US3618429A - Drum cap removing tool - Google Patents

Abstract

A TOOL FOR REMOVING A CAP FROM A DRUM HAS A BASE WITH A CENTRAL APERATURE ALONG THE AXIS OF WHICH A PLUNGER IS MOVED. FROM THE SIDES OF THE PLUNGER A PLURALITY OF JAWS HAVING SHARP ENDS MOVE RADIALLY OUTWARD TO BITE INTO THE ANNULAR WALL OF THE CAP. A SPRING RESISTS THE JAW MOVEMENT. THE PLUNGER END IS A DIE TO ABUT HE CENTRAL PART OF THE CAP AND STRETCH AND DEFORM THE CAP MATERIAL BETWEEN THE JAWS AND THE PLUNGER THUS PULLING THE CAP WALL OUT FROM A RETAINING BEAD ON THE DRUM. THE JAWS CAN TIP SLIGHTLY FOR CAP DISENGAGEMENT.

Description

1971 J. E. FROELIGER 3,618,429

DRUM CAP REMOVING TOOL Filed Sept. 5, 1969 2 Sheets-Shoot 1 AwI/vr'az Jam 4-, FIOIL/Gi! IrraI/VIYI J. E. FROELIGER DRUM CAP REMOVING TQOL Nov. 9, 1971 2 Sheets-Sheet 8 Filed Sept. 3, 1969 mu l/v70! Jam 5 Fun MI? [from 1K! United States Patent ()1 ice 3,618,429 Patented Nov. 9, 1971 3,618,429 DRUM CAP REMOVING TOOL Joseph E. Froeliger, 1967 Gillchrist Ave., i Stockton, Calif. 95205 Filed Sept. 3, 19169, Ser. No. 854,936 v Int. Cl. B67b 7/00 US. Cl. 813.2 Claims ABSTRACT OF THE DISCLOSURE A tool for removing a cap from a drum has a base with a central aperture along the axis of which a plunger is moved. From the sides of the plunger a plurality of jaws having sharp ends move radially outward to bite into the annular wall of thecap. A spring resists the jaw movement. The plunger end is a die to abut the central part of the cap and stretch and deform the capmaterial between the jaws and the plunger thus pulling the cap wall out from a retaining bead on the drum. The jaws can tip slightly for cap disengagement.

' Many commodities are stored or shipped in circular cylindrical drums usually madeof metal and having a capacity of about fifty-five gallons. These drums are filled and emptied through an opening made in the head or in a flattened portion of the otherwise circular cylindrical drum wall. The margins of the opening or apertureare curled or rolled to provide a bead of toroidal configuration. Designed to occupy the opening is a cap, usually of sheet metal, having a central portion, originally approximately planar, surrounded by an upstanding, circular cylindrical wall. Extending from the wall is a flange adapted to overlie or overlap the upper portion of the toroidal bead. The flange is preferably slightly curved and has a gasket or sealing means within the curved portion to engage the toroidal drum flange.

After the drum has been filled, the cap is appropriately positioned and a special forming tool displaces the normally circular cylindrical wall of the cap radially outwardly to underlie the inwardly sloping portion of the toroidal bead. This not only holds the cap in position but also draws down the flange onto the drum' and causes a tight seal. There has been considerable difficulty in removing such caps without mutilating or partially destroying the drum. It is customary to slit or cut into the cap and seal in order to deform the cap and remove it. Sometimes this action also damages the drum, especially the head, so that the drum cannot be reused. Some users actually cut the bead out of the drum thus destroying the 1 from its environment in the drum and to do so in a readily accomplished and satisfactory fashion.

Another object of the invention is to provide a tool for removing a cap from a drum without in any way injuring the drum itself so that the drum can be reused.

A further object of the invention is to provide a tool for removing a cap from a drum which can readily be utilized by even unskilled labor and which can be made readily available at a drum opening site for easy use.

A further object of the invention is to provide a tool for removing a cap from a drum which is unlikely to become deranged and will serve well for a long period.

An additional object of the invention is in general to provide an improved tool for removing a cap from a drum.

Other objects together with the foregoing are attained in the embodiment of the invention described in the accompanying description and illustrated in the accompanying drawings, in which:

FIG. 1 is a cross section on a vertical, axial plane through the cap removing tool, some portions being shown in side elevation;

FIG. 2 is a cross section the plane of which is represented by the line 2-2 of FIG. 1;

FIG. 3 is a framentary cross section, like FIG. 1 and showing the tool in initial position on a drum;

FIG. 4 is a fragmentary cross section like FIG. 3 and showing the tool in a final position on a drum; and

FIG. 5 is a framentary cross section like FIG. 3,and showing the tool in a removed position with respect to the drum.

While the tool for removing a cap pursuant to the invention can be embodied in a number of different ways and is also susceptible to variations to adapt it to particular drum caps, it has with considerable success been utilized in the form shown herein. This environment the tool is utilized in connection with a circular cylindrical drum wall or head 6 which has a flattened portion in which the margin 7 of a central opening 8 in the drum is curled back upon itself to provide an annular rim 9 or bead, the opening and rim being generally symmetrical about an axis 10. The material of the drum and particularly of the rolled or annular rim 9 or bead is usually steel of substantial stiffness.

To cooperate with and seal the drum there is customarily provided a cap 11 likewise of relatively stifi steel. Initially the cap is a generally circular body symmetrical about the same axis 10 and having a generally planar central portion 12 which merges through an easy curve into a curved flange 13. The interior or underside of the arcuate flange 13 is provided with a gasket 14 or sealing material.

In the usual installation the cap is readily inserted into position blocking the aperture 8 because initially the side wall 15 of the cap is circular cylindrical and slightly lesser in outside diameter than the inside diameter of the opening 8. After the cap has been positioned and rests with the gasket 14 on the upper portion of the bead 9, a special tool deforms the cap, usually by partially deflecting the central portion 11 and particularly enlarging the diameter of the side wall 15 so that a portion of the wall bulges outwardly and underlies the bead on the drum. This engagement isforceably made and the deformation of the cap is accompanied by a drawing'down of the flange 13 so that a very tight seal is made.

In order to remove a cap so installed, the tool of the invention is employed. This tool includes a base'21 of metal which is generally circular cylindrical and is hollow defining a central cavity 22, all being symmetrical about the axis 10. 1

Mounted on the base 21 is a body 23 secured to the base by a plurality of fastenings 24. The body is extended to end in a threaded connection 26 into which a hydraulic jack cylinder 27 can be screwed. A screw or cam jack or air operation are also suitable. The cylinder 27 is preferably a standard part of a commercial hydraulic jack and has a connection 28 for the attachment of a hydraulic supply and return line (not shown) by which the interior of the jack cylinder 27 can be pressurized when desired. Reciprocable within the cylinder 27 is a jack piston 29 resting upon an enlarged flange 31 near the upper end of a plunger 32 movable through a central opening 33 in the body 23. A relatively heavy coil spring 34 is interposed between the body 23 and the flange 31 and tends to urge the plunger 32 upwardly and the piston 29 in a direction into 3 the jack cylinder 27, the force being sufficient to empty the jack cylinder 27, when desired.

Included in the plunger is a threaded interconnection 35 between a reduced stem 36 of the plunger and an enlarged head 37 thereof. The enlarged head is particularly configured to afford a generally circular cylindrical side wall 38 freely reciprocable within the chamber 22. The side wall of the head in turn merges with a rounded end die 39, all symmerical about the axis 10. In the uppermost position of the plunger, the die 39 is retracted into the chamber 22.

The body 21 at appropriate intervals around its periphery is provided with a number, usually six, of radial slots 41 each having substantially parallel side walls 42 and 43 and an upper wall 44 inclined upwardly and inwardly.

Designed to slide freely within each of the slots 41 is one of a number of jaws 46 each of which is primarily a generally rectangular block having arcuate ends. At the inner end the arcuate portion of the block is contoured to provide a large diameter cylinder surface 47 and a small diameter cylinder surface 48 with an intervening, conical cam surface 49. The outer configuration of each of the jaws includes a toroidal groove 51 in which is lodged a circumferential, garter spring 52 urging the jaws radially inwardly. Below the garter spring groove 51 each jaw is particularly undercut to define a recess 53 neXt to an enlarged sharp ledge 54 preferably interrupted at intervals to afford a series of teeth 56. Disposed beneath the jaws and fastened to the body 21 is a removable securing ring 57 helping to confine the jaws.

In use, this tool is positioned over the cap to be removed with the axis substantially perpendicular to the subjacent portions of the drum and with the spring 34 fully extended and the plunger 32 in its upper most position. Having been appropriately so positioned, the tool is then activated by introducing fluid under pressure to the jack cylinder 27. This moves the piston 29 and the plunger 32 axially downwardly, incidentally compressing the spring 33, and driving the plunger curved tip 39 or die against the cam surface 49 of the various jaws.

As the die descends the jaws are moved simultaneously in a radially outward direction, also tensioning the garter spring 52 and as the jaws move outwardly, their flanges and teeth 56 engage with the bead 13 of the cap. Preferably, there is a substantial deformation of the wall of the cap material. Although the teeth preferably do not pierce the wall material, they do dig into it to a substantial extent so that the tool is given a firm anchorage in that part of the cap.

Continued plunger movement downwardly along the axis 10 causes no more outward camming of the jaws but does bring the rounded die 39 downwardly into abutment with the central portion 11 of the cap. Further downward movement of the plunger die deforms and draws down the cap material and tensions that material between the anchor points at the teeth 56 and the die portion of the plunger. The material is stretched and moved generally inwardly and downwardly so that the previously existing indentation of the cap under the head is removed. The deformed cap turns out to be approximately spherical in an inward and downward direction and is so deformed that its inner portions are all of lesser diameter than the opening within the drum head. The tool and the cap can be withdrawn together, leaving the drum aperture unobstructed.

Following this the pressure within the hydraulic cylinder 27 is relieved and the plunger 32 is driven axially in a generally outward or upward direction by the spring 33.

As the plunger returns to its initial position, the garter spring 52 likewise drives in the various jaws. This movement normally is sufficient to disengage the projecting teeth 56 from the substantial indentations they have made in the cap material. Occasionally there is some tendency for the jaws and the deformed cap not to disengage readily. For this reason the inclined surface 44 affords appropriate clearance in an axial direction for each of the jaws so that as the plunger is retracted inwardly the friction against the inward end of the jaws tends to tip or incline them slightly approximately about the garter spring 52 as a fulcrum and aids in withdrawing the teeth from interengagement with the cap. The jaws are thus freed from the cap.

The cap having been removed, the tool is then again in its original position ready for a subsequent operation.

Extensive practical use has demonstrated that the tool can be operated by almost anyone without substantial instruction and is effective to engage securely and to deform and withdraw the cap from a drum of the sort mentioned without any damage whatsoever to the material of the drum or to the configuration of the aperture.

I claim: I

1. A drum cap removing tool comprising a base having a central opening symmetrical about an axis, means on said base adapted to move thereon radially of said axis, circumferential teeth on said means disposed substantially in a plane normal to said axis and movable with said means into and out of holding engagement with the wall of a drum cap, a plunger axially movable on said base through said central opening and in camming engagement with said wall engagement means, means on said plunger adapted to abut the central portion of said drum cap, and means for moving said abutting means axially away from said teeth and thereby tension said drum cap between sadi abutting means and said teeth.

2. A drum cap removing tool as in claim 1 in which said radially moving means is a jaw having an arcuate periphery with a sharp cap-engaging portion extending circumferentially along said periphery.

3. A drum cap removing tool as in claim 1 in which said Wall engagement means is a plurality of jaws arranged radially about said central opening with said teeth arranged circumferentially thereof.

47 A drum cap removing tool as in claim 1 in which said base has radial channels each defined by an upper wall and side walls and in which said wall engagement means are jaws slidably disposed in said channels and having top walls normal to said axis, said upper wall being inclined in an upward and inward direction.

5. A drum cap removing tool as in claim 3 including a circumferential spring arranged around the periphery of said jaws to urge said plurality of jaws toward said central opening.

References Cited UNITED STATES PATENTS 233,050 10/1880 Tully 72393 302,884 8/1884 Brady 8l72 X 869,861 l0/1907 Alspaugh 8l72 UX 1,390,371 9/1921 Meyer 8l72 2,811,067 10/1957 Greer 8l72 3,473,499 10/1969 Bishop 8l3.2

ROBERT C. RIORDON, Primary Examiner R. V. PARKER, JR., Assistant Examiner US. Cl. X.R. 29427; l13l

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