US 2970347 A
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Description (OCR text may contain errors)
Feb. 7, 1961 c, F, MASSOPUST 2,970,347
HATCH PLUGS Filed May 16, 1957 ,5b a k?! 24 24 U y 4 0dr/ E Massopus/ 1 tangularhatch opening A13. i
. nited StatesA Patent'.
HATCH PLUGS Carl F. Massopust, Highland Park, lll., assignorto General AmericanTransportation Corporation, Chicago, Ill., a corporation of New York Filed May 16, 1951, ser. No. 659,619 1 claim. (ci. zo-as) The present invention relates to hatch plugs, or the like.
Itis a general object of 'theinventionto provide a 4hatch plug for a railway refrigerator car, or lthe like, that is of limproved construction having an exceedingly low coeicient of heat transfer and that is of strong and integral construction.
Another object of the invention is to providea hatch plug of improved composite construction that is ex-l ceedingly strong, although of very light weight, and having a very low coeflicient of heat transfer.
. Afurther object of the invention is to provide `annimproved composite hatch rplug, Awherein a unitary and integral construction is provided thatfinvolve's-a layer of synthetic organic resin 'that is molded in situ vwith respect ,to the other elements thereof. 1
A still further object of -the invention is toprovid'e 'Y an improved hatch plug thatinvolves a foamed layer of .polyurethane bonding together the other elements fof the v hatch Aplug that are also formed of rigid molded structure and of plasticmaterial.v v .Further features 4of the'invention pertain lto the particular arrangement of the elements of the hatch plug,
whereby the above-outlined andadditional operating fea- .tures thereof are attained. f f
The invention, both as to its.organization and method of operation, together with further objects 'and advanf tages thereof, will best be understood by reference to the following specification taken in Vconnection with the accompanying drawing, `in which:
Figure l is a fragmentaryplan view of a portion of the roof sheet of a railwayfrefrigerator carr'provided` 2,970,347 lgatejnted 7, 191611 forced with glass fibers, such, for example, as a 'suitable polyester; and specifically the sections 15 and 16 may be molded from a suitable polyester resin reinforced with glass bersand having the usual high impact strength.
The inner or' lower section 16 has a substantially dishlike or pan-like configuration that is substantially'rectangular in plan and-includes a bottomy wall 16a, an upwardly and outwardly directed marginalor boundary wall 16b, and anupwardly and outwardly directed and flared boundary rim 'or'ange' 16e; whereby the section VV16 is ofone-piece molded integral construction. The outer orupper section 15v has a substantiallyinverted dish-like configuration thatis substantially rectangular in plan and includes a top wall y15a and 'a' downwardly and outwardly directed and ared boundary` rim or flange 15b; whereby the section 15 is of one-piece molded integral construction.
Suitable flutes or ribs, not shown, may be produced in the sections 15 and 16 in a well-known manner incident to molding thereof forthe purpose of'lending additional stiffness and rigidity thereto.
The upper and lower sections 15 and 1-6 are arranged in assembled relation, whereby a substantial cavity was initially formed therebetween; which cavity issubstantially completely filled with a self-supporting heat-insulating body arranged between the sections 15 and 16 and intimately bonded thereto. The body mentioned `includes a central core element 17 and a ysurrounding and embeddingshell section 18. vMore particularly, the core section '17 is formed essentially of synthetic organi@ resin of cellular structure and having avhighcompressivc strength, a high tensilestrength and a high4 impact strength; and preferably the core 17 comprises aprej formed slab or block of material of rigid cellular structure, such, forexample, asa suitable foamed synthetic organic-resin, such as foamed polystyrene. Moreparticularly, the shell section 18 is formed essentially of synthetic o-rganic resin of cellular structure and/having a high compressive strength, a high tensile strength and 'high impact strength, and preferably the shell-section 18 comprises an in situ formed body of foamed poly- Fig. l4 is a further enlarged'fragmentary-lateral se'cy tional view -s'imilarto Fig. 2, of a modified formof the r hatch plug. l. v l 1 l K Referring now -to Figs. l to 3, inclusive, `of thedrawing, a fragmentary portion of a"railway refrigerator car 10 is there illustrated that comprises a steelroof sheet 11 havingra hatch frame 12 formed therein and 'surround'- ing an associated hatch opening 13 formed therethrough, and carrying a hatch plug 14 embodying the features'of the ,k present invention. .More particularly, thel hatchV frame -12 vmay be substantially vrectangulariinplan andis preferably.formed` integrally with `theroofsheetl :andl disposed about the, perimeter `off. ,the .fsubstantially:.rec`
fThe hatch plug 14fcomprisescomplementary'outer and imei-"sections 15 .andlsrsofvvlri'gid molded-structure.
and preferablytformed of synthetic organic resine ,reinurethane resin, such for example, as a polyester group cross-linked with urethane groups. In the arrangement, the core element 17 is entirely embedded in the shell section 18 that is intimately bonded thereto; and also the shell section 18 is intimately bonded to the sections -15 and 16 to retain the elements in assembled relation and.
to provide a unified integral construction. l
The roof'of the car 10 comprises an upstanding lon'- gitudinally extending roof cap 19 formed of steel and joining together the Vabuttingupturned edge anges of the oppositely disposed roof vsheets 11; which roof cap`- 19 carries a pair of longitudinally spaced-apart hinges 2t) Vto which the hatch plug 14 is'secured for pivotal movement into and out of the hatch frame'12 andre'- spectively into closed and open 'positions with ,respect to the hatch lopening 13. In the arrangement, asubstantialf ly rectangular sealing gasket 14a. formed 'of jrnoldefd rubber, or the-like, is Vsuitablyv secured tothe lower sur-ffaceof the ilared boundaryilangej 16C of 'thelOWer see,-k -tion 16 andlpositioned toco'operateA with the associated hatch'lframelZ, so as to seal the 'hatchopening v'Each of the hinges zii comprises a pair of lcomple?- mentary hinge `elements 21 and- 22 secured together'by an` associated pintle 23, the hinge element 21 being' deof rigid molded material, such, *for example, -aslbe'jr glassreinforced polystyrene,;although it is vpreferable .thatthe hinge elements 21-and 22 be formed of-s't'eelThe hinge element 221s vd'etachably securedV to Y. thehatch splug' 11i-when the hatch plug 14 occupies its closed position.-
l14 by a pair of `l-bolts 24 and cooperating nuts 25 and by a bolt 26 and a cooperating nut 27. In the arrangement, the hooks of the J-bolts 24 are disposed between the Asections 15 and 16 and firmly anchored and embedded The stems of the J-bolts 24 further `bolt 26 extends through aligned openings formed in the .marginal ange 16b of the upper section 15 and through lthe hinge section 22 so that the outer end thereof carries the nut 27 for the securing purpose. Accordingly, it will Abe understood that the hatch plug 14 is detachably secured to the hinge sections 22 of the pair of hinges 20, thereby accommodating placement and removal of the hatch plug 14 with respect to the pair of hinges 20, as required.
The hatch plug 14 also carries a pair of longitudinally spaced-apart upstanding stops or bumpers 28 that are suitably detachably secured thereto by cooperating J-bolts 29 carrying nuts 30 on the outer ends thereof; the J-bolts 29 also being embedded in the molded shell 18 in the manner of the J-bolts 24,'as previously described. Further, ,the hatch plug 14 carries a lock 31 and a lifting handle 32; which elements 31 and 32 may be detachably secured to the hatch plug 14 in the general manner of the stops 28 and the hinges 20, as described above. Accordingly, the hatch plug 14 is of sandwich construction that is exceedingly strong `and has an exceedingly low heat transfer factor; and moreover, Athe hatch plug 14 is of very lightweight so that it may be readily moved in a simple manner between its open and closed positions with respect to the hatch opening 13 utilizing the handle 32.
, In manufacturing the hatch plug 14, the upper and lower sections 15 and 16 are separately molded, in the usual manner; and at this time, a number of holes 16d may be formed in the bottom wall 16a of the lower section 16,
as illustrated in Fig. 3. After molding of the upper section 15, the various J-bolts 24 are assembled with respect to the cooperating holes provided in the `top wall 15a thereof and secured in place employing the cooperating nuts 25, as illustrated in Fig. 3. Also the J-bolts 29, etc., are assembled with respect to the upper section 15, in a similar manner. The preformed foamed core 17.is provided that is so constructed that it may be readily enclosed in the cavity dened in the lower section 15 and filling a major portion of the volume thereof. In this connection, it is mentioned that the core 17 may be cut from a commercially produced slab of `teamed polystyrene, as the exact size and the particular shape of the coreY 17 are not critical, since it is employed fundamentally to fill the space that mustotherwise be illed by the ,more expensive polyurethane shell 18. At this time, the
core 17 is arranged in the lower section 16, and the upper section 1S is assembled upon the marginal flange 16C of the lower section 16 and suitably retained in place. For example, the marginal tlangel 16C of the lower section 16 may be suitably cemented to the adjacent undersurface of the `top wall Y15a of the upper section 15 employing an appropriate vphenolic cement. At this time, the core 17 -fills a major por-tion of Vthe void or` cavity disposed between the sections 15 and 16; and preferably Small notches or recesses 17a are formed in the surface of the mentioned, with lthe result that the core 17 and the hooks of the J-bolts 24A and are completely embedded in the molding material that is ultimately productive upon curing of the shell section orlayer 18. Upon curing of the foamed polyurethane rshell section 18, the unitary structure is produced, the shell section 18` being intimately bonded to the core element 17 and to the sections 15 and 16 and to the J-bolts 24 and 29. At this time, the several holes 16d formed in the vbottom wall 16a of the section 16 may be plugged up with a suitable synthetic organic resin, such as a polyester reinforced with glasstibers, as indicated at 16e, in Fig. 2. Then, the nuts 25, 30, etc., carried by the outer ends of the J-bolts 24 and 29 may be removed in order to facilitate securing of thebumpers 28, etc., to the linished hatch plug 14.
Reconsidering the molding of the polyurethane shellr section 18, it is pointed out that a large `variety of molding materials maybe employed, as the system is predicated upon the reaction of polyisocyanate and water to liberate carbon dioxide, while simultaneously the polymerization and cross-linking reactions between the polyisocyanate and the polyester entrap the liberated carbon dioxide; whereby no external blow or vfoaming agent is required. Moreover, the resin is Self-curing, since the reactions are exothermic and take place at room temperature. When Vthe ingredients are mixed employing some water, the reactions are'initiated producing the carbon dioxide gas and the resulting foam; however, suitable catalysts (amines) are ordinarily added to the ingredients to accelerate the reactions and to reduce the ycuring time. -For example, the curing time of a typical molding material can be reduced from about ten hours to about one to two hours by the addition of an appropriate amount of urea. Also the polyesters (alkyd resins) and the polyisocyanates should be selected so as to control the density of the resulting polyurethane resin, as a rigid (or at least a semirigid) foamed structure is desired in the present case. Fortunately, the density of the polyurethane resin may be controlled over a wide range from about 1.5 to about 40 lbs/cu. ft.. by controlling the amount of water employed, the amount of catalyst added, and particularly by selecting the polyisocyanate used for cross-linking; and in general, it is noted that the diisocyanates produce linear polymers of relatively low density and rigidity, while the'triisocyanates and higher polyisocyanates produce more highly cross-linked polymers of relatively high density and rigidity. In the present case, a suitable polyurethane resin (condensation product) may be produced that is formed essentially of copolymers of adipic acid and glycerol cross-linked with naphthyldiisocyanate and some diphenoltriisocyanate.
These polyurethane resins are highly desirable in the present casebecause of the great compressive strength, the high tensile strength, the high impact resistant characteristic, and the exceedingly low heat transfer factor thereof, together with the circumstance that they are Yself-curing at room temperature and may be readily molded in situ, so as substantially completely to fill all of the space into which the foamed molding material isV months. Furthermore, these resins possess the peculiar characteristic of forming tenacious bonds with almost any kind of material in contact therewith during the curing reactions, and including steel, wood, other resins, etc.
Referring now to Fig. 4, a modified form of the hatch plug 114 is illustrated that is fundamentally of the construction and arrangement of the hatch plug 14, previously described, and including the corresponding parts 115, 116, 117 and 118. In this construction, the upwardly and outwardly directed boundary liange 116C of the section 116 is provided with the extension or rim ange 116f that extends outwardly and downwardly therefrom and having a configuration matching that of the rim flange 115b provided on the section 115; whereby the composite flange disposed about the boundary of the hatch plug 114, when the sections 115 and 116 are secured together, is of double-wall construction, as illustrated. This arrangement provides avery strong composite flange about the hatch plug 114, insuring adequate support thereof by the associated hinges, not shown.
Also in construction, a number of the holes for receiving the molding material of which the shell section 118 is produced are formed in the flange 116e of the section 116, instead of in the bottom wall, not shown, thereof; which holes mentioned are subsequently closed with the plugs, indicated at 116e. Because of this relocation of the holes mentioned, the foamed molding material that is productive of the shell section 118 may be injected into the assembly, in the manufacture of the hatch plug 114,
while the assembly is arranged in an upright position. More particularly, the foamed molding material is injected through one or more of the holes mentioned into the space defined between the sections 115 and 116 and surrounding the core sections 117 so as to eifect the produc-l tion of the shell section 118 in the manner previously described.
The remainder of the construction of the hatch plug 114 and the method of making the same are substantially the same as these corresponding items described in conjunction with the hatch plug 14 and are not reiterated in the interest of brevity.
In view of the foregoing, it is apparent that there has been provided a hatch plug for a refrigerator car, or the like, of improved construction and arrangement that is of unitary sandwich construction, exceedingly strong, of light weight and characterized by an exceedingly low heat transfer factor.
While there Ahas been described what is at present considered to be the preferred embodiment of the invention, it will be understood that various modifications may be made therein, and it is intended to cover in the appended claim all such modifications as fall within thev What is vclaimed is:
A hatch plug for a refrigerator car roof, comprising complementary outer and inner sections, said inner section having a substantially pan-like configuration and including a boundary wall carrying an out-turned marginal rim, said outer section having a substantially coverlike configuration and including an out-turned marginal rim, said sections being arranged in assembled facing relation and defining a cavity therebetween and with the rim of said inner section engaging said outer section and with the rim of said outer section embracing the rim of said inner section, the rims of said sections cooperating with each other to provide a composite ange surrounding said hatch plug and adapted to carry a sealing gasket for cooperation with the associated car roof, each of said sections being of rigid molded structure and formed essentially of synthetic organic resin and having a high impact strength, a self-supporting heat-insulating body arranged between said sections and substantially completely filling said cavity and securing said sections together in assembled relation, said body being of composite construction including an inner core element and an outer shell element intimately bonded thereto, said shell element also being intimately bonded to said sections, said inner core element having high tensile strength and being formed essentially of foamed polystyrene and said outer shell element having high tensile strength and being formed essentially of foamed synthetic organic resin including polyurethane, and a pair of spaced-apart securing devices respectively arranged in a pair of spaced-apart holes provided in said outer section, the inner ends of said securing devices projecting inwardly from said outer section into saidv cavity and being so embedded in the outer shell element that the outer shell element bonds said inner ends of the securing devices to the inner core element and the outer section,lthe outer ends of said securing devices projecting outwardly from saidk outer section and being adapted to be respectively secured to a pair of spaced-apart hinges carried by the associated car roof.
References Cited in the ile of this patent UNITED STATES PATENTS 2,552,641 Morrison May 15, 1951 2,565,706 Thompson Aug. 28, 1951 2,607,302 Nystrom Aug. 19, 1952 2,639,252 Simon et al. May 19, 1953 2,660,194 Hoffman Nov. 24, 1953 2,682,111 Kish June 29, 1954 2,753,642 Sullivan July 10, 1956 2,794,756 Leverenz June 4, 1957 2,802,766 Leverenz Aug. 13, 1957 FOREIGN PATENTS 720,956 Great Britain Dec. 29, 1954