HK1158585A - Railway coupler core structure for increased strength and fatigue life of resulting knuckle - Google Patents

Abstract

A finger core (10) for forming the front part of a knuckle (21) for a railcar, said finger core (10) comprising a single opening (18) to form a single rib (15) at the horizontal center line of the resulting knuckle (21).

Description

Railway coupler core structure for achieving increased strength and fatigue life of the resulting knuckle

Related application

This application claims priority to U.S. provisional application No. 61/055,924, filed on 23/5/2008, the disclosure of which is incorporated herein by reference in its entirety.

Technical Field

The present invention relates generally to the field of railway couplers and more particularly to a core for a front portion of a knuckle and a core for a rear portion of a knuckle.

Background

The front core of the knuckle is generally referred to as the finger core. The finger core is generally configured to create an internal cavity with thin ribs. These ribs have exhibited vulnerability to the loading environment as fatigue and/or hot tear cracking occurs. Fatigue cracking can increase over time and eventually lead to knuckle failure, which can lead to railcar separation. Internal or external fractures in the knuckle are the cause of the knuckle replacement, respectively.

The rear core of the knuckle is commonly referred to as the kidney core. The knuckle may sometimes break within this portion of the knuckle and this has proven to be a highly undesirable location for failure. Failure in this region of the knuckle can result in jamming of the knuckle within the coupler body and make the failed knuckle unusable, requiring replacement of the entire coupler assembly, which can be costly to repair.

There is a need to improve the strength and/or fatigue life in these areas of the knuckle while still allowing it to be a weak connection in the coupler system and fail under high load conditions.

Disclosure of Invention

In a first embodiment, a finger core for forming a front portion of a knuckle for a railcar is provided that includes a single opening to form a single rib at a horizontal centerline of the resulting knuckle.

In a second embodiment, a core for forming a rear portion of a knuckle for a railcar is provided that includes a kidney core section having maximized internal fillets and reduced polished shoulder portions and a pivot pin core section.

In a third embodiment, a set of cores for forming a knuckle for a railcar coupler having increased strength and/or fatigue life is provided, and the set of cores comprises: a finger core for forming a front portion of a knuckle of a railway car, the finger core including a single opening to form a single rib in the resulting knuckle; and a core for forming a rear portion of a knuckle of a railcar, the core including a kidney core section having maximized internal fillets and reduced polished shoulder portions and a pivot pin core section.

In a fourth embodiment, a railway coupler knuckle is provided having increased strength and fatigue life that includes a single thick rib in the knuckle.

Drawings

The system may be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views.

Fig. 1 is a perspective view of a knuckle.

Fig. 2 is a top plan view of the knuckle of fig. 1.

FIG. 3 is a cross-sectional view of the knuckle of FIG. 1 along line A-A from FIG. 2.

Fig. 4 is a side plan view of the knuckle of fig. 1.

FIG. 5 is a cross-sectional view of the knuckle of FIG. 1 along line B-B from FIG. 4.

Figure 6 is a side view of the finger and kidney cores prior to attachment.

Fig. 6a is a top view of the finger core and kidney core of fig. 6 in a set-up configuration.

Fig. 6b is a perspective view of the finger core and kidney core of fig. 6 a.

Figure 6c is a side view of the finger core and kidney core of figure 6 a.

Fig. 7 is a top view of the finger core and kidney core of fig. 6 a.

Fig. 8 is a side view of the finger core and kidney core of fig. 6 a.

Fig. 9 is a perspective view of the kidney core of fig. 6 a.

Figure 10 is a perspective view of the finger core of figure 6 a.

Figure 11 is a side view of the finger core and kidney core of figure 6 a.

Fig. 12 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 13 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 14 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 15 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 16 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 17 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 18 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 19 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 20 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 21 is a top view of the finger core and kidney core of fig. 6 a.

Fig. 22 is a top view of the finger core and kidney core of fig. 6 a.

Figure 23 is a side view of the finger core and kidney core of figure 6 a.

Figure 24 is a side view of the finger core and kidney core of figure 6 a.

Fig. 25 is a perspective view of the finger core and kidney core of fig. 6 a.

Figure 26 is a side view of the finger core and kidney core of figure 6 a.

Fig. 27 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 28 is a perspective view of the finger core and kidney core of fig. 6 a.

Figure 29 is a side view of the finger core and kidney core of figure 6 a.

Figure 30 is a perspective view of the finger core and kidney core of figure 6 a.

Fig. 31 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 32 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 33 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 34 is a bottom view of the finger core and kidney core of fig. 6 a.

Fig. 35 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 36 is a perspective view of the finger core and kidney core of fig. 6 a.

Figure 37 is a perspective view of the finger core and kidney core of figure 6 a.

Figure 38 is a side view of the finger core and kidney core of figure 6 a.

Figure 39 is a side view of the finger core and kidney core of figure 6 a.

Figure 40 is a side view of the finger core and kidney core of figure 6 a.

Figure 41 is a side view of the finger core and kidney core of figure 6 a.

Fig. 42 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 43 is a perspective view of the finger core and kidney core of fig. 6 a.

Fig. 44 is a top plan view of the finger core and kidney core of fig. 6 a.

Fig. 45 is a side plan view of the finger core and kidney core of fig. 6 a.

Fig. 46 is a side plan view of the finger core and kidney core of fig. 6 a.

FIG. 47 is a side plan view of the kidney core and C10 ridges of FIG. 6 a.

Fig. 48 is a side view of the finger core of fig. 6 a.

FIG. 49 is a side plan view of the knuckle of FIG. 1.

Fig. 50 is a cross-sectional view of fig. 49 taken along line C-C.

Fig. 51 is a top plan view of the knuckle of fig. 1.

FIG. 52 is a cross-sectional view of the interior of the knuckle of FIG. 1 along the line D-D of FIG. 51.

Detailed Description

It is an object of the present invention to improve the strength and fatigue life of a steering knuckle by utilizing two unique cores. The complete steering knuckle 12 is shown in fig. 1-5 for reference. Referring to fig. 6, the first dedicated core is a finger core 10 and the second dedicated core is a kidney core 12, which also includes a pivot pin core 13.

With respect to the front portion of the steering knuckle, the present invention utilizes the unique shape of the finger core 10, shown from different angles in fig. 6b, 6c, 10-20, 23-33, and 35-43. Figures 6-8 and 11-43 show the finger core 10 connected to the kidney core 12 to form the knuckle 21. Figure 6 shows the finger core 10 just about to be connected to the kidney core 12 by the interaction of the extensions 14 on the finger core 10 and the openings 16 on the pivot pin core 13. The finger core 10 is shown in isolation in fig. 9 and 10.

The complete steering knuckle 21 is shown in fig. 1 to 5. The finger core 10 forms the inner surfaces of the front face 26, nose 28, pulling face 30, heel 32 and flag hole 34 of the knuckle 21. The main section of the finger core 10 is preferably about 5.0 "wide by about 7.9" high with a 2.1 "wide by 4.9" high rib 15 in the center. (FIG. 6c and FIG. 45). The finger core 10 extends outward from the center to create a flag hole 24 of 1.3 "on both the top and bottom of the nose 28. The inner radius 36 of the finger core 10 is preferably smoothed to reduce stress and increase fatigue life. The finger core 10 also contains a flag hole core 72.

The finger core 10 is designed so that the opening 18 forms a single thick rib 15 at the horizontal centerline of the resulting knuckle to more effectively transfer the load to the pulling lugs of the knuckle and reduce the stress in the knuckle 21. As shown, the number of corners 19 has been reduced to four, and a radius larger than that present in the prior art is used in all four corners 19. Larger core fillets are also utilized. Exemplary dimensions of the opening 18 are shown in fig. 6c as being about 2.1 "wide and about 4.9" high, but it should be understood that other dimensions of such an opening are also possible.

These modified interactions result in less stress on the resulting rib 15, as can be seen in fig. 1 to 5, and in particular in the completed knuckle 21 shown in fig. 5, fig. 5 being a cross-sectional view along line B-B of fig. 4. Fig. 5 also provides a best view of the internal structure 23 formed by the kidney 12 and pivot pin 13 cores and finger core 10.

With respect to the posterior portion of the core, the present invention utilizes the unique shape of the kidney-shaped core 12. The internal fillets 20 and resulting wall thickness and profile of the core 12 are maximized. In addition, the size of the polishing shoulder portion 22 of the core has been reduced in order to maximize the wall thickness. Further, the shape of the core support 24 at the tail of the knuckle 21 has been optimized. The location of the aft support holes 25, the size, shape, and wall thickness of the holes, and the resulting internal fillets of these features have all been optimized to reduce stress concentrations while maintaining acceptable weight of the knuckle 21.

For simplicity, the measurements in this application have been rounded to one digit after the nearest decimal point, but they are often shown in the figures as being rounded to two or three digits after the decimal point.

As shown in FIG. 44, the pivot pin core 13 includes a section 42 of about 1.7 "diameter that forms the pivot pin hole 38 on each end of the hub 40. The holes 38 extend toward a larger central C-10 ridge formed by segments 44 drawn outward at about 2 degrees on the pivot pin core 13, as shown in fig. 8 and 9. The cross-section of the C-10 rib at the center plane of the knuckle is made up of a series of arc and parabolic sections. This irregular central cross-section 17 is approximately 2.5 "x 2.6". As shown in FIG. 46, the C-10 ridge 44 tapers back to the diameter of the pivot pin hole 38 at a distance of about 1.8 "on each side away from the center of the knuckle. As shown in FIG. 9, C-10 ridges 44 comprise oval shaped grooves 16 about 2.5 "high and about 1.0" wide for receiving finger core lugs 14. As shown in fig. 6 and 47, finger core lugs 14 are oval shaped posts 14 that are about 2.5 "high and about 1.0" wide and serve as a method for attaching a separate finger core 10 to pivot pin section 13 prior to casting. The inner radius of the central C-10 section is preferably smoothed to reduce stress and increase fatigue life.

Other regions are illustrated in which the kidney 12, pivot pin 13 and finger cores 10 have been modified to further reduce stress in the resulting knuckle. Unless otherwise specified, the measurements given for the adjusted radius in the present invention are given in inches (e.g., r.1 "or R1.2").

The kidney core 12 forms the inner surface of the knuckle 21 from behind the pivot pin hole 38 to the rear of the tail portion 46. This region is best illustrated in fig. 2 and 3. The kidney core 12 is part of the pivot pin core 13 and is attached by a section 48 that is about 2.1 "high by 0.7" wide. (FIG. 44 and FIG. 46). Polishing shoulder core 22 extends from this attachment point and is approximately 0.78 "in diameter and has an overall height of approximately 4.0". (FIG. 46). The polishing shoulder cores 22 each continue to taper outwardly into the main body of the kidney core 12. The main section of the kidney core 12 is about 3.6 "wide and about 1.0" thick. (FIG. 44 and FIG. 46). The modified dimensions of the kidney core 12 make the wall section thicker in the rear section of the knuckle 21 and improve stress and fatigue life.

The resulting wall thickness on the locking face 50 and just forward of the locking face 50 is about 1.4 ". (FIG. 50). The resulting wall thickness on the trailing stop side 52 of the kidney core 12 is about 1.2 ". (FIG. 46). The resulting wall thickness below the kidney core 12 is about 0.67 ". (FIG. 52). The resulting wall thickness above the kidney core 12 is about 0.5 ". (FIG. 52).

Behind the main section of the kidney core 12 is a top pulling lug core 56 that extends about 1.2 "above the top of the main section 54. (FIG. 46). Just behind the main section 54 and in front of the top pulling lug core 56, the width of the kidney core 12 begins to taper. The taper tapers to a final width of about 1.6 "and a height of 1.3" before extending out of the tail 46. (FIG. 44 and FIG. 46). The inner radius of the kidney core 12 section is preferably smoothed to reduce stress and increase fatigue life.

As described in the following paragraphs, many changes have been made to the specific radii of the finger and kidney cores. For clarity, the referenced sections are shaded in each figure. As previously mentioned, the following radius measurements are in inches.

The radius 58 where the section 42 forming the pivot pin hole 38 meets the section 44 forming the C-10 ridge is constant R1.0 "for both the top and bottom radii (FIG. 8). The radius 60 on the outer top and bottom portions of the finger core 10 opposite the flag hole core 72 is a constant R1.0 "(fig. 11). The radius 62 on the outer portion of the finger core 10 opposite the flag hole core 72 is a constant r.47 "(fig. 6 a). The radius 64 on the outer top and bottom of the finger core 10 is a constant r.47 "(fig. 6 and 12).

The radius 66 on the front and rear of the portion of the finger core 15 forming a single thick rib is a constant r.55 "(fig. 13 and 14). The top and bottom radii 68 on the portion of the finger core 10 near the pivot pin core 13 are a constant r.31 "(fig. 15 and 16). The radius 70 of the top and bottom flag hole cores 72 is a constant r.75 "(fig. 17). The radius 75 between the top and bottom flag hole cores 72 and the main cylinder 77 connecting the two has a constant r.50 "radius. The radius 74 joining the top and bottom flag hole cores 72 to the finger core 10 is a constant r.50 "(fig. 19).

The radius 76 of the base 78 forming the pulling lug core 36 in the kidney core 12 is a constant r.90 "(fig. 20). The radius 80 on each side of the kidney core 12 proximate the section 24 forming the rear core support hole is a constant R1.00 "(fig. 21 and 22). The radius 82 on the back of the top of the pulling lug core 36 on the kidney core 12 is a constant r.76 "(fig. 26). The radius 84 on the kidney core 12 near the throat 85 is a constant R4.00 "(fig. 7). The radius 86 on the throat side of the top pulling lug core 36 of the kidney core 12 is a constant R1.00 "(fig. 24). The radius 88 on the throat side of the top burnished shoulder core 22 of the kidney core 12 is a continuous variable radius fillet that begins at r.50 "and tapers to r.37 as it travels upward in the burnished shoulder core 22 (fig. 25). The radius 90 joining the rear of the pulling lug core 56 to the section forming the rear support hole 24 is a constant r.50 "(fig. 26). The radius 90 on the throat side behind the pulling lug core 36 of the kidney core 12 is a continuous variable radius fillet that starts at r.60 "and expands to r.64" as it travels outwardly to the section 24 forming the core support hole (fig. 27). The radius 94 on the top of the front of the pulling lug core 36 is a constant r.25 "(fig. 28).

The radius 96 on the bottom of the kidney core 12 just before pulling on the lug core 36 is a constant R1.00 "(fig. 29). The radius 98 on the throat side of the bottom buffing shoulder core 22 of the kidney core 12 is a variable radius fillet that starts at r.45 "near the rear core support hole formed by the lugs 24 and tapers to r.32" near the pulling lug core 36, then widens to r.50 "in the portion near the throat 85, then tapers to r.38" as it travels down the buffing shoulder core 22 (fig. 30). The bottom radius 100 on the aft stop side of the kidney core 12 is a continuous variable radius fillet that begins at r.45 "near the section 24 forming the aft core support hole and widens to r.60" as it travels toward the buffing shoulder core 22 (fig. 31). The apex radius 102 on the C-10 side of the kidney core 12 near the section 24 where the rear core support hole is formed is a constant r.64 "(fig. 32). The top radius 104 on the C-10 side of the kidney core 12 is a variable radius fillet that starts at r.25 "at the pulling lug core 36 and widens to r.80" as it travels toward the buffing shoulder core 22 (fig. 33). The radius 106 on the front on the C-10 side of the kidney core 12 near the pivot pin core 13 is a constant r.75 "(fig. 34). The radius 108 on the front of the top buffing shoulder core 22 on the C-10 side of the kidney core 12 near the pivot pin core 13 is a constant r.32 "(fig. 35). The radius 110 on the front of the bottom buffing shoulder core 36 on the C-10 side of the kidney core 12 near the pivot pin core 13 is a constant r.35 "(fig. 36). The radius 112 on the front of the top and bottom buffing shoulder cores 36 on the throat side of the kidney core 12 near the pivot pin core 13 is a constant r.75 "(fig. 37).

The fillets 114 where the legs 14 for attaching the finger core 10 to the pivot pin core 13 join the finger core 10 are a constant r.50 "(fig. 38 and 39). The fillet 116 joining the pivot pin core 13 to the kidney core 12 is a constant r.25 "(fig. 40 and 41).

The top burnished shoulder core 36 consists of a single raised surface 118 that starts on the flat surface of the kidney core 12 and travels upward through the burnished shoulder core 36 (fig. 42). The bottom burnished shoulder core 36 consists of a single raised surface 120 that starts on the flat surface of the kidney core 12 and runs down through the burnished shoulder core 36 (fig. 43).

It is intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention.

Claims (13)

1. A finger core for forming a front portion of a knuckle for a railcar, the finger core comprising a single opening to form a single rib at a horizontal centerline of the resulting knuckle.

2. The finger core of claim 1, wherein the single opening is about 2.1 "high and about 4.9" wide.

3. The finger core of claim 1, wherein the single opening has four corners.

4. The finger core of claim 1, wherein the corners are rounded.

5. The finger core of claim 3, wherein the corners of the single opening have an enlarged radius.

6. A core for forming a rear portion of a knuckle for a railcar, the core comprising a kidney core section having maximized internal fillets and reduced polished shoulder portions and a pivot pin core section.

7. A core set for forming a knuckle for a railcar coupler having increased strength and/or fatigue life, said core set comprising:

a finger core for forming a front portion of a knuckle of a railway car, the finger core including a single opening to form a single rib in the resulting knuckle; and a core for forming a rear portion of a knuckle of a railcar, the core including a kidney core section having maximized internal fillets and reduced polished shoulder portions and a pivot pin core section.

8. The set of cores of claim 6, wherein said single opening of said finger core is about 2.1 "high and about 4.9" wide.

9. The set of cores of claim 7, wherein said single rib is formed at a horizontal centerline of said resulting knuckle.

10. The set of cores of claim 6, wherein said single opening of said finger core has four rounded corners.

11. The core pack of claim 8 wherein the corners of the single opening have an enlarged radius.

12. A railway coupler knuckle having increased strength and fatigue life, said knuckle comprising a single thick rib in said knuckle.

13. The railway coupler of claim 12, wherein the single thick rib is located at a horizontal centerline of the knuckle.