US2560793A

US2560793A - Tamperproof closure for receptacles

Info

Publication number: US2560793A
Application number: US132044A
Authority: US
Inventors: Greene Edgeworth
Original assignee: INTER SEAL CORP
Current assignee: INTER SEAL CORP; INTER-SEAL Corp
Priority date: 1949-12-09
Filing date: 1949-12-09
Publication date: 1951-07-17
Anticipated expiration: 1968-07-17

Description

July 17, 1951 E. GREENE TAMPER-PROOF CLOSURE FOR RECEPTACLES Filed Dec. 9. 1949 f i" .1417 y la 23 Z5 J5 :Nvx-:NroR fafwomw GREENE mm5 ATTORNEYS` Patented July 17, 1951 UFFICI?.`

TAMPERPROOF CLOSURE FOR RECEPTACLES Edgeworth Greene, Great Notch, N. J., assignor to Inter-Seal Corporation, Spring Lake, N. J., a corporation of Delaware Application December 9, 1949, Serial No. 132,044

This invention V relates to closures vfor sealing containers, such as bottles, andV is concerned more particularly with a novel closure, which cannot be removed from the container without the breakage of parts of the closure. The closure of the invention is similar to that shown in my Patent 2,409,846, issued October 22, 1946, but differs from the patented closure in that it is provided `with an improved inner or locking member.

cooperating parts, which cause the cap and member to move in unison, when the cap is threaded on the neck to seal the latter. When an attempt is made to unscrew the cap, the cooperating parts mentioned act to wedge the member and cap apart and force is thereby applied to an area of the cap which is bounded by a circular weakened area. The locking member is of novel construction and so made that it is somewhat distorted by the strain referred to. When the strainson the cap and member have built up suiciently, the weakened area of the cap is suddenly ruptured and the portion of the cap bounded thereby is thrown free of the closure by the spring back of the inner member to its normal condition. The use of the new inner member thus insures a clean break of the cap throughout its weakened area and a complete ejection from the closure of a part of the cap.

For a better understanding of the invention, reference may be had to the accompanying drawing, in which Fig. 1 is a central vertical sectional view, partly in elevation, of a bottle closure embodying the invention;

Fig. 2 is a View similar to Fig. 1 but showing how the crown of the cap of the closure is thrown free when an attempt is made to unscrew the closure from the bottle;

Fig. 3 is a central vertical sectional View, upon an enlarged scale, of the locking member of the closure; v

Fig. fi` is a top plan View of the locking member; and

Fig. 5 is a fragmentary bottom plan view of thev locking member.

1o claims. (01."215-42) In the drawing, there is illustrated one form of closure embodying the invention, which is adapted to be mounted upon the neck I 0 of a bottle, the neck being provided with a conventional external thread II. The closure includes a cap I2, which may be conveniently molded of a plastic material and has a skirt I3 with an internal thread I4 engageable with the thread II, and a crown I5, the under surface of which is concave. The crown is connected tothe outer. part of the cap by a narrow annular weakened area I6. The cap is provided on the inner face of its crown with at least one projection I1, and preferably with a plurality of like projections arranged in a circular series. Each projection has a front vertical wall E8, which leads, when the cap isrotated to screw it upon the bottle neck, and a surface I9, which extends upwardly and rearwardly from the free end of the projection. In the closure illustrated, the cap has four projections I1 and the cap is rotated clockwise to thread it upon the bottle neck.

The top of the bottle neck is sealed by a gasket 20 of suitable compressible material, such as composition cork, the gasket preferably being provided with facings 2 I, 22 of sheet material on its upper and lower faces. The lower facingy is preferably made of or coated with a material, which resists slippage when the gasket is compressed against the end of the bottle neck.

An inner or locking member 23 is disposed between the cap and the gasket. The locking member is of circular form and it is provided with a flat circumferential flange 24, which rests upon the top of the gasket in alignment with the wall of the bottle neck. The under surface of the ange is preferably roughened, as, for example, by forming it with a series of radial ratchet teeth 25, the sloping surfaces 26 of which extend upwardly and forwardly in the direction of rotary application of the cap. Outwardly fromv flange 24, the member may advantageously be formed with a concave stiffening bead 21, which is engageable by the under surface of the cap outwardly from the weakened area I6.

The locking` member is provided with at least one vertical wall 29 engageable with the front wall I8 of a projection Il on the cap and preferably also has a surface 3U, which slopes upwardly and rearwardly to the top of the ver'- tical wall, so as to be engageable with the sloping surface I9 on a projection Il. The vertical and sloping walls are formed on a part of the locking -member which is distortable and resilient and, for this purpose, the walls are formed in the central part of the member bounded by flange 24 and lying above the open end of the neck of the bottle when the closure is applied thereto. Preferably, there are a plurality of pairs of vertical and slop-ing walls on the locking member, so that even though the member is inserted into the capwithout careful orientation, the front verticalwall of each projection on the cap will lie opposed" and close to a vertical wall on the member and the sloping wall of the projection will lie above a sloping wall in the member.

The central portion of the locking vmember may be nat with the vertical and sloping walls e formed on projections rising from theplane of the member or the central portion may bedepressed and provided with projections having the vertical and sloping walls. In the preferred form of the member, its central area is raised or up' wardly domed and formed with a series of depressions 28, each of which has a vertical wall v2&3

lwhich leads in the direction of rotation of the cap. Each depression also has a wall 30 slop- 'ingupwardly and rearwardly from the bottom of the depression to the top of the vertical wall of the following depression. The depressions 28 are .of a shape and size to receive the projections on thel'lcap, so that, when the locking member is inserted into the cap, the projections on the cap enter the depressions and the vertical and sloplilng surfaces I8, I9 on each projection lie in opposition, respectively, to the

walls

29 and 30 of a depression.

When the parts are assembled in the manner described and the closure is placed upon the end of the bottle neck with the end of the neck entering theskirt of the cap, the rotation of the cap causes its thread I4 to engage beneath the external thread I I on the bottle neck and, as the rotation of the cap continues, the cap is moved vinwardly along the neck. During the rotation of the cap, the engagement of the vertical wall I8 of each projection with the vertical wall 29 of a depression in the locking member causes the member to rotate with the cap. As the rotation proceeds, the cap forces the locking member against the gasket, so that the latter is compressed against the end of the bottle and neck. During the rotation of the locking member with 'the cap, the sloping surfaces 26 of the ratchet teeth on the locking member are in leading position and the teeth slide along the top surface of the gasket and nally become embedded therein as the latter is compressed. When the cap has been thoroughly tightened in place, the gasket is compressed against the end of the bottle neck by the ange 24 on the locking member and the member is held in place against the gasket by engagement of the inner surface of the cap outside the annular weakened area I6 with the top of the bead 21 on the member.

If an attempt is now made to counter-rotate rthe cap, so as to unscrew it from the bottle neck,

the sloping surfaces I9 on projection ITon the cap begin to slide up the sloping surfaces 30 of the depressions 28 formed in the upper surface of the inner member. During such movement of the cap relative to the inner member, the latter is held against rotation by the vertical faces on its ratchet teeth 26, which have been embedded in the top surface of the gasket. As a result of the counter-rotational movement of the cap relative to the locking member, the pressure on the bead 21 is relieved and force is applied to the domed central section of the inner member tending to force it inwardly and slightly distorting it. An equal and opposite force is applied to the sure can then be unscrewed from the bottle neck in the usual way, and the absence of the crown vfrom the cap shows that the bottle has been opened. When the bottle is again to be closed, the cap is threaded on the bottle neck and, when the cap is tight, the bottle is sealed by pressure applied by the cap through the locking member to the gasket.

' `The new locking member is made of sheet material and preferably of sheet metal. It can be formed by stamping at little expense and, when made with the raised central portion, it forms `a rigid structure, even though made of light gauge stock having a thickness as little as .010" or' '.015. The depressions formed in the central portion stiffen the metal and, when the member is domed, the annular section of arcuate shape, which extends between the outer edges of the depressions and the vinner edge of the circumferential flange 24, resists inward distortion of the domed part of themember, when pressure is applied thereto during counter-rotation of the cap. The form of the member is such that it provides the desired resistance during counter-rotation of the cap and stores sufcient energy so that the cap is rupturedfcleanly along its annular weakened area. When the rupture has occurred, the member snaps back to its initial shape and the crown of the cap is vigorously ejected. The formation of the inner member with the central domed portion offers the further advantage that, when the crown of the cap has been ejected, the top of the inner member occupies a position close to the top level of the cap giving the closure a morepleasing appearance than would otherwise be the case. At the same time, the rigidity of the inner member prevents it being accidentally deformed in an inward direction, when the closure is used to reseal a bottle that has once been opened.

In constructing the new closure, it is important that inner znember of the cap have such resilience and the weakened area of the cap have so limited a strength, that the amount of torque required to remove the cap be not substantially greater than that required to unscrew an ordinary screw bottle cap. The weakened area must be weak enough to break readily upon the vapplication of a relatively limited force applied by the cap under torque and yet sufficiently strong, when it is reinforced by the contacting surfaces ofthe inner member beneath it and the corresponding surfaces of the crown of the cap, to resist exterior shocks ordinarily encountered. The inner element must be sufliciently resilient to respond effectively to forces at least no greater than are required to break the weakenedarea of the cap. The inner element must thus be of suitable material and construction, so that it is capable of building up tension progressive in intensity, until such time as the breaking point'of the weakened area of the cap is reached. Experience has shown that the weakened area of the cap of the present closure may be from .010" to .020" thick, since a cap with a weakened area. of such thickness meets the requirements mentioned above and is practical to manufacture. When the cap is made of the material known commercially as Bakelitef a. weakened areal yof .010 to.020"' thick will withstand a static force of approximately 50 lbs. before rupturing and it is not necessary to apply excessive torque to the cap to effect the rupture. Thetension necessary to rupture such a cap may readily be built up progressively in an inner member, which is of the domed construction shown in Fig. 3 and is made of tinplate about .012" thick.

It has also been found desirable to construct the cap and inner element, so that, as the cap is tightened upon. the bottleneck, the opposed surfaces i9 on the cap and 39 on the inner element will engage one another at the same time as, or slightly in advance of, contact between the top surface of bead 2ll and the under surface of the cap directly above it. Whenl this construction is employed, undesirable rotary play between the cap and inner member, after the cap has been tightly applied, is avoided. Also, when the sur- :faces IS and Sil engage slightly in advance of` any thrust being taken by bead 2l', preliminary tension is built up in the domed central section of the inner element, as it is deliected during the application of the cap, and, although this initial tension in the inner member is, of course,.in'1 suflicient to cause rupture of the cap, it necessitates less rotary movement of the cap to effect such rupture. With the construction described, the cap has a more positive feel and, when it is unscrewed, rupture of the cap occurs more promptly.

The use of a flexible inner member affords a further advantage, in that, as the central domed area of the member is depressed, the annular bead 21 on the member tends to rise. lTlhe bead thus quickly meets the cap and takes the major thrust thereof.

In the construction formed with a plurality of projections l', each having a vertical face I8 and a surface I9 sloping upwardly and rearwardly from the end of the projection, and the locking member is formed with an equal number of depressions, each having a vertical wall 29 and a wall 3D sloping upwardly and rearwardly from the lower end of the depression. It will be apparent that various alternative constructions may be used, as, for eX- ample, the cap may have a single projection,

which includes as an essential a vertical face like face I8 and is otherwise shaped as desired, while the locking member is formed with a vertical and a sloping wall like

walls

29 and 30, respectively. Instead, the projection Vand depression described may be formed on the locking member and cap, respectively. The necessity of orienting thev member and cap in assembling them may be avoided by providing a lug on one of these parts and a plurality of depressions on the other.

In the appended claims, the term rotation is intended to refer to rotary movement of the closure by which it is applied to the container and counter-rotation refers to rotary movement of the closure by which it is released from the` container.

I claim:

l. A closure for sealing the opening through the end of a container, which comprises an outer cap adapted for rotary -application to the end of the container, a metallic locking member within the cap, the member having an annular portion adapted to overlie the end of` the container and a resilient central portion adapted to overlie the opening and raised above the level of the annular portion, and gasket means adapted to rest ontheendof the container to close theopeningthe illustrated, the `Cap `isr that, upon rotation of the cap, they engage positively andi-cause the locking member to rotate with theicap to force the lockingmember against the gasket-means and apply pressure thereto, said cooperating parts also having other opposed surfaces, 'at least lone of said other opposed surfaces being inclined in such direction and at such an anglethat, upon counter-rotation of the cap, said other opposed surfaces engage and slide relative to one another to urge the cap away from the locking member and rupture the weakened, area, said cooperating parts being carried, re` spectively, by the portion of the crown of the cap within thew'eakened area and by the resilient central portion'of the locking member.

2. A closure for sealing the opening through the end .ofa container having an annular sealing surfacearound said opening, which comprises an outer cap adapted to t over the container end and having means engageable beneath external means on the container end, upon rotation of the cap, to move the cap inwardly along the end and to hold it in place thereon, the cap having a central portion of its top surrounded by a weakened area and at least one projection from its inner face, theprojection having a vertical face, which leads during rotary application of the cap to the container, and a face sloping upwardly and rearwardly from the free end of the projection, gasket means within the cap and adapted to rest upon the annular sealing surface of the container and close the container opening, and a locking member of sheet metal Ibetween the crown of the cap and the gasket means, the locking member having a circumferential flange contacting the gasket `means in alignment with the annular sealing surface of the container end, and a central resilient portion adapted to overlie the opening and raised above the level of the iiange, the edge portion of the flocking member outwardly from. the flange being raised above the flange and contacting the crown of the cap outwardly from said weakened area, the locking member being formed with at least one vertical wall and a wall sloping upwardly and rearwardly to the top of said vertical wall, the vertical and sloping faces on the pron jection lying opposed, respectively, to the vertical and sloping walls on the locking member, thev projection being carried by the central portion of the cap within the weakened area and the vertical and sloping walls being formed in the resilient kcentral portion of the locking member overlying the open end of the container.

3, A- closure for sealing the opening through theend of a' container, which comprises an outer cap member adapted to be applied to the end of the container by rotation, an inner locking inem-V ber, the cap member having a central area surrounded byan annular weakened area and the metallic locking' member having a circumferential flange adapte'd to overlie the end of the container around its opening and surrounding a re1- silient' central area overlying the open end of the container and raised above the level of the flange, one of the members having a projection from its central area formed with a vertical surface and a surface sloping upwardly and rearwardly from the free end of the projection and the'other member having a vertical wall rising from itsic'entral area and a wall sloping' upwardly and rearwardlyxto the topof the vertical wall,-

amazes 7 the vertical and sloping surfaces onthe projecf tion lying opposed, respectively, to vertical and sloping walls, and gasket means Within the cap outside the inner member and adapted to close the container opening, the .verticalsurface on one member engaging the vertical wall =of the other to cause the members to move in unison during rotation of the cap member and the sloping surface and sloping wall sliding upon one another during counter-rotation of the cap member4 to wedge the central areas of the members apart with coincident deformation of the resilient central area until the cap member is ruptured through its weakened area and its kcentral portion is thrown free by return of the resilient central area to normal position.

4. An inner locking member for use in a closure for sealing the opening through the end of a container, which comprises a disc having a peripheral ange and a resilient central part lying` offset above the plane of the flange, the central part of the member being formed. with at least one pair of walls consistingof a vertical radial wall and a wall sloping downwardly clocks wise from the top of the vertical wall. L t

5. A closure for sealing the opening through the neck of a container, which comprises an outer cap adapted to t over the end ofthe neck and having means engageable beneath external means on the neck, upon rotation of the cap, to move the cap inwardly along the neck and to hold it in place on the neck, the cap having a substantially continuous annular weakened area and at least one projection from its inner face'and lying, inwardly from said area, the projection having a'vertical face, which leads during rotation of the cap, and a face sloping upwardly and rearwardly from the free end of the projection, gasket means within the cap and engageable'withthe end of the neck, the gasket means adapted to close the neck opening and being capable of re sisting slippage relative to the neck when under pressure, and an inner member of sheet metal between the cap and the gasket means, the inner member having a circumferential ange resting upon the gasket means in alignment with the wall f the neck, the central part of the inner member overlying the opening being outwardly domed and formed with at least one depression for receiving the projection on the cap, the depression being defined in part by a vertical face and a face sloping upwardly from the bottom of the depression, the vertical face and the sloping face of the depression lying opposed, respectively, to the vertical face and the sloping face on the projection.

6. A closure for sealing an opening through the end of a container, which comprises an outer cap adapted to t over the end of the container and having means engageable beneath the external means on the container, upon rotation of the cap, to move the cap inwardly along the container and to hold it in place thereon, the cap having a substantially continuous annular weak-- ened area, gasket means within the cap adapted to close the opening and engageable with the end of the container, the gasket means being capable of resisting slippage relative to the end of the container when under pressure, and a locking member within the cap and having a circumferential flange resting upon the gasket means in alignment with the end wall of the container, the central part of the locking member within the ange being resilient and offset upwardlyfrom the plane of the flange, the cap and locking member having cooperating parts providedxwith op.-

gio

posed surfaces, which engage positively, upon rotation of the cap, and cause the lockingmember to rotate with the cap and to be forced against the gasket means and apply pressure thereto, said cooperating parts also having other opposed surfaces at least one of which isin-V clined upwardly and rearwardly so that, upon counter-rotation of the cap, said other opposed surfaces engage and slide relatively to one another to urge the cap away from the locking member and rupture the weakened area of the cap, said cooperating parts being carried, re-f spectively, by the portion of the cap within the weakened area and by the resilient central part of the locking member.

7. An inner locking member for use in a closure for sealing an opening through the end of a con-A tainer, which comprises a disc of sheet metal having a substantially flat circumferential ange and a raised central part, said part having a se.-4 ries of depressions leading inwardly from its raised surface, each depression having a vertical wall, which leads when the member is rotated clockwise, and a wall sloping upwardly and rearwardly from the bottom of the depression.

8. A closure for sealing the opening through the neck of a container, which comprises an outer cap adapted to t over the end of the neck and having means engageable beneath external means on the neck, upon rotation of the cap, to move the cap inwardly along the neck and hold it in place thereon, the cap having the central portion of its top surrounded by a weakened areaand at least one projection from the inner face of said central portion, the projection having a vertical face, which leads during rotary application of the cap to the container, and a face sloping upwardly and rearwardly from the free end of the projection, gasket means within the cap engageable with the end of the neck to close the opening, and a locking member of sheet metal between the crown of the cap and the gasket means, the locking member having a circumfer` ential iiange contacting with the gasket means in alignment with the end of the neck of the container, an upraised peripheral bead beyond the iiange and engaged by the cap outside its weakened area, and a central resilient portion within the flange raised above the plane of the flange, the central portion of the locking member being formed with at least one vertical wall and a wall sloping upwardly and rearwardly to the top of said vertical wall, the vertical and sloping faces on the projection respectively opposing the vertical and sloping walls on the locking member.

9. A closure for sealing the opening through the neck of a container, which comprises an outer cap member adapted to be applied to the endof the neck by rotation, the cap member having a portion of its top surrounded by a weakened zone, gasket means within the closure engageable with the end of the neck to close the opening, a lockingv member between the top of the cap member and the gasket means and freely rotatable with respect to the container neck when the closure is being applied, the locking member having a central resilient part alignable with the opening in the container neck and a peripheral portion adapted to engage on opposite sides, respectively, the upper surface of the gasket means and the inner surface of the top of the cap member outside of the weakened zone and substantially in alignment with the end of the container neck, and means on the cap member within the weak-r ened zone and on the resilientpart of the locking member co-operable upon counter-rotation of the cap member to rupture the material in the weakened zone, the resilient part of the locking member being movable axially in response to forces applied to it by said co-operating means in rupturing the material in the weakened zone.

10. A closure for sealing the opening through the neck of a container, which comprises an outer cap member adapted to be applied to the end of the neck by rotation, the cap member having a portion of its top surrounded by a weakened zone, gasket means within the closure engageable with the end of the neck to close the opening, a locking member between the top of the cap member and the gasket means and freely rotatable with respect to the container neck when the closure is being applied, the locking member having a central resilient part alignable `with the opening in the container neck and a peripheral portion adapted to engage on opposite sides, respectively, 20

the upper surface of the gasket means and the inner surface of the top of the cap member outside of the weakened zone and substantially in 10 alignment with the end of the container neck, the resilient part being offset from said portion, and means on the cap member within the weakened zone and on the resilient part of the locking member (zo-operable upon counter-rotation of the cap member to rupture the material in the weakened zone, the resilient part of the locking member being movable axially in response to forces applied to it by said co-operating means in rupturing the material in the weakened zone.

EDGEWORTH GREENE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,054,032 Conner et al Sept. 8, 1936 2,054,034 Conner et al Sept. 8, 1936 2,066,390 Cahoon et al Jan. 5, 1937 2,409,846 Greene Oct. 22, 1946