Patent Abstract:
A knitting needle has multiple segments, at least one of which is relatively non-rigid, wherein the segments can be combined to produce a needle that is sufficiently rigid to be used for knitting, while also having diminished usefulness as a weapon. In three major classes of embodiments, one of the segments fits inside the other in a telescoping manner, one of the segments wraps around the other, or the two segments can fit together in some sort of slotted fashion. There may be one or more engineered points of structural failure. Segments can be held together frictionally, magnetically, threadably, using a snap or twist and lock fitting, or in any other suitable manner. Contemplated segments can have any suitable composition, including especially a bendable plastic or a foam rubber.

Full Description:
PRIORITY CLAIM 
     This application claims priority to provisional patent application Ser. No. 61/372,534 filed Aug. 11, 2010. 
    
    
     FIELD OF THE INVENTION 
     The field of the invention is knitting needles technologies. 
     BACKGROUND 
     Modern air travel security sometimes restricts passengers from taking on board simple devices that allow them to pass the time engagingly. For example, knitting needles are prohibited on flights throughout countries in the European Union, and in the United States, the transportation airport security (TSA) officers can confiscate knitting needles at their discretion if they think the needles could be used as weapons. 
     One problem is that commonly used knitting needles, whether hollow or solid, tend to be quite rigid. For example, traditional bamboo, wooden, solid metal or plastic needles are all likely to be too rigid to pass muster under current TSA standards. 
     One could conceivably use multiple segments to solve the rigidity problem, but from the Applicants perspectives, none of the multiple segmented knitting needles solves that problem. For example, U.S. Pat. No. 2,094,262 to Burnham, describes a knitting needle shaft with a detachable point, but both the shaft and the detachable point are rigid, and would tend to be prohibited from use on airplanes. 
     It is also conceivable to hollow out the shaft to make it more flexible, but to date hollow shafted knitting needles tend to utilize the lumen in a manner that has nothing to do with rigidity. For example, U.S. Pat. No. 482,490 to Miller, describes a rigid crocheting needle with a hollow shaft adapted to fit a knitting needle within the hollow shaft. In Miller the addition of the second needle to the hollow compartment has no bearing on the functionality of the needle. The hollow compartment merely functions as a storage cavity. Even further, the outer (crocheting needle) is quite rigid. 
     Burnham and Miller and all other extrinsic materials discussed herein are incorporated by reference in their entirety. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply. 
     Unless the context dictates the contrary, all ranges set forth herein should be interpreted as being inclusive of their endpoints and open-ended ranges should be interpreted to include only commercially practical values. Similarly, all lists of values should be considered as inclusive of intermediate values unless the context indicates the contrary. 
     Thus, there is still a need for a knitting needle that has both flexible and rigid configurations. 
     SUMMARY OF THE INVENTION 
     The inventive subject matter provides apparatus, systems and methods in which a knitting needle has multiple segments, at least one of which is relatively non-rigid, wherein the segments can be combined to produce a needle that is sufficiently rigid to be used for knitting. 
     All suitable combinations of segments are contemplated. In three major classes of embodiments, one of the segments fits inside the other (e.g., in a telescoping manner), one of the segments wraps around the other, or the two segments can fit together in some sort of slotted fashion. The segments can be held together frictionally, magnetically, threadably, using a snap or twist and lock fitting, or in any other suitable manner. The desired additional rigidity for knitting can thus be accomplished by the segments mutually supporting each other, or by some other manner such as pneumatic pressure. 
     Contemplated segments can have any suitable composition, including especially a bendable plastic or a foam rubber. Most likely the outer surface of commercially suitable combinations will have a smooth coating, which can advantageously comprise at least one of an elastomeric polymer, a paint, a milk protein or a sugar cane protein. 
     Contemplated segments and coupling structures can advantageously include one or more engineered points of structural failure such that the needles can collapse or disassemble when they are pressed in a stabbing motion against a structure, as for example against a human. 
     Where a segment has an open end, that end can be closed by an end cap, or even by a cable that couples the open ends of two needles. 
     Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is a side view of one embodiment of a knitting needle. 
         FIG. 2   a  is a side view of one preferred embodiment of the knitting needle of  FIG. 1 , comprising a flexible shealth and a foam rod. 
         FIG. 2   b  is a side view of the knitting needle of  FIG. 2   a , showing an angle of deflection when the needle is attached to a support. 
         FIG. 3  is a side view of one embodiment of the knitting needle of  FIG. 1 , comprising a vulcanized rubber rod coated with starch. 
         FIG. 4   a  is a side view of one embodiment of a telescopic knitting needle having two concentric segments. 
         FIG. 4   b  is a side view of two telescopic knitting needles coupled together for circular knitting. 
         FIG. 4   c  is a side view of one embodiment of a telescopic knitting needle having three concentric segments. 
         FIG. 5   a  is a side view of one embodiment of a knitting needle comprising two threadably coupled segments. 
         FIG. 5   b  shows various embodiments of coupling mechanisms for knitting needle segments. 
         FIG. 6   a  shows perspective views of slotted knitting needle segments that mate in a finger joint fashion. 
         FIG. 6   b  shows cross sections for two alternative designs for slotted knitting needle segments. 
         FIG. 7  is a side view of one embodiment of a knitting needle having a semi-rigid segment and a non-rigid segment. 
         FIG. 8   a  is a side view of a knitting needle with engineered stress fractures and perforations. 
         FIG. 8   b  is a side view of a break-away knitting needle with engineered stress fractures and perforations. 
         FIG. 9  is a perspective view of a male adaptor comprising a threaded shaft and having stress fractures and perforations. 
     
    
    
     DETAILED DESCRIPTION 
     In  FIG. 1 , a multi-segmented knitting needle  100  generally comprises a non-rigid segment  110  and a second segment  120 , which is preferably semi-rigid. The non-rigid segment  110  has a distal end  112  (distal because it tends to point somewhat away from the torso of the user) and a proximal end  114  (proximal because it tends to point somewhat away towards the torso of the user). A needle point  116  is disposed at the distal end  112 . The second segment  120  can be non-rigid or semi-rigid, and is preferably constructed to support the non-rigid segment and to add to the rigidity of the knitting needle. In this particular example, the second segment  120  has a distal end  122  and a proximal end  124 . A needle point  116  is disposed at the terminal end  122 . 
     In a preferred embodiment the non-rigid segment  110  is a flexible sheath having a lumen  111 , and segment  120  is a foam rod that is configured to be slidably inserted into the first segment  110  to form the needle  100 , as illustrated in  FIG. 2   a . In this embodiment segment  120  slides along the full length of the non-rigid segment  110 . 
     As used herein, the term “non-rigid” as applied to a segment means that the segment has sufficient flexibility such that when one end is anchored horizontally to a fixed support, the opposite end can bend under its own weight by a deflection higher than 30°. More preferably the deflection angle is in the range of 20° to 30°. Even more preferably the deflection angle is in the range of 10° to 20°. In  FIG. 2   b  segment  110  is non-rigid, since it bends under its own weight by approximately 23° when attached to support  115 . 
     Contemplated non-rigid segments can be constructed from any suitable materials that allow sufficient flexibility for the structure being composed. Contemplated materials include natural and synthetic fibers, polymers or combination thereof (e.g., elastomers, epoxy resins, celluloids, urethanes, silicones, foam rubber, vulcanized rubber tubing, and bendable plastic). Contemplated structures include rolled paper, rolled paper impregnated with a natural polymer (e.g. natural latex) and/or a synthetic polymer (e.g. synthetic rubber), filaments, and molded, extruded or pultruded objects. 
     As used herein, the term “semi-rigid” as applied to a segment means that the segment has sufficient flexibility such that when one end is anchored horizontally to a fixed support, the opposite end will bend under its own weight by a deflection angle of 1° to 30°, inclusive. More preferably the deflection angle is in the range of 2° to 20° inclusive. Even more preferably the deflection angle is in the range of 5° to 10° inclusive. 
     A semi-rigid second segment that can be constructed from the same types of materials contemplated for the construction of the non-rigid segment. Additionally, the materials can be hardened to a degree that will result in the formation of a non-threatening needle. Material hardening techniques are known in the art. For example, foam rubber can be constructed to be flexible or stiff depending on the degree of cross-linkers used and the configuration of the cell structure. In another example, a bendable plastic can be hardened by curing with UV radiation. Yet in another example, the properties of vulcanized rubber are known to be influenced by details of the compounding of the base polymers, cross-linking agents, accelerators, fillers etc. The potential for “tailoring&#39; the segment to a specific flexibility is essentially limitless. 
     It is contemplated that non-rigid and semi-rigid materials could be hardened to have a durometer number higher than 30 but lower than 90 on the A scale. More preferably, such materials could be hardened to have a durometer higher than 40 but lower than 60 on the A scale. For reference, the rubber band has durometer number of 25 and the ebonite rubber has a durometer number of 100, on the same scale. A break-away needle is preferably relatively rigid, with engineered break lines (i.e. engineered points of failure) that would tend to preclude the use of such a needle as a significant weapon. Where a needle according to aspects of the present inventive subject matter comprises a solid rubber without break lines, preferred needles would preferably have a relatively low durometer of no more than 25. 
     Durometer is one of several measures of the hardness of a material. Hardness can be defined as a material&#39;s resistance to permanent indentation. There are several scales of durometer, used for materials with different properties. The two most common scales, using slightly different measurement systems, are the ASTM D2240 type A and type D scales. The A scale is for softer plastics, while the D scale is for harder ones. However, the ASTM D2240-00 testing standard calls for a total of 12 scales, depending on the intended use; types A, B, C, D, DO, E, M, O, OO, OOO, OOO-S, and R. Each scale results in a value between 0 and 100, with higher values indicating a harder material 
     As used herein, the term “rigid” as applied to a segment means that when one end is anchored horizontally to a fixed support, the opposite end will bend under its own weight by a deflection angle of less or equal to than 1°. A relatively rigid will have a deflection angle in the range of 1° to 5°. By way of example, commercially available needles are constructed from materials (e.g. casein, metal, and plastic) and in such manner that they are relatively rigid. 
     Contemplated segments can be hollow or solid. Such segments can be coated to impart a smooth surface suitable for knitting. Coating materials comprise natural polymers such that proteins, carbohydrates, natural latex, synthetic polymers such that elastomers, epoxy resins, celluloids, enamels, lacquers, urethanes, silicones, synthetic rubber, paint. For example a segment constructed out of rolled paper can be coated with at least one of a milk protein and a sugar cane protein. Another example is a segment constructed from vulcanized rubber that can be coated with a fine powder such as starch  318  shown in  FIG. 3 . Other contemplated coatings can be multi-component, i.e, they can be formed using at least two of the suitable coatings. 
     In  FIG. 3 , the needle  300  comprises a non-rigid segment  310 , a coating  318 , a knitting tip  316  and a semi-rigid segment  320 . In this embodiment, segment  320  is configured to slidably insert and fasten into a short section of the proximal end of the non-rigid segment  310 . The second segment comprises a pneumatic device  328  that can introduce pressurized air to stiffen the non-rigid segment  310 . 
       FIG. 4   a  generally comprises telescopically linked first and second segments  410 ,  420 , and end cap  440 , and an optional cable or other flexible member  460 . As shown, first segment  410  is concentric about second segment  420 , although all other suitable non-concentric telescoping arrangements are also contemplated. Here, both first and second segments are non-rigid, but their combination produces a semi-rigid knitting needle  400 . 
     End cap  440  is secured at the proximal end of the second segment  420 . Such cap can advantageously prevent stitches from slipping from the needle. The cap  440  is preferably constructed from a light weight material, as for example a durable plastic. The cap can advantageously have a blunt end similar to an eraser attached to the end of the pencil, and can be removably attached to the proximal end of the second segment  420  in any suitable manner (e.g., threaded, slided etc.) 
     Flexible member  460  is optional, and when present can be coupled to at least one of the end cap  440  and the proximal portion of the second segment  420 . Contemplated flexible members include a plastic or other cable that can be used for circular knitting. 
       FIG. 4   b  represents a knitting system  200  where the needle  400  described in  FIG. 4   a  is coupled to a second needle  400  using the flexible member  460 . It can be appreciated that needles assembled in any of the contemplated configurations described herein, can be coupled in a similar manner to allow circular knitting. 
     In  FIG. 4   c  the knitting needle  401  further comprises first and second segments described above, and a third segment  430  nested within, and configured to be telescoping relative to, the second segment. In this embodiment all three segments can be non-rigid, and the combination of the three segments can form a semi-rigid functional knitting needle. Furthermore, the additional nested segment  430  can cooperate to provide an adjustable length for the needle. 
       FIG. 5   a  generally comprises threadably coupled first and second segments,  510 ,  520 , a thread adaptor  530 , an end cap  540 , and an optional cable or other flexible member  560 . In this embodiment, the first segment  510  is semi-rigid and the second  520  can be constructed from a non-rigid material that deforms when stabbed against a head or other portion of a body, yet have enough rigidity to manipulate the yarn. For example, the second segment  520  can be a rubber type pencil eraser with a coated surface to allow smooth knitting. 
     Contemplated segments can be held together frictionally, magnetically, threadably, adhesively, using a snap or twist and lock fitting, or in any other suitable manner that composes the functional needle.  FIG. 5   b  illustrates some of these mechanisms, specifically a snap fitting  531 , magnet  532 , twist and lock mechanism  533 , and finger joint mechanism  534 . 
     In  FIG. 6   a , the two segments that form the needle  600  are slotted, and mate in a finger joint fashion. In that manner, segments  610  and  620  interlock lengthwise to form a cylindrical needle with a cross section  630 . In this embodiment the two segments can both be non-rigid, or one non-rigid and the other semi-rigid.  FIG. 6   b  depicts alternative designs having the cross sections  631 ,  632  shown. 
     Yet in another embodiment shown in  FIG. 7 , the second segment  720  has the knitting tip  716  disposed on the distal end. Here, segment  720  is semi-rigid and the first segment  710  is non-rigid and wrapped around the second segment to form the knitting needle  700 . For example, the second segment can be a rubber pencil and the first segment can be coated paper. Furthermore the rubber pencil can have a longitudinal split  722  to allow insertion of a coated paper for rolling around the pencil to create a smooth surface. 
     Contemplated needles can advantageously include one or more engineered points of structural failure that allow the needles to collapse or disassemble when they are used in a stabbing motion against a solid or semi-solid structure, as for example against a human. All manner of commercially feasible points of structural failure are contemplated, including for example perforation and stress fractures. 
     Such points of structural failure can be located in any suitable portion or portions of a needle, including in any one or more of the segments and/or coupling mechanisms. For example in  FIG. 8   a , the needle  800  generally comprises first and second segments  810  and  820  and engineered stress fractures  812  and engineered perforations  814  are longitudinally incorporated into the needle segment  820 . In  FIG. 8   b , the break-away needle  860  comprises a shaft  830  having engineered stress fractures  812  and engineered perforations  814  incorporated into the shaft  830 . 
       FIG. 9  shows engineered points of structural failure, stress fractures  920  and perforations  930 , that are disposed on a threaded shaft  910  used to couple adjacent needle segments. In this particular example the shaft is used in a male to male adaptor  900 . Engineered points of structural failure can additionally or alternatively be introduced to weaken the coupling mechanism by intentionally altering the size of various components. For example, the distance between the top point of the thread, also known as the crest  940 , and the bottom point of the thread, also known as the root  950 , can be reduced, and/or the distance between adjacent threads, also known as the pitch  960 , can be increased to create a weaker coupling between adjacent needle segments. 
     Needles having engineered points of failure can advantageously further include an identification label. An example of such an identification label is label  814  in  FIG. 8 . Preferred labels are brightly colored, or include a fluorescent dye or other chemical compound that allows for convenient detection by an inspector using an optical scanner. 
     Knitting needles can be of any suitable sizes and dimensions. For example the needle containing segment can have various diameters to enable large stitches that can be made with large needles, or have small diameters to fine knitting. For example the length can range from 10 to 40 cm, and the diameter can range from 1.5 to 25 mm. Needles can be interchangeable and knitting needles as described herein to include crochet needles. 
     It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps can be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C . . . and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.

Technology Classification (CPC): 3