Technical Field
[0001] The present invention concerns a suspension device for supporting slats of a bedding,
in particular a suspension device with an adjustable spring characteristic.
Background for the Invention
[0002] Adjustable suspension devices for holding slats of a bedding are known from example
given
EP1649786 and
US20130334746. In
EP1649786 a suspension device is described comprising a base portion comprising slots for attachment
to a bedding structure; a top portion for receiving slats therein; and a first spring
element comprising two leaf springs extending from the base part to the top part.
A second spring element is provided on the base part of the suspension device and
extends towards, but not until the top part, whereby the second spring element is
configured as a bridge structure on the base part of the device and defines an abutment
surface facing the top part of the device. An adjustable member in the form of a notch
is provided on the top part, whereby the notch protrudes from the top part in the
direction of the abutment surface. In an non tensioned position, the notch is spaced
away from the abutment surface but upon tensioning the device, the top part is pressed
down, first only biased by the first spring element and upon contact with the abutment
surface biased by both the first and second spring elements, thereby changing the
spring characteristic. By turning the notch, the distance by which the top part can
be pressed towards the base before increasing the biasing force can be varied.
[0003] A disadvantage of a suspension device according to
EP1649786 is that the spring characteristic can only be varied by altering the distance over
which the first spring elements are to be compressed before activation of the second
spring element. As such no variation can be achieved from the first moment of compressing
the spring, nor can the strength of the variation be altered. Another disadvantage
of this suspension device is that when the notch impacts on the abutment surface,
a noise is generated which is highly unwanted in the bedding industry.
[0004] The suspension device according to
US20130334746 comprises a base portion comprising slots for attachment to a bedding structure;
a top portion for receiving slats therein; and first and second spring elements comprising
extending from the base part to the top part. The second spring element is provided
fixed to the base part of the suspension device and comprises a free end that is movably
mounted in a guide in the top part, such that upon movement of the free end of the
second spring element in the guide, the shape of the second spring element is altered
and the spring characteristic is altered.
[0005] Although the suspension device according to
US20130334746 allows varying the spring characteristic from the first compression of the suspension
device, it has the inconvenient that the free end of the second spring element tends
to move in the slot during use, thereby altering the spring characteristic unintentionally.
Another disadvantage is that when moving the free end to an extreme position as shown
in figure 33C of
US201 30334746, results in the second spring element having a major portion extending perpendicularly
in view of the base and top parts of the spring element, thereby limiting the distance
over which the suspension device can be compressed.
[0006] From the above it is clear that there remains a market need for easy to use and user
friendly suspension device allowing altering the spring characteristic over the entire
course of the suspension device and without major impact on the maximum distance over
which the suspension device can be compressed.
Summary of the Invention
[0007] The present invention meets the above market needs by providing a suspension device
for supporting a mattress comprising:
a base part comprising slots for attachment to a bedding structure;
a top part comprising slots for receiving slats therein;
a spring element provided between the base and the top part for resiliently suspending
the slats in view of the bedding structure, whereby the spring element comprises at
least:
- a first spring element extending between the base part and the top part of the device;
and
- a second spring element extending between the base part and the top part of the device;
and
- an adjustable member allowing adapting the spring characteristic of the suspension
device,
characterised in that said second spring element comprises a first spring portion
fixed to the base part and extending towards the top part; a second spring portion
fixed to the top part and extending towards the base part; and a bridge portion connecting
the free ends of the first and second spring portions, whereby the first and second
spring portions are spaced apart in a direction perpendicular to the suspension direction
and the bridge portion defining an abutment surface
and in that the adjustable member is movable in a guide or series of slots provided
in the top part and comprises an actuating member that is in contact with the abutment
surface, such that repositioning the adjustable member in said guide or series of
slots changes the contact position of the actuating member on the abutment surface,
thereby varying the spring characteristic of the device.
[0008] The second spring element is preferably fastened to the base part and to the top
part of the device preventing release of the second spring element without use of
tools or destroying the suspension device.
[0009] The first spring element preferably comprises a coil spring and more preferably two
coil springs whereby the second spring element is positioned between the first and
second coil springs of the first spring element.
[0010] It is preferred that the base part, first spring element and top part are manufactured
in a single piece and even more preferred that the base part, first spring element,
second spring element and top part are manufactured in a single piece.
[0011] The first spring element may be manufactured in a first material while the second
spring element is manufactured in a second material different than the first material.
[0012] According to a preferred embodiment the abutment surface extends in a plane parallel
to the plane wherein the series of slots or guide extends, whereby the distance D
between the top part and the contacting point of the actuating member on the abutment
surface is constant for several positions of the actuating member in the device.
Brief Description of the Figures
[0013]
Figure 1 shows perspective view of a suspension device according to the invention
Figure 2 shows a cross sectional view of the suspension device in Fig. 1 ;
Figure 3 shows a perspective view according to arrow P3 in Fig. 1;
Figures 4a, b & c show a partial side view of the suspension device in Fig. 1.
Detailed Description of a Preferred Embodiment
[0014] Figure 1 shows a suspension device according to the present invention comprising
a base part 1 comprising slots 2 for attachment to a bedding structure;
a top part 3 comprising slots 4 for receiving slats therein;
a spring element provided between the base 1 and the top part 3 for resiliently suspending
the slats in view of the bedding structure, whereby the spring element comprises at
least:
a first spring element 5 extending between the base part 1 and the top part 3 of the
device; and
a second spring element 6 extending between the base part 1 and the top part 3 of
the device; and
an adjustable member 7 allowing adapting the spring characteristic of the suspension
device.
[0015] According to the invention and as shown in more detail in Figure 2, the second spring
element 6 comprises a first spring portion 6a fixed to the base part 1 and extending
towards the top part 3; a second spring portion 6b fixed to the top part 3 and extending
towards the base part 1 and a bridge portion 6c connecting the free ends of the first
and second spring portions, whereby the first and second spring portions 6a&b are
spaced apart in a direction Y perpendicular to the suspension direction Z. The bridge
portion 6c defines an abutment surface 8.
[0016] The adjustable member 7 extends through the top part 3 and is movable in a guide
9 or series of slots provided in the top part 3 and comprises an actuating member
10 that is in contact with the abutment surface, such that repositioning the adjustable
member 7 in said guide 9 or series of slots changes the contact position of the actuating
member 7 on the abutment surface 8, thereby varying the spring characteristic of the
device.
[0017] In the represented embodiment, the first spring portion 6a consists of a U-shaped
resilient element extending -in a non tensioned state, ie when no load is applied
on the device - from the base part 1 of the device on a level Z
0 upto a level Z
1, where the first spring portion 6a extends into the bridge portion 6c. The first
spring portion is hereby oriented such that the U-shape extends in the Z-Y plane and
the bridge portion extends one of the legs of the U-shape in that Z-Y plane. The second
spring element 6b comprises two wing-like structures 11 extending from the level Z
1 to a level Z
2 where it is connected to the top part 3 of the device. The distance from Z
0 to Z
1 is smaller than the distance from Z
0 to Z
2 such that a void is defined between the free end of the first spring portion 6a that
is connected to the bridge portion 6c of the second spring element and the top part
3 of the device. The bridge portion 6c defines the abutment surface 8 that in this
case faces the top part 3 of the device and extends on a level Z
x in between the levels Z
0 and Z
2.
[0018] As illustrated in figure 3, the guide 9 or series of slots provided in the top part
3 of the device extend along the Y direction and hence make it possible to vary the
position of the adjustable member and in particular the actuating member 10 in the
Y direction. The adjustable member 7 extends in the Z direction through the guide
or slot from the level Z
2 to the level Z
x where it contacts the abutment surface 8 of the bridge portion 6c. Alternatively,
the abutment surface can be defined on a surface of the bridge portion 6c facing the
base part 1 of the device, in which case the actuating member 10 comprises a shaped
part for contacting the abutment surface 8.
[0019] The first spring element 5 in this case comprises two coil springs both extending
from the base part 1 to the top part 3 of the device, although the type of spring
to be used is not limited to coil springs but can be of any desired type such as leaf
springs, bulge springs or such.
[0020] The two springs of the first spring element 5 are preferably spaced apart in the
X-direction and are position at opposed sides of the second spring element 6.
[0021] The device is preferably manufactured in a polymeric material selected from the group
comprising: polyolefin, in particular polypropylene or polyethylene; polyester; block-copolymers
such as ABS and or admixtures thereof. Preferably the device is manufactured in one
single piece, although in order to have more options in varying the spring characteristic
of the device the first and second spring elements can be manufactured in different
materials.
[0022] Irrespective of the material choice of the device, it is preferred that the second
spring element is fixed to or unified with the remainder of the device such that it
can not be removed or separated therefrom without the use of tools or destroying the
device, the second spring element is not intended to be a easily removable part for
altering the spring characteristic.
[0023] The functioning of the suspension device according to the invention is easy and as
follows.
[0024] In assembled state, irrespective of the tension applied on the suspension device,
the actuating member 10 contacts the abutment surface, and any compression of the
suspension device due to an increase of load will be biased by the compression force
of both the first and second spring elements 5&6. As illustrated in figure 4a-c, depending
on the position of the actuating member on the bridge portion 6c of the second spring
element 6, the spring characteristic or compression force of the suspension device
can be altered.
[0025] Indeed, upon changing the contact position of the actuating member 10 on the abutment
surface 8 closer or further away from the U-shape of the first spring portion 6a of
the second spring element 6, the resistance of the second spring element to compression
is altered and as such the overall spring characteristic of the suspension is altered.
As illustrated in figures 2 and 3, changing of the contact position of the actuating
member 10 is most conveniently done by moving a grip 12 of the adjustable member 7
protruding through the guide 9 or series of slots from the top part 3 of the device.
1. A suspension device for supporting a mattress comprising:
a base part comprising slots for attachment to a bedding structure;
a top part comprising slots for receiving slats therein;
a spring element provided between the base and the top part for resiliently suspending
the slats in view of the bedding structure, whereby the spring element comprises at
least:
• a first spring element extending between the base part and the top part of the device;
and
• a second spring element extending between the base part and the top part of the
device; and
• an adjustable member allowing adapting the spring characteristic of the suspension
device,
characterised in that said second spring element comprises a first spring portion fixed to the base part
and extending towards the top part; a second spring portion fixed to the top part
and extending towards the base part; and
a bridge portion connecting the free ends of the first and second spring portions,
whereby the first and second spring portions are spaced apart in a direction perpendicular
to the suspension direction and the bridge portion defining an abutment surface
and in that the adjustable member is movable in a guide or series of slots provided in the top
part and comprises an actuating member that is in contact with the abutment surface,
such that repositioning the adjustable member in said guide or series of slots changes
the contact position of the actuating member on the abutment surface, thereby varying
the spring characteristic of the device.
2. The suspension device according to claim 1, wherein in a non tensioned state of the
suspension device a void is defined between the first spring portion of the second
spring element and the top part of the device and wherein a void is defined between
the second spring portion and the base part of the suspension device.
3. The suspension device according to claims 1 or 2, wherein the second spring element
is fastened to the base part and/or to the top part of the device preventing release
of the second spring element without use of tools or destroying the suspension device.
4. The suspension device according to any of the preceding claims, wherein the first
spring element comprises a coil spring.
5. The suspension device according to any of the preceding claims, wherein the first
spring element comprises two coil springs and wherein the second spring element is
positioned between the first and second coil springs of the first spring element.
6. The suspension device according to any of the preceding claims, wherein the base part,
first spring element and top part are manufactured in a single piece.
7. The suspension device according to claim 5, wherein the base part, first spring element,
second spring element and top part are manufactured in a single piece.
8. The suspension device according to any of the preceding claims, wherein the first
spring element is manufactured in a first material and the second spring element is
manufactured in a second material different than the first material.
9. The suspension device according to any of the preceding claims, wherein the abutment
surface substantially extends in a plane parallel to the plane wherein the series
of slots or guide extends.
10. The suspension device according to any of the preceding claims, wherein the distance
D between the top part and the contacting point of the actuating member on the abutment
surface is constant for several positions of the actuating member in the device.
11. The suspension device according to any of the preceding claims, wherein the abutment
surface 8 faces the top part 3 of the suspension device.
12. The suspension device according to any of the preceding claims, wherein the abutment
surface 8 faces the bottom part 3 of the suspension device and wherein the actuating
member comprises a hook shaped part for contacting the abutment surface.