Patent Publication Number: US-4548590-A

Title: Construction element

Description:
The invention relates to a construction element of the type which can be used, for example, with further construction elements to build models, shapes or patterns. 
     Many types of constructional elements have been proposed over the years. For example U.S. Pat. No. 3,550,311 describes elongate construction elements having interengageable jaws, which enable the elements to be joined end to end coaxially. However the jaws lie in the same plane when joined together and rely solely on friction to prevent the jaws sliding sideways relative to each other and becoming detected. Moreover the jaws are of complex form and tend to project considerably beyond the cylindrical surface of a rod on which they are snap fitted. U.S. Pat. No. 2,959,888 describes interlockable toy elements which also have jaws which snap together. The jaws of the elements in this case lie in mutually transverse planes and, therefore, are mechanically resistant to separation by relative sideways movement. However the frictional fit of the jaws will permit relative pivoting of the elements in the transverse planes. This can be a disadvantage when making, say, supporting legs of a model where a considerable amount of rigidity is required. 
     An object of the present invention is to provide a construction element having a jaw which can be located in a similar jaw of a further construction element in a manner which will provide a substantially rigid interconnection mechanically resistant to separation by sideways applied forces. 
     According to the invention there is provided a construction element comprising a body having resiliently openable jaws thereon locatable between similar jaws of a further construction element with the jaws of the respective elements arranged in mutually transverse planes, and a jaw retention surface on the body, said jaws defining an open front end between free ends thereof whereby said jaws locate each other with the free ends of the jaws of each element cooperating with said retention surface on the other element to inhibit relative movement between the elements. 
     The arrangement of the located jaws in mutually transverse planes provides the required mechanical resistance to sideways applied separation forces and the jaw retention means on the body provides the desired rigid interconnection of the two elements which gives, e.g. useful resistance to relative angular deflection of interconnected elements. 
     Preferably the jaws have a closed rear end so that when the jaws are located in the similar jaws the free ends of the jaws of each element are positioned behind the closed rear end of the other jaws for engagement with the retention surface. This arrangement results in a particularly rigid joint between elements. In such a case the retention surface may be defined by a rear surface of means defining the said closed rear end of the jaws. 
     The retention surface may comprise a groove in the body behind a closed rear end of the jaws so that when the jaws are located between the similar jaws the free ends of the jaws of each element locate in the groove behind the closed rear end of the other jaws. The aforesaid rear surface of the means defining the closed rear end of the jaws may form a wall of said groove. The use of the groove provides a very positive location for the free ends of the jaws when the two sets of jaws are brought together. 
     Preferably the free ends of the jaws of each element engage the retention surface of the other element in a snap-fit manner. The snap-fit provides optimum resistance to direct separation of the sets of jaws as well as increased resistance to separation by relative angular movement of the interconnected elements. 
     The body is preferably elongated and may have the jaws at an end thereof. The jaws are preferably dimensioned so as to snap-fit on to the body of a similar construction element. The elongate body could, of course, have jaws at each end which would preferably lie in a common plane. 
     The elongate body may have jaws at one end and a jaw locating member at its other end extending transversely of the body. Preferably the jaw locating member is arranged so that when the jaws of said similar construction element are located on the member they lie in a plane transverse to the plane containing the jaws at said one end of the body. The jaw locating member may comprise a transverse bar mounted on a support such as finger means on the body. The finger means may comprise two spaced fingers on the body interconnected at or adjacent free ends by the bar. Means may be provided for inhibiting rotational movement of jaws located on the jaw locating member. Such means may comprise a projection, e.g. a rib or flange, on said member which lies between said free ends of the jaws when the jaws are located on the member. 
    
    
     A construction element in accordance with the invention will now be described by way of example with reference to the accompanying drawings in which: 
     FIG. 1 is an elevation of one form of construction element in accordance with the invention having jaws at each end, 
     FIG. 2 is a plan view of the element shown in FIG. 1, 
     FIG. 3 is an end view of the element of FIG. 1, 
     FIG. 4 is a cross-section of the element of FIG. 1 on the line IV--IV in FIG. 1, 
     FIG. 5 shows the way in which jaws of the element grip the body of another element, 
     FIG. 6 shows the way in which two sets of jaws are located one within the other, 
     FIG. 7 shows an alternative form of element having a jaw locating member at one end and jaws at the other end, 
     FIG. 8 is a cross section through the jaw locating member in FIG. 7 on the line VIII--VIII in FIG. 7, 
     FIG. 9 is a cross section through an alternative form of jaw locating member, and 
     FIGS. 10 and 11 are elevation and plan views respectively of an element having another form of jaw locating member. 
    
    
     Referring to FIGS. 1 to 4 a construction element 10 is moulded from resilient plastics and comprises an elongate body 1 of circular cross section. Two jaws 2 are formed at each end of the body and have free ends 3. Each pair of jaws 2 has an open front end 4 defined between the free ends 3 and a closed rear end 5 defined by an end section 6. Circumferential grooves 7 are formed in the body 1 immediately behind the end sections 6, a wall of each groove forming a rear surface 8 of the adjacent end section. 
     As shown in FIG. 5, the jaws 2 can be located on the body 1 of another element 9, the distance X (FIG. 3) between the free ends 3 being less than the diameter D (FIG. 4) of the body. Such location is effected by first placing the body 1 of the other element 9 against the free ends 3 of the jaws 2. A force in direction F is then applied to the element 9 thereby causing the resilient jaws to open and receive the body 1. In view of the resilient of the plastics material, the jaws 2 snap-fit on to the body 1 whereby the flat internal surfaces of the jaws 2 and end section 6 grip the body 1 at points around its periphery whilst permitting relative rotation between the two elements 9, 10 about the axis of element 9. 
     FIG. 6 shows the way in which jaws of the construction element 9 can be located between the jaws of construction element 10. To locate the jaws, the elements are first rotated about their longitudinal axes until the jaws lie in mutually perpendicular planes. In FIG. 6, the jaws 2 of element 9 lie in a vertical plane and the jaws 2 of element 10 lie in a horizontal plane. The open ends 4 of the jaws are then moved towards each other until the free ends 3 interengage. The distance X is less than the width of the jaws and so axial loading is necessary to cause the free ends 3 to ride over each other to permit initial intercalating of the jaws. Further axial loading is then applied to cause the free ends of the jaws of each element to ride over the end section 6 associated with the jaws of the other element and to snap into the grooves 7. Each of the free ends 3 thereby resiliently engages part of the adjacent surface 8 of the relevant end section 6 and an opposite edge 12 of the relevant groove 7. As the jaws 2 of one element overlap the jaws 2 of the other element in a snap-fit manner, the joint achieved by the intercalating jaws provides high resistance to separation by sideways applied forces S in vertical, horizontal or intermediate planes. Also, the joint is capable of transmitting rotational forces R from one element to the other and is resistant to tensile separation or separation by relative angular displacement of the elements in any plane. 
     Where it is not essential that the jaws grip the body 1 as in FIG. 5, the body 1 may be of reduced diameter to avoid the need for a groove 7. The jaws would then be retained simply by the surfaces 8. 
     Where the elements are connected as shown in FIG. 6, the jaws at the opposite end of element 9 will be in a plane perpendicular to the plane containing the jaws at the opposite end of element 10. This may be inconvenient in some instances and FIG. 7 illustrates a way of overcoming that. In FIG. 7 one end of body 1 carries jaws 2 whilst the opposite end has two parallel fingers 12a interconnected by a cylindrical bar 13 having a diameter equal to D. Jaws of a further element can be snapped on to the bar 13. The axis of the bar 13 lies a plane perpendicular to the plane containing the jaws 2 at the other end of the element therewith. Therefore if the body 1 is used, say, in place of element 10 in FIG. 6, jaws of a further element which locate on bar 13 will lie in the same plane as the jaws of element 11. If it is desired to prevent or limit rotation of jaws around the bar 13, the bar can be formed with a rib or flange 14 as shown in FIG. 8. The flange lies between the free ends 3 of the jaws 2. 
     FIG. 9 shows an alternative means of preventing or limiting rotation about bar 13 by using a tapering web 14&#39; which extends between the bar 13 and the adjacent end of the body. 
     In the embodiment of FIGS. 7, 8 and 9 the distance E between the fingers is slightly greater than W. 
     In FIGS. 10 and 11 the body 1 has its end opposite the jaws 2 formed with a transverse bar 20, a groove 7 being formed in the body adjacent the bar. Jaws 2 of a further element can be located in position a, b or c as indicated in broken lines in FIG. 10. In positions a and c the jaws 2 can rotate about the bar 20 but in position b the jaws engage the groove 7 and such rotation is therefore prevented. 
     A rotary interconnection between the jaws 2 and the bar 13, 20 enable a knuckle type joint to be formed between two elements. In certain cases it may be desirable to provide an element which comprises a body having jaw engaging bars such as 13, 12 at both ends. 
     Whilst specific reference has been made to a body which is of elongate form the body could be of a non elongate form. 
     Construction elements in accordance with the invention can be used to form an infinite variety of patterns, geometric designs, models etc. and may be supplied in a pack containing elements in various colours and other constructional components such as wheels or rings. 
     Whilst specific embodiments of the invention have been shown and described in detail it will be understood that the embodiments may be modified or varied without departing from the spirit or scope of the invention.