US 2538693 A
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Jan. 16, 1951 MAlSCH 2,538,693
SHELL LIFTING AND SEALING PLUG Filed Feb. 1, 1949 Patented Jan. 16, 1951 amino STATES PATENT oFFicE 2,538,693 SHELL LIFTING AND SEALING PLUG Oliver Maisch, Chicago, Ill.
Application February 1, 1949, Serial No. 74,035
1 Great quantities of ammunition in the form of loaded shells are kept in underground storage where the surface finish gradually deteriorates. After being so stored for a considerable length of time, the shells must be refinished before they can be used. These shells commonly have in one end a screw threaded opening into which are screwed lifting devices, by meansof which shells may be suspended from carriers for transportation and manipulation. After a shell has been refinished, the lifting device must again be unscrewed. The screwing in and unscrewing of a lifting device takes considerable time and therefore adds very substantially to the labor'cost of handling and refinishing the shells.
The primary object of the present invention is to produce a simple and novel lifting device that can be applied to and removed from a shell quickly and easily, thereby substantially decreasing the amount of labor required to perform these operations and making them less expensive.
In carrying out my invention I employ an expansible plug that can be slipped into the screwthreaded opening of a shell and then be expanded quickly into interlocking relation with the" surrounding screw threads; the parts that engage with the metal of the shell being of flexible rubber or rubber-like material, which not only creates the desired interlock without marring the screw threads, but also sealsthe opening. into which the device, is inserted.
Therefore, viewed in one of its aspects, the present invention may besaid to have for an object to produce a simple and novel, threadless, and quickly attachable and detachable plug for sealing a screwthreaded opening in a shell or any other article without marring the screw threads and without requiring that the thread be'of some particular type, pitch, or size; the plug being provided with means, if desired, for suspending and carrying the article in which the opening exists.
The simplest way of expanding the plug is to provide it with a camming handle which, after e ch ing the position necessary for'proper exp ns'ion'of the plug, will remain in'tliatposition whilebeing employed to suspend the shell or other article from a hook or other support; thus locking the handle. inthe position to hold the plug in place until the handle is relieved of the weight of the article.
'Con'sequent1y, one of the objects of the present invention may be said to be toprovide a quickly attachable and detachable expansible' sealingof a shell into the screwthreaded opening of" which a device embodying the present invention has been inserted, preparatory to being interlocked therewith; Fig. 2 is a section on line 2-2 of Fig. 1, showing the device locked in place; and Fig. 3 is a section on line 3-3 of Fig. 1. 1
In the drawing I have illustrated my invention as adapted for lifting and sealing an artillery shell and, for the sake of brevity, shall confine the detailed description to this particular use; it
being understood that the device is not limited to'use only in this particular field, but may be used wherever there may be an advantage in so doing.
' In the drawing, A is a fragment of a conventional artillery shell having in one end a large opening provided with internal screw threads B. In the inner end of the opening is fitted a conventional fuse well cup C that seals the opening at all times. The specific plug device illustrated comprises a body member l of soft rubber having a main cylindrical section 2 provided at one end, the upper or outer end, with a part 3 of greater diameter that constitutes a head. The cylindrical portion is hollow, so that the body member has the shape of an inverted cup, the cylindrical part of which is small enough in diameter freely to enter the opening in the shell,
while the laterally protruding part of the head rests onthe portion of the shell around andim-I mediately adjacent to the opening; the flange may have an edge portion that is frusto-conical as shown at 4; so that this portion of the body member may be wedged into the opening in-the shell if pressed down. Within the part [is a stiff metal sleeve 5 somewhat shorter alanine depth of the cup, to prevent the cylindrical wall of the cup from being pushed inwardly toward the axis. i
Underlying the rubber body member is a thick, rigid metal disc 6 ofthe same diameter as part- 2 of the body member. On top of the body mem;
her is a se'cond' rigid of the same diameter as the head section 3. An axial stem 8 extends loosel through disc '5 and head 3 of the body member and through and in screwthreaded relation to disc 6; Q being the screw threads on the lower end of the stem. A lock nut I9 is screwed on the lower end of the stem below and in engagement with the lower disc. The stem terminates in an eye a little above the upper disc. Embracing this eye is a fork l2 on one end of a short handle it. A pin' l5, extending through the two prongs of the fork and the interposed eye, effects a hinge joint between the handle and the stem. The end edges 16 at the free ends of the prongs of the fork are cams which have flattened portions ll intersected by a plane containing the axes of the handle and hinge pin. The-free end of the handle is in the shape of a large eye E3, the plane of which is parallel to the plane just mentioned.
The parts are so proportioned that when the handle is swung down to lie parallel with the topor": the upper disc, there is a clearance between the fork portion of the handle and the upper: disc, so that there is no pressure on. the rubber member. When the handle is swung up, however; the cam sections of the fork approach and finally engage and force down the upper disc; By the time that the handle has swung. through. an angle of ninety degrees and is thus aligned with the stem, the flat edge portions ll of the cams rest for their whole lengths onthe disc. and thusqserve to hold the handle so'aligned withithe stem. During such swinging movement of thehandle, the discs are drawn toward each other, compressing the rubber body member; and,
since sleeve 5: prevents movement of the rubber toward the center, the cylindrical part increases in external diameter.
In using the device, the handle is set in its idle or" release position and the plug is slipped into the? opening; inthe shell, coming to rest when the rubber flange engages the shell. The situation is now that illustrated in Fig. 1-. It will be noted'thatthe lower disc i: is an aid when enter ing the plug in the opening, because it is not only smooth but is rigid and does not become distorted if it touches the threads in the shell opening. After the plug has been set into the open ing, the handle is swung up, as in Fig. 2, therubber being expanded into the valleys of the:
threads. B and forming an eifective interlock. The: eye it on'the handle presents a large: area: against which the palm of a hand may press; forcibly to. swing the handle into its upright po--- sition. It should also be noted that lower disc 6. serves not only as a guide in' entering the plug inthe opening and as an anvil on which therub ber body member-rests, but keeps the body member centered: in the opening and insures; even. expansion thereof: in all radial directions.
The grip of the plug'is so great that shells each. weighing several hundreds of pounds may be; lifted and carried from place to place by supporting this entire weight from the plug.
TheeX-pan-ded plug efiectively seals the open-- ing in the shell so that no foreign matter can. enter such. opening while the plug is.interlocked. with the shell. If a shell be repainted, for exe ample, nopaint can enterv the opening'withthe plug in place. The flange on thebody member provides the first sealing line, as it is compressed more or. less and forced tightly against the metal edge surrounding the opening in the shelland to. some: extent against the: marginalportior of the surface; of. the: shell around thezopening,
shown in Fig. 2. Also, when expanding pressure is applied to the rubber body, the rubber in the head section thereof is pressed tightly against that portion of the stem surrounded thereby, so that an efiective seal against outward leakage of fluids along the stem is created.
After the work to be done on the shell is completed, the plug may be removed by simply swinging the handle down and lifting the plug out; the elasticity of the rubberv being such that the body m mber resumes itsoriginal shape'upon release or" the pressure.
It should be noted that although I have shown my device only'as applied to a screw threaded opening, it may be used in threadless openings, as well; particularly where the main purpose is to seal an. opening. In theconstruction illustrated, the threads B in efiect constitute annular shoulders underneath which the rubber ridges lie when the plug has been expanded into the opening in the shell; Therefore it may be said. that: the. lowermost thread engaged" by the rubber seals the inner or lower end of the opening. Thus the'prin-- eiple is the same; in" this; respect, as when the" plug is inserted in an opening or bore of' less axial length than the bore, so that the rubber extends down below the lower end of" the bore; so that, in expanding; therubber bulges laterally underneath an annular shoulder'that surrounds the lower'end'of the bore-and creates a seal.
While" I have illustrated and described with particularity only a singl'epreferredform of my" invention, I do not'desire to be limited to the" exact details thus illustrated and described, but-' position. transverse-to the stem,. means at the. other endofthe handleto-attachit to -a suspends ing device, an eX-pansiblemeans including a:--cy lindriealbodymember of sofitrubber. surround? ing' and in spaced relation to'the stemand rig-id. platesoverlying and underlying. the body'mem-- ber, and'a'nut on the lower end of the'stem, and a camon. the hinged end of the handleengaging; said plate to force: the"- expanding means; down. against the lower of said plates and: cause: the body niember'to expand laterally whenithe handle: is swung into alignment'with the stem. and. to: allow the body member to resume its norma'h diameter when the handle is swung intoits' sec end position.
2'.' A combined sealing and lifting plug coma prising a stem having-a nut on one end; a handle hinged at one end to the other end of the stem: so as to be movable from a position in alignment" with the stem to a second position transverseto the stern, an expansible means including a cylindrical body member ofsoft rubber in the form of an. inverted cup. and underlying and overlying rigid discs surrounding the stem and' resting onsaid nut, a rigidsl'eeve, shorter than thedepth of the cup, filling within the cup, a.nd'. a cam on the hingedLend of the handle engaging the nearer disc to force the. expanding means down against saidnut andcause the body member. to .expandlaterally. when =the.handl'e is into. allgmnentwith. thel stem; and; to allow the:
5 body member to resume its normal diameter when the handle is swunginto its second position.
3. A plug device comprising a rubber body member in the form of an inverted cup, rigid clamping plates arranged one above and the other below said body member, a stem extending loosely through the upper plate and the cup bottom of the body member and extending also through and in screwthreaded relation to the lower plate, a nut on the lower end of the stem engaged with the lower plate to lock it against downward movement on the stem, a cam device on and hinged to the upper end of the stem to force the upper plate down to compress the rubher and cause it to expand laterally, and a part on said cam device that serves as a handle.
4. A plug device comprising a thick body member of flexible rubber in the form of an inverted cup, a sleeve somewhat shorter than the depth of cup fitted in the cup to prevent the wall of the latter from being deflected inwardly, rigid clamping discs, one above and the other below said ody member, a stem extending loosely through the upper disc and the body member and also through and in screwthreaded relation to the lower disc, a nut on the stem below and in engagement with the lower disc, a cam device hinged to the upper end of the stem in position to engage the upper disc and force it down so as to compress the rubber member and cause it to expand laterally, a handle fixed to the cam device in position to be aligned with the stem when the said cam device is in clamping position, and said handle containing an opening to receive an element adapted to suspend the plug device and an object to which the latter is attached.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number 7 Name Date 1,212,871 Abbott Jan. 16, 1917 FOREIGN PATENTS Number Country Date 1,788 Great Britain of 1879