US2960355A - Dust guard and oil seal - Google Patents

Description

N6v. I5, 1960 J. J. BAYERL DUST GUARD AND 011. SEAL Filed June 20, 1958 INVENTOR. c/JJf/H 5A YERL ATTORNEY United DUST GUARD AND 01L SEAL Joseph J. Bayerl, Wayne, N ..l., assiguor to United States Rubber Company, New York, N.Y., a corporation of New Jersey Filed June 20, 1958, Ser. No. 743,292

8 Claims. (Cl. 286-6) This invention relates to an improved dust guard and oil seal for insertion into the dust guard slot of a railroad car journal box.

Construction of present standard journal boxes calls for a relatively large opening with respect to the journal diameter at the rear of the box for ease of assembly, as well as proper functioning of the unit. This opening permits vertical and horizontal movement of the journal relative to the box of up to 1 /8" in vertical and up to in horizontal movement, depending upon the extent to which the journal and/or bearing are worn. It is necessary to seal this large opening regardless of journal position, under dynamic as well as static conditions.

The loss of oil, as well as its contamination, presents a costly maintenance and wheel-to-track slippage problem. Oil loss in transit is estimated to be nine parts for every one part actually used for lubrication. Cars which are turned upside down to be emptied lose practically all the oil in the reservoir of the journal box. Considerable maintenance is necessary to prevent hot boxes. Oil splash from box to wheel to track causes ineflicient engine operation, and contamination in the form of dust, dirt and Water for example, can cause oil film breakdown resulting in journal bearing damage. These are the problems which the present invention solves better than what has been done before by others.

It is known that dust guards and oil seals of wood, synthetic rubber sponge, foams and rubber-metal combinations are available. Wood dust guards do not prevent oil loss and have a very short life. All sponge or foam seals soak up oil which is squeezed out when the seal is under compression, and are also subject to damage by journal to box contact which occurs during transit, as are the rubber-metal combinations known to the inventor.

Accordingly, it is an object of this invention to provide an improved dust guard and oil seal so constructed and designed that it is efiective in preventing oil loss and contamination by foreign matter such as dust, dirt and water, regardless of journal position relative to the box, under both dynamic and static conditions; eliminates porous sections; prevents seal damage during installation, as well as that caused by journal to box contact; prevents oil loss through the rear of the box even when the car is turned over for automatic dumping; is easily inserted into and fits standard journal boxes; and prevents undue strain on the sealing elements.

Other objects and advantages of the invention will become apparent upon consideration of the following de tailed description, as well as the accompanying drawing wherein:

Fig. 1 is a vertical sectional view taken substantially along line 1-1 of Fig. 2, with portions broken away, and illustrating the rear portion of a standard journal box, the journal, and a preferred embodiment of the invention insented within the dust guard slot of the journal box;

Fig. 2 is a vertical sectional view taken substantially along line 2-2 of Fig. 1; and

Fig. 3 is a fragmentary enlargement of an upper portion of Fig. 2, illustrating in detail one of the sealing elements in the preferred embodiment of the invention.

Referring to the drawings, there is shown the rear portion of a standard, railroad car journal box 10; As is well known in the art, box 10 is a rough metal casing and is provided with an integral dust guard slot 11 at its rear. Slot 11, like box 10, is usually, substantially D-shaped in plan, and U-shaped in cross-section, and is provided with spaced front and rear walls 12 and 13 respectively, and an outer periphery 14. As will be apparent, walls 12 and 13 terminate in an enlarged, central opening for the rotatable journal 15, which is positioned within box 10 by the usual bearing 16 and wedge 17.

As has been pointed out above, it is necessary to seal this large opening regardless of the position of jotunal 15 relative to box 10. For this purpose, the improved dust guard and oil seal embodying the invention, is inserted within dust guard slot 11.

Basically, the inventive device is composed of a substantially rigid hollow casing 18 inserted in fixed position Within and closely conforming to the shape of dust guard slot 11, a curtain 19 slidably mounted within casing 18, and guide means composed of pin 21 on casing 18 and slide means 2 1 on curtain 19, for permitting curtain 19 to move eccentrically with journal 15 relative to casing 18, while preventing the curtain from rotating with the journal relative to the casing.

Casing 18 is preferably constructed from 21 gauge, cold rolled steel sheet metal, which is punched into a pair of substantially U-shaped plates having substantially oval openings. The outer edges of these plates are then bent, except at their tops, and welded together to form spaced front and rear walls 22 and 23 respectively, which walls form the enlarged central opening for journal 15 and terminate in flange 24.

Casing 18 is also provided with flexible means for sealing the interior of dust guard slot 11. This means is preferably composed of a rubber strip 25 which is coextensive with and bonded to flange 24. Strip 25 is provided with an integral coextensive lip 26 which projects angularly outwardly therefrom for a purpose to be described below. In fabricating strip 25 to flange 24, it is preferred that the strip and lip 26 be extruded cold to substantially the cross-sectional shape desired. Next, the desired length is wrapped around flange 24, which is embedded therein; then casing 18 and strip 25 are placed in a mold to produce the bond therebetween, and to cure the strip under heat and pressure.

Referring now to curtain '19, it is, like casing 18, preferably constructed from 21 gauge, cold rolled steel sheet metal, which is punched to form a substantially rigid member 27. The rigid member has a substantially oval outer periphery for a purpose to be described below, and a substantially circular inner periphery which forms a smaller opening for journal 15 than that formed in casing 18.

The curtain 19 is also provided with inner flexible means for sealing the outer periphery of journal 15 and with outer flexible means for sealing the opposed interior surfaces of casing walls 22 and 23. The inner flexible means is preferably composed of a rubber ring 28 Which is bonded to the inner periphery of annulus 2'7, and which has an integral coextensive lip 29 projecting angularly inwardly from the inner periphery of the rigid member and toward one side thereof, all for a purpose to be described below. The outer flexible means, which is shown most clearly in Fig. 3, is preferably composed of an oval rubber ring 30 which is bonded to the outer periphery of member 27. Ring 30 is provided with integral and coextensive front and rear lips 31 and 32 respectively, as well as integral and coextensive front and rear bumpers 33 and 34 respectively. Lips 31 and 32 project in substantially opposite directions from each side of the outer periphery of the rigid member and beyond bumpers 33 and 34 respectively. Lip 31 projects angularly inwardly, like lip 29, and lip 32 projects angularly outwardly, all for a purpose to be described below.

In fabricating the inner and outer sealing means on member 27, it is preferred that rings 28 and 30 be extruded cold to produce uncured strips having the desired cross-sectional shapes. Next, the strips are cut to the desired lengths and wrapped around the inner and outer peripheries of the member, which are embedded therein. Finally, member 27 and rings 28 and 30 are placed in a mold to produce the bond therebetween and to cure the rings under heat and pressure.

It is to be understood that the term rubber as used herein includes natural and synthetic rubber, as well as other suitable elastomers. The preferred material for strip 25, and rings 28 and 30 is a low compression set and heat resistant, butadiene-acrylonitrile compound, commercially sold under such trademarks as Paracril or Hycar," and having excellent oil and water resistant properties. In addition, ring 28 is impregnated with graphite to obtain a low coeflicient of friction, and thereby reduce heat build-up caused by the rotation of journal 15.

Referring now to the guide means, it is preferably composed of pin 20 on casing 18 and slide means 21 on curtain 19, as noted above. Slide means 21 preferably comprises spaced parallel lugs 35 projecting from the rear side of the central upper portion of member 27, between rings 28 and 30. Lugs 35 are located on either side of and extend substantially parallel to a vertical diametrical line of the inner periphery of member 27, for a purpose to be described below. Pin 20 projects axially inwardly from the central upper portion of rear wall 23 of casing 18 and into sliding engagement with lugs 35, and is located on a vertical diametrical line of the inner periphery of casing 18 and is axially spaced from the rear of member 27 for a purpose to be described below.

In fabricating lugs 35, they may be made integral with member 27, as by stamping during the formation of the member. However, it is preferred that lugs 35 be made separately from heavy gauge steel plate and then secured to member 27 by means of rivets 36, for greater strength. Likewise, in fabricating pin 20, it may be made integral with casing 18, as by stamping one of the plates forming rear wall 23. However, it is preferred that pin 20 be cut from cold rolled bar stock, forced through a hole in the plate which is to form the rear wall 23 of casing 18, and then welded in place, as shown, for greater strength.

In assembling curtain 19 in casing 18, the curtain is lowered down through the open top of the casing between walls 22 and 23, care being taken that lugs 35 are matched up with pin 20. This automatically assures that lips 29 and 31 on curtain 1? face in the same general direction as lip 26 on casing 18.

Next, the dust guard and oil seal is inserted into dust guard slot 11, care being taken that lugs 35 and pin 20 face the rear or wheel side of box 10. This automatically assures that the various sealing lips face in the proper directions with respect to the dust guard slot. The casing 18, which closely conforms to the shape of slot, is located in the proper fixed position therein merely by pushing the casing down until it seats firmly in the well, with lip 26 in firm engagement with the inner surface of the peripheral wall 14 of the slot. Depending upon the particular construction of walls 12 and 13, the lower inner periphery of casing 18 will then be either flush with or lie within the lower inner periphery of walls 12 and 13, as shown. In addition, the top of casing 18 will lie substantially below the top of dust guard slot 11.

At this point, a block of wood, W, is wedged into the top of dust guard slot 11 between walls 12 and 13, preferably down far enough to engage the top of casing 18 and thereby provide additional means for keeping the casing in place. Then, the block W and the tops of Walls 12 and 13 are covered over with a tarry substance (not shown) in order to prevent infiltration of foreign material such as dust and water, into the top of slot 11. This procedure is standard practice in the railroading industry and, as such, forms no part of the invention. However, it is important to note how well the invention fits in with such standard practice.

Next, box 10 is mounted in place over journal 15, and bearing 16, as well as wedge 17, are properly located, all in a manner well known in the art. Nevertheless, it is important to note that the enlarged opening in casing 18 provides ample clearance for passage of journal 15 and that curtain 19 is free to move up or down and/ or sideways with the journal relative to the box during this positioning step. Likewise, lip 29 on ring 28 is axially spaced from front casing wall 22 and front wall 12 of dust guard slot 11, so that it will not be wedged between the journal and these surfaces in the event of accidental contact therebetween.

Furthermore, as the box may be passed back and forth over the journal during this assembly operation, curtain 19 will readily give relative to casing 18. For example, should there be any drag between lip 29 and journal 15, the axial spacing between pin 20 and the rear face of an nulus 27, as well as that between bumpers 33, 34 and casing walls 22, 23 respectively, permits limited axial movement of the curtain relative to the casing, while bumpers 33, 34 cushion any impact caused by such movement.

In addition, the inner periphery of ring 28 cushions member 27 against impact from journal 15 while preventing undue flexing of lip 29. On the other hand, the outer periphery of oval ring 30 cushions the member against possible impact with flange 24 on casing 18. In this connection, it is to be noted that the radial spacing between the lower portion of oval ring 30 and adjacent flange 24 is always at least equal to or more than the spacing between the lower portion of journal 15 and the adjacent inner peripheries of dust guard slot walls 12 and 13, so that these walls will absorb the brunt of any contact with the journal, rather than the curtain or the casing.

As will be apparent, the advantageous characteristics noted above are equally effective during disassembly of the box from the journal. Likewise, such characteristics are effective during the operation of the device, which will now be described.

Under the usual transit conditions, journal 15 rotates relative to bearing 16, moves longitudinally thereof, as, for example when the car rounds a curve, and also vibrates vertically relative thereto, as in passing over switches etc. In addition, in starting or stopping a trainload of cars, in adding or removing cars from a train, and in the well known humping operations, the journal is often suddenly jarred out of engagement with bearing 16 and into contact with the lower inner edges of dust guard slot walls 12 and 13. This latter movement is down and to the right or left as viewed in Fig. 1.

Regardless of the position of journal 15, even when the car is overturned for dumping its contents, the sealing elements of the invention are effective. The inner periphery of lip 29 on ring 28 is slightly smaller than journal 15 to insure a substantially hermetic seal therewith, and the lip extends angularly inwardly toward the front wall 12 of dust guard slot 11 to obtain the desired wiping action, thereby preventing any lubricating oil on the journal from migrating back through the rear of box 10. Should the journal move toward the rear of the box, lip 29 will wipe the surface moving therethrough clean because of the compression between the inner surface of the lip against the journal, which compression is increased by the build-up of oil on the outer surface of the lip. At the same time, lip 29 offers little resistance to journal movement toward the front of the box because of its flexibility, but the compression therebetween is, neverthe less, more than adequate to prevent infiltration of foreign material such as dust, dirt and water, from the rear of the box.

The angle between the inner surface of lip 29 and journal plays an important part in this function, and is a practical application of a well known principle. In the sealing art, it is generally accepted that the acute angle between the surface of the sealing element and the surface to be sealed, should be about 45 for optimum results. Thus, in the present invention, this principle is applied not only to lip 29, but lips 31, 32 and lip 26, as well.

As journal 15 moves vertically and/or horizontally with respect to bearing 16 and box 10, curtain 19' readily moves along with the journal relative to casing 18. This requires the maintenance of a dynamic seal between the curtain and easing, as opposed to the static seals between lip 29 and the journal, as well as lip 26 and flange 24. It is to be noted at this point, that the seal between lip 29 and journal 15 is basically a static seal, because the surface area to be sealed does no more than merely change its position with journal rotation, and the relative axial movement between the journal and the lip is quite limited. On the other hand, the relative vertical and/ or horizontal movement between lips 31, 32 and casing walls 22, 23 respectively, is substantially and constantly changing. Furthermore, it is in the area between casing 18 and curtain 19, that proper sealing action is critical in order to prevent substantial loss of oil through the rear of the box.

To this end, the lips 31, 32 on ring 30* are slightly sprung in compression against the smooth inner surfaces of casing walls 22, 23 respectively, in order to obtain substantially hermetic sealing engagement therewith during the various vertical and/ or horizontal movements of journal 15. For simplicity of illustration, assume that the journal is merely reciprocating vertically, and that the oil in the bottom of the journal box splashes over front wall 12 and down into dust guard slot 11.

On the down stroke of journal 15 and curtain 19, lip 31, which projects angularly inwardly toward the front of slot 11 will readily flex to permit any oil, which might have leaked intothe space between the outer periphery of ring 30 and flange 24 of casing 18, to pass upwardly between the lip and easing wall 22. At the same time, lip 32, which projects angularly outwardly toward the rear of slot 11, will wipe wall 23 clean and force the oil between lip 31 and wall 22. On the up stroke of curtain 19, lip 31 will perform the wiping operation on wall 22 to force the oil back into the box, while lip 32 will readily flex and offer little resistance to the upward movement of the curtain. Nevertheless, the compression of lip 32 against wall 23 will be more than adequate to prevent infiltration of foreign material from the rear of the box.

Actually, casing 18 and curtain 19' function somewhat like a pressure diflferential pump. On the down stroke of the curtain, the increased pressure on the oil in the decreasing space between the outer periphery of ring 30 and flange 24 of the casing builds up a fluid head against the outer peripheral surface of lip 32 to increase the seal with wall 23 and forces the oil past the downwardly moving lip 31. However, on the up stroke, the pressure on the oil in this now increasing space is reduced, and the fluid head is built up against the inner peripheral surface of upwardly moving lip 31. This increases the seal with wall 22, and forces the oil back over the wall and into box 10.

As will be apparent, when journal 15 is jarred out of engagement with hearing 16, and moves downwardly both in a vertical and horizontal direction, this pumping-like action between casing 18 and curtain 19 is effective. For example, should the journal suddenly move downward and to the right, as viewed in Fig. 1, any oil which may have been splashed up and to the left between the curtain and easing will be forced back into the box by the wiping action of lip 31, which (like lip 32) extends all the way around the curtain within the casing. Likewise, when the journal returns to its normal position, this same lip 31 will wipe the oil, which has been forced past it from the lower right hand side, back into the box. Moreover, even when the car is turned upside down, this pumping action is effective. However, in this position the block of wood W, will in addition to flange 24, define the closed space between ring 30 and casing 18, as seen in both Figs. 1 and 2.

Referring once again to Fig. 3, it will be noted that sealing lips 31 and 32 on ring 30 are sufiiciently long and sprung in compression against walls 22 and 23 respectively, that they will not lose sealing contact in the event bumpers 33 and 34 are suddenly forced against the walls. As will be evident, this condition could readily occur if journal 15' suddenly moved longitudinally relative to box 10'. However, no loss in the desired sealing function will be suffered, beacuse of this construction.

Referring back to Figs. 1 and 2, the guide means comprising pin 20 and slide means 21 perform a very important function in permitting curtain 19 to move with journal 15 in the various vertical, horizontal and longitudinal movements noted above. However, it is essential that the curtain be prevented from rotating any substantial amount with the journal.

In permitting movement of curtain 19 with journal 15, lugs 35 slidably engage pin 20 for both horizontal and vertical movement relative thereto, and pin 20 serves as a pivot about which the lugs can oscillate as well. Thus, curtain 19 is free to follow the various eccentric movements of the journal relative to the box. At the same time, curtain 19 is not permitted to rotate with journal 15, thereby preventing any damage to the dust guard and oil seal.

As will be apparent, the outer periphery of curtain 19 is substantially oval to provide complete sealing engagement and adequate space between it and the substantially U-shaped outer periphery of casing 18, for the necessary relative movement therebetween. If curtain 19 were permitted to rotate with journal 15 relative to casing 18 to any substantial degree, it would quickly become jammed therein, thereby destroying the effectiveness of the inventive device, and subjecting it to serious damage.

In regard to the seal between casing 18 and dust guard slot 11, this is provided by rubber strip 25 and lip 26. In view of the relatively rough interior surfaces of slot 11, which is cast integrally with box 10, the metal to metal contact between the casing walls and the slot walls allows some oil to leak out from the box and down between adjacent walls 12 and 22. However, lip 26 is compressed against the inner surface of well periphery 14 to provide a substantially hermetic seal therewith. Furthermore, the oil builds up a static head on the inner peripheral surface of the lip 26, which is especially designed to project angularly outwardly toward the front of the well, and thus the seal between lip 26 and the inner surface of periphery 14 is enhanced to prevent any substantial leakage of oil past it, or infiltration of foreign material from the rear of box 10. As with lips 29, 31 and 32, noted above, the acute angle between lip 26 and periphery 14 is approximately 45 for optimum sealing engagement therebetween.

It will now be evident that the above described in vention accomplishes all of the objects previously described, and more. While a preferred embodiment of the invention has been described and illustrated, it is to be understood that various changes and modifications 7 may be made therein by those skilled in the art without exceeding the scope of this invention, as defined in the appended claims.

Having thus described my invention, what I claim and desire to protect by Letters Patent is:

1. A dust guard and oil seal curtain for a railway car journal box, comprising a substantially rigid plate member having a central opening for accommodating a journal, and a pair of sealing rings attached to said plate member at the inner and outer peripheral edges thereof, respectively, the inner sealing ring being provided with a journal sealing lip extending angularly radially inwardly therefrom, and the outer sea-ling ring being provided with a first journal box dust guard slot sealing lip extending angularly radially outwardly therefrom on one side and a second journal box dust guard slot sealing lip extending angularly radially inwardly therefrom on the other side.

2. A dust guard and oil seal curtain for a railway car journal box, comprising a substantially rigid plate member having a central opening for accommodating a journal, and a pair of sealing rings attached to said plate member at the inner and outer peripheral edges thereof, respectively, the inner sealing ring being provided with a journal sealing lip extending angularly radially inwardly therefrom, and the outer sealing ring being provided with a first journal box dust guard slot sealing lip extending angularly radially outwardly therefrom on one side and a second journal box dust guard slot sealing lip extending angularly radially inwardly therefrom on the other side, said outer sealing ring being further provided with a pair of oppositely laterally projecting bumper ridges.

3. A dust guard and oil seal curtain for a railway car journal box, comprising a substantially rigid plate member having a central opening for accommodating a journal, and a pair of flexible sealing rings attached to said plate member at the inner and outer peripheral edges thereof, respectively, the inner sealing ring being provided, at the radially innermost peripheral edge thereof and on the side thereof which is to face said journal box, with a coextensive journal sealing lip extending angularly radially inwardly therefrom, and the outer sealing ring being provided at the radially outermost peripheral edges thereof and on opposite sides with first and second coextensive journal box dust guard slot sealing lips, one of said last-named lips extending angularly radially outwardly of said outer sealing ring, the other of said last-named sealing lips extending angularly radially inwardly of said outer sealing ring, said outer sealing ring being further provided with a pair of oppositely laterally projecting bumper ridges at the ra dially innermost peripheral edges thereof.

4. A dust guard and oil seal curtain according to claim 3, further comprising guide means affixed to said rigid plate member at one of the faces thereof and adapted to coact with a corresponding part fixedly arranged in said journal box for inhibiting rotary movement of said plate member while permitting vertical, horizontal and combined vertical/horizontal movements thereof.

5. A dust guard and oil seal for a railway car journal box, comprising a substantially rigid plate member having a central opening for accommodating a journal, the inner peripheral edge of said plate member defining the boundary of said opening being substantially circular, the outer peripheral edge of said plate member being substantially oval, and a pair of flexible sealing rings bonded to said plate member at said inner and outer peripheral edges thereof, respectively, the inner sealing ring being provided, at the radially innermost peripheral edge thereof and on the side thereof which is to face said journal box, with a coextensive journal sealing lip extending angularly radially inwardly therefrom, and the outer sealing ring being provided at the radially outermost peripheral edges thereof with first and second coextensive journal box dust guard slot sealing lips, said first sealing lip extending angularly radially outwardly of said outer sealing ring and being disposed on the side of the latter which is to face away from said journal box, said second sealing lip extending angularly radially inwardly of said outer sealing ring and being disposed on the side of the latter which is to face said journal box, said outer sealing ring being further provided at the opposite radially innermost peripheral edges thereof with a pair of bumper ledges, both said ledges projecting laterally from said outer sealing ring and coaxially with said central opening of said rigid plate member.

6. A dust guard and oil seal according to claim 5, further comprising a pair of spaced, parallel, vertically disposed guide bars fixedly connected with said rigid plate member adjacent the top thereof intermediate said inner and outer sealing rings and on the side of said plate member which is to face away from said journal box, said guide bars being adapted to receive in the space therebetween a horizontal pin in said journal box for inhibiting rotary movement of said plate member with said journal while permitting vertical, horizontal and combined vertical/horizontal movements of said plate member.

7. A dust guard and oil seal for a railway car journal box having a dust guard slot, comprising a substantially rigid hollow casing open at the top and closed over the entire remainder of its periphery, said casing being adapted to be immovably mounted in said dust guard slot, the front and rear walls of said casing being provided with respective central openings for accommodating a journal, 21 curtain-constituting substantially rigid plate member slidably arranged within said casing, said plate member being provided with a central opening for accommodating said journal, a pair of sealing rings attached to said plate member at the inner and outer peripheral edges thereof, respectively, the inner sealing ring being provided with a journal sealing lip extending angu larly radially inwardly therefrom, the outer sealing ring being provided with first and second sealing lips extending therefrom on opposite sides into engagement with the associated Walls of said casing, said first sealing lip extending angularly radially outwardly and said second sealing lip extending angularly radially inwardly such that a pump-like action is developed across the outer sealing ring upon movement of the plate member Within the casing.

8. A dust guard and oil seal according to claim 7, further comprising a flexible sealing member attached to the exterior of said casing over the entire closed periphery thereof, said sealing member being provided with a sealing lip extending angularly therefrom and adapted to engage the inner peripheral surface of said dust guard slot when said casing is positioned therein.

- References Cited in the file of this patent UNITED STATES PATENTS 2,103,555 Rowe Dec. 28, 1937 2,186,537 Salisbury Jan. 9, 1940 2,487,669 Pattullo et a1. NOV. 8, 1949 2,668,067 Fitzsimmons Feb. 2, 1954 2,742,306 Kelso et a1. Apr. 17, 1956

Images