U.S. patent application number 15/753046 was filed with the patent office on 2018-09-06 for spring, spring core and method for producing the same.
This patent application is currently assigned to AGRO HOLDING GMBH. The applicant listed for this patent is AGRO HOLDING GMBH. Invention is credited to WOLFGANG GROTHAUS.
Application Number | 20180249842 15/753046 |
Document ID | / |
Family ID | 56550871 |
Filed Date | 2018-09-06 |
United States Patent
Application |
20180249842 |
Kind Code |
A1 |
GROTHAUS; WOLFGANG |
September 6, 2018 |
SPRING, SPRING CORE AND METHOD FOR PRODUCING THE SAME
Abstract
A spring for a spring core, wherein the spring has helical
windings and a first end winding and a second end winding, wherein
at least the first end winding has a free end and the free end has
at least one passage and the opening of the passage is directed
outwardly with respect to the end winding of the spring, is
distinguished by the fact that the passage is inclined out of a
horizontal plane preferably about an angle .alpha. in the
compression direction of the spring.
Inventors: |
GROTHAUS; WOLFGANG; (BAD
ESSEN, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AGRO HOLDING GMBH |
BAD ESSEN |
|
DE |
|
|
Assignee: |
AGRO HOLDING GMBH
BAD ESSEN
DE
|
Family ID: |
56550871 |
Appl. No.: |
15/753046 |
Filed: |
July 25, 2016 |
PCT Filed: |
July 25, 2016 |
PCT NO: |
PCT/EP2016/067669 |
371 Date: |
February 15, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A47C 27/065 20130101;
A47C 27/07 20130101 |
International
Class: |
A47C 27/06 20060101
A47C027/06; A47C 27/07 20060101 A47C027/07 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 20, 2015 |
DE |
10 2015 113 857.3 |
Claims
1. A spring core (1, 10) comprising at least two springs (2, 20)
and at least two connecting springs (3), with which the at least
two springs (2, 20) are connected, wherein the springs (2, 20)
comprise spiral windings and a first end winding (201, 2001) and a
second end winding (202, 2002), wherein at least the first end
winding (201, 2001) has a free end (203, 2003) and the free end
(203, 2003) has at least one passage (204, 2004) and an opening of
the passage (204, 2004) is directed to the outside with respect to
the end winding (201, 2001 or 202, 2002) of the spring (2, 20),
wherein the passage (204, 2004) is inclined from a horizontal plane
by an angle .alpha. in the compression direction of the spring (2,
20), wherein the angle .alpha. is 5.degree. to 25.degree..
2. The spring core (1, 10) according to claim 1, wherein the angle
.alpha. is 10.degree. to 15.degree..
3. The spring core (1, 10) according to claim 1, wherein the
passage (204, 2004) is V-shaped or U-shaped.
4. The spring core (1, 10) according to claim 1, wherein the
passage (204, 2004) is arranged in such a way in the free end (203,
2003) of the first end winding (201, 2001) or the second end
winding (202) that an offset (213) is obtained between an apex
(214) of the passage (204) and a central plane X-Y of the spring
(2, 20) in the arrangement direction of the central axis of a
connecting spring (3).
5. The spring core (1, 10) according to claim 1, wherein the free
end (203, 2003) has a curvature.
6. The spring core (1, 10) according to claim 1, wherein the
curvature of the free end (203, 2003) is smaller than the curvature
of the remaining resilient windings of the spring (2, 20).
7. The spring core (1, 10) according to claim 1, wherein the free
end (203, 2003) in the assembled state of the spring core (1, 10)
touches the inner diameter of the connecting spring (3) with a
two-point contact or a three-point contact.
8. The spring core (1, 10) according to claim 1, wherein that the
last winding (209) before the end winding (201, 2001 or 202) has a
section (210) in which the diameter of the last winding (209)
increases continuously.
9. The spring core (1, 10) according to claim 1, wherein the
increase in the diameter for this section (210) is preferably in a
range of 5% to 30%, particularly preferably from 15% to 20%, based
on the diameter of the remaining resilient windings of the
spring.
10. (canceled)
11. The spring core (1, 10) according to claim 1, wherein the
orientation of the springs (2, 20) alternates per row or column, so
that two adjacent springs (2, 20) are each connected in pairs with
their free end (203, 2003) or with their indentation (205, 2005) of
the first end winding (201, 2001) or the second end winding (202,
2002) by a connecting spring (3).
12. The spring core (1, 10) according to claim 1, wherein the
respective last spring (2, 20) of a row or a column of the spring
core (1, 10) is oriented in such a way that it is arranged relative
to the adjacent spring (2, 20) rotated by about 180.degree. about
its vertical axis.
13. A method for producing a spring core (1, 10) according to claim
1, characterized by the following method steps: a) providing a
spring steel wire; b) producing the resilient windings and the
first end winding (201, 2001) and the second end winding (202,
2002) of the spring (2, 20), and in each case the last resilient
winding (209) before the first end winding (201, 2001) and the
second end winding (202, 2002) with the respectively defined
section (210); c) producing at least one bend, in particular a
V-shaped or U-shaped passage (204, 2004) and/or the indentation
(205, 2005) in the first end winding (201, 2001) of the spring (2,
20); d) connecting two respective springs (2, 20) at their
respective first end winding (201, 2001) and at their respective
second end winding (202, 2002) with a connecting spring (3) to form
a spring core (1, 10).
14. The method for producing a spring core (1, 10) according to
claim 13, wherein after the method step c) the following method
step takes place: producing at least one bend, in particular the
V-shaped or U-shaped passage (204, 2004) and/or the indentation
(205, 2005) in the second end winding (202, 2002) of the spring (2,
20).
Description
[0001] The present invention relates to a spring, a spring core and
a method for its manufacture.
[0002] Springs for open spring cores such as so-called Bonell or
light spring cores for the manufacture of mattresses or cushions
are known from the state of the art. Open spring cores have the
essential characteristic of a more flat distribution of forces that
a user exerts on the core, as opposed to pocket spring cores. This
means that when using such an open spring core, more springs
deflect per unit area than with a comparable pocket spring
core.
[0003] This property is achieved, for example, by the connection of
a row of springs of an open spring core through a respective
connecting spring, which open spring core extends in a is column or
row of the open spring core. The connecting spring connects the
free ends of the springs by twisting or winding around the free
ends. A pocketing or complete encapsulation of each individual
spring of the spring core by a non-woven fabric for example--as is
the case with a pocket spring core--therefore does not take place
with open spring cores.
[0004] The spring core is usually rolled up after completion to
achieve a smallest possible, space-saving packing size for
shipping. In order to ensure trouble-free handling during further
processing of the spring cores into mattresses or cushions,
measures must be taken because of the absence of pockets in order
to avoid hitching of respectively adjacent springs of the spring
core when the spring core is compressed during the rolling-up
process or when the spring core is extended when handling the
spring core during further processing of the spring core into
mattresses or cushions.
[0005] For this reason, the spring core is covered with a layer of
wrapping paper before the rolling-up process. However, this measure
is often not sufficient to avoid hitching of the springs during the
rolling-up process. Therefore, various measures are known from the
state of the art to avoid hitching of the springs of the spring
core during the rolling-up process.
[0006] According to EP 2 719 307 A1 it is provided that the free
end of the end winding of a spring is extended in a straight
direction and provided with at least one V-shaped or U-shaped
passage. The V- or U-shaped passage is intended to prevent the end
windings of the springs from coming out of the connecting spring.
So-called light spring cores are also known from the state of the
art, which solve this by a further spring leg.
[0007] In the following, the term "passage" refers to the result of
a penetration by forming of a section of a spring steel wire from
one plane or surface to another plane or surface.
[0008] These and other measures have also improved the handling of
a spring core during further processing of the spring cores into
mattresses or cushions according to the technical teaching of EP 2
719 307 A1, so that hitching of the springs occurs less frequently
during the rolling-up process, but this state of the art technology
also provides cause for further optimisation.
[0009] Accordingly, it is the object of the present invention of
further improving the manageability of a spring core when further
processing the spring cores into mattresses or cushions and, in
particular, to further reduce the possibility of hitching the
springs when rolling up the spring core and/or when handling the
spring core during further processing of the spring core into
mattresses or cushions.
[0010] This object is achieved by the invention by a spring of
claim 1, a spring core of claim 11 and a method according to claim
14.
[0011] Accordingly, it is intended that the passage is preferably
inclined by an angle .alpha. in the compression direction of the
spring from a horizontal plane in relation to the installation
position.
[0012] The invention is thus based on the idea of arranging a
passage in such a way that the passage forms a "deflector" inclined
into the spring, which prevents a first end winding and the
remaining resilient windings of the spring from hitching when the
spring is compressed, e.g. during the packing process.
[0013] The inclination of the passage in the compression direction
of the spring further advantageously creates an inclined sliding
plane, which optimises the deflector function of the passage
advantageously, so that with high probability hitching of the
passage with the other resilient windings of the spring is
prevented.
[0014] In one embodiment of the invention, the first end winding
and the second end winding of the spring have a free end. The free
end has a curvature smaller than the curvature of the other
resilient windings of the spring.
[0015] Due to the curvature of the free end of the first end
winding or the second end winding, the free end in the assembled
state of the spring core touches the side of a connecting spring,
which forms the inner diameter of the connecting spring, in a
two-point contact or three-point contact.
[0016] This ensures advantageously a defined position of the spring
relative to the connecting spring, wherein the free end of the
first end winding or the second end winding can carry out a
rotational movement relative to the connecting spring when the
spring is compressed.
[0017] In a further embodiment of the invention, the first end
winding and the second end winding each have a reciprocal
indentation.
[0018] Due to the indentation, the connecting plane of the
respective end winding with the respective connecting spring is
arranged outside the outer diameter of the respective end winding.
This allows the end windings to respectively accommodate the
remaining part of the spring in an advantageous manner when being
compressed during the rolling-up process, when the spring almost
retracts to the block, so that the mutual jamming of neighbouring
springs between the spring windings moving towards each other in
the vertical direction during the compression of the spring can be
avoided to the highest possible extent.
[0019] In another embodiment, the first end winding and the second
end winding of the spring have an indentation. The topology of the
indentation is reminiscent of a bus stop bay. Due to the
indentation, the connection section of the first and second end
winding is advantageously designed in such a way that it lies
outside the outer diameter of the first end winding or second end
winding.
[0020] In another embodiment of the invention, the spring comprises
a last resilient winding before the first end winding or before the
second end winding, which is wound in such a way that its diameter
continuously increases within a half winding in a defined section
of the last resilient winding.
[0021] The increase in diameter for this section is preferably in a
range of 5% to 30%, especially from 15% to 20%, based on the
diameter of the other resilient windings of the spring.
[0022] This allows the end windings to respectively accommodate the
remaining part of the spring in an advantageous manner during the
rolling-up process, when the spring almost retracts to the block,
so that the mutual jamming of neighbouring springs between the
spring windings moving towards each other in the vertical direction
during the compression of the spring can be avoided to the highest
possible extent.
[0023] The spring according to the invention results in a spring
core in which a hitching of springs during the packaging process is
advantageously avoided to the greatest extent possible.
[0024] Further advantageous embodiments of the invention can be
found in the subclaims.
[0025] The invention is described below with reference to the
enclosed figures, wherein:
[0026] FIG. 1: shows a section of a spring core in accordance with
the invention with a plurality of springs according to the
invention;
[0027] FIG. 2: shows an enlargement of a section of a connection of
two springs through a connecting spring in the spring core
according to FIG. 1;
[0028] FIG. 3: shows an enlargement of a section of a front view of
a spring of a spring core from FIG. 1;
[0029] FIG. 4: shows a top view of a spring of a spring core from
FIG. 1;
[0030] FIG. 5: shows a top view in the sectional view of an end
winding of a spring of a spring core from FIG. 1;
[0031] FIG. 6: shows a top view of an end winding with an
embodiment variant of a free end of s a spring inserted into a
spring core as shown in FIG. 1;
[0032] FIG. 7: shows a top view of another embodiment variant of a
free end of a spring inserted into a spring core as shown in FIG.
1;
[0033] FIG. 8: shows a top view of an embodiment variant of a
respective first end winding of two springs of a spring core
arranged next to each other;
[0034] FIG. 9: shows a top view of a respective second winding of
two springs of a spring core arranged adjacent to each other.
[0035] FIG. 1 shows a spring core 1 for mattresses or cushions. The
spring core 1 has a plurality of springs 2, which are arranged side
by side or below each other in rows and columns. The springs 2 are
spirally wound springs made of spring wire with a round
cross-section.
[0036] The spring 2 respectively has a first end winding 201 at its
respective one end and respectively a second end winding 202 at the
respective other end. The springs 2 are alternately mutually
inserted into the spring core 1. In this respect, the springs 2 are
arranged in the spring core 1 in such a way that the first end
winding 201 is respectively arranged next to the second end winding
202.
[0037] The first end winding 201 and the second end winding 202
each have a diameter greater than the remaining part of the spring
2. Thus the spring 2 has a progressive spring characteristic curve.
Due to the larger diameter, the end windings 201,202 can each take
up the remaining part of the spring 2 during compression during the
rolling-up process, when the spring 2 almost retracts to the block,
so that due to the increased diameter of the end windings 201, 202
the mutual jamming of neighbouring springs 2 between the spring
windings moving towards each other in the vertical direction during
the compression of the spring 2 can advantageously be avoided to
the highest possible extent.
[0038] The first end winding 201 and the second end winding 202 of
springs 2 respectively arranged adjacent to each other in the
spring core 1 are connected to each other by a respective
connecting spring 3. The connecting spring 3 is a spiral wound
spring with a round wire cross-section. The connecting spring 3
preferably has a lead greater than the wire diameter of the
connecting spring 3. The connecting springs 3 can be arranged in
row or column direction of the spring core 1. However, an
arrangement of the connecting springs 3 in line direction of the
spring core 1, i.e. transverse to the longitudinal extension of the
spring core 1, is preferred.
[0039] The connecting springs 3 and the absence of pockets, in
which a spring of a spring core is inserted in each case and by
which a spring is respectively enclosed, characterize the spring
core 1 as the so-called Bonell spring core.
[0040] FIG. 2 shows an enlarged section of a connection of two
springs 2 by a connecting spring 3 in the spring core 1 according
to FIG. 1. FIG. 2 clearly shows how the connecting spring 3
connects the first end windings 201 and the second end winding 202
of two springs 2.
[0041] The first end winding 201 of the spring 2 has a free end
203. The free end 203 of the first end winding 201 has a curvature
smaller than the curvature of the other resilient windings of the
spring 2.
[0042] Due to the curvature of the free end 203 of the first end
winding 201, the free end 203 in the assembled state of the spring
core 1 touches the inside of the connecting spring, i.e. the side
of the connecting spring 3 which forms the inner diameter of the
connecting spring 3, in a two-point contact or in a three-point
contact.
[0043] This ensures advantageously a defined position of the spring
2 relative to the connecting spring 3, wherein the free end 203 of
the first end winding 201 can rotate relative to the connecting
spring 3 when the spring 2 is compressed.
[0044] The free end of the end winding 201 also has a V-shaped
passage 204. The passage 204 can alternatively also be U-shaped.
The V-shaped passage 204 is arranged in the free end 203 of the
first end winding 201 in such a way that the opening of the "V" is
directed outwards with respect to the first end winding 201 of the
spring 2.
[0045] The V-shaped passage 204 is inclined from a horizontal plane
preferably by an angle .alpha. of 5.degree. to 25.degree.,
particularly preferred by an angle .alpha. of 10.degree. to
15.degree. in the compression direction of the spring 2 (see also
FIG. 3).
[0046] By the arrangement of the V-shaped or U-shaped passage, in
such a way that a "deflector" inclined into the spring 2 is formed
by the passage 204, there is a high to probability that hitching of
the first end winding 201 and the remaining resilient windings of
the spring 2 is prevented, for example, during the packing process.
In addition, the inclination of the passage 204 in the compression
direction of the spring 2 advantageously creates an inclined
sliding plane, which optimizes the deflector function of the
passage 204 advantageously, so that with high probability hitching
of the passage 204 with the other resilient windings of the spring
2 is advantageously prevented.
[0047] The free end 203 of the first end winding 201 is wound
around by the connecting spring 3, so that the free end 203--with
the exception of the V-shaped or U-shaped passage 204--is within
the clear inner diameter of the connecting spring 3.
[0048] The free end 203, around which the connecting spring 3 is
wound or coiled, acts in combination with the connecting spring 3
as a hinge-like connection between the spring 2 and the connecting
spring 3.
[0049] The hinge action results in a largely vertical compression
of the spring 2, as the free end 203 can rotate relative to the
connecting spring 3, so that this "hinge effect" also makes an
advantageous contribution to preventing the resilient windings from
hitching when the spring 2 is compressed, since the spring 2 is not
deflected out of the vertical during the compression process.
[0050] The second end winding 202 of the spring 2 has an
indentation 205. The topology of the indentation is reminiscent of
a bus stop bay. The indentation 205 has a first leg section 206, a
second leg section 207 and a connection section 208. Due to the
indentation 205, the connecting section of the second end winding
202 is advantageously designed in such a way that it lies outside
the outer diameter of the second end winding 202.
[0051] The connecting section 208 has a curvature which is smaller
than the curvature of the remaining resilient windings of the
spring 2.
[0052] The connecting section 208 of the second end winding 202 is
wound around by the connecting spring 3, so that the connecting
section 208 is within the clear inner diameter of the connecting
spring 3.
[0053] The connecting section 208, around which the connecting
spring 3 is wound or coiled, acts in combination with the
connecting spring 3 as a hinge-like connection between the spring 2
and the connecting spring 3.
[0054] As a result of the hinge action, the spring 2 has a largely
vertical compression, as the free end can rotate relative to the
connecting spring, so that this "hinge effect" also is makes an
advantageous contribution to avoiding hitching of the resilient
windings when the spring 2 is compressed.
[0055] FIGS. 3 and 4 each show a spring 2 without an adjacent
spring 2 and without a connecting spring 3.
[0056] In FIG. 3 the first end winding 201 and the V-shaped or
U-shaped passage 204, which is inclined from a horizontal plane
into the spring 2, are clearly visible.
[0057] In FIG. 4 the spring 2 is shown in a top view. The first end
winding 201 and the second end winding 202 each have alternately
the V-shaped or U-shaped passage 204 inclined from a horizontal
plane into the spring 2. The first end winding 201 and the second
end winding 202 each also have alternately the indentation 205.
[0058] Due to the indentation 205, the connecting plane of the
respective end winding 201, 202 with the respective connecting
spring 3 is arranged respectively outside the outer diameter of the
respective end winding 201, 202. This allows the end windings 201,
202 to respectively accommodate the remaining part of the spring 2
in an advantageous manner when being compressed during the
rolling-up process, when the spring 2 almost retracts to the block,
so that the mutual jamming of neighbouring springs 2 between the
spring windings moving towards each other in the vertical direction
during the compression of the spring 2 can be avoided to the
highest possible extent.
[0059] FIG. 4 clearly shows that the last resilient winding 209 of
the spring 2 is wound before the first end winding 201 in such a
way that its diameter continuously increases in a defined section
210 of the last resilient winding 209 within half a winding.
[0060] The increase in diameter for this section 210 shall
preferably be in a range from 5% to 30%, in particular from 15% to
20%, based on the diameter of the other resilient windings of the
spring 2.
[0061] Section 210 is followed by the first leg section 206 of the
indentation 205, wherein the first leg section is already on the
plane of the first end winding 201 of spring 2.
[0062] The second end winding 202 respectively also has a last
resilient winding 209 before the second end winding 202 alternately
to the first end winding, the diameter of which also continuously
increases in a defined section 210 of the last resilient winding
209 within half a winding.
[0063] The increase in diameter for this section 210 preferably
lies in a range from 5% to 30%, more preferably from 15% to 20%,
based on the diameter of the other resilient windings of the spring
2.
[0064] This allows the end windings 201, 202 to respectively take
up the remaining part of the spring 2 in an advantageous manner
when being compressed during the rolling-up process, when the
spring 2 almost retracts to the block, so that the mutual jamming
of neighbouring springs 2 between the spring windings moving
towards each other in the vertical direction during the compression
of the spring 2 can be avoided to the highest possible extent.
[0065] FIG. 5 shows a top view in a section of the first end
winding 201 of the spring 2 of the spring core 1. The section
passes through the connecting spring 3 in a plane of the largest
spring outside diameter to be measured. For the sake of clarity,
only the wire cross-sections 301 of the resilient windings in the
free end area 203 with the V-shaped or U-shaped passage 204 of the
first end winding 201 are shown of the connecting spring 3.
[0066] The free end 203 has a first section 210 extending from one
end 211 of the free end 203 to the V-shaped or U-shaped passage
204. The free end 203 also has a second section 212 extending from
the V-shaped or U-shaped passage 204 to the first end winding
201.
[0067] The connecting spring 3 has a pitch p. The length of the
first section 210 of the free end 203 has a length equal to or
greater than the pitch p of the connecting spring 3. The second
section 212 has a length of at least 2 p. Such a design of the
sections 210 and 211 with corresponding lengths enables a safe and
therefore advantageous connection of two adjacent springs 2 by a
connecting spring 3.
[0068] The V-shaped or U-shaped passage 204--formed in FIG. 5 by
way of example as a V-shaped passage 204--is arranged in the free
end 203 of the end winding 201 in such a way that there is an
offset 213 between an apex 214 of the passage 204 and a central
plane X-Y of the spring 2 in the arrangement direction of the
central axis of the connecting spring 3.
[0069] By arranging the passage 204 with the offset 213 from the
middle plane of the spring 2, an arrangement of the passage 204 is
advantageously obtained which effectively and thus advantageously
prevents the spring from hitching the resilient windings of the
spring during compression to the highest possible extent.
[0070] FIG. 6 shows a top view of the first end winding 201 with an
embodiment variant of the free end 203 of the spring 2 inserted in
spring core 1. For a better overview, only the first end winding
201 of a spring 2 is shown. In FIG. 6, the V-shaped passage 204 is
dimensioned in such a way that it is arranged between two windings
of the connecting spring 3. The two windings of the connecting
spring 3 serve as abutments for the two legs 215, 216 of the
V-shaped passage 4, thus securing the V-shaped passage 204 to the
connecting spring. The free end 203 of the first end winding of the
spring 2 is thus positioned relative to the connecting spring
3.
[0071] FIG. 7 shows an alternative design of the free end 203 of
the first end winding 201 of the spring 2. The passage 204 here is
designed as U-shaped passage 204. The U-shaped passage 204 has a
connecting section 217. The connecting section 217 is positioned at
the circumference of the outer diameter of the connecting spring 3.
The U-shaped passage 204 is dimensioned in such a way that it
spans--by way of example--two windings of the connecting spring 3.
In an alternative embodiment variant of the U-shaped passage 204,
the U-shaped passage 204 can also span less or more than two
windings of the connecting spring 1.
[0072] The two windings of the connecting spring 3 serve as
abutments of the two legs 218, 219 of the U-shaped passage 204,
thus securing the U-shaped passage 204 to the connecting spring.
The free end 203 of the first end winding of the spring 2 is thus
positioned relative to connecting spring 3.
[0073] FIGS. 8 to 13 show an alternative embodiment of the spring
2. In order to avoid repetitions, only deviations and/or additions
to the spring 2 according to FIGS. 1 to 7 will be described
below.
[0074] When manufacturing the bends in the end windings 201, 202 of
the spring 2, the problem with low springs 20 is that a relatively
low spring 20 is too low to provide enough working space for a
bending tool to produce bends in both end windings 2001, 2002
without significantly reducing the cycle time of a spring
production machine.
[0075] The spring 20 in FIG. 8 according to the alternative
embodiment therefore only shows bends in the first end winding
2001. The first end winding 2001 thus shows a free end 2003,
analogous to the first end winding 201 of the spring 2, wherein the
free end 2003 is curved. The free end 2003 also has a V-shaped or
U-shaped passage 2004 and an indentation 2005.
[0076] Essential difference to the spring 2 is that the second end
winding 2002 of the spring 20 according to the alternative
embodiment is not shaped analogously to the second end winding 202
of the spring 2.
[0077] According to this, the second end winding 2002 of the spring
20 according to the alternative embodiment shows a free end 2030.
The free end 2030 shows a curvature that is smaller than the
curvature of the remaining windings of the spring 20 according to
the alternative embodiment. The second end winding in 2002 also has
a connecting region 2031. The connecting region 2031 also shows a
curvature which is smaller than the curvature of the other windings
of the spring 20 according to the alternative embodiment.
[0078] The connection of two adjacent springs 20 to a spring core
10 is achieved by rewinding the free end 2003 with the V-shaped or
U-shaped passage 2004 of the first end winding 2001 of the one
spring 20 and the indentation 2005 of the first end winding 2001 of
the other spring 20 by a connecting spring 30. The connection is
further made by wrapping the free end 2030 of the second end
winding 2002 of the one spring 20 and the connecting region 2031 of
the second end winding 2002 of the other spring 20 by a further
connecting spring 30.
[0079] When mounting the springs 2, 20 to form a spring core 1, 10,
the springs 2, 20 are usually arranged in rows and columns.
[0080] The orientation of the springs 2, 20 can alternate in this
case so that two adjacent springs 2, 20 are connected in each case
in pairs with their free end 203, 2003 or with their indentation
205, 2005 of the first end winding 201, 2001 by a connecting spring
3. Similarly, a corresponding orientation of the springs 2, 20 is
obtained on the second end winding 202, 2002.
[0081] Alternatively or additionally, the respective last spring 2,
20 of a row or a column of the spring core 1, 10 is oriented in
such a way that it is arranged relative to the adjacent spring 2,
20 rotated by approx. 180.degree. about its vertical axis.
[0082] Such arrangements of the springs 2, 20 in the spring core 1,
10 advantageously reduce the risk of hitching of the springs 2, 20
during compression within the scope of the rolling-up of the spring
core 1, 10 for shipping.
[0083] The following method is specified for the manufacture of the
spring 2, 20 and the spring core 1, 10:
[0084] A spring steel wire is provided in a first process step.
[0085] In a second process step, the provided spring steel wire is
used to produce the resilient windings as well as the first end
winding 201, 2001 and the second end winding 202, 2002 and
respectively the last resilient winding 209 before the first end
winding 201 and the second end winding 202 with the defined section
210 of the spring 2, 20. Preferably, the winding of the resilient
windings and the first end winding 201, 2001 and the second end
winding 202, 2002 of the spring 2, 20 is carried out on a spring
winding machine.
[0086] In a subsequent method step, at least one bend, in
particular the V-shaped or U-shaped passage 204, 2004 and/or the
indentation 205, 2005, is produced in the first end winding 201,
2001 of the spring 2, 20. Preferably, the bending takes place in a
separate bending tool, which can be integrated into the spring
winding machine.
[0087] In a subsequent method step at least one bend, in particular
the V-shaped or U-shaped passage 204, 2004 and/or the indentation
205, 2005, is optionally produced in the second end winding 202,
2002 of the spring 2, 20. Preferably, the bending takes place in a
separate bending tool, which can be integrated into the spring
winding machine.
[0088] In a further method step, two respective springs 2, 20 are
connected at their respective first end winding 201, 2001 and their
respective second end winding 202, 2002 to a connecting spring 3 to
form a spring core 1, 10. The connection of the springs 2, 20 to
form a spring core 1, 10 preferably occurs on an automated assembly
system provided for this purpose.
LIST OF REFERENCE NUMERALS
[0089] 1, 10 Spring core
[0090] 2, 20 Spring
[0091] 3 Connecting spring
[0092] 201, 2001 First end winding
[0093] 202, 2002 Second end winding
[0094] 203, 2003 Free end
[0095] 204, 2004 Passage
[0096] 205, 2005 Indentation
[0097] 206 First leg section
[0098] 207 Second leg section
[0099] 208 Connecting section
[0100] 209 Last resilient winding
[0101] 210 Section
[0102] 211 End
[0103] 212 Section
[0104] 213 Offset
[0105] 214 Apex
[0106] 215 Leg
[0107] 216 Leg
[0108] 217 Connecting section
[0109] 218 Leg
[0110] 219 Leg
* * * * *