WO2005007563A1

WO2005007563A1 - Method of production of innerspring mattresses from steel wire

Info

Publication number: WO2005007563A1
Application number: PCT/GR2004/000040
Authority: WO
Inventors: Panagiotis Anagnostopoulos; Antonios Anagnostopoulos
Original assignee: Panagiotis Anagnostopoulos; Antonios Anagnostopoulos
Priority date: 2003-07-16
Filing date: 2004-07-15
Publication date: 2005-01-27
Also published as: GR20030100304A

Abstract

The present innovation refers to a production method for innerspring mattress units made of steel wire, where the production of the innerspring unit is performed with the positioning of spring cores (2) along the lengthwise side of the mattress. Thus method utilizes a multitude of spring coilers (5) that produce simultaneously all the spring cores (2) of the lengthwise row of the mattress spring cores (2). Subsequently, the spring cores (2) that have been produced with this method are post formed to shape their spring end turns (6) (when this is necessary) and are then subjected to thermal processing (12) Finally, the spring cores (2) are advanced to the assembly station(7) again in a simultaneous manner, where they get interlace amongst themselves and with preexisting there spring cores, utilizing spiral connector wires (3). The spiral connector wires (3) are also produced simultaneously from analogous in number spring forming stations, equal in number to the spiral connector wires needed.

Description

METHOD OF PRODUCTION OF INNERSPRING MATTRESSES FROM STEEL WIRE

TECHNICAL SCOPE OF THE INVENTION

The present innovation refers to a production method for innerspring mattress units made of steel wire raw material. The coil spring assemblies of the type depicted in Figure 1 consist of spring cores (2) situated parallel to one another and in a direction vertical to the plane surface of the mattress and of helical connecting springs (3) that transverse the mattress along the length of one side. Each spring core in the mattress is connected through four connecting spiral lacing wires to its two neighboring spring cores, with this attachment taking place at the end turns of the spring cores.

STATE OF THE ART

Innerspring mattress units have a wide range of application in the manufacturing of mattresses in the seat or couch construction, etc.

Innerspring mattress units are produced by machines that have a common feature. A single spring coiler machine produces serially the spring cores one by one and, if necessary, they have their ends appropriately post formed, thermally processed and subsequently fed serially one after another to an assembly machine, where they are serially interconnected, i.e. the springs are getting attached to one another through a connecting wire piece to the product already processed. The binding medium consists of four spiral lacing wires that connect the upper and lower spring coil end turns between them.

Specifically, the innerspring unit is produced as follows:

The springs are produced by one spring forming head and are then transported either manually or automatically one after another to an assembly machine. There they are positioned in the sequence they are produced into a row of suitable receptor mechanisms, where they are held firmly. Subsequently, two helical spirals are produced and advanced along the length of the attached spring core row and thread the upper and lower end turns of the awaiting to be assembled spring cores, to the corresponding end turns of the previously assembled spring row of the mattress under construction. Subsequently, the already produced mattress portion is advanced by a length analogous to the diameter of the spring cores and the serial advance of the spring cores is continued, as is the serial assembly of the produced spring cores.

According to patent EP0160174, the spring cores that are produced are handed over to a rotating apparatus that has radial arms, which transport the spring cores from workstation to workstation in order to appropriately shape the end spring turns of the spring cores and to thermally process them. Similarly, invention WO0105535 describes a machine with two spring forming heads and two radial mechanisms for processing the spring cores. In both cases, the spring cores are led individually, one at a time, to the assembly station.

Invention US4269300 describes an apparatus that separates stored spring cores and positions them one by one onto an assembly machine. Upon completion of the placement of a whole spring core row, the entire row is interlaced. The same principle is further expounded in invention GB2042467, where a multiple mechanism has the capability to position all the spring cores of a whole mattress row simultaneously. The distance between spring cores is adjustable.

In invention US4413659 a system of two spring forming machines is described with two respective transport belt mechanisms for the transportation of the spring cores to an assembly machine. The two transport belts accumulate the spring cores of each row and feed in an alternate fashion the assembly machine. In all the above three cases, the spring cores are supplied to the assembly machine row by row, so as to attach the whole rows together with two spirally wound lacing wires one at the top and one at the

An additional mechanism that feeds spring cores to an assembly machine is described in invention US4792035, where again the spring cores are separated and fed one by one to an assembly machine.

Inventions DE302721 and DE2923211 describe a weaving mechanism and a mechanism to center the spring cores, in order to thread the row of spring cores with two spiral connecting springs, as described above. Invention EP1124657 further analyzes the spring core forming mechanism, the advance and the stirring mechanisms of the two spiral lacing wires. Finally, invention US4492298 utilizes again two spiral wires (one on top and one at the bottom) to connect two successive spring core rows. The only difference here is that all the spring cores of each row consist of a continuous wire.

These machines lack mainly with respect to the productivity levels achievable, which is restricted both from the productivity of the spring forming machine itself as well as from the advance speed of the lacing wire spiral. The production of the spring cores is limited by the speed of the spring forming head, which produces the spring cores one after another and the lacing of the spring cores in the mattress under construction is limited by the speed of production and the propagation speed of the two processed connecting lacing spirals.

The method of production followed by existing machines restrains their productivity. The need for high productivity leads to the development and production of very fast machines and mechanisms as much in respect to the production of the spring cores themselves, as well as for the production of the spiral lacing wires that presents great complexity, demand specialized materials, lubrication of the spring cores or of the spirals, increased need for maintenance and technical support.

The aim of the present invention is to present a method that can overcome the limitations existing in current methods and machines and to lead to the construction of a machine that is flexible to changing of the product type, adding advantages to the processed product and simultaneously developing high productivity.

PRESENTATION OF FIGURES

Figure 1 Innerspring unit. Figure 2 Production of an innerspring mattress along the direction of the length. Figure 3 Positioning of the rows of spring cores in alternate 180° orientations. Figure 4 Production of an innerspring mattress along the direction of the width. Figure 5 Advancement of spring cores with successive rotational movements. Figure 6 Lengthwise and widthwise mattress rigidity zones. REVELATION OF THE INVENTION

The present invention refers to a method of production of innerspring units that is described below.

There exists a simultaneous, parallel and mass production of spring cores that are produced from a respective in number spring forming heads (5), as shown in Figure 3, which spring cores, after having been appropriately post formed (6), they are thermally processed (12) and subsequently advanced in parallel towards the constructed mattress.

During their transport, the spring cores increase or decrease their in between spacings, depending on the type of mattress that is to be produced.

The spring forming heads have a common motion source that can be a mechanical motion produced by a common rotating cylindrical axle or through transfer of motion with shaft and cam mechanisms or the creation of motion through hydraulic means.

The spring cores are subsequently sheared off by a common command and are moved simultaneously and in parallel with a common mechanism towards the end turn post forming mechanisms (6), if this is necessitated, where they are shaped simultaneously with mechanisms that also have a common motion source.

The shearing off of the spring cores can take place not immediately after they have been formed but at a later stage, after a multitude of spring cores has been formed, connected one with the other. Thus, when shearing off the spring cores after some length, the temporary halt of the rotation of the part bearing the integrated spring cores does not affect the continuing production because there already exists enough rigidity.

The shearing off of the springs is accomplished again with a common energy source, as well as subsequent operations are performed in a mass production mode.

Subsequently, the spring cores are transported simultaneously to the thermal processing stations (12), where they undergo tempering in order to improve their mechanical properties. After the thermal processing stage, a group of ready to be assembled spring cores is advanced in parallel by a common transfer mechanism towards the mattress assembly mechanism.

All the operating spring forming machines develop the mattress with the placement of widthwise rows of spring cores that are weaved together by only two spiral connector wires (3) that move in a direction parallel to the positioned side.

In our method we apply the above practice advancing the mass produced spring cores in the widthwise direction of the processed mattress. Most certainly the speed of production increases significantly vis a vis other methods that utilize one or two spring machines.

Our method finds perfect application in instances where we place the spring core rows along the length side of the innerspring unit that intersets all the helical lacing springs.

Thus, once the spring core row has been positioned in the assembly station, all the lacing wires (3) commence a spiral advance so as to thread in pairs of two each situated spring core with its neighboring one.

The advance of the spiral is only a few centimeters long because they need to cover the diameter of the spring core and an additional extra distance, as determined by the required spacing between successive rows, as shown in Figure 2.

Lacing spirals at the upper and lower end turns of the spring cores 2r-2 in number (where r is the number of spring cores) are situated in suitable positions so that their axial advance meets the spring cores at the contact areas of the upper and lower end spring turns that are to be weaved together.

The mechanisms that produce and advance the lacing spirals, i.e. the lacing spiral forming machines, have a common motion source that can be mechanical via a rotating cylindrical axle or can have cam and shaft mechanisms or hydraulically induced motions.

While the spring cores are held firmly in place, the lacing spirals are produced and advanced, rotated and wrapped around the top and bottom end turns of the spring cores and interlace them. Subsequently, the processed mattress and the assembly station recede from one another by a programmed distance, analogous to the diameter of the spring cores and a new row of spring cores (2a) enters the assembly station and the process continues until the whole innerspring unit is produced.

After the completion of the innerspring unit, the spirals are sheared off with a common command and with common mechanisms and they simultaneously have their ends bent, so as to not be possible to disassemble the innerspring units.

The lacing spirals can be produced simultaneously and advanced at the same time to connect the spring cores with each other or to be prepared ahead of time and to simply be advanced in order to thread together the assemblage spring cores (Figure 4). In every case, the mechanisms of production and forwarded advancement of the spirals, the shearing mechanisms and the spiral spring end bending mechanisms have the same motion source.

The speed of production of a single lacing wire is small due to the concurrent production of all the necessary lacing spirals. Due to the low speed, the lacing wires can be produced without lubrication and, if it is necessary, to be helped in their rotation close to the assembly point.

According to the method, the mattress can be produced and processed along one of its two sides, whichever of the two is chosen. The development along the longer side that is usually the lengthwise side, leads to higher productivity due to the multitude of the simultaneously assembled spring cores.

According to the method, the mattress is being produced as a result of the simultaneous and mass supply of all the spring cores for one side of the mattress. The production, the processes and the transport of the spring cores can be accomplished in different ways that are described subsequently.

The spring cores (2) can be produced with the method of three points, where the wire is fed and led through rollers towards the forming roller that curves the wire into a circle. The pitch of the spring is determined by the tool used. As shown in Figure 3, the spring cores (2) are produced in parallel. Subsequently, they are transported to the station where they undergo shaping of the end turns (6) from the post forming heads, if this is necessary. After the shaping, the spring cores are transported with a rotational motion to the thermal processing station, where they undergo tempering (12). Finally, the spring core row is transported with a 180° revolution (9) to the assembly station (7), where they are interweaved with the processed mattress through the lacing spirals (3).

The produced spring cores can be rotated about their axis with a suitable mechanism either 90° clockwise or 90° counter clockwise. This is done in an alternating fashion for the lengthwise rows. The revolution serves two objectives. One is that with the 90° revolution the post formed upper and lower spring core end turns come into contact with the ends of adjacent spring cores and are thus ready to be threaded with the spiral wires. The other objective is to ensure that the mattress recesses vertically at the points where it is compressed, because by their construction the spring cores have the tendency to recess in an oblique direction.

With the positioning of the widthwise spring cores with a change in the orientation of the heads by 180°, we achieve a neutralization of these tendencies.

The method is suited for the production of mattresses with zones of varying rigidity, perpendicular to the production direction of the mattress, Figure 6. The different rigidity of the mattress is achieved with the variation in the characteristics of the spring cores. For example, varying the diameter of the wire of the spring cores of each zone, we change the coefficient constant of the spring core and as a result, the rigidity of the mattress. We achieve the same result by modifying other characteristic variables of the spring core such as the number of spring turns or the diameter of the internal spring turns.

During mattress production, after the assembly of a spring core row, the already produced mattress portion and the assembly mechanism recede from one another. Alternatively, the assembly mechanism can be stationary and the processed mattress can recede or the assembly mechanism can move while the produced mattress is developed, whose produced rows remain stationary. ADVANTAGES OF THE METHOD

The method is characterized by its high productivity, because the multitude of the spring forming coiling stations produce simultaneously a large number of spring cores and also the lacing spiral wires need to travel only a few centimeters of length, as shown in Figure 2, as compared to the travel of one or two meters that a pair of spiral lacing wires travels in older methods.

The method leads to the development of a machine with high productivity, whose mechanisms cooperate at a low speed and thus operate with reliability and decreased wear and tear.

According to the method, mattresses can be produced along the long side, an aspect that increases the productivity of the machine.

The method leads to the development of a machine that is extremely flexible, because it produces mattresses of varying sizes without adjustments. If the springs are produced along their long dimension, the change in width is achieved easily with adjustment of the length of spiral lacing wire span that connects the lengthwise rows.

The method leads to the development of a machine that without any adjustment can produce mattresses with different zones of rigidity in the direction of the length (11) as well as in the direction of the width (11) of the mattress, as shown in Figure 6.

This is achieved by the following combinations:

1. production of a widthwise row of spring cores utilizing wires of different thicknesses for each spring coiler. 2. Production of spring cores in a widthwise row with spring cores of different diameters or pitch through the activation of a special mechanism in each spring coiler. 3. Production of widthwise rows of spring cores with regulated distances between them.

In this manner, we can produce mattresses with zones of different rigidity in the lengthwise and widthwise positions. Also, we can produce one or more perimetric rows of each mattress with higher rigidity.

In the upper and lower mattress end rows we make use of wire of greater thickness in the spring coilers, so that the produced spring cores have higher rigidity. In the lengthwise end rows we use the spring core production methods applying smaller diameter or having spring cores with greater pitch.

APPLICATION OF THE INVENTION

A possible embodiment of the invention is the following:

All the spring cores of a lengthwise mattress row are produced simultaneously from a respective number of spring coilers (5) that have a common motion source to attract the wires (4) from the corresponding wire supply stations and the formation of the spring turns of the spring cores of the row with suitable adjustments, so as to achieve at each point in the row the rigidity needed by creating a spring form of proper diameter and pitch from wires of appropriate thicknesses for each production position in the row. Thus, each row is produced with positions of different rigidity values along its length.

The formed spring cores are subsequently sheared off from the continuous wire batch with a common command and a common mechanism, are then transported simultaneously and in parallel to a workstation where they are post formed by specially constructed presses to create the desired profile of the two free end turns of each spring core, this function also being achieved through a common motion source. Subsequently, the spring cores are transported as a group to the workstation, where there are thermal processing stations to temper them (12).

After having been heat treated, the spring cores are picked up by a special mechanism, where the spring cores have their in between distances adjusted, increasing or decreasing their interspacings, depending on the type of mattress. Following that, the produced spring cores can be rotated about their vertical axis with a suitable mechanism either 90° clockwise or 90° counterclockwise. This is done alternatively in the lengthwise rows so as to bring the end turns of successive spring cores in the proper position to be interlaced. Simultaneously, facing the above mentioned mechanisms there exists a row of mechanisms that forms the spiral springs that interweave between them in pairs, the neighboring spring cores through their upper and lower free ends.

The lacing spirals are formed after pulling the necessary raw materials and these spiral forming mechanisms are situated on a moving carrier that travels in the same line with the production line of the spring cores and moves towards them.

Following this stage, the spring cores are positioned at the workstation, where the assembly of the mattress commences. With a weaving method the end turns of the spring cores are threaded between them at the top and bottom. The spirals in an advancing and rotating motion wrap around the upper and lower end turns of the spring cores and interlace them.

Subsequently, the produced row is advanced by a desired length and the spirals by rotation are ready to accept a new lengthwise row of spring cores.

This process is repeated until the whole innerspring mattress is completed.

At the end of the process the lacing spirals are sheared off with a common command and with common mechanisms their ends are bent, so as not to be possible to disassemble the produced mattress.

Also, it is feasible to process the mattress along the direction of the width, so that the produced spring core rows represent rows along the width dimension.

Claims

1. Method of production of mattresses (1) made of spring cores arranged in rows, where each spring core (2) of the row is interlaced with spiral connector wires (3) at its upper and lower end turns with its two neighboring spring cores of the same row, which spiral connector wires thread simultaneously each side of the row with the preceding or succeeding one through part of their length, spanning thus the whole width of the mattress that is characterized by the fact that the innerspring unit is produced by adding the spring core row either along the widthwise direction of the mattress or along the lengthwise direction, where in both cases the spring cores are produced by more than three spring forming machines (5) but in preference of as many as the spring cores of the produced row, the mattress being produced by adding subsequent rows in the lengthwise side, where the spring cores (22) acquire through a suitable mechanism the appropriate distances between them, then all the spiral connector wires (3) that need to be contained in the mattress at the upper and lower side, which are double the number of the spring cores of the lengthwise row, are positioned at the interlacing points and via a suitable mechanism are set in simultaneous axial rotation that forces them to spirally advance, so that they all simultaneously interset at right angles the spring core row, threading as a result neighboring spring cores at the upper and lower contacting spring elements.

2. Method as described in Claim 1 that is characterized by the fact that during the lengthwise positioning of the rows of spring cores, the respective spring coilers (5) produce spring cores with different rigidity, so as to create automatic widthwise zones (11) of varying rigidity.

3. Method as described in Claim 1 that is characterized by the fact that the spring coilers (5) that each produces the spring cores for each position of the row, can have a common source of motion for their simultaneous or in group operation, which operation involves the simultaneous pull of all the spring wire raw materials (4), the common mechanism that controls the formation of the diameters of the produced spring cores, the creation of their pitch, as well as a common energy source for the shearing off of the spring cores.

4. iViethod as described in Claim 1 that is characterized by the fact that the spring cores can be transported to the assembly station (7) through a transport carrier system, separate for each spring core that commences operation at the production station of the spring core and stops at the spring core transfer station that is changing according to the desired density between the spring cores of each row, where the starting point for each transportation carrier is fixed and is the production station for the spring and the ending stop point of the transport carrier system is adjustable, situated in a parallel line to the position where the spring cores are interlaced.

5. Innerspring mattress unit with different zones of rigidity that is characterized by the fact that all the widthwise rows of spring cores are being produced from separate spring coilers (5), where each one can be produced from different thickness wires as well as of spring cores that have different diameters and spring cores with a different pitch, imparting thus the capacity to create many widthwise zones of varying rigidity (11), as many as the rows themselves. There also exists simultaneously and selectively at the same spring coiler stations, the capacity to produce spring cores with different diameter and different pitch, creating thus automatically lengthwise zones with programmable variable rigidity, being capable for the distances between all the lengthwise rows of spring cores that are held in position by the helical connecting springs that interlace them, to be adjusted through a variation of the length of the spiral connector wires, so as to regulate the density of the lengthwise rows, adding another capability to create lengthwise zones of selectable rigidity, creating also the external rigidity zones in the mattress in one or multiple, widthwise or lengthwise, spring core rows with the utilization at the end widthwise row of spring cores with larger diameter wire and the first and last lengthwise rows to make cumulative usage of the spring core processing methods, having spring cores of smaller diameter with greater pitch and smaller distances between rows, being capable for each lengthwise row to have the spring cores rotated about their axis by 180° in relation to the spring cores of the preceding or succeeding row, alleviating their in between tendency that the spring cores have to deflect sideways they are then compressed.