US3013822A - Journal dust guard - Google Patents

Description

Dec. 19,

H. W. FROST, JR

JOURNAL DUST GUARD Filed May 11, 1959 FIG. 8

INVENTOR. HARRY W. FROST JR.

BY m

ATTORNEY United States Patent 3,013,822 JG'URNAL DUST GUARD Harry W. Frost, In, Grosse Pointe, Mich. (2920 E. Jefferson Ave., Detroit 7, Mich.) Filed May 11, 1959, Ser. No. 812,248 6 Claims. (Cl. 286-6) This invention relates to a journal dust guard and more particularly to a novel and inventive dust guard for railroad journals made of a relatively thin flexible membrane material and having outer side and bottom flanges making pressure bearing contact with the inner wall surface of the dust guard cavity.

The invention of this application is a continuation in part of my earlier filed patent application Serial No. 705,590 filed December 27, 1957 and now abandoned for Journal Dust Guard.

The dust guard of this invention is designed for use in the dust guard cavity of a railroad car truck journal box. The cavity is located inwardly of the journal chamber, having parallel vertical side walls, a rounded bottom wall blending into the two side walls, and a horizontal top opening through which the dust guard is introduced into and removed from the cavity. The dust guard of this invention, in both of its forms, is provided with a flat membrane body, and is formed of a material which is relatively stifl? yet flexible in character. Using the point of intersection of the body plane and the axis of the dust guard as the point of reference, side and bottom flanges extend from the membrane body at an angle greater than 90 to the plane of the body, a top flange at an angle of 90 to the body plane and disconnected from the adjacent side flanges, and an inner central circular axle bearing flange at an angle of less than 90 to the body plane. When the dust guard is introduced into the dust guard cavity, the side and bottom flanges make pressure bearing contact with the side and bottom wall surfaces of the cavity, the side and bottom flanges being under restriction against their normal expansion. The top flange may be surmounted by a strip of oakum, or other closure material, secured in sealed relationship by a coating of asphalt, tar or other suitable material thereover at thetop opening of the dust guard cavity.

The dust guard is fabricated of the newly developed and available polypropylene plastic material which provides many useful advantages in applications where acidic, oily and corrosive materials are present. In addition, the material has a high resistance to shock, vibration forces and normal frictional wear, as well as good resistance to thermal deterioration at such temperatures as are involved in the present application. Other materials are described in the description given below.

The advantages of the dust guard of this invention, in both of its forms, appear to include relatively lower production costs, ease of fabrication, simplicity of design, eirective control of oil flow and exclusion of roadbed dirt and grime, use of an unbreakable material, and less maintenance and replacement of dust guards by maintenance crews.

A primary object of the invention is the provision of a relatively flexible flat membrane body in a journal dust guard having angled outwardly extending side and bottom flanges, a top flange disconnected from the adjacent side flanges, and a central circular flange tapering inwardly to a bearing position on the axle. Another object is the provision of outer edge flanges which may be directed in the same direction as the central bearing flange, or oppositely directed. Yet another object is to provide a dust guard whose angled outer side and bottom flanges have their edges making pressure bearing contact with the inner wall surfaces of the dust guard cavity.

or 3,013,822 Patented Dec. 19, 1961 These and other objects of the invention and features of construction will become more apparent from the description of the invention given below in which the terms employed are used for purposes of description only and not of limitation.

Referring now to the drawing annexed hereto and forming an integral part of this specification,

FIG. 1 is a perspective view of the dust guard of this invention.

FIGS. 2 and 7 are perspective views of slightly modified dust guards.

FIG. 3 is a vertical sectional view showing the dust guard of FIG. 1 in position.

FIG. 4 is a transverse vertical sectional view taken substantially on the line 44 of FIG. 3.

FIG. 5 is a horizontal sectional view taken on the line 55 of FIG. 3.

FIG. 6 is a vertical sectional view, similar to FIG. 3, showing the dust guard of FIG. 2 in position.

FIG. 8 is a horizontal sectional view taken on the line 8-8 of FIG. 6.

FIG. 9 is a transverse vertical sectional view, similar to FIG. 4, showing the dust guard of FIG. 7 in position.

As shown in FIGS. 1, 3, 4 and 5, the journaldust guard 10 is integrally formed of a relatively stifl yet flexible material and comprises a flat membrane body portion 12, an inner central circular tapering axle bearing flange l4, outwardly flared side flanges 16, 16, a rounded outwardly flared bottom flange 18, and a top flange 20 disconnected from the adjacent side flanges and disposed at right angles to the plane of the body 12. The central flange 14 is provided with an axle bearing edge 15 making contact with the axle, but being spaced slightly from the axle. The diameter of the bearing edge 15 is slightly larger than the diameter of the axle in the area of the dust guard cavity.

The axle 22 upon which the dust guard is mounted comprises a wheel hub portion 24, the dust guard hub portion 26, and the bearing journal 28. The hub portion 26 is provided with a sharp leading edge26a.

The journal box 30 in which the dust guard is positioned comprises in part the dust guard cavity or chamber 32 formed by an outer wall 34 having an axle opening 36, an inner Wall 38 having an axle opening 40, and a journal housing 42 outwardly of the dust guard cavity. The side and bottom inner wall surfaces of thedust guard cavity 32 are identified by the common reference numeral 44.

"the dust guard It) is made of a plastic material known and identified as polypropylene. It may also be made of other materials having satisfactory characteristics suitable to the conditions involved in the application use here described. For instance, a sheet material made of a linen or textile core over-laid on each side with an oil-impervious material that would not materially. limit or restrict flexure of the core material, a fibrous suitablycoated sheet material, a rubber sheet material having an oil-resistant and impervious character, nylon sheeting.

The excellent thermal properties in both the high and low ranges, and the low water absorption characteristics of polypropylene make this material most desirable for use in the journal dust guard of this invention.

As shown particularly in FIGS. 1, 3, 4 and 5,1115

dust guard 10 is placed in the dust guard cavity 32 so that the side and bottom flanges 16, 16 and 18 make a line contact with the inner side and bottom wall surfaces 44. The free distance, before insertion, across the face of the dust guard between the outer edges of side flanges 16, 16 is slightly greater than the distance between the side wall inner surfaces 44 in the cavity 32, so that the side and bottom flanges 16, 16 and 18 are put under some compression when the guard is placed in the cavity 32. This relationship between the guard and the cavity tends to hold the guard in close bearing relationship in the cavity and to restrict transmission of deleterious materials into the journal housing 42. The inner central circular axle bearing flange 14 of guard 10 is tapered in the same direction as the side, top and bottom flanges, the tapering flange being substantial in length to provide the means of re-entry by the axle portion 26 for normal rotation within edge 15.

Under normal road riding conditions, the axle hub portion 26 will not ordinarily shift in an axial direction to any great extent, i.e. it will not ordinarily move out of the area of the dust guard cavity 32. However, under exceptional conditions or circumstances, and particularly during the testing of dust guards, the axles are caused to shift axially as much as two inches so that the leading edge 26a of the dust guard hub portion 26 will move inwardly, i.e. to the right in FIGS. 3 and 5, to a position beyond the plane of the dust guard and the cavity 32.

So long as the axle portion 26 remains in concentric alignment with a dust guard under test, it will move axially into and out of the center bearing of the guard without damage, but should the axle be displaced both laterally and axially, upon forward thrust toward the dust guard the sharp leading edge 26a will be forced against the side of the dust guard and cause severe damage or destruction resulting in an ineffective guard and possible consequent damage to the journal 28 and the car itself. Therefore, the provision of a tapering central axle bearing inner flange in the instant dust guards here disclosed tends to avoid such damage and loss by providing a very large lead for the axle hub portion 26 should the axle be laterally as well as axially displaced beyond the plane of the dust guard.

In addition, the angularity of the side and bottom flanges 16, 16 and 18 is such that lateral shift of the dust guard 10, within reasonable limits, will not greatly disturb the bearing contact of these flange edges with the inner cavity wall surfaces 44.

The thickness of the dust guard 10, and of the modified dust guards described more specifically below, is less than the inside width of the cavity 32, i.e. the distance between the walls 34 and 38, so that the guard 10 will slip smoothly into the cavity 32 without binding and will permit simple flexure of flanges 16, 16 and 18. Thus, when lateral displacement of the axle portion 26 occurs, the guard membrane body 12 will bear firmly against wall 34 supporting the membrane body edge 39 bending into the central flange 14 so that this edge acts as a pivot for the flange during the period of flexure.

When the dust guard 10 is in position about the axle hub portion 26, the top flange 20 is positioned horizontally and normal to the plane of the cavity 32. To seal the dust guard in place, a piece of oakum 46 is packed into the top opening of the cavity 32, seated upon the top flange 20, and there sealed in place with a suitable tar or sealing adhesive.

The diametric relationship of the central flange edge 15 and the axle portion 26 is such that the flange edge does not become an oil seal for the axle. The edge 15 makes an intermittent contact with the axle 26, not a permanent oil seal contact therewith. The edge 15 makes and loses contact with the axle portion 26 in the latters rotation, at particular edge portions. The results of tests in railroad testing equipment have shown that the dust guard edge 15 need not be a close fitting oil seal edge in order to serve as an oil repellent element. Tests with the dust guard 10 indicate that the inner central tapering flange bearing edge 15 serves effectively as a wiping edge for the axle portion 26 to resist oil transfer from the journal and not as a seal for the axle. It is believed that a contributing functional factor present in the instant invention provides such an advantage.

The central flange 14 below the horizontal diameter line taken through its axis, as in FIG. 4, is concentric with the side and bottom flanges 16, 16 and 18 and just slightly spaced from them. When the axle shifts laterally or radially the central flange 14 and the adjacent side or bottom flange tend to come together, as when the thumb and first (index) finger are brought together. This action may be described as a pumping action, the closing flanges providing the compressive elements or members that force fluid (oil) from the area between the flanges. The pumping action is directed toward the journal housing 42, and oil which may have entered the cavity 32 and lies between the flanges appears to be pumped out of the cavity.

A simple modification of the dust guard 10 is that shown in FIGS. 2, 6 and 8 in which the integrally formed dust guard 50, made of the same material as is used for the guard 10, comprises a flat membrane body 52, an inner central circular tapering axle bearing flange 54 provided with an axle bearing edge 55, outwardly flared side flanges 56, 56, a rounded outwardly flared bottom flange 58, and a top flange 60 disconnected from the adjacent side flanges and disposed at right angles to the plane of the body 52. The body portion is provided with a single reverse bend 62 concentrically about the inner central bearing flange 54, so that the direction of the flange 54 is opposite to that of the outer edge side, top and bottom flanges 56, 56, 60 and 58, respectively.

In installing the dust guard 50 in the cavity 32, the central axle bearing flange 54 is directed toward the journal housing 42, as in the case of the dust guard 10. However, the outer side, top and bottom flanges 56, 60 and 58, respectively, are directed toward the wheel side of the journal box, i.e. toward the axle portion 24. The oakum strip 46 is applied as before upon the top flange 6t sealing the dust guard 50 in the cavity 32. The side and bottom flanges 56, 56 and 58 bear firmly upon the inner cavity wall surfaces 44, as in the case of the dust guard 10, to restrict by-pass of deleterious matter to the journal chamber 42.

A second modification of the dust guard 10 is that shown in FIGS. 7 and 9, in which the guard comprises a flat membrane body 72, an inner central circular tapering axle bearing flange 74 provided with an axle bearing edge 75, outwardly flared side flanges 76, 76, a rounded outwardly flared bottom flange 78, and a top flange disconnected from the adjacent side flanges and having extended ends 82, 82 overlying the side flanges. The top flange 80 is also disposed at an angle greater than to the plane of the membrane body 72. As in the case of the dust guard 10, the body portion 72 is provided with a single bend into the central axle bearing flange 74 so that all of the flanges of the guard 70 are disposed in the same direction. The dust guard 70 is substantially identical with guard 10 except for the top flange 80 which is longer and is disposed at an angle to the plane of the body portion 72 greater than 90. The top flange 80 is also wider than the top flange 20 of guard 10. This is possible because of the angle at which the top flange 80 is disposed.

In FIG. 9, it will be observed that the top flange ends 82, 82 are forced upwardly as the guard 70 is passed into the cavity 32. As the side flanges 76 are compressed inwardly, the top flange ends 82, 82 which extend thereover are caused to turn upwardly as the distance across the cavity 32 from side wall surface 44 to side wall surface 44 is less than the length of the top flange 80. The top flange then serves as a closure under compression for the cavity 32, and the need for a separate closure such as the strip of oakum 46 is eliminated.

It appears, as the result of testing, that close bearing contact of the side and bottom flanges with the cavity wall surfaces 44 is of major importance in dust guard construction. The instant construction, employing outwardly flaring flanged edges, provides a simple means to accomplish this function. The relationship which the side and bottom flanges bear to the inner wall surfaces 44 of the dust guard cavity, above described, provides the maintenance of an effective closure about the axle. Because the top flange of the dust guards 10, St) or 71} is cut from or disconnected from the side flanges, the latter are free to move laterally inwardly or outwardly without restriction by the top flange. Thus, should the axle shift upwardly as well as laterally, the tapering circular central inner bearing flange will flex at the membrane body, or if downwardly at the bottom flange, to provide full flexing control in the cavity.

Having described the invention in its simplest terms, the features of construction may be changed and varied in greater or lesser degree without departing from the essence of the invention as defined in the appended claims.

I claim:

1. In a dust guard for use with an axle in a journal dust guard cavity, a relatively stifl yet flexible flat membrane body of substantially uniform thickness throughout, said body having outwardly angularly extending integrally formed and conjoined side and bottom flanges, said flanges projecting from said body at an angle thereto of more than 90 in their free state prior to insertion in said dust guard cavity, said side and bottom flanges making a line contact with the side and bottom walls of said dust guard cavity when inserted thereinto, the distance across said side flanges in their free state being greater than the distance between said side walls of said dust guard cavity whereby said side flanges are caused to flex inwardly when in contact with said side walls, an inner central circular tapering flange integrally formed with said body terminating in an annular axle bearing edge, said body further having a top flange disconnected from the adjacent said side flanges whereby said side flanges are permitted to flex against said cavity side walls free of interference by said top flange, and projecting from said body on the same side thereof as said side flanges, said inner central tapering flange being designed for use with said axle so that said latter flange is directed toward the digital end of said axle, said side, bottom, and inner central tapering flanges being capable of flexing under compressive forces exerted by said axle when in motion, said side flanges maintaining line contact with said side walls when flexed under said compressive forces, and said inner central tapering flange being of a diameter and of an angle such that upon lateral and axial movement of said axle said inner central tapering flange provides a lead for said axle into the opening defined by said annular axle bearing edge without destructive elfect upon said dust guard.

2. The construction defined in claim 1, and in which the outer edges of said side, bottom, and inner central tapering flanges terminate substantially in a plane.

3. The construction defined in claim 2, and in which said body lies substantially in a plane parallel to said plane in which said outer edges substantially terminate.

4. The construction defined in claim 1, and in which said top flange is disposed in a plane substantially normal to the plane of said membrane body.

5. The construction defined in claim 1, and in which said top flange is disposed in a plane greater than to the plane of said membrane body, said top flange having ends extending outwardly beyond the sides of said body and over said side flanges.

6. The construction defined in claim 1, and in which said top, side and bottom flanges are so disposed that they project from said body in one direction, and said inner central tapering flange projects from said body in the opposite direction.

References Cited in the file of this patent UNITED STATES PATENTS 1,250,138 Burnett Dec. 18, 1917 2,668,067 Fitzsimrnons Feb. 2, 1954 2,692,783 Foss Oct. 26, 1954 2,858,148 Klingler Oct. 28, 1958 2,895,749 Sale July 21, 1959

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