Thread Forming Apparatus And Associated Method

Abstract

A thread forming apparatus includes an outer ring having a plurality of projections disposed around an inner periphery thereof, the outer ring being structured to remain stationary, an inner ring including a plurality of recesses disposed around an outer periphery thereof, the inner ring being structured to be moved radially toward a sidewall of a can body positioned between the outer ring and the inner ring and rotated against the sidewall and the projections. The rotation against the can sidewall and the projections causes can material to flow into the recesses and form a plurality of threads around the inner circumference of the can body. An actuator is coupled to the outer ring and the inner ring and structured to hold the outer ring stationary and the inner ring radially and rotate the inner ring against the sidewall.

Claims

1. A thread forming apparatus structured to form a plurality of threads around a circumference of a can body having a base and a sidewall extending from the base, the thread forming apparatus comprising: an outer ring including a plurality of projections disposed around an inner periphery of the outer ring, the outer ring being structured to remain stationary; an inner ring including a plurality of recesses disposed around an outer periphery of the inner ring; and an actuator coupled to the outer ring and the inner ring, wherein when the sidewall of a can body is positioned between the inner ring and the outer ring the inner ring is structured to be moved radially toward the sidewall of the can body and rotated against the sidewall and the projections, the rotation against the can sidewall and the projections causing can material to flow into the recesses and form the plurality of threads around the inner circumference of the can body, and wherein the actuator is structured to hold the outer ring stationary and move radially and rotate the inner ring against the can sidewall.

2. The apparatus of claim 1, wherein when the sidewall of a can body is positioned between the inner ring and the outer ring, upon actuation the inner ring is moved outward and starts to be rotated against the inner periphery of the outer ring, the rotation causing the inner ring to press against the can sidewall and projection against the can sidewall and a projection, and wherein the pressing causes the can material to flow into a recess and form an internal thread on the can sidewall.

3. The apparatus of claim 2, wherein upon completion of formation of the internal thread, the inner ring rolls away from the internal thread and continues to be rotated to form remaining internal threads one by one.

4. The apparatus of claim 3, wherein upon completion of forming the remaining internal threads, the can body is released from the apparatus.

5. The apparatus of claim 4, wherein the inner ring and the outer ring is structured to keep the can body stationary until the release.

6. A thread forming apparatus structured to form a plurality of threads around a circumference of a can body having a base and a sidewall extending from the base, the thread forming apparatus comprising: an outer ring including a plurality of recesses disposed around an inner periphery of the outer ring, the outer ring being structured to be moved radially toward the can body such that one end of each recess contacts the outer circumference of the can body; an inner ring including a plurality of projections disposed around an outer periphery of the inner ring, the inner ring being structured to be moved among the recesses in a pattern and press the projections into the can sidewall and respective recesses, pressing the projections into the respective recesses causing can material to flow into the respective recesses and form the threads around the outer circumference of the can body; and an actuator coupled to the outer ring and the inner ring and structured to move radially the outer ring and the inner ring to form the plurality of threads in the pattern.

7. The thread forming apparatus of claim 6, wherein the pattern is of a star shape.

8. The thread forming apparatus of claim 6, wherein the plurality of recesses are disposed equidistant around the inner periphery of the outer ring.

9. The thread forming apparatus of claim 6, wherein the plurality of projections are disposed equidistant around the outer periphery of the inner ring.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which:

[0011] FIG. 1 is a partially schematic, perspective view of a can body positioned with a portion thereof within an example thread forming apparatus in accordance with a non-limiting, example embodiment of the disclosed concept;

[0012] FIG. 2 is a front elevation view of the portion of the can body, shown in section, positioned within the exemplary thread forming apparatus of FIG. 1 in accordance with a non-limiting, example embodiment of the disclosed concept;

[0013] FIG. 3 is a perspective view of a thread-formed can body being released from the example thread forming apparatus of FIGS. 1 and 2 in accordance with a non-limiting, example embodiment of the disclosed concept;

[0014] FIG. 4 is a front elevation view of the example thread forming apparatus of FIGS. 1-3, shown without a can body;

[0015] FIG. 5 is another front view of the example thread forming apparatus of FIGS. 1-4 shown with an inner ring moved radially toward the inner periphery of an outer ring in accordance with a non-limiting, example embodiment of the disclosed concept;

[0016] FIGS. 6-8 are detail views of the area 150 of FIG. 5 illustrating thread forming motions of the example thread forming apparatus of FIGS. 1-5;

[0017] FIG. 9 is a perspective view of a plurality of threads formed around the inner circumference of a sidewall of a can body by the example thread forming apparatus of FIGS. 1-8 in accordance with a non-limiting, example embodiment of the disclosed concept;

[0018] FIG. 10 is a front view of an example thread forming apparatus in accordance with another non-limiting, example embodiment of the disclosed concept; and

[0019] FIG. 11 illustrates forming a plurality of equidistant threads around the outer circumference of a can body in a star pattern by the example thread forming apparatus of FIG. 10 in accordance with a non-limiting, example embodiment of the disclosed concept.

DETAILED DESCRIPTION OF THE INVENTION

[0020] Directional phrases used herein, such as, for example, clockwise, counterclockwise, left, right, top, bottom, upwards, downwards and derivatives thereof, relate to the orientation of the elements shown in the drawings and are not limiting upon the claims unless expressly recited therein.

[0021] As used herein, the singular form of a, an, and the include plural references unless the context clearly dictates otherwise.

[0022] As used herein, structured to [verb] means that the identified element or assembly has a structure that is shaped, sized, disposed, coupled and/or configured to perform the identified verb. For example, a member that is structured to move is movably coupled to another element and includes elements that cause the member to move or the member is otherwise configured to move in response to other elements or assemblies. As such, as used herein, structured to [verb] recites structure and not function. Further, as used herein, structured to [verb] means that the identified element or assembly is intended to, and is designed to, perform the identified verb. Thus, an element that is merely capable of performing the identified verb but which is not intended to, and is not designed to, perform the identified verb is not structured to [verb].

[0023] As used herein, associated means that the elements are part of the same assembly and/or operate together or act upon/with each other in some manner. For example, an automobile has four tires and four hub caps. While all the elements are coupled as part of the automobile, it is understood that each hubcap is associated with a specific tire.

[0024] As used herein, the statement that two or more parts or components are coupled shall mean that the parts are joined or operate together either directly or indirectly, i.e., through one or more intermediate parts or components, so long as a link occurs. As used herein, directly coupled means that two elements are directly in contact with each other. As used herein, fixedly coupled or fixed means that two components are coupled so as to move as one while maintaining a constant orientation relative to each other. As used herein, adjustably fixed means that two components are coupled so as to move as one while maintaining a constant general orientation or position relative to each other while being able to move in a limited range or about a single axis. For example, a doorknob is adjustably fixed to a door in that the doorknob is rotatable, but generally the doorknob remains in a single position relative to the door. Further, a cartridge (nib and ink reservoir) in a retractable pen is adjustably fixed relative to the housing in that the cartridge moves between a retracted and extended position, but generally maintains its orientation relative to the housing. Accordingly, when two elements are coupled, all portions of those elements are coupled. A description, however, of a specific portion of a first element being coupled to a second element, e.g., an axle first end being coupled to a first wheel, means that the specific portion of the first element is disposed closer to the second element than the other portions thereof. Further, an object resting on another object held in place only by gravity is not coupled to the lower object unless the upper object is otherwise maintained substantially in place. That is, for example, a book on a table is not coupled thereto, but a book glued to a table is coupled thereto.

[0025] As used herein, the statement that two or more parts or components engage one another means that the elements exert a force or bias against one another either directly or through one or more intermediate elements or components. Further, as used herein with regard to moving parts, a moving part may engage another element during the motion from one position to another and/or may engage another element once in the described position. Thus, it is understood that the statements, when element A moves to element A first position, element A engages element B, and when element A is in element A first position, element A engages element B are equivalent statements and mean that element A either engages element B while moving to element A first position and/or element A either engages element B while in element A first position.

[0026] As used herein, correspond indicates that two structural components are sized and shaped to be similar to each other and may be coupled with a minimum amount of friction. Thus, an opening which corresponds to a member is sized slightly larger than the member so that the member may pass through the opening with a minimum amount of friction. This definition is modified if the two components are to fit snugly together. In that situation, the difference between the size of the components is even smaller whereby the amount of friction increases. If the element defining the opening and/or the component inserted into the opening are made from a deformable or compressible material, the opening may even be slightly smaller than the component being inserted into the opening. With regard to surfaces, shapes, and lines, two, or more, corresponding surfaces, shapes, or lines have generally the same size, shape, and contours.

[0027] As used herein, the term number shall mean one or an integer greater than one (i.e., a plurality). That is, for example, the phrase a number of elements means one element or a plurality of elements. It is specifically noted that the term a number of [X] includes a single [X].

[0028] As used herein, about in a phrase such as disposed about [an element, point or axis] or extend about [an element, point or axis] or [X] degrees about an [an element, point or axis], means encircle, extend around, or measured around. When used in reference to a measurement or in a similar manner, about means approximately, i.e., in an approximate range relevant to the measurement as would be understood by one of ordinary skill in the art.

[0029] As used herein, an elongated element inherently includes a longitudinal axis and/or longitudinal line extending in the direction of the elongation.

[0030] As used herein, generally means in a general manner relevant to the term being modified as would be understood by one of ordinary skill in the art.

[0031] As used herein, substantially means for the most part relevant to the term being modified as would be understood by one of ordinary skill in the art.

[0032] As used herein, at means on and/or near relevant to the term being modified as would be understood by one of ordinary skill in the art.

[0033] As the need for resealable cans increases, metallic beverage containers (e.g., without limitation, cans) with threaded closures that can be used to reseal the containers have been developed. However, the thread forming devices for the containers with the external threads are expensive and not conducive to high-speed manufacture. Example embodiments of thread forming apparatus in accordance with the disclosed concept achieve radial and rotating motion of an inner die to place threads (e.g., recesses, projections, or other thread forms) at a plurality of points along the circumference of the sidewalls of can bodies at a very high speed, resulting in a high-throughput manufacturing of the threaded, reusable metallic beverage containers, the high-throughput being substantially higher than the throughput by the existing thread forming devices for metallic beverage containers. As such, the example thread forming apparatus resolve the manufacturing inefficiencies and high costs associated with the existing thread forming devices for metallic beverage containers. Further, by pressing intermittent threads in top portions of metallic beverage containers, the example thread forming apparatus in accordance with the disclosed concept provide the containers a similar appearance to the appearance of the existing resealable beverage containers that require threads at the top of the containers as well as threaded inserts.

[0034] FIGS. 1-8 illustrate an exemplary thread forming apparatus 100 in accordance with a non-limiting, example embodiment of the disclosed concept. The example thread forming apparatus 100 is structured to form a plurality of threads 11 around a circumference of a can body 10. The can body 10 has a base 12 and a can sidewall 13 extending from the base 12 in parallel to a central axis 3 of the can body 10 and defining an interior 15 (see FIG. 9) of the can body 10 that is structured to store a content therein. The can sidewall 13 has a rim 14 forming an opening to the interior 15. The example thread forming apparatus is structured to form the plurality of threads 11 around the circumference of the sidewall 13, of the can body 10, typically near the rim 14.

[0035] The thread forming apparatus 100 is structured to form threads 11 at multiple points around the circumference of the sidewall 13 of the can body 10 and includes an outer ring 110, an inner ring 130 and one or more actuators 102. The outer ring 110 has a plurality of projections 120 disposed around, and projecting radially inward from, an inner periphery 112 thereof. The inner ring 130 has a plurality of recesses 140 disposed around, and extending radially inward to, an outer periphery 132 thereof. While FIGS. 2 and 4-6 show that the outer ring 110 and the inner ring 130 include six equidistant projections 120 and six equidistant recesses 140, respectively, so as to form six equidistant internal threads 11 around the inner circumference of the can body 10 as shown in FIG. 10, it is to be appreciated that this is for illustrative purposes only, and thus the rings 110,130 may have more or less projections and recesses to form more or less threads 11 as appropriate for particular applications without departing from the scope of the disclosed concept. The one or more actuators 102 are coupled to the outer ring 110 and the inner ring 130 and are structured to hold the outer ring 110 stationary and radially move and rotate the inner ring 130 against the interior of the sidewall 13 of the can body 10. In some example embodiments, the one or more actuators 102 may move the outer ring 110 radially for aligning the thread forming apparatus 100 and the can body 10 for forming threads around the circumference of the sidewall 13 of the can body 10. While FIG. 1 shows one actuator 102, this is for illustrative purposes only, and it will be understood that multiple actuators 102 may be employed without departing from the scope of the disclosed concept. For example, the outer ring 110 and the inner ring 130 may be held stationary or moved radially by a common actuator or individual actuators may be associated with the outer ring 110 and the inner ring 130. The one or more actuators 102 may be any suitable actuating mechanism (e.g., without limitation, cams and cam followers). The one or more actuators 102 are omitted from FIGS. 2-8 for economy of disclosure, but it will be understood that one or more actuators 102 may be employed in any of the disclosed embodiments.

[0036] Formation of the internal threads 11 will now be described with reference to FIGS. 2 and 4-8. While FIGS. 4-8 depict chronological movements of the outer and inner rings 110,130 without the can body 10 being positioned between the outer and inner rings 110,130, the movements are described as if the can body 10 is positioned therebetween for clarity and completeness of disclosure. As shown in FIG. 4, initially, the outer ring 110 and the inner ring 130 are coaxial and radially separate from each other. The rim 14 and adjoining sidewall 13 of can body 10 may then be moved to be inserted between the outer ring 110 and the inner ring 130, e.g., via a pusher pad (not shown) such as commonly known in the art. Alternatively, the can body 10 may rest on, e.g., without limitation, a pusher pad (not shown), and the outer ring 110 and the inner ring 130 may be moved axially in parallel to the central axis 3 of the can body 10 so as to receive the can body 10 therebetween. That is, the outer ring 110 may be moved axially to encompass the outer circumference of the sidewall 13 of the can body 10 and the inner ring 130 may be inserted within the interior 15 of the can body 10. Upon positioning the can body 10 between the outer ring 110 and the inner ring 130 (see FIG. 2), the thread forming apparatus 100 is actuated.

[0037] Upon actuation, the inner ring 130 is moved radially toward the can sidewall 13 and starts to be rotated clockwise against the inner periphery 112 of the outer ring 110 (and thus, the interior of the sidewall 13 of the can body) and a projection 120 (see FIGS. 5 and 6) of the outer ring 110. The inner ring 130 continues to be rotated such that the projection 120 and the recess 140 are aligned as shown in FIG. 6. In such example embodiment, each projection 120 of the outer ring 110 has a male thread form geometry (e.g., a protrusion, a protuberance, a ledge or other thread form geometry), and each recess 140 of the inner ring 130 has a female thread form geometry that is a negative of the male thread form geometry of the projection 120, however, it is to be appreciated that such geometries may be generally reversed to form external threads without varying from the scope of the disclosed concept. With the sidewall 13 disposed between the projection 120 and the recess 140, pressing against the sidewall 13 and the projection 120 causes the can material to flow into the recess 140 and form an internal thread 11 (see FIGS. 3 and 9) in the sidewall 13. The internal thread 11 projects inward from the sidewall 13 and has a shape corresponding to the projection 120 and the recess 140. Upon completion of forming the internal thread 11, the inner ring 130 rolls away from the newly formed internal thread 11 and continues to be rotated to form the next internal thread 11 adjacent to the newly formed thread 11 in the sidewall 13 of the can body 10. The inner ring 130 continues to be rotated and presses against the sidewall 13 and the remaining projections 140 until the last internal thread 11 of the plurality of internal threads 11 has been formed. Both the outer ring 110 and the can body 10 remain stationary during the formation of the internal threads 11. While FIGS. 5-8 show the inner ring 130 being rotated clockwise, this is for illustrative purposes only, and thus the inner ring 130 may be rotated counterclockwise as appropriate without departing from the scope of the disclosed concept. Upon forming all of the internal threads 11 in the sidewall 13 of the can body 10, the thread forming apparatus 100 releases the can body 10.

[0038] FIG. 3 shows the thread forming apparatus 100 releasing the can body 10 upon forming all of the internal threads 11 around the inner circumference of the sidewall 13 of the can body 10. To release the can body 10, the inner ring 130 is moved radially away from the can body 10, allowing the newly formed internal threads 11 of the can body 10 to be separated from the projections 120 and the recesses 140. In the position shown in FIG. 3, upon such separation, the can body 10 can be moved away from the thread forming apparatus 100, the thread forming apparatus 100 can be moved away from the can body 10, or both can be moved away from each other.

[0039] FIGS. 10-11 illustrate another example thread forming apparatus 200 in accordance with another non-limiting, example embodiment of the disclosed concept. The example thread forming apparatus 200 is similar to the thread forming apparatus 100 of FIGS. 1-8 except that the outer ring 210 has a plurality of equidistant recesses 241-246 (of the same geometry) around the inner periphery 212 thereof, the inner ring 230 has a plurality of equidistant projections 221-226 (of the same geometry) around the outer periphery 232 thereof, the inner ring 230 is moved to cross the interior 15 of a can body 10 diagonally or substantially diagonally in a star pattern, and the outer and inner rings 210 and 230 together form a plurality of equidistant external threads (not shown) around the outer circumference of the sidewall 13 of a can body 10. Thus, overlapping description for similar components has been omitted herein for brevity. Each external thread projects outward from the sidewall 13 of the can body 10 and has a shape corresponding to one of the projections 221-226 and one of the recesses 241-246. FIG. 10 shows the outer ring 210 and the inner ring 230 in the initial position when the apparatus 200 is not actuated to form the external threads on a can body 10.

[0040] Formation of the external threads in a sidewall 13 of a can body 10 is described with reference to FIG. 11. FIG. 11 illustrates chronological movements of the inner ring 230 generally in a star pattern 201 for forming equidistant external threads around the outer circumference of the sidewall 13 of a can body 10 (not shown in FIG. 11) that would be present between the outer ring 210 and inner ring 230 similar to as shown in FIG. 2. Upon positioning the can sidewall 13 between the outer and inner rings 210 and 230, the inner ring 230 is moved radially toward the can sidewall 13 and a first recess 241, pressing a first projection 221 into the can sidewall 13. Simultaneously, the outer ring 210 is moved radially toward the can sidewall 13 such that one end 241a of the first recess 241 contacts the outer circumference of the sidewall 13 of the can body 10. The inner ring 230 then rolls against the can sidewall 13 and the inner periphery 212 of the outer ring 210, pressing the first projection 221 into the first recess 241. With the can sidewall 13 disposed between the first projection 221 and the first recess 241, pressing the first projection 221 into the first recess 241 causes the can material to flow into the first recess 241 and form a first external thread at point 1 of the can sidewall 13. Upon forming the first external thread, the inner ring 230 rolls out of the first recess 241, allowing the first external thread to separate from the first recess 241. As such, a projection rolls through a recess similarly to a heel-to-toe rolling of a human foot.

[0041] Upon such separation, the inner ring 230 is moved away from the first external thread at point 1 and the first recess 241 and continues to be moved diagonally or substantially diagonally in the star pattern 201 in order to form remaining external threads around the outer circumference of the can body 10. That is, the inner ring 230 is moved diagonally away from the first external thread at point 1 to form a second external thread at an opposite point 2 on the sidewall 13 of the can body 10 using second projection 222 and second recess 242. Upon forming the second external thread, the inner ring 230 is moved substantially diagonally away from the second external thread at point 2 and the second recess 242 to form a third external thread at a substantially opposite point 3 on the sidewall 13 of the can body 10 using third projection 223 and third recess 243. Upon forming the third external thread, the inner ring 230 is moved diagonally away from the third external thread at point 3 and the third recess 243 to form a fourth external thread at an opposite point 4 on the sidewall 13 of the can body 10 using fourth projection 224 and fourth recess 244. Upon forming the fourth external thread, the inner ring 230 is moved substantially diagonally away from the fourth external thread at point 4 and the fourth recess 244 to form a fifth external thread at a substantially opposite point 5 on the sidewall 13 of the can body 10 using fifth projection 225 and fifth recess 245. Upon forming the fifth external thread, the inner ring 230 is moved diagonally away from the fifth external thread at point 5 and the recess 245 to form the last external thread at an opposite point 6 on the sidewall 13 of the can body 10 using last projection 226 and last recess 246. Upon forming the last external thread, the inner ring 230 is radially moved away from the last external thread toward the central axis 3 and releases the can body 10 from the thread forming apparatus 200.

[0042] In some example embodiments, the outer ring may include a plurality of equidistant projections and the inner ring may include a plurality of equidistant recesses. In those example embodiments, the inner ring is still moved substantially diagonally within the interior 15 of the can body 10 in the star pattern, and the outer and inner rings together form a plurality of equidistant internal threads extending inward from the sidewall 13 of the can body 10.

[0043] While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the disclosed concept which is to be given the full breadth of the claims appended and any and all equivalents thereof.

[0044] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word comprising or including does not exclude the presence of elements or steps other than those listed in a claim. In any device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The word a or an preceding an element does not exclude the presence of a plurality of such elements. The mere fact that certain elements are recited in mutually different dependent claims does not indicate that these elements cannot be used in combination.