US2352384A - Tin-coated collapsible tube - Google Patents

Description

J. HOCH TINCOATED COLLAPS IBLE TUBE Filed July 12, 1941 INVENTOR (/0171; [7'06]? Mk M . ATTORNEY June 27, 1944.

Patented June 27, 1944 TIN-COATED COLLAPSIBLE TUBE John Hoch, Corona, Long Island, N. Y., assignor to Victor Metal Products Corporation, Brooklyn, N. Y., a corporation of New York Application July 12, 1941, Serial No. 402,116 7 2 Claims.

Thisinvention relates to collapsible tubes and particularly to tin-coated lead tubes.

While such tubes may be extruded by known methods from tin-coated lead slugs, the trimming and threading operations undesirably expose the metallic lead, especially at the neck end thereof, rendering the tube commercially useless for dispensing many substances because of the chemical action of the exposed lead upon the contents, or the action of the contents upon the lead.

Numerous attempts heretofore made to form the tube of two pieces, namely, a tubular body piece and a non-metallic or tin neck piece, have been commercially unsuccessful primarily for the reason that such tubes are not adapted for quantity production or by known methods and are consequently comparatively expensive.

My invention therefor contemplates the provision of a tin-coated lead tube having a neck piece of a suitable molded composition, and of means for adequately securing the molded neck piece to the remainder of the tube inexpensively against accidental detachment of the neck piece, and against possible rotation thereof on the unscrewing of I the cap.

My invention further contemplates the provision of a tube provided with a tin-coated tubular body portion and'tin-coated thicker conical shoulder portion and provided with a molded neck piece adequately securedto the shoulder portion by the distortion of a part of the metal of the shoulder portionv at an areav of the shoulder por-' tion adjacent the neck piece, and by forcing such metal into a suitable recess in the neck piece.

The various objects of the invention will be clear from the description which follows and from the drawing, in which,

Fig. l is a fragmentary front'view and partial section of a two-part tube made in accordance with my invention and prior to the permanent securing of the parts together.

Fig. 2 is a similar view of the finished tube showing the projecting lip on the tube shoulder distorted, forced or spun into the recess formed in the bottom screw threads preformed on the neck part.

- Fig. 3 is a similar view of a modified form of the invention wherein the projecting lip on the tube shoulder is forced into an annular recess in the neck piece, the parts being held in pressed con -v tact by means of a suitable nut, which may be screwed into place tightly enough to cause some distortion of the metal ifdesired.

Fig. 4 is a similar View of another modified form of the invention wherein the neck piece is provided with a screw threaded recess into which the projecting lip of the tube shoulder is forced and showing the parts in the positions assumed thereby prior to the permanent attachment thereof together.

Fig. 5 is a similar view of the finished tube illustrated in Fig. 4 and showing the shoulder portion of the tube forced into place or distorted sufficiently to fill the bottom portion of the threaded recess.

Fig. 6 is a similar view of another modified form of the invention similar to Fig. 3, but wherein the threads at the lower part of the neck piece are omitted and a bayonet lock connection substituted therefor.

Fig. 7 is a bottom plan in section.

In the practical embodiment of the invention shown by way of example and referring particularly to Figs. 1 and 2, the body part ll) of the tube is extruded with a cylindrical tin-coated body portion I l and with an integral conical shoulder 12 thinnest at the point l3 where it joins the portion H and thickest at its inner extremity. The shoulder l2 terminates at its inner peripheral edge in the integral annular tincoated upwardly projecting lip M, which is later operated upon and moved out of the position thereof shown in Fig. 1 to the position shown in view of the same, partly Fig. 2. A recess I5 is provided at the inner extremity of the interior surface I6 of the shoulder, said recess being directly below the lip M of the tube.

In this form of the invention, the non-metallic neck piece ll is molded of suitable non-metallic plastic material with the external cap-engaging threads [8 thereon and with a lowermost annular projection [9 adapted to fit closely into the recess IS. The preformed discharge opening 20 of the neck piece communicates with the interior of the tube. Preferably, the projection I9 is provided with a conical lowermost surface 2| continuous or in alignment with the interior surface I6 of the shoulder.

Said neck piece is suitable for quantity production by automatic or semi-automatic machinery as is the body piece Ill. The pieces 10 and Il are quickly and easily assembled into the position of Fig. 1 wherein the projection I9 tightly fill's the f recess 15, whereafter the excess metal forming the lip M of the shoulder is rolled or spun inwardly to fill completely the recess 23 at the tion without material danger of the tin coating being broken and the lead exposed, since both lead and tin are extremely ductile metals capable of easy distortion by the spinning, rolling or other distorting operation above described in connection with the lip l4. Since said lip is forced inwardly, the outer surface 22 of the shoulder l2 presents the usual appearance seen in collapsible tubes with only a part of the non-metallic neck piece protruding. It will be understood that sufficient friction is developed between the inwardly forced lip l4 and the walls of the recess 23, as well as between the walls of the projection 19 and of the recess l5, to prevent rotation of the neck piece when the tube cap is screwed on or unscrewed from the neck piece. The lip I4 when in its final position also prevents the piece I! from moving downwardly and prevents it from becoming detached or separated from the body piece 18.

In the form of the invention shown in Figs. 3 and 4, a somewhat different form of lip is made on the metallic body piece 25 and a different form of recess in the molded neck piece 26. The recess I may, if desired, be omitted from the conical shoulder 21, and the cylindrical lip 28 of substantial height is substituted for the comparatively short lip I4. The neck piece 26 is formed with two concentric cylinder walls 29 and 38 joined by a top wall and spaced apart sufiiciently to provide the cylindrical annular recess 3| into which the lip 28 may readily be forced or expanded. At the lower end of the wall 38 is provided the external threads 32 projecting below the adjacent part of the inner surface 33 of the shoulder 21 sufficiently to receive the nut 34. Said nut is made of suitable material either of molded composition or of suitable metal. The parts are assembled by forcing the neck piece on to the lip 28, said lip being arranged in the recess 3|, whereafter the nut 34 is screwed tightly on to the threads 32 and with sufiicient force to compress and slightly distort the metal of the shoulder and the lip and thereby to expand said metal sufficiently to completely fill the recess 3| and to force the material of the lip into firm frictional contact with the adjacent surfaces of the walls 29 and 38.

It will be understood, however, that if desired, thelip 23 may fit comparatively loosely in the recess 3| and that the pressure exerted by the nut 34 may be depended on to expand the metal of the lip sufficiently to force said metal into firm frictional contact with the adjacent surfaces of the walls 29 and 38. It will further be understood that by tightening the nut 34 on the threads. 32 sufficiently, the innermost area of the interior shoulder surface 33 may be compressed and distorted to a sufiicient extent to move part of the material of theshoulder 2T upwardly into the recess 3| thereby to secure the neck piece 26 adequately to the shoulder.

In that form of the invention shown in Figs. 6 and '7, the screw threads 32 at the lower end of the neck piece of Figs. 3 and 4 are replaced by a series of circumferentially spaced lugs 48, 4|, there being spaces at 42 between pairs of adjacent lugs. The lugsare arranged below the interior surface 43 of the shoulder 44 and areformed on the inner wall 45 of the molded neck piece 45. The outer wall 41 of said neck piece is provided with screw threads in the same manner as has been described in connection with the outer wall 29 of Fig. 3. The lip 48, similar to the lip 28, is inserted into the recess 49 between the concentric walls 45 and 41. Instead of the nut 34, there is provided a 75 preferably though not necessarily conical washer 58 in the inner edge of which are formed spaced recesses 5| of substantially the same width and depth as the projections or lugs 40. The number of recesses 51 and the spacing thereof is the same as the number of such lugs and the spacing of said lugs. The washer may therefore be readily slipped over the lugs, this being done by registering the lugs 48 with the corresponding recess 5!. Thereafter, the washer 50 is pressed outwardly and axially and rotated to carry the projections 52 thereof over the lugs 40 and thereby to force the washer into pressed contact with the inner surface 43 at the inner portion of said shoulder. Even. comparatively small pressure serves to expand the lip 48 and to cause said lip to fill the recess 49. In order to obtain the desired pressure, the upper surfaces of the lugs 40 or the lower surface of the washer 50 or both, may be suitably bevelled or tapered so as to obtain a cam action causing axial movement of the washer when the washer is rotated to its locking position.

Referring now to the form of the invention shown in Fig. 5, the molded neck piece 55 is provided with the outer threaded wall '56 and the inner wall 5'! on the outer surface of which the external threads 58 are formed. The lip 59 projecting from the shoulder 60 is internally threaded to engage the threads 58. The threading operation, however, removes the tin coating from the inner surface of the lip, but since the resulting exposed lead surface is protected and covered by the threads 58, such exposure of the lead at the threads is immaterial. The inner peripheral portion 6| of the shoulder 50 is preferably below the lower edge of the neck piece in the assembled position of the parts shown in Fig. 4. In such position, however, there is danger that unscrewing the cap might unscrew the neck piece from the li 59 so that a distorting operation is performed upon the shoulder portion 6|. Said operation forces the material of the shoulder portion 6| inwardly and upwardly into the recess 62 forming the lowermost part of the lip-receiving recess 59 and the bottom of the screw threads. The finished tube as shown in Fig. 5, presents a tincoated surface 63 on the interior of the shoulder 60, whereby the contents of the tube cannot reach any exposed lead surface. The walls 56 and 51 being integrally joined by the connecting wall 64, the entire neck piece may readilybe produced in large quantities and assembled with the body piece of the tube rapidly and inexpensively to form a tin-coated tube having a molded neck piece and wherein no lead surfaces are exposed.

It will be seen from the above that I have provided a two piece tube, the neck piece of which is provided with a suitable recess into which excess material provided on the conical shoulder portion of the body piece may easily be forced or expanded, thereby securely to hold the two pieces together to form a single unitary member not likely to become accidentally detached, and hence that the tube is well adapted for comparatively inexpensive commercial quantity production.

While I have shown and described certain specific embodiments of the invention, I do not wish to be understood as limiting myself thereto, but intend to claim the invention as broadly as may be permitted by the appended claims.

I claim:

1. A collapsible tube comprising a cylindrical body part terminating in a conical shoulder having a central opening therein, a cylindrical wall constituting a lip upstanding from the shoulder around the opening, a one piece neckforming member comprising a pair of spaced apart concentric cylindrical walls, one of the concentric walls being arranged inside of and in contact with the inner surface of the lip and extending to a point below the inner surface of the shoulder and into the interior of the body part, the lower end portion of said one wall being externally threaded, the other of the concentric walls being externally threaded to receive a cap and being arranged outside of the lip and in contact with the outer cylindrical surface of the lip and being shorter than the lip and terminating at a point in upward spaced relation to the outer surface of the shoulder whereby the neck-forming member may be forced toward the shoulder, and an annular wall joining the upper ends of the concentric walls and in firm engagement with the upper edge of the lip, and a separate nut screwed on to the threaded lower part of said one wall and acting against the inner surface of the tube shoulder to draw the neck-forming member downwardly until the annular wall is pressed firmly against the upper edg of the lip to seal the joint therebetween, said nut when further screwed against the shoulder then distorting and expanding the lip between the concentric walls to fill the space between said walls and thereby to provide an additional seal between the neck-forming member and the lip.

2. A collapsible tube comprising a conical shoulder having an opening therein, an upstanding cylindrical distortable lip surrounding the opening, a one piece neck-forming member having a pair of spaced apart concentric walls joined at their tops by an integral annular wall, the outer of the concentric walls being externally threaded to receive a cap and terminating at a point above the shoulder to permit the neck-forming member to be forced downwardly along the lip, the inner of said concentric walls extending downwardly below the shoulder and being externally threaded at its lower end, and a separate nut on said lower end screwed against the inner surface of the shoulder and drawing the neck-forming member downwardly until the annular wall is in sealing contact with the upper edge of the lip and said lip is expanded sufficiently to fill the space between the concentric walls.

JOHN HOCH.

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