side elevational of the fifth embodiment of  FIG. 11A ;  
         [0028]      FIG. 12A  is a front, plan view of a sixth embodiment of the invention similar to the fifth embodiment of  FIG. 11A  but where the wick holder is extended downwardly in the exterior, or outwardly-facing, surface thereof for providing additional reservoir pockets or compartments facing the exteriorly away from the bearing surface;  
         [0029]      FIG. 12B  is a partial side elevational of the sixth fifth embodiment of  FIG. 12A ; and  
         [0030]      FIG. 13  is an isometric view similar to  FIG. 4  but showing the retaining pin in place for securing the splash sleeve of  FIG. 4  on the lower end of the lubricating wick;  
         [0031]      FIG. 14  is an end view thereof;  
         [0032]      FIG. 15  is a side view thereof; and  
         [0033]      FIG. 16  is a graph showing the improved oil delivery rate of the wick lubricator according to the invention versus the prior art. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0034]     Referring now to the drawings in greater detail, and to  FIGS. 2A-2C , there is shown the first embodiment of the improved wick holder of the invention. The wick holder  40  of the first embodiment of the invention is similar to that utilized in the conventional wick holder assembly  10  of the prior described hereinabove with reference to  FIG. 1 , with the exception that wick holder member  44 , which is similar in arcuate shape as the wick holder member  34  of the prior art, is provided with two reservoir louver pockets or collectors  46 ,  48 , at a location along the height of the wick holder member  44  that is above the minimum serviceable oil level of the oil reservoir  12 . The two louver pockets  46 ,  48  are provided along the main elongated front and rear surfaces of the wick holder element  44 , and at an approximate height where the wick holder&#39;s curvature is most pronounced, although other heights are also suitable. The first, inwardly-facing reservoir louver pocket  46  is formed on the bottom or rear, interior-facing wall or surface  42 ′ of the wick holder, while the reservoir louver pocket  48  is formed on the upper or front surface or wall  42 ″ facing away from the bearing surface. Owing to the curvature of the wick holder  40 , the front reservoir louver  48  is at a higher elevation than that of the lower reservoir louver. The lower reservoir louver  46 , being closer to any minimum serviceable oil level on the oil reservoir  12 , serves to collect and provide oil to the lubricating wick during such minimum level as compared with the upper reservoir louver.  
         [0035]     The location of these reservoir louvers  46 ,  48  are such that, when the oil level in the oil reservoir tank  12  falls to a level below the cups  46 ,  48 , the reservoir louvers  46 ,  48 , collect oil that has been splashed within the reservoir during normal locomotive operation, and delay the run off of the oil to increase the oil saturation of the wick housed within the wick holder, in order to continue to provide additional wick-lubrication from internal oil-splashing and sloshing, even after the oil level falls to a minimum serviceable level below the height of the reservoir louvers  46 ,  48  due to the normal splashing and sloshing of the oil in the reservoir  12  during normal operation of the locomotive. The splashed oil is collected in each reservoir louver via each upwardly-facing opening  46 ′,  48 ′, respectively, and delivered to the felt wick lubricator via an opening  46 ″ formed in the wick-holder member in opposite juxtaposition to each louver  46 ,  48  as seen in  FIG. 2C . As may be seen in  FIG. 2C , each reservoir louver pocket is formed by punching out a portion of the material of the wick holder, to thus form the upwardly-facing openings or mouths  46 ′,  48 ′, respectively, and to also form the front wall  50  thereof. In the preferred form of the invention, the lower, rear louver is less than two inches away from the wick delivery face of the wick, although this distance may be changed.  
         [0036]     The splash reservoir louvers  46 ,  48  are initially submerged under the oil-line of the oil reservoirs during normal use. As the oil is consumed during normal service-operation of the locomotive, with the concomitant falling of the oil level below the splash reservoir louvers  46 ,  48 , oil saturation of the wick material is restored at the intermediate point of the wick from the oil stored in these splash reservoir louvers and directed toward the wick. While the reservoir louvers  46 ,  48  are submerged in the oil, they continue to feed the felt and maintain maximum wick oil saturation in parallel with the wick-tail immersion. During locomotive operating service, the journal oil in the bearing housing reservoir is sloshed and splashed within the bearing housing reservoir, and continuously refills the splash louvers to maintain maximum oil saturation of the wick material, even after the oil level in oil-reservoir  12  has fallen below the entrance mouths  46 ′,  48 ′.  
         [0037]     Referring now to  FIGS. 3-8 , there is shown a second embodiment of the invention. In this embodiment, a separate, independent splash sleeve  60  is used that slides over, or is telescopingly received about, the free end-portion  36 ′ ( FIG. 1 ) of the felt wick lubricator stationed in the oil reservoir. This free end-portion of the wick lubricator  36  is that which projects downwardly from the wick holder, such as wick holder  34  of  FIG. 1 .  
         [0038]     The hollow splash sleeve  60  is made of metal, plastic, or other suitable material, and is preferably rectilinear in cross section to match the shape of the felt wick lubricator  36  over which it is received. The splash sleeve  60  is provided with a series or plurality of elongated openings  62  on all four surface walls in order to allow the oil stored in the oil reservoir  12  to pass therethrough and lubricate the felt wick lubricator. These openings  62  are necessary since the slash sleeve covers the portion of the felt lubricator that is usually positioned within or inside the oil of the oil reservoir during at least the higher oil levels of the reservoir.  
         [0039]     The splash sleeve  60  is also provided with a series or plurality of oil-collecting reservoir pockets or cups  64  on each of the longer rear and front walls  60 ′,  60 ″ of the splash sleeve. Each pocket or cup  64  may be a louver similar to those described hereinabove with respect to the first embodiment, but in the preferred embodiment are pockets or cups, that are arranged in a vertical array where each is parallel to another, although different formations may be utilized, as well as more or less than the three cups  64  shown in the drawing for each of the front wall surface  60 ′ and rear wall surface  60 ″.  
         [0040]     Each cup  64  has an upper opening or mouth formed to form a front wall  66  and side walls  66 ′,  66 ″, which form a temporary reservoir for delivering the oil splashed therein during normal operation of the locomotive, for subsequent delivery to the felt wick located within the splash sleeve, via openings  70  cut out of the splash sleeve during formation of each cup  64 , similar to the opening  46 ′ of  FIG. 2C . As can be seen in  FIG. 7  and  8 A, the splash sleeve  60  covers the lower exposed portion  36 ′ of the wick lubricator extending or protruding from the bottom of the wick holder  34 .  
         [0041]     Referring to FIGS.  8 B and  13 - 15 , there is shown the manner by which the splash sleeve  60  is secured or mounted about the wick lubricator by means of, for example, a retaining pin  70 ′ that passes through oppositely-aligned openings  62 ′ of the side walls  64 ′,  66 ′ of the sleeve  60  and through the interface of the felt layers of the felt wick lubricator. The retaining pin  70 ′ has a first tapered end  72  to aid in the insertion of the pin through and between the felt layers of the wick lubricator, and a second enlarged end  74  defining an annular retaining groove  76  for receiving therein portions of the circumferential rim in an opening  62 ′ in one of the side walls  64 ′,  66 ′ through which the pin has been passed, to retain the pin in place. The portion of the pin  70 ′ directly adjacent to, and inwardly of, in a direction taken from the enlarged end  74  toward the tapered end  72 , is canted or sloped in order to provide a snap-fit type of connection. The pin  70 ′ is preferably oval in cross section as the shape of the openings  62 ′ of the side walls  64 ′,  66 ′. However, other cross-sectional shaped may be employed, with the openings in the side walls through which is passes being of similar cross section and matching dimensions. As may be seen in  FIGS. 13-15 , the retaining pin  70 ′ rests upon the conventional two rivets  70 ″ that hold two felt layers of the conventional wick together at the bottom or wick tail-end of the lower exposed portion  36 ′ of the wick, thereby supporting and retaining the splash sleeve on the wick tail-end of lower exposed portion  36 ′. As seen in  FIGS. 13-15 , when mounting the splash sleeve to the lower, or tail-end, of the lubricating wick, the retaining pin is inserted at the interface between the two felt-layers of the wick and rests upon the two spaced-apart rivets, which extend perpendicularly to the length of the retaining pin  70 ′, which rivets, in the conventional manner, secure the two felt-layers of the wick together. It is, of course, possible to secure or mount the splash sleeve to the wick in other ways or manners.  
         [0042]     Referring to  FIG. 9 , there is shown yet another embodiment of the invention which is a combination of the first two embodiments. In this embodiment, the wick holder  80  is the same as the wick holder  40  of  FIG. 2A-2C , with the two reservoir louvers  46 ,  48 . In order to enhance even more the lubrication of the wick, the splash sleeve  60  of the second embodiment of  FIGS. 3-8  is also simultaneously employed over the cantilevered end of the felt lubricating wick, as described hereinabove with reference to Figs,  3 - 8 . In this embodiment, as shown, the reservoir collectors  64 ′ are shaped as louvers, as in the reservoir louvers  46 ,  48  of the wick holder.  
         [0043]      FIGS. 10A and 10B  show a modification of the first embodiment of  FIGS. 2A-2C , where instead of utilizing two louver-shaped reservoir pockets or cups  46 ,  48 , only the inner, or bearing-support facing, reservoir pocket  46  formed in the rear wall of the wick holder is used .  
         [0044]      FIGS. 11A and 11B  show a modification of the embodiment of  FIGS. 9A-9B , where the wick holder  90  is similar to wick holder  40  of  FIG. 2A-2C , but with an interior and downwardly-projecting extension  92  extending integrally from, and serving as an extension of, the rear wall or surface  42 ′. Punched out of this rear-wall extension  92  are a plurality of the reservoir louvers  92 ′. The length of the extension  92  may vary depending upon lubricating requirements. The extension  92  preferably extends about one inch from the main wick frame, although this length may be different.  
         [0045]      FIGS. 12A-12B  show yet another modification similar to the modification of  FIGS. 11A and 11B , but instead of a rear-wall extension having louver-shaped reservoir cups formed therein, the wick holder  100  of this modification has an exterior and downwardly-projecting extension  102  extending integrally from, and serving as an extension of, the front wall or surface  42 ″ of the wick holder  40  of the first embodiment of  FIGS. 2A-2 . Punched out of this rear-wall extension  102  are a plurality of the louver-shaped reservoirs  104 . The length of the extension  102  may vary depending upon lubricating requirements. It is also noted, that in this modification, the front or upper surface  42 ″ of the wick holder is provided with three separate louver reservoir pockets: A central one  106 , and two end ones  108 ,  110 , instead of the one louver-shaped reservoir  48  of  FIG. 2A-2C . The extension  102  preferably extends about one inch from the main wick frame, although this length may be different.  
         [0046]     Referring now to  FIG. 16 , there is shown a graph depicting the enhanced lubrication of the friction support bearing utilizing the invention in contradistinction to the lubrication of achieved in a conventional unit, and shows wick-oil delivery rate vs. oil consumption, that is, the oil level of the reservoir  12 . The upper line “A” represents the maximum improvement of oil delivery rates according to the present invention, while the lower line that of the prior-art system. As can be seen, while at the beginning, immediately after servicing, the rates for both are the same (y-axis intercept), where the oil in the reservoir  12  is at its maximum. Over time, however, as oil is consumed during normal usage, the oil delivery rate provided by that of the present invention is consistently greater, with the difference in the delivery rate between that of the present invention and that of the prior art system, increasing the greater the drop in the level of the oil in the reservoir  12 . The line “B” represents this range of possible improvement in the oil delivery rate between the system of the present invention and that of the prior art.  
         [0047]     The length of the reservoir pocket of the invention is preferably approximately three inches in length, although each may be made shorter or longer.  
         [0048]     In order to explain the enhanced lubrication provided by the louver-shaped reservoir pockets of the invention, the oil delivery rate is defined by the following equation: 
 
Oil Delivery= Q=[K   u   AF   o ( h   u   −h )]/μ L =5 max. cm 3 /min 
        where,     K u =approximately 4.6 for mineral oil and SAE grade F-1 felt,     A=cross-sectional area of the wick (cm 2 ),     F o =volume fraction of oil in saturated wick (approximately 0.75),     (h u −h)=vertical lift [ultimate lift ability of SAE grade F-1 felt (about 18 cm] minus the elevation of the wick face above the oil supply],     μ=approximately 58 centipoise viscosity at 40 degrees C. oil temperature;     L=distance from the wick delivery face to the point of absorption (cm).        
 
         [0056]     The two terms (h u −h) and L are the ones that are favorably effected by the addition of the oil reservoir pockets of the invention. The term (h u −h) is increased in magnitude as the required lift is decreased by introduction oil above the reservoir surface. At the same time, the term L is decreased as the oil travels as shorter distance from the point of absorption to the point of delivery.  
         [0057]     While the reservoir louver pockets of the invention have been described as being louver-shaped, it is understood that such is not meant to be limiting, and that it is also within the scope and purview of the invention to use reservoir pockets that are of different shape and configuration, as long as the oil being splashed during operation is trapped therein and then delivered to the lubricating felt wick, especially during oil levels in the oil reservoir approaching the minimum serviceable operational level. Moreover, while it has been stated that these reservoir cups or pockets are punched out of the wick holder itself, or punched out of the splash sleeve or wall-extensions of the wick holder, other methods may be employed.  
         [0058]     It is also to be understood that while the oil-reservoir pockets of the invention have been shown to be part of a specific type of wick holder, such as that shown in U.S. Pat. Nos. 3,827,769 and 5,082,089, they may easily and readily be employed in other and all types of wick holders, such as those disclosed in U.S. Pat. Nos. 2,980,472 and 3,905,659, as well as others, and no limitation has been meant with disclosure of the reservoir pockets of the invention provided in one kind of wick holder.  
         [0059]     With regard to the splash sleeve of the second embodiment of  FIGS. 3-8 , it is also possible to eliminate most of the side walls of the splash sleeve  60  that connect the rear and front walls  60 ′,  60 ″, and use the simple louvers of the first embodiment.  
         [0060]     In all of the above versions of the invention, when used for a lubricating wick intended for GE locomotive traction motors, the louver-shaped lubricant-reservoir pockets or splash cups may be, for example, approximately three inches in length. For an EMD locomotive traction motor, the width would be increased to match the increased width of the EMD wick. The length of the splash sleeve may be approximately 3.6 inches, while the material may be metallic or an elastomeric. Of course, the above-mentioned dimensions and material, as well as how the louver-shaped lubricant-reservoir pockets or splash cups are formed, have been only by way of example, and are not meant to be limiting.  
         [0061]     While specific embodiments of the invention have been shown and described, it is to be understood that numerous changes and modifications may be made therein without departing from the scope and spirit of the invention