US3916559A

US3916559A - Vortex linkages

Info

Publication number: US3916559A
Application number: US496881A
Authority: US
Inventors: Frederick George Flowerday
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-08-23
Filing date: 1974-08-12
Publication date: 1975-11-04
Anticipated expiration: 1992-11-04

Abstract

There is disclosed a manipulative toy in the form of a linkage containing an even number of at least six links, each of which links comprises a central limb with two end limbs projecting one from each end thereof in planes mutually perpendicular to one another, each end limb of each link being journalled alongside an end limb of an adjacent link so as to pivot generally coaxially therewith and enable the linkage to be successively turned inside out through a position in which it defines a planar polygon, in which position half the journalled pairs of limbs stand perpendicular to the plane of the polygon at each vertex thereof whilst the remaining journalled pairs of limbs lie in the plane of the polygon and project from the mid points of the sides of the polygon towards the centre thereof.

Description

United States Patent Flowerday Nov. 4, 1975 VORTEX LINKAGES Primary Examiner-Hugh R. Chamblee 76 I t I F d k Geo Fl d 42 Assistant Examiner-Robert F. Cutting 1 nven or a t E i g ggrg 3 OH] Attorney, Agent, or FirmEdward F. Connors England [22] Filed: Aug. 12, 1974 [57] ABSTRACT PP 496,881 There is disclosed a manipulative toy in the form of a linkage containing an even number of at least six links, each of which links comprises a central limb with two [30] Fgrelgn Apphfahonrnonty t end limbs projecting one from each end thereof in Aug. 3, 1973 United Kmgdom 39910/73 planes mutually perpendicular to one another, each end limb of each link being journalled alongside an 5% 8 46/1 iz f gg gg end limb of an adjacent link so as to pivot generally d 27 28 coaxially therewith and enable the linkage to be suc- 1 1e 0 arc 3 cessively turned inside out through a position in which it defines a planar polygon, in which position half the journalled pairs of limbs stand perpendicular to the [56] References cued plane of the polygon at each vertex thereof whilst the UNITED STATES PATENTS remaining journalled pairs of limbs lie in the plane of 1,853,436 4/1932 Krause 273/155 the polygon and project from the mid points of the 2,959,888 1 1/ 1960 Noble i 46/28 sides of the polygon towards the centre thereof. 3,546,049 12/1970 Kostich 46/28 10 Claims, 6 Drawing Figures re 2 t Sheet 2 of 3 3,916,559

US. Patent Nov. 4, 1975 US. Patent Nov. 4, 1975 Sheet 3 of3 3,916,559

VORTEX LINKAGES FIELD OF THE INVENTION The invention relates to manipulative toys.

SUMMARY OF THE INVENTION The invention provides a manipulative toy in the form of a closed linkage containing an even number of at least six links, each of which links comprises a central limb with, at each end thereof, two end limbs projecting from the central limb in planes mutually perpendicular to one another, each end limb of each link being journalled alongside an end limb of an adjacent link so as to pivot generally coaxially therewith and en able the linkage to be successively turned inside out through a position in which it defines a planar polygon, in which position half the journalled pairs of limbs stand perpendicular to the plane of the polygon at each vertex thereof whilst the remaining journalled pairs of limbs lie in the plane of the polygon and project from the mid points of the sides of the polygon towards the centre thereof.

The end limbs may be journalled in surrounding tubes.

Said tubes may be constituted by helically coiled wire.

The tubes may be attached to or form part of either of the end limbs of each journalled pair.

Alternatively the end limbs may be press fitted into the tubes and the linkage held together by friction between the press fitted parts.

The links may be comprised of wire rods.

Alternatively the links may be comprised of rods of a plastics material.

The pivoted pairs of limbs may be permanently journalled together.

For example, they may be so journalled by a flexible connecting membrane.

When the limbs are permanently journalled together, the linkage may be moulded or fabricated in one piece from a material of sufficient inherent flexibility to permit each journalled pair of end limbs to comprise a single resiliently flexible member.

BRIEF DESCRIPTION OF THE DRAWINGS Examples of the invention will now be described with reference to the accompanying drawings, in which:

FIGS. II and 2 show a plan view of a continuous ring of members in alternative closed and open positions respectively;

FIG. 3 shows a single skewed quadrilateral for the continuous ring of members shown in FIGS. 1 and 2;

FIG. 4 shows an alternative single skewed quadrilateral formed from a continuous wire coil with straight extensions bent to fit into the coil of an adjacent similar member;

FIG. 5 shows a perspective view of a continuous ring of members conforming to a square; and

FIG. 6 shows a perspective view of a continuous ring of members in the form of a mobius strip.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIGS. 1, 2 and 3 a continuous ring of members in which the inner sides form a triangle is shown as an example.

Common edges

1, 2, 3, 4, 5 and 6 are constructed from tubes. In the plan view shown in FIG. 1, the longitudinal axes of the

tubes

1, 2 and 3 are lying in the plane of the paper and the longitudinal axes of the tubes 4, 5 and 6 extend outwards towards the reader at right angles to and from the plane of the paper. In alternative embodiments the longitudinal axis of one of the tubes 4, 5, or 6 may extend in the opposite direction, i.e. into the paper from the plane of the paper.

Inner edges

7, 8, 9, 10, l1 and 12 form a triangle from the upstanding tubes or common edges 4, 5 and 6. The inner edges extend at right angles from one end of the

tubes

1, 2 and 3 to the end of the tubes 4, 5 and 6 lying in the plane of the paper. The outer edges l3, 14, 15, I6, 17 and 18 extend from opposing ends of the

tubes

1, 2, 3, 4, 5 and 6 to which the inner edges are inserted. The

inner edges

7, 8, 9, l0, l1 and 12 are constructed from wire oflength 3 plus the lengths of extensions at right angles for insertion into the pivotal tubes, the same length as the tubes although this is not essential. The

outer sides

13, 14, 15, 16, 17 and 18 are constructed from wire of length 5 plus lengths for insertion into tubes. The tubes allow pivotal movement and the whole continuous ring of members can be rotated by hand.

The inside tube diameter should allow a close fit for the wires making up the inner and outer sides as shown in FIG. 1. In the case of FIG. 1 the inside tube diameter should be about 2 l)d (where d is the wire diameter) to allow a close but easy fit of four wires in a tube. Each inner and outer edge formed by a wire, at a distance of one unit tube length from each end, is bent in perpendicular planes. The short wires, the inner sides, are bent to an angle of ninety degrees, three to the left and three to the right. The long wires, the outer sides, are similarly bent to an angle of, substantially sixtythree degrees, three to the right and three to the left.

To this basic linkage may also be added the other two sets of wire quadrilateral edges, namely: the 6 which approximate the lines from the centre of the triangle to its vertices, and the 6 which approximate the lines from the top of the vertical tubes forming the common edges to the mid points of the triangle sides. This is shown by the peeked and dashed linesin FIG. 2.

To make a ring of continuous members as shown in FIG. 1, the wires forming the inner and outer edges 7 to 18 are taken in pairs, one long and one short of the same parity and are arranged into six quadrilateral forms, three with rightand three with left-handed twist. These skew quadrilaterals are placed alternately left-right-left-right-left-right in a ring and are joined by tubes 1 to 6 slipped over the ends of the wires. This can be done so that one end of each tube receives two long wires of opposite parity and that the other end of each tube receives two short wires of opposite parity. If this is done it will be seen that the linkage maintains its assembly yet is free to be turned successively inside out.

For a wire to disengage from a tube it must rotate on the axis of an adjacent hinge but is restrained from doing so by the fixed position of the first tube. A spring coil of wire might be used instead of tubing. The coil can be closely set in internal diameter to make a smoothly working hinge that does not tend to come apart.

In an alternative embodiment shown in FIG. 4, the ring of members may be constructed from a number of torsion springs 40 as one common edge with

straight end pieces

41 and 42 to form the inner and outer edges extending at fixed angles from the coil axis. The ends 43 and 44 of the inner and outer sides, are bent to fit into the torsion spring 40 of the next member thus providing a pivotal link.

It will be noted that a continuous ring of members is related to a regular plane polygon as shown in FIG. 1. It will be seen that one set of adjacent edges of unit length stand perpendicular to the plane at each vertex of the polygon. The other set of common adjacent edges lie in the plane of the polygon and approximate the lines from the centre of the figure to the mid points at the sides of it. One group of straight wire extensions lie in the polygonal plane and are equal to one half of a polygon side and make angles of ninety degrees with the common edge from which they extend, and an angle of ninety degrees with the common edge into which their extremities are engaged. With the common edge as unit length, the length of these extensions is equivalent to (tan A+2) where A 360/2N and where (+2) accounts for the hinge. (In the example previously described where the members resemble torsion springs, (+1) accounts for insertion in a hinge).

Another group of edges, i.e. those extending from the opposite ends of the adjacent members approximate the hypotenuse from the centre of the polygon to the top of a vertical common edge. It will be apparent that with the vertical edges as one unit, the length of these extensions is equivalent to tan A+2 +2) and that these extensions leave and engage the hinges at an angle B where TanB equals secA. At unit distance from their ends, these outer edges are bent at the appropriate angle to accommodate the common edge of the adjacent member, which accounts for the (+2). Two other sets of wire forms may be added to those mentioned. Those which approximate the lines from the top of vertical common edges to the mid points of the sides of the polygon; and those which approximate the lines from the centre of the polygon to its vertices. These four sets of wire forms may be used in different combinations throughout the linkage.

The continuous rings of members discussed so far as examples, have been based on the equilateral triangle as shown in FIGS. 1 and 2. They can however be made to any triangle provided that the common sides standing at the vertices of one closed triangular position are correctly proportional in length to allow the passage of the top vertex points through both closed triangular positions. In the case of the equilateral triangle and other regular polygons all common edges are equal.

A continuous ring of members can be based on other plane polygons, and, as in the case of the triangle, these can be regular or irregular.

FIG. 5 shows a square based continuous ring of members with two opposite common sides 51, 52 reversed in respect to the remaining two

sides

53 and 54. This variation may be used with a continuous ring of members of certain other geometries and periodicities.

A continuous ring of members is related to a plane polygon as previously described. It may be based on a polygon of any number of sides, but the larger number of sides the great flexibility of the continuous ring of members.

FIG. 6 shows a further example which can be seen to correspond to a mobius strip and is derived from the quadrilateral form shown in FIG. 2.

In addition to skewed quadrilaterals which have a generally rectilinear nature, by interconnecting each end of each common edge to each end of an adjacent common edge it can be seen that there is a framework of a generally solid shape formed. Thus, a solid continuous ring of members can be formed by producing in one piece a moulding using a material which would be sufficiently flexible to act as a hinge in thin section corresponding to the common edges of adjacent skewed quadrilaterals.

All the continuous rings of members as described previously can be made from wire or other material. For example the inner and outer edges may be wire pieces inserted into metal or plastic tubes. However the tubes can be formed as previously described, by a coil spring, or by any other device which functions as a pivotal restraint.

I claim 1. A manipulative toy in the form of a closed linkage containing an even number of at least six links, each of which links comprises a central limb with two end limbs projecting one from each end thereof in planes mutually perpendicular to one another, means pivotally joining said links such that each end limb of each said link is journalled alongside an end limb of an adjacent one of said links so that mutually adjacent links pivot generally coaxially with respect to one another and enable the linkage to be successively turned inside out through a position in which it defines a planar polygon, in which position half the journalled pairs of limbs stand perpendicular to the plane of the polygon at each vertex thereof whilst the remaining journalled pairs of limbs lie in the plane of the polygon and project from the mid points of the sides of the polygon towards the centre thereof.

2. A manipulative toy according to claim 1 in which the end limbs are journalled in surrounding tubes.

3. A manipulative toy according to claim 2 in which the tubes comprise helically coiled wire.

4. A manipulative toy according to claim 2 in which the tubes form part of an end limb.

5. A manipulative toy according to claim 2 in which the end limbs are press fitted into the tubes and the linkage is held together by friction between the press fitted parts.

6. A manipulative toy according to claim 1 in which the linkage is comprised of wire rods.

7. A manipulative toy according to claim 1 in which the links comprise rods of a plastics material.

8. A manipulative toy according to claim 1 in which the pivoted pairs of limbs are permanently journalled together.

9. A manipulative toy according to claim 8 in which the pivoted pairs of limbs are journalled together by a flexible connecting membrane.

10. A manipulative toy according to claim 8 in which the linkage is fabricated in one piece from a material of sufficient inherent flexibility to permit each journalled pair of end limbs to comprise a single resiliently flexible member.

Claims

1. A maNipulative toy in the form of a closed linkage containing an even number of at least six links, each of which links comprises a central limb with two end limbs projecting one from each end thereof in planes mutually perpendicular to one another, means pivotally joining said links such that each end limb of each said link is journalled alongside an end limb of an adjacent one of said links so that mutually adjacent links pivot generally coaxially with respect to one another and enable the linkage to be successively turned inside out through a position in which it defines a planar polygon, in which position half the journalled pairs of limbs stand perpendicular to the plane of the polygon at each vertex thereof whilst the remaining journalled pairs of limbs lie in the plane of the polygon and project from the mid points of the sides of the polygon towards the centre thereof.