US 3451074 A
Description (OCR text may contain errors)
June 24, 1969 s CRANE ET AL VENTILATING SPACER Filed Feb. 15. 1965 FlG.5
INVENTORS SAMUEL P. CRANE STEPHEN D. KENT ATTORNEY United States Patent 3,451,074 VENTILATING SPACER Samuel P. Crane, 23 Pine Drive, Great Neck, N.Y.
11021, and Stephen D. Kent, 567 Liberty St., Newburgh, N.Y. 12550 Filed Feb. 15, 1965, Ser. No. 433,262 Int. Cl. A47c 23/00, 25/00 US. Cl. -347 1 Claim This invention relates to ventilating spacers and more particularly to the kind having a length of coiled wire wrapped around a peripheral frame to form two interesting sets of rows of coils.
Patent No. 2,801,681 discloses a ventilating cushion having a ventilating spacer or inner spring unit comprising a peripheral wire frame and a coiled wire wrapped continuously across the frame to form such entangled sets of rows. The interlocking action of the intersecting and entangled rows of coils tends to keep them in place against excessive relative movement or displacement but as indicated in the patent a border spring in addition can be used to further resist shifting along the frame of the half turn bends integrally joining the ends of adjacent rows. The border spring is also a continuous length of coiled wire into which the wire frame is inserted with it axis generally following the outline of the frame, and it is particularly useful with frames of polygonal or curved outline to maintain against displacement, the half turn bends.
It is now proposed to dispense with the need for a border spring by shaping the frame itself in such a manner as to resist shifting of the bend joining the ends of the rows of coils with or without retaining the relatively tight interlocking action of the rows of coils where they cross the rows of the intersecting set. This is accomplished by providing indents in the frame engaging the bent and portions of the rows at their juncture with the frame and slightly tensioning the coils as the rows are wrapped around the frame, whereby the bends are self-held against displacement by the tendency of the coils to contract and the resistance of the coils to expansion which the slightly stretched coils must undergo if the bends are to work out of the indents.
Embodiments of the invention are illustrated by way of example in the accompanying drawings, in which:
FIG. 1 is a top plan view of a ventilating cushion with its cover partly broken away to show underlying structure, and showing in hidden lines one form of the indented peripheral frame according to the invention;
FIG. 2 is a top plan view on an enlarged scale of a portion of a continuously corrugated form of the frame, and showing a portion of two intersecting rows of coils and the half turn bends;
FIG. 3 is an enlarged top plan view of a portion of yet another form of the indented frame, and showing in section a ferrule for connecting the adjoining ends of the frame;
FIG. 4 is a view similar to FIG. 3 but showing a portion of the frame of FIG. 2 and a suitable ferrule therefor;
FIG. 5 is an enlarged top plan view of a portion of the indented frame of FIG. 1; and
FIG. 6 is a top plan view of a modified form of the inner spacer unit of a ventilating cushion, the unit having a corrugated frame that is circular in outline and the rows of coils being so spaced as to concentrate the rows at the central area of the unit.
In FIG. 1 a ventilating cushion generally indicated by reference numeral 10 comprises an inner spacer unit having a peripheral frame 11 and intersecting row 12 of coiled wire wrapped around the frame, in the manner taught by Patent No. 2,801,681. As is clearly shown in FIG. 2, each row 12 of coiled wire terminates in a onehalf turn bent portion 13 which joins adjacent rows of 3,451,074 Patented June 24, 1969 coiled wire. The rows 12 of coiled wire are arranged preferably in two substantially mutually perpendicular sets. To prevent bunching or concentration of the rows at any particular area by withdrawal of the rows from the proper positions thereof to leave unduly empty areas in the unit, the rows of the two sets are more or less entangled with one another where they intersect. The resulting interlocking or movement limiting action tends to keep the rows of coils in place.
It is attained by the insertion of a coil of One row into the space in the adjacent coil of the intersecting row, and the coplanar arrangement of the axes of all the rows. Such substantially coplanar arrangement of the rows limits the relative possible displacing movement of the contacting or nearly contacting coils. The premissible amount of such relative movement depends, of course, on the diameters of the coils relatively to the pitch thereof which determine the desired density or flimsiness of the spacing unit with the same number of rows.
The frame 11 is preferably formed from a single continuous length of wire and has a plurality of spaced apart indents 14 therein for the reception of the bent portions 13 in the coiled wire to further resist shifting of the rows (see also FIG. 5). Bend-guiding portions 15 of the frame between adjacent indents are preferably slightly convex outwardly so that a bent portion 13 will tend, during the wrapping operation and thereafter, to seat itself and to be retained in an indent if there is a slight tension in the coiled wire, thereby not only facilitating the wrapping operation, but also making it possible to dispense with the usual border spring around the frame, it being understood that the length of any row of coils must be substantially increased by at least the depth of an indent if the half bend is to come out of the indent. Opposed indents in opposite sides of the frame receive the half turn bends at the respective ends of a row.
In FIG. 2, the frame 11 is formed from a continuous length of wire that is preferably corrugated throughout its entire length, and the bent portions 13 of two mutually perpendicular rows 12 of coils are shown in engagement with relatively closely spaced indent 14 of the frame. The interlocking action of the rows of coils is clearly shown and it will be observed that the diameter of the coils is preferably, though not necessarily, somewhat greater than the pitch of the coils so that when the rows are forced together or preassembled to make their axes coplanar, the relatively large coil of one row acts as a wedge to spread that coil of the other row into which said one row is forced, or vice versa. As has been indicated, some entanglement of the intersecting coils or substantial limitation of the relative movement thereof occurs even if the coils are spread out so that their pitch exceeds their diameter. The indents on the frame of this invention do in much the manner shown in US. Patent No. 2,781,085, tend to keep the end bends of the coils at the frame in place even if the coils are spread apart to increase the pitch substantially inside of the frame, and regradless of the ratio of the diameter of the coplanar coils to the pitch.
FIG. 3 shows the usual connecting ferrule 16 for the adjoining unindented or straight ends of the frame. The portion 15 of the frame 11 between the indents 14 may remain straight in this embodiment so that a simple cylindrical ferrule of circular cross-section is used. If the frame is closely corrugated as in FIGS. 2 and 4, the ferrule becomes elliptical in cross-section.
The invention is not limited to a frame of substantially quadrilateral shape but is applicable to those having any shaped outline. In FIG. 6 the invention is shown applied to a circular ventilating cushion. In that case, the frame 11 being circular in outline, i closely corrugated throughout its length and the rows of coils are wound around the frame in the manner mentioned above and in Patent No. 2,801,681. However, the rows of coils of each set are spaced preferably closely together where most needed, namely, at the central area of the unit, than at the marginal areas which are subject to lesser use. The rows also differ in length, the middle rows nearer the diameter of the unit being longer than the chord-like marginal rows.
While specific reference has been made herein to ventilating cushions taught by Patent Nos. 2,781,085 and 2,801,681, it is to be understood that this reference is to avoid detailed explanations of known devices. While certain specific forms of the invention have herein been shown and described, it is to be understood that various obvious changes may be made therein without departing from the spirit of the invention.
1. A spring structure comprising a sinuously convoluted peripheral frame consisting only of an elongated wire member in the general outline of a geometric figure having a plurality of inwardly extending troughs therein separated by a crest between each pair of adjacent troughs and means securing the ends of said member together to close the frame, and two mutually perpendicular and substantially coplanar sets of sections of a coiled wire spring wrapped backwards and forwards in zig-zag formation around and across the frame and tensioned, each set including one-half turn bent portions, each portion being common to and joining the ends of adjacent sections of the same set of sections, each of said one-half bent portions being looped over the member at the junction of the half turn portion with a trough of the member thereby to position the ends of adjacent sections joined by said portion relatively to the frame, the middle sections of each set of sections being closer together than the marginal sections of the set thereby to provide a greater density of coils at the central area of the spring structure than at the marginal area thereof.
References Cited UNITED STATES PATENTS 3,237,216 3/1966 Blechman 297453 X 2,801,681 8/1957 Crane 297453 2,781,085 2/1957 Crane 5-347 1,911,276 5/1933 Harley 5-189 X CASMIR A. NUNBERG, Primary Examiner.
ANDREW M. CALVERT, Assistant Examiner.
U.S. Cl. X.R. 297453