MXPA97009335A

MXPA97009335A - Colc spring nucleus

Info

Publication number: MXPA97009335A
Application number: MXPA/A/1997/009335A
Authority: MX
Inventors: j wells Thomas; R Ramsey Henry; J Provost Wayne
Original assignee: L&P Property Management Company
Priority date: 1995-06-01
Filing date: 1997-12-01
Publication date: 1998-02-01

Abstract

The present invention relates to a spring core for a mattress, which comprises a plurality of springs of helical turns configured identically and each composed of a piece of wire with a central spiral portion of a first radius defining a central turn and ending at the opposite ends with upper and lower end turns without knots, placed in planes substantially perpendicular to the mentioned spiral axes, the mentioned turns being placed in rows side by side, and being connected to each other, in the above mentioned upper and lower end turns, with helical connecting wires placed in the mentioned planes, the upper and lower end turns having a "U" shape, and having a relatively straight longer leg and a shorter leg arched, locating this shorter arched leg at the free end without knots of each of said turn s of end, and having a radius substantially less than the first mentioned radius of the central spiral portion of the circular spring, the legs of each end turn being laterally spaced outwardly from the central spring axis, the outwardly central spring axis, the radial spacing between the longer leg and the central spring axis being smaller than the corresponding spacing between the axis of the central spring and the shorter leg of the same end turn, turning the opposite end turns of each spring for approximately 180 ° some in relation to the others, to arrange the legs, the longest and the shortest, of the turn of the upper end of the coil spring, in a mirror symmetry with the legs longer and shorter , respectively, of the lower end spin associated

Description

MATTRESS SPRING NUCLEUS Field of the Invention This invention relates to a spring core for a mattress, and particularly, to a spring core composed of identically formed mattress cores placed in lines side by side, and each core of the mattress is composed of a single piece of wire and has a central spring portion and ends in end turns without upper and lower knots, with springs of adjacent helical turns which are joined at their end turns by a helical connecting wire.

BACKGROUND OF THE INVENTION Traditionally, mattress cores have consisted of a plury of parallel and spaced rows of helical coil springs, mounted between edge wires; the coil springs adjacent to the edge wires are attached thereto by helical connecting wires, metal foil fasteners, or other connections. The upper and lower end turns of the adjacent springs are generally connected to one another by helical connecting wires; the helical connecting wires are transverse or perpendicular to the columns of the coil springs. The coil springs of each row are arranged in a rectilinear relationship with one another, so as to form rows of springs spaced apart and parallel inside the edge wires. The upper end turns of the coil spring springs without knots, very often are made with straight portions or legs, which support each other when placed side by side. For example, in U.S. Patent No. 4,781,360, the end turns have deviations or displacements that straighten the curved portion to thereby allow the end turns adjacent to each other to be joined. Alternatively, the end turns of the spiral may be rectangular with two opposite straight legs, as in German Patent Number 3,321,991. The adjacent coil springs are connected to each other at their end turns, both the upper and lower ends, by helical connecting wires. A leg of a "U" turn of an end turn of a coil spring is placed next to the opposite leg of the U-shaped end turn of the adjacent coil spring. The legs next to each other are joined together with a helical connecting wire. However, when assembled, the coil springs of this spring core can be moved within the tie wire, thus causing an incorrect nment or an unparalleled nment of the coils in adjacent rows of turns. Incorrect nment causes the coil springs to misn. The lines connecting the center axes of the coil springs no longer form a 90 ° angle as they should. The incorrect nment by the same changes the rectangular or square spring core by a diamond. Such a rare form has to be corrected at an additional cost. In order to avoid this problem of improper nment, spring cores with individual coil springs were developed with U-shaped end turns with a longer leg than their opposite leg, as in the United States Patent. Number 4,817,924. Once again, the adjacent coil springs were connected with the helical connecting wire at their end turns. However, because of the difference between the length of the legs of each turn in a "U" shape, the bond wire is wrapped with one more turn around the longer leg of the end turn of the turn in shape of "U" and one less turn around the shortest leg immediately adjacent to the adjacent end turn. The different lengths of the legs joined with a helical connecting wire corrected the incorrect nment or the problem of the displaced turn. In the Patent of the United States of North America Number 4, 817,924, the longest leg of each "U" shaped end turn, is disclosed as more separate from the central portion of the coil spring or the spring axis, than the distance between the shortest leg and the portion central axis of the helical spring. The purpose of this separation is to eliminate interference and noise when a load is placed on the spring core causing compression of the coil springs. When the springs are produced in accordance with that disclosed in U.S. Patent No. 4,817,924, problems may arise during manufacture. For example, because both legs of the U-shaped end turns are very straight, the turns can be moved or biased in the assembly die machine before joining the coil springs. Improper movement or settling, as a result of the skewing of the coil springs within the dies, causes clogging and similar problems when the end turns of the turns are joined.

Therefore, the aim of this invention has been to eliminate any bias or incorrect alignment problem with the end turns of knotless turns inside the dies of the joining machine of a joint, and an assembly machine. Another object of the invention has been to allow the end turns, which are to be assembled, to be assembled together to be held in a more consistent manner, and to be placed side by side for the joint during the assembly of the turns Another object of the invention has been to provide a spring core in which the upper and lower "U" -shaped end turns of the turns of the adjacent springs are more tightly joined between or within the helical junction wires. Another object of the invention has been to provide a trouble-free manufacture and assembly of knotless loop turns by forming a small radius on the free end of each end turn of the knotless turns, thereby reducing the pressures inside the assembly machine and, finally, the cost of the resulting assembled product.

SUMMARY OF THE INVENTION The invention of this application, which meets the objectives, comprises a spring core for a mattress, composed of a plurality of helical coil springs with an identical configuration. Each coil spring is composed of a single piece of wire, and has a central portion with a first radius defining a central axis of the spring and terminating at the end turns without knots generally in the form of upper and lower "U" opposite, each placed in a plane substantially perpendicular to the axis of the spring. The springs are arranged in rows situated side by side, which are connected between them by the upper and lower part of the end turns by helical connecting wires. The helical connecting wires run perpendicularly or transversely to the columns or rows of springs, and are positioned in the planes of the upper and lower end turns. Each upper and lower end turn has substantially a "U" shape, and has a relatively long straight leg and a shorter arched leg that are connected to each other by a base network. The shorter arcuate leg is located at the free end without knots of each end turn, and has a radius substantially less than the first radius of the central portion of the coil spring. Both legs, the long and the short, of each end turn are laterally spaced outwardly from the central portion of the coil spring. The separation between the longest leg of each U-shaped end turn and the central portion of the coil spring is less than that of the corresponding spring between the central portion of the coil spring and the associated shortest leg thereof. end turn. The corresponding upper and lower end turns of each coil spring are rotated approximately 180 ° relative to each other, to arrange the longer and shorter legs of the turn of the upper end of each spring in mirror symmetry with the shorter and longer legs, respectively, of the associated lower end turn. By forming the free end of the loop with a relatively small radius, a simple formation of the spring, and subsequently, a simple assembly is allowed. The radius of the smaller leg allows for dimensional stability and allows the turns to be closer together inside the helical bond wire. The radius tends to spring back to its original shape after the helical passes through the connecting jaw, being pressed against the helical connecting spring. These and other objects and advantages of the invention will become more apparent in the following description in the drawings in which: Brief Description of the Drawings Figure 1 is a perspective view of the helical circular spring of the present invention. Figure 2 is a top plan view of two adjacent end turns of the coil springs adjacent to one another connected by the helical wire connection. Figure 3 is a side view, partly cut away, of two coil springs adjacent to each other shown in Figure 3 as an area enclosed in a circle 4. Figure 4 is an enlarged view of the connection between the coil springs . Figure 5 is a top view of the corner of the spring core of the present invention.

Detailed Description of the Invention Firstly referring to Figure 1, there is illustrated a helical coil spring 2 having a central spiral portion 4 composed of a plurality of consecutive helical turns or revolutions 5 defining a central spring axis 6 and ending in a lower end turn 8 and an upper end turn 12. The lower end turn 8 is placed substantially in a plane 10 which is substantially perpendicular to the axis of the central spring 6. The upper end turn 12 is placed substantially in a plane 14 which again is substantially perpendicular to the axis of the central spring 6. The two end turns 8 and 12 are equal, so the description of one end turn will be sufficient for both. The end turns 8 and 12 are aligned relative to the axis of the spring 6, one on top of the other. Each helical section of the helical coil spring wire, which determines the springing and springing property of the coil, extends from the position 16 of the upper end turn down to the position 18 of the lower end turn. With reference to Figure 2, it will be seen that each end turn is generally "U" shaped, and has a relatively long long leg 20 of a length 22 and an arcuate shorter leg 24 which are connected the one with the other by a base net 27 and a portion of an arched section 23, the shorter arcuate leg 24 and the arcuate section 23 being located on the knotless free end of each of the end turns. The arcuate section 23 and the shorter arcuate leg 24 both have a common radius R2 which is substantially smaller than the first radius Rl of the central scroll portion of each coil spring 2. In the preferred embodiment of the invention, the first radius Rl of the central portion of each coil spring is approximately 2.38125 centimeters, while the radius R2 of the arched section 23 and the short arched end of the "U" end is approximately 1.5875 centimeters. Both legs of the end turns in the form of "U" are laterally spaced from the central scroll portion 4 of the coil spring 2. Both, the shorter arcuate leg 24 and the relatively straight longer leg 20, are laterally spaced outward from the central portion 4 of the coil spring. turns 2. The gap D2 between the longer leg 20 and the central portion 4 of the turn spring is smaller than the corresponding distance DI between the central portion 4 of the turn spring and the associated shorter arched leg 24 of the same turn. of end. These separations DI and D2 ensure that, even under extreme load on a helical circular spring 2, the end turns do not come into contact with or collide with the central portion 4 of the coil spring. With reference to Figure 2, the central portion 4 of each coil spring rotates upward until it reaches a first bend 30 in the upper end turn 12. The first fold 30 connects the relatively straight longer leg 20 with the central portion of the coil spring 4. The leg longer relatively straight 20 ends in a second bend 31. The relatively straight longer leg 20 is not completely straight but presents a small arc. The second bend 31 connects the relatively straight longer leg 20 with the base network 27 which is a little curved. On the opposite side of the base net 27 is a third fold 34 with which one end of the arcuate section 23 is connected. The shorter arched leg 24 is much more bent than the relatively straight longer leg 20 or the portion central 24 of the coil spring 2. The shorter arched leg 24 has a length 26 that is smaller than the length of the corresponding longer leg 20, the length being defined for this purpose, as the dimension contained inside the helical binding wire 40. At the other end of the arcuate section 23 is a fourth fold 36 connecting the arched section 23 with a piece of straight tail 28 which it has an end 37. The straight tail part 28 of the top turn is bent downwards out of plane 14, to avoid punctures in the upholstery covering the mattress spring core. The straight tail part 28 of each end turn is also inclined inwardly of the central axis of the spring 6. The straight tail part 28 of each end turn is bent inward towards the center of the turn spring, so as to avoid punctures in the upholstery that covers the core of the spring. The importance of the bent straight tail piece 28 is evident in Figure 3. In Figure 3 it can be seen that the tail piece 28 is bent in the fourth fold 36 inwards, in the direction of the spiral portion. 4 of the coil spring, so that the upholstery does not unravel and also does not come into contact with the central portion 4 of the coil spring. The lower end turn 8 is formed in an identical manner to the upper end turn 12, except that the lower end turn is rotated by 180 ° relative to the upper end turn 12 to arrange the legs, the longest and the shortest one, of the upper end turn 12 of the coil spring, in a mirror symmetry with the longest and shortest legs, respectively of the associated lower end turn 8. Figures 2 to 5 show the method of interconnecting the adjacent coil springs. The adjacent coil springs are connected to each other in the upper and lower end turn by a helical tie wire 40, as shown in Figure 3. The helical tie wires 40 join the relatively straight longer leg 20 an end turn, with a corresponding shorter arched leg of an adjacent end turn. As can be seen in Figure 2, the helical bond wire 40 surrounds the longest leg 20 four times, but the shorter leg bowed only three times. Such an assembly prevents misalignment or misalignment of the spring axis during the formation of the spring core, and provides the possibility for the manufacturer to create a rectangular spring core. During the joining process in the assembly, the shorter arcuate leg of the end turn, which has a small radius R2 on the free end, is trapped between a pair of opposite jaws or attachment matrices that flatten the shortest leg arched with the connecting jaws, and the shorter arched leg returns to its more rounded configuration so that both the longer and shorter leg of the adjacent end turns press outward against the inner surface of the wire of helical connection, thus creating a tight fit inside the helical connecting wire. Figure 5 shows the arrangement of the coil spring 2 in rows and columns. The coil springs 2 are placed in rows side by side 50, and are connected to each other in the upper and lower end turns by helical connecting wires 40. The coil springs 2 are placed in an equal orientation, in such a way that the base net 18 always forms the outer edge of the spring core, resting against the edge wire 52. In the columns of the ends 42 of the spring core, the coil springs are turned in such a way that the end turn that normally is up, is now down. This avoids the problem that the straight tail piece 28 faces the edge of the spring core. In the central portion of the spring core (unlike in the end column), the rows are aligned horizontally, such that the axes of the central springs of the adjacent coil springs form a horizontal line 44. In the same manner, the axes of the central spring of the adjacent coil springs form a vertical line 46. The connecting lines 44 and 46 intersect at the correct angle so that the lateral edges of the spring core form right angles. Because of the formation of these right angles, slippage or incorrect alignment is eliminated, and corrections are not necessary. The spring core is surrounded in the upper and lower planes by upper and lower edge wires 52. A helical connecting spring 60 secures the helical coil spring 2 to the edge wire 52 around the edge of the spring core. Alternatively, metal fasteners or other conventional fasteners may be used to connect the upper and lower end turns of the coils of the spring assembly with the edge springs 52. When creating the spring core as described above, A robust mattress core can be easily assembled with a machine inside an assembly machine. Due to the unique configuration of the end turns of the knotless turns, the repeated precise placement of the end turns of the turns within the joining jaws of the assembly machine is facilitated and the jamming of the machine is minimized. due to incorrect alignment. While we only describe a preferred embodiment of our invention, we do not intend to be limited except by the scope of the appended claims.

Claims

NOVELTY OF THE INVENTION Having described the above invention, it is considered as a novelty, and therefore, the content of the following is claimed as property: CLAIMS

1. A spring core for a mattress, which comprises a plurality of helical coil springs configured identically and each composed of a piece of wire with a central spiral portion of a first radius defining a central loop and ending at the ends opposed with upper and lower end turns without knots, placed in planes substantially perpendicular to the mentioned spiral axes, the mentioned turns being placed in rows side by side, and being connected to each other, in the upper end turns lower mentioned, with helical joining wires placed in the above-mentioned planes, having the upper and lower end turns mentioned a "U" shape, and having a relatively straight longer leg and a shorter arched leg, this arched foot being located shorter at the free end without knots of each of said end turns, and presenting a radi or substantially less than the first mentioned radius of the central spiral portion of the circular springs, the legs of each end turn being laterally spaced apart from the central spring axis, the radial separation between the longer leg and the axis being central spring smaller than the corresponding spacing between the axis of the central spring and the shorter leg of the same end turn, turning the opposite end turns of each spring by approximately 180 ° in relation to each other, to arrange the legs, the longest and the shortest, of the turn of the upper end of the coil spring, in a mirror symmetry with the longest and shortest legs, respectively, of the associated lower end turn.

2. A spring core according to claim 1, characterized in that said central spiral portion has a radius approximately 50 percent larger than the radius of said shorter arcuate leg.

3. The spring core according to claim 1, characterized in that a helical connecting wire four times surrounds one of the relatively straight long legs of a "U" shaped end turn, and surrounds three times to one of the shorter arched adjacent legs of a "U" shaped end turn. The spring core according to claim 1, characterized in that the shorter arched leg of each "U" end turn ends in a piece of straight tail bent inward towards the central portion of each coil spring, outside the plane of the corresponding end turn. 5. The spring core according to claim 1, characterized in that each of the mentioned coil springs is oriented in a similar manner, except for the coil springs immediately adjacent to the opposite ends of the wire of the edge of the coil. spring core. 6. A spring core for mattress, which comprises a plurality of rows arranged side by side, with coil springs of identically configured helical turns, each made of a single piece of wire with a central portion of a first radius defining the axis of the central spring and terminating at the opposite ends with upper and lower end turns without knots arranged in planes substantially perpendicular to the axis of the spring, terminating each turn at a free end, connecting the adjacent springs of the spring core in their turns of upper and lower end by connecting connecting wires, each of these upper and lower turns having substantially a "U" shape, and having a relatively straight longer leg and a shorter arched leg; the said spring core being characterized in that it has a shorter arched leg at the free end of each end turn, and each shorter arched leg having a radius substantially less than the first radius of the central portion of each turn spring. The spring core according to claim 6, further characterized in that each of the coil springs has the shorter arched legs spaced apart from the axes of the central spring at a radial distance greater than the longer legs. relatively straight lines separated from the axes. 8. A knotless wire spring for use in the formation of a spring core for a mattress, said spring comprising a single piece of wire having a central spiral portion of a first radius defining the axis of the central spring and it terminates at the opposite ends in the upper and lower ends without knots, which are placed in planes substantially perpendicular to the axis of the spring, the upper and lower end turns being substantially of a "U" shape, and having a leg longer relatively straight and a shorter arched leg, the shorter arched leg being located at the free end without knots of each of the mentioned end turns, and having a radius substantially smaller than the first radius of the central spring portion of the circular springs, the aforementioned legs of each end turn being separated laterally outwards from the axis of the central spring, the radial ration between the longer leg mentioned and the axis of the central spring smaller than the corresponding spacing between the axis of the central spring and the associated shorter leg of the same end turn, turning the opposite end turns of each spring by approximately 180 ° one in relation to the others, to arrange the longest and shortest legs of the upper end turn of each coil spring in mirror symmetry with the longest and shortest legs, respectively, of the lower end turn associated