Background of the invention
[0001] The invention relates to a method of producing a spring insert from strings of springs
which are individually encased in a pocket of material, so-called pocketed springs,
said strings having an adhesive applied and being compressed to form the spring insert,
said strings having different resiliency and/or damping characteristics, and said
strings are cut from at least one length, and where each length is fed to a cutting
mechanism.
[0002] The said method is known from EP-A-0089789, and by this known method it is possible
in a surprisingly simple manner to produce a spring insert with ideal characteristics,
in that there can be built up a spring insert which is in accordance with the load
on the individual parts of the spring insert. This permits production of spring inserts,
and herewith mattresses, cushions etc., which are in complete accordance with the
degree of support they are desired to provide.
[0003] Further another method is known from EP-A-0421495 which method involve the following
steps and features in producing a spring insert:
A string is cut from a length in a cutting device to which several lengths are supplied,
and each length is fed to a cutting mechanism by means of an adjustable feeding arrangement
in such a manner that the selection of the length and the length of the string can
be adjusted,
an adhesive is applied to the string during its movement past one or more nozzles
before the compression,
the adhesive is applied only to the outer side of the pockets where pockets of abutting
strings lie up against each other after the compression,
and the adhesive is pumped out through the nozzle(s) in a jet on the outer side of
the pocket when the pocket is opposite the nozzle(s).
[0004] However, none of the mentioned applications shows a suitable way of orienting the
length before applying the adhesive so that the lengths and the strings can be conveyed
without risk for being displaced in relation to the support and one another.
Advantages of the invention
[0005] With the method according to the invention, this can be effected in a simple manner,
such as disclosed in the characterising portion of the claim, when the lengths are
arranged so that they are fed with the longitudinal axes of the pocket-springs being
horizontal, and thereafter the string are tipped 90° before applying the adhesive,
whereby the length and the string are conveyed without risk of displacement in relation
to their support or one another.
The drawing
[0006] In the following section, an example of a plant for the execution of the method will
be described in more detail with reference to the drawing, where
- fig. 1
- shows a perspective drawing of a plant according to the invention,
- fig. 2
- shows the actual cutting-off device with the one length in use,
- fig. 3
- shows the cutting-off device with a second length in use,
- fig. 4
- shows the turntable before the turning of the string,
- fig. 5
- shows the turntable during the turning of the string,
- fig. 6
- shows the actual compression device before the compression of a string with adhesive
applied, and
- fig. 7
- shows the compression of the string against the remaining strings during the production
of a spring insert.
Description of the example embodiment
[0007] A plant for the execution of the method is illustrated in fig. 1.
[0008] The plant comprises a feeding section 1, which will be described in more detail with
reference to figs. 2 and 3, a turning section 2, which will be described in more detail
with reference to figs. 4 and 5, and an adhesive application section 3 and a compression
section 4 which will be described in more detail with reference to figs. 6 and 7.
[0009] As shown in figs. 2 and 3, the feeding section 1 consists of a frame 5, on the top
of which are supported a number of wheels 6 corresponding to the number of pocket-spring
lengths 7, 8.
[0010] These lengths 7 and 8 can have different resiliency and/or damping characteristics,
so that in the example embodiment shown there can be produced a finished spring insert
9 consisting of two different types of pocket-springs.
[0011] The wheels 6 are preferably sprocket-formed so that the lengths 7 and 8 can be fed
by rotation of the wheels. In order to prevent the lengths 7 and 8 from jumping out
of the wheel 6, a shield 10 can be mounted over a part of the wheels' circumference.
[0012] Under each set of wheels 6 there is mounted a further set of drive rollers 11 for
each length 7, 8, so that each individual length can be fed in a precise manner. In
practice, the wheel sets 6, 11 will be synchronized by means of a chain drive or the
like.
[0013] Under the drive roller 11 there is mounted a cutting mechanism 12 comprising two
jaws 13 which can be moved in a reciprocating manner by means of an actuator 14, so
that the lengths 7 and 8 can be fed between the jaws 13 when these are separated.
[0014] In this position, the drive roller 11 can feed a certain number of pockets in the
length 7 and 8 so that a given number of pockets, corresponding to the length of the
string 15, will form one element in the finished spring insert 9.
[0015] When the string 15 has been formed, the jaws 13 are closed and the length is cut
over either mechanically or thermally.
[0016] Below the cutting mechanism 12 there is mounted a conveyor belt 16. This conveyor
carries the string 15 further to an angularly-extending belt 17 which leads the string
15 forward to the turning section 2.
[0017] As shown in figs. 4 and 6, this section is configured with a conveyor belt 18 on
which the string 15 is fed forward in the section.
[0018] When the belt 18 is stopped, a boom 19 operated by actuators 20 pushes the string
over the side where it falls down on a side-stop 21. As shown in fig. 5, the side-stop
is thereafter tipped so that the string falls down into a gutter 22.
[0019] In the gutter 22, the string 15 is fed into a chain conveyor 23 which is moved from
the turning section 2 and further through the compression section 4.
[0020] Hereafter, the conveyor 23 feeds the string 15 past an adhesive application device
24 which can be of any suitable type.
[0021] A fluid adhesive is advantageous, the reason being that this can be pumped out through
nozzles via a pipe 25. This makes it possible for the adhesive to be pumped out in
shots, and the adhesive 26 can hereby be applied to the outer side of each pocket-spring
in the string as this passes the nozzle(s).
[0022] The chain conveyor 23 stops when the string 15 is standing opposite a pusher arm
27, this being provided with an end profile which enables it to lie up against the
string 15.
[0023] Hereafter, an actuator 28 can feed the string 15 with adhesive 26 on to an underlayer
29 where it can be pushed up against preceding strings for gluing together with the
outermost string.
[0024] The spring insert 9 is hereby built up of strings 15 which one after another are
glued together to form the finished insert 9.
[0025] When the last string 15 has been glued on, the belt 29 is started and the spring
insert is led away.
[0026] The following is a description of the method.
[0027] The lengths 7 and 8 with the desired resiliency and damping characteristics and dimensions
are fed to the plant in the form of endless lengths of pocket-springs 7 and 8.
[0028] In the example shown there are two lengths with the same outer dimension, but there
will be nothing to prevent the use of several lengths and lengths with other dimensions.
There can hereby be produced spring inserts of any desired kind and character, also
including spring inserts comprising pocket-springs of different heights.
[0029] The plant is controlled in a commonly-known manner by microprocessors so that it
is possible to select to feed strings of any desired length, said strings then being
tipped upright and receiving an application of adhesive before the final compression.
[0030] The whole method is controlled so that all movements are synchronized, whereby strings
can be produced at a very high rate of production, the reason being that the whole
of the flow can be effected at the same tempo.
[0031] The choice of pocket-spring strings is determined by the activation of the sets of
feeding wheels, whereby strings can be produced at normal rates of production, even
when there are frequent changes between the strings.
1. Method of producing a spring insert from strings of springs which are individually
encased in a pocket of material, so-called pocketed springs, said strings having an
adhesive applied and being compressed to form the spring insert, said strings (15)
having different resiliency and/or damping characteristics are used, where said string
(15) is cut from at least one length (7, 8), and where each length is fed to a cutting
mechanism (12, 13), characterized in that the length(s) (7, 8) are fed over wheels/sprockets (6, 11) with horizontally-extending
axes to the cutting mechanism (12, 13), after which the string (15) is fed in a commonly-known
manner on to a turning table (2) where the string (15) is tipped upright, whereafter
the string (15), by means of a chain conveyor (23) in the form of an endless chain
over carrier wheels with vertical axes, is fed past the adhesive application nozzle(s)
(24) before being positioned on a horizontally-displaceable arm (27) which thereafter
presses the string (15) up against the preceding string in the spring insert (9).
1. Verfahren zum Herstellen eines Federeinsatzes aus Reihen von Federn, die einzeln in
Materialhülsen gekapselt sind, sogenannte gekapselte Federn, wobei die genannten Reihen
einen Klebstoffauftrag aufweisen und verpreßt werden, um den Federeinsatz zu bilden,
und die genannten Reihen (15) verschiedene Elastizitäts- und/oder Dämpfungscharakteristiken
aufweisen und die genannte Reihe (15) von mindestens einer Bahn (7, 8) abgeschnitten
wird, wobei jede Bahn einer Schneidvorrichtung (12, 13) zugeführt wird, dadurch gekennzeichnet,
daß die Bahn(en) (7, 8) über Rollen/Kettenräder (6, 11) mit horizontal sich erstreckenden
Achsen zu der Schneidvorrichtung (12, 13) geführt werden, nach welcher die Reihe (15)
in einer an sich bekannten Weise zu einem Drehtisch (2) geführt wird, wo die Reihe
(15) aufrecht gekippt wird, wonach die Reihe (15) mittels einer Kettenfördervorrichtung
(23) in Form einer Endlos-Kette, die über Trägerrollen mit vertikalen Achsen läuft,
geführt wird, vorbei an der(n) Klebstoffauftragedüse(n) (24), bevor sie auf einem
horizontal verschiebbaren Ausleger (27) positioniert wird, der danach die Reihe (15)
gegen die vorhergehende Reihe im Federeinsatz (9) preßt.
1. Procédé pour produire un insert élastique à partir de chapelets de ressorts qui sont
enveloppés individuellement dans une poche de matière, appelés ressorts ensachés,
ces chapelets ayant un adhésif qui leur est appliqué et étant comprimés pour former
l'insert élastique, lesdits chapelets (15) utilisés ayant des caractéristiques d'élasticité
et/ou d'amortissement différentes, dans lequel lesdits chapelets (15) sont coupés
à partir d'au moins une longueur (7,8) et dans lequel chaque longueur est acheminée
à un mécanisme de coupe (12, 13), caractérisé en ce que les longueurs (7, 8) sont
acheminées par l'intermédiaire de roues/pignons (6, 11) avec des axes horizontaux
vers le mécanisme de coupe (12, 13) après quoi le chapelet (15) est acheminé d'une
manière usuelle sur une table de pivotement (2) où le chapelet (15) est redressé par
basculement, après quoi le chapelet (15), au moyen d'un convoyeur à chaîne (23) sous
la forme d'une chaîne sans fin montée sur des roues porteuses à axes verticaux, passe
devant au moins une buse d'application d'adhésif (24) avant d'être positionné sur
un bras déplaçable horizontalement (27) qui presse ensuite le chapelet (15) contre
le chapelet précédent dans l'insert élastique (9).