Abstract:
A construction toy comprises a multiplicity of straws, wherein at least some of the straws are joined together with a first straw extending through a second straw via a pair of transversely aligned holes in the second straw. Further, at least some straws are joined together longitudinally by an end of one straw extending tightly into an enlarged socket end of another straw. The invention includes a punch for punching the transverse holes in a straw, a cutter for cutting the straws to a desired length, and an expander for forming the enlarged socket in an end of a straw.

Description:
The present invention relates to a constructional toy or model comprising a multiplicity of straws joined together, to a method of making the toy or model and to a constructional system or kit for making models out of straws. It further provides a device for punching transverse holes in a straw. 
     A construction system for making models out of straws has previously been sold under the trade name Construct-O-Straws. It comprised a set of plastics straws and plastics joining parts formed with spigots which fitted endwise into the straws to form junctions between them. The joining parts might have two spigots for forming a linear or comer junction, three spigots for forming a T-junction or four or more spigots for forming more complex junctions. However, the comer parts were noticeable and restricted the appearance of the models made and the range of models that could be made. Furthermore, if a user ran out of joining parts, or of parts of a particular kind, he then had to stop or to purchase an additional kit. 
     Another construction system is disclosed in U.S. Pat. No. 3,469,339. Tubular members are provided with pre-cut holes each hole having its axis perpendicular to the hole at either side to enable the construction of various models. 
     A construction element is disclosed in U.S. Pat. No. 4,274,222 and comprises a flexible tube each end of which can receive a rod-like member by pushfit. The flexible tube has a pair of pre-cut oppositely facing holes at its mid-point which can accommodate another flexible tube. Using the several such elements a user is able to construct a variety of joints to construct models from the rod-like members. 
     One problem with which ,the invention is concerned is to provide a constructional toy, based on assembling straws together, in which the user is not liable to run out of necessary parts for model making. 
     Another problem with which the invention is concerned is to provide constructional toys or models based on straws in which the whole of a complex model may, if the user so wishes, be formed from the straws. 
     A further problem with which the invention is concerned is to provide simple and effective apparatus for use in making toys or models as aforesaid. 
     In one aspect the invention provides a construction kit comprising a multiplicity of straws; characterized by 
     a punch for punching pairs of transversely aligned holes at arbitrary locations through the straws; 
     the straws and punch permitting a model to be made in which at least some straws are joined together with a first straw extending through a second straw via a pair of transversely aligned holes at an arbitrary location along the second straw, each of said holes being surrounded by portions of the second straw and the first straw fitting tightly within the holes in the second straw. 
     In a further aspect the invention provides a method for making a model by joining straws together, including the steps of: 
     providing first and second straws; 
     punching the a first straw at an arbitrary position along the straw with a punch having substantially the same external diameter as the straw so that the first straw becomes flattened and a pair of transversely aligned holes are formed which are separated by undamaged regions of the straw; 
     allowing the straw to recover its shape; and 
     passing a second straw through the pair-of holes in the first straw to form a joint in which there is frictional resistance to axial and angular relative movement between the first and second straws. 
     In a further aspect the invention provides a constructional system for making models out of straws, including a punch for punching pairs of transversely aligned holes through the straws, a cutter for cutting the straws to length and an expander for expanding ends of straws into receiving sockets. 
     The invention also provides a set of tools for making models out of straws, including a punch for punching pairs of transversely aligned holes through the straws, a cutter for cutting the straws to length and an expander for expanding ends of straws into receiving sockets. 
     Other preferred aspects of the invention are defined in the accompanying claims to which attention is hereby directed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     How the invention may be put into effect will now be described with reference to the accompanying drawings in which: 
     FIG. 1 is a diagrammatic perspective view of a punch unit for forming pairs of transverse holes in a straw; 
     FIG. 2 a  and FIG. 2 b  are diagrammatic end views of the punch of FIG. 1 showing successive stages in the cutting of transverse holes in a straw; 
     FIG. 3 a  and FIG. 3 b  are respectively a side and plan view of a straw in which holes have been cut using the punch unit of FIG. 1; 
     FIG. 4 is a perspective view of a length and angle guide for use with a punch as shown in FIG.  1  and with a movable shuttle for longitudinal and angular positioning of a straw in which holes are to be cut, 
     FIG. 5 is a perspective view of a punch tool which can be hand held or used with the length and angle guide of FIG. 4, 
     FIG. 6 is a transverse section of the shuttle and of the length and angle guide and 
     FIG. 7 is a view of the punch, part of the length and angle guide and part of the shuttle during punching of the first hole in a straw; 
     FIG. 8 is a view of punched straws and other toy or model components being assembled together; 
     FIG. 9 is a perspective view of a cutting tool and part of an associated length guide, and 
     FIG. 10 is a view of the cutting tool separated from the length guide and in use for hand cutting of straws; 
     FIG. 11 is a side perspective view of a straw end stretching tool about to be inserted into an end of a straw, 
     FIG. 12 is a front perspective view of the stretching tool partly inserted into an end of the straw and 
     FIG. 13 is a front view of jaws of the stretching tool after they have been forced apart to stretch the straw; 
     FIG. 14 is a front perspective view of a multi-function straw cutting, punching and expanding machine, 
     FIG. 15 is a rear view of the machine and 
     FIG. 16 is a detail view in the vicinity of the shuttle of the machine; 
     FIGS.  17 ( 1 )- 17 ( 6 ) are instructions for making a model swing from “bendy-straws” which can be made simply by punching the straws, cutting them to length and fastening them together using an assembly tool; and 
     FIGS.  18 ( 1 )- 18 ( 10 ) are instructions for making a model car from “bendy straws” involving the expansion of the ends of some of the components and the joining of them end-to-end. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The straws which are useful for making the present construction toys are plastics straws, preferably “bendy straws” (i.e. straws which incorporate a corrugated bendable region) and preferably made of polypropylene. Suitable straws of 5 mm external diameter are available from Unique Industries Inc of Philadelphia, USA and from Amscan Inc, also of the USA. For a limited range of models in which strength is less important and end to end tube joins are not needed, paper straws could be used instead. 
     FIG. 1 shows a polypropylene straw  10  of 5 mm external diameter supported between the walls of entry guide  12 , which have a similar spacing to the external diameter of the tube  10 , and passing towards a punch  14  and a die  16 . A flat support region or throat  18  surrounds the die  16  and is 7.8 mm wide which is sufficient to allow a region of the tube adjacent the die  18  to become flattened during the punching operation. As handle  20  is depressed the punch  14  which is of 5 mm external diameter contacts the straw as shown in FIG. 2 a  and then travels down and crushes the straw flat up to the full width of the throat, after which the punch  14  bursts through the straw  10  and ejects two 5 mm diameter discs  19  into the barrel of the die as shown in FIG. 2 b.  The handle  20  is released and spring-returns, permitting the straw to recover its circular shape. As seen in FIGS. 3 a  and  3   b,  there is formed a pair of transversely opposed holes  22  in the straw  10  which are separated by un-cut regions of the straw and are closed. The holes  22  assume an elliptical shape in side view and provide the necessary frictional grip on a straw passed through them so that there is formed a joint which may be “posed” in the sense that the axial and angular positions of the joined components can be retained. We have found that the size of the hole punched through the straw is important to forming the desired poseable joint with another straw of the same size, and that the best size for the hole cut is equal to the external diameter of the straw. With the present size of straw, the range of tolerance is about ±0.1 mm. If the hole size is too small, then it is difficult to push another straw through, and if it is too large, the friction grip of the resulting joint is too low for model making. 
     FIGS. 4-6 show in more detail a practical arrangement for the punch. The punch  14 , die  16  and operating handle  20  are formed as a separate unit  25  which is a removable fit onto a length and angle guide  27 . At one end of the guide  27  there is formed an entry guide region  12   a  which leads to a recess  28  within which the punch unit  25  is removably retainable e.g. by a ball catch  30  which snaps into a recess (not shown) in the unit  25 . At the outlet side of the recess  28  an elongate bed  31  is formed a T-shaped slideway  32  along which is formed a distance scale or rule  34 . A shuttle  36  fits into and is movable along the slideway  32 , its longitudinal position being indicated by a pointer  38 . Within the shuttle  36  is a barrel  39  which is supported for bi-directional rotation as indicated by arrows  40  and which carries a post or handle  42 . A straw  10  with a first pair of the transverse holes  22  punched in it may be pushed onto the post  42  which fits into the holes. In this way the longitudinal and angular position of the straw may be defined and may be maintained during the punching of one or more further pairs of holes through the straw. The slideway  32  is formed with recesses at regularly spaced intervals along its length and the outer surface of the barrel  39  is also formed with recesses  43  which are engageable by a double duty ball indent  40  for indexing length and angle. In the embodiment shown, angle is in 45 degree steps, but other intervals are possible. After the post has engaged into the holes  22 , it may be rotated through two indexed steps, for example, to bring it to the position shown in phantom and to permit a second pair of holes at a different position along the straw to be punched at right angles to the first pair of holes. 
     The cutting of the first end hole using a second form of the shuttle assembly is shown in FIG. 7, the form of the shuttle being generally as shown in FIG.  16 . The shuttle  36   a  is moved along the slideway  32   a  so as to bring the pointer  38   a  into register with a minimum distance mark  45 . The end of the shuttle  36   a  nearer the punch has on its rotatable barrel part  39   a  a rearwardly facing lug  46  which is located at its top in the position shown. A downwardly facing through-hole is formed in the lug  46 , into which is insertable a pin  50  whose diameter equals the external diameter of a straw. In order to form a first pair of holes, the straw  10  is engaged into the entry guide  12   a  and advanced until it contacts the pin  50 . The handle  20  is then depressed to punch the first hole pair. The pin  50  is then removed, the first pair of holes  22   a  is brought into register with the hole in the flange  46 , and the pin is returned and engaged into the holes  22   a.  The pin  50  then provides location for the straw  10 , so that the distance to the next desired hole can be measured by sliding the shuttle along the distance scale or length guide  34   a  and reading off the required distance. Holes at the same angular positions or at other angular positions (e.g. 45 or 90 degrees apart) can be created by rotation of the barrel  39   a.  In order to facilitate obtaining of accurate results by a child user, the ball indent provides longitudinal and angular indexing as previously discussed. 
     Methods of assembling straws together are shown in FIG. 8. A rod-like solid plastics assembly tool  60  is slid into a pre-punched straw  62 , after which a second pre-punched straw  64  may be pushed onto the first straw  62  to establish the joint, and the assembly tool  60  can be withdrawn. The assembly tool  60  provided the necessary rigidity to the straw  62  during assembly, speeds up assembly of the joint and makes assembly easier for people of limited dexterity. Also shownin FIG. 8 is an accessory, in this case a wheel  66  which is free to rotate on a pin  68  which is a push fit into an open end of a straw  70 . The pin  68  can be used for mounting other accessories e.g. aeroplane propellers. 
     A requirement in model-making is to cut the straws to length. For this purpose a guillotine-type cutter may be provided  80  (FIGS. 9 and 10) may be provided and may be used alone or in position with a length measuring device  82  which fits onto the cutter when required. 
     The range of models which can be made is expanded if a facility is provided for joining the straws end-to-end, and this is advantageously by socketed joints e.g. the joint  72  of FIG.  8 . To form a socket, an expander device  80 ′ is provided which has a pair of jaws  82  of semi-circular profile pivoted together at  84  and controlled by handles  86  biased apart by a spring  88 . The jaws  82  are inserted into the open end of a straw  89 , after which the handles  86  are moved together by gentle and gradual finger pressure to move the jaws to the position of FIG. 13 where their largest dimension when viewed in front profile is 5.8 mm. Polypropylene exhibits a thixotropic-type behaviour in the sense that an abrupt movement apart of the jaws is likely to burst the socket as it is formed, whereas a more gradual movement will permnit the polypropylene to deform and assume a new shape. 
     For some modelling kits it may be desirable to provide a tool  90  which combines the functions of a punch, cutter and stretching device. For this purpose, a base  91  is provided which has three parallel inlet guides. A first inlet guide  92  leads to the hole punch, a second inlet guide  94  leads to the cutter and a third inlet guide  96  leads to an expander device. The three guides  92 ,  94  and  96  are of concave semi-circular shape and are directed parallel to one another. In alignment with the guide  92  there is formed a slideway  98  for a shuttle  38   a  and associated distance scale  34   a.  A support channel  100  extends along the base parallel to the slideway  98  for supporting cut portions of straw. The length measuring facility of the shuttle  38   a  is common to the punching and cutting operations and for this purpose the shuttle  38   a  has a lateral extension or ‘wing’ which extends across the channel  100  and provides an abutment for positioning a straw in the channels  94 ,  100  prior to cutting. In association with the base unit there is provided a combined punch, cutter and expander unit which demountably clips onto the base and has a common actuating handle for a punch  103 , guillotine cutter  105  and expander  107  whose functions have already been described. 
     The complexity of the models which can be made depends on the facilities employed, and FIGS.  17 ( 1 )- 17 ( 6 ) and  18 ( 1 )- 18 ( 10 ) show the range of possibilities. These drawings are intended to be supplied with straws and the tools previously described as modelling kits, and to be understandable by children. They therefore do not need detailed description here. It will be apparent that models of considerable complexity can be produced simply by cutting straws to length and punching pairs of holes in them. In FIGS.  17 ( 1 )- 17 ( 6 ) a model swing uses these facilities and also takes advantage of the bendable corrugated regions of two of the straws to shape the seat. In FIGS.  18 ( 1 )- 18 ( 10 ) some of the straws are joined end to end by socket joints, and accessories (in this case wheels) are attached to the model using pins of the type previously described. 
     It will be appreciated that the embodiments described above are nonlimiting, and that modifications may be made to them without departing from the invention.