[0001] With regard to mattress bases, a great many devices for the purpose of increasing
sleeping comfort are known.
[0002] The coil bed spring, comprising a closely woven network incorporated in a frame,
is a commonly used and comfortable spring device, but mattress bases with slats are,
on the other hand, often preferred because they give even greater comfort. The slats
are usually fixed on a frame so that they can turn individually, by means of elements
which may or may not be resilient. The possibility of each slat turning independently
of the other slats means that when one lies on them the shape of the body is followed
at the level of each slat, which results in greater lying comfort. A division into
zones with greater or smaller spring force is also possible. These advantages, together
with greater firmness, mean that many people opt for mattress bases with slats, instead
of the classic coil bed springs or box springs.
[0003] Such mattress bases with slats are constructed of a rectangular frame and a number
of slats which are placed crosswise with a certain distance between them, and which
extend from the one longitudinal member of the frame to the other, while the slats
are connected to said longitudinal members of the frame by means of elements which
fix the slats to said two longitudinal members so that they turn about their longitudinal
axis and which support them resiliently by their ends on either side.
[0004] The resilient elements with which the slats are supported influence the comfort of
the bed to a substantial degree. A bed which is not very comfortable is obtained with
a non-sprung or poorly sprung connection between the ends of the slats and the frame.
[0005] Known resilient elements for fixing mattress base slats to a frame comprise a structure
pivoting about the centre point, which elements laterally bear a slat support again
pivoting about its axis of symmetry. A disadvantage of this type of element is that
such elements mainly provide a height and direction change of the arrangement of slats,
and do less for the arrangement of their resilient properties. Another disadvantage
is that it is a complex and consequently very expensive solution.
[0006] Other known resilient elements comprise rubber bearing structures, but these have
major disadvantages. Their limited flexibility and compressibility, resulting in limited
comfort, and also their limited service life are their main disadvantages.
[0007] A known alternative to the rubber bearing structures are leaf springs. Such known
leaf springs, provided in order to connect the slat ends to the frame, are described
in NL 8402221 and NL 8400147, and are largely composed of a resilient strip which
is folded into a V-shape, and the top leaf of which is connected to a slat end, while
the bottom leaf is fixed to a longitudinal member of the frame. A disadvantage of
these known resilient elements and of mattress bases constructed with such elements
is that the fold in the leaf spring forming an acute angle is a weak point as regards
the strength and the service life of the element. Another disadvantage lies in the
fact that these resilient elements permit only a resilient movement of the slats going
up and down, and the slats cannot turn relative to their longitudinal axis, so that
lying comfort is limited.
[0008] Another known resilient element for fixing slats of mattress bases to a frame is
described in BE 905,146, and comprises a leaf spring which has a horizontal top face
and is further connected to the frame with the ends folded downwards and towards each
other, while one or more slats are fixed on the horizontal top face, with their end(s)
connected in an enclosing chamber to the resilient element.
[0009] The disadvantage of this resilient element is that we need a leaf spring - at a relatively
high cost - and must provide, on the one hand, a fixing piece for fixing the leaf
spring to the frame and, on the other, a connecting piece made of plastic between
slats and leaf spring, said connecting piece having to enclose the slat ends. Stop
blocks are also needed in order to limit the vertical compression at certain places.
[0010] The consequent disadvantage of these resilient elements, and of the mattress bases
constructed with them, lies in their cost, on the one hand, and in the necessity for
providing at least three different parts for connecting a slat along one end resiliently
to the frame.
[0011] The object of the invention is to provide a resilient element, without the above-mentioned
disadvantages, which offers the maximum comfort, on the one hand, through allowing
the slats to undergo not only the maximum vertical compression but also a certain
horizontal displacement, and in the process allowing them to turn relative to their
longitudinal axis, and which, on the other hand, is simple to fit and costs less than
the known elements with the same above-mentioned comfort-oriented properties, but
without permitting lower strength and a shorter service life of the elements.
[0012] One subject of the invention is a resilient element for fixing slats of a mattress
base to their frame, so that the slats can carry out resilient movements in the vertical
and horizontal direction and can turn about their longitudinal axis.
[0013] Another subject of the invention is a mattress base with slats constructed with such
resilient elements.
[0014] The resilient element according to the invention is characterized in that it comprises
two tubular parts lying next to each other, made up of walls running more or less
in the form of a cylindrical surface, while the axes of symmetry of the two tubular
parts lie parallel next to each other.
[0015] These identical tubular parts are connected along the top by a flat part, in such
a way that a certain distance is left between the walls of these adjacent parts lying
closest together. Both the two tubular parts and the connecting part are preferably
made of plastic, with resilient properties, and in any case of a material with similar
properties.
[0016] A flat, elongated, hollow space is provided at the top on the top face of each tubular
part, jutting out from said top face, with the lengthwise direction parallel to the
axes of symmetry of the tubular parts. This hollow space is open at the front and
back, and for the rest is enclosed by walls with rounded corners and round curves,
thus producing a more or less bar-shaped internal space which along the front and
along the back, in a direction parallel to the axes of symmetry of the tubular parts,
allows a slat with a cross-section with dimensions equal to or slightly different
from said internal space to be pushed into it, while the rounded corners and curves
in the wall mean that during the insertion elastic deformation of the wall is produced,
which leads to better gripping of the end of the slat. For this purpose, it is also
possible to provide vertical ribs in the inside of said hollow space.
[0017] Vertically below said hollow spaces for insertion of the slat ends on each tubular
part, in the lowest point of the cylindrically shaped wall of each of said two parts,
provision is also made for at least two tubes of smaller diameter than the first-mentioned
tubular parts, arranged vertically below one another, with their lengthwise direction
parallel to the axes of symmetry of the tubular parts, and provided in order to contain
a pin of corresponding diameter which at one side is driven horizontally into the
inside of a longitudinal member of the frame, while at the other side one of the tubes
is slid over the projecting part of said pin and fixed tightly thereon, to connect
the resilient element to the frame.
[0018] A mattress base with slats is obtained with the element according to the invention
by providing in a rectangular frame, along the inside of the two longitudinal members,
horizontally projecting pins directed in pairs in transverse directions at right angles
to the longitudinal members, distributed over the entire length of the frame, and
by sliding onto each pin a tube of a resilient element fitting thereon and, finally,
for every two elements lying opposite each other in a transverse direction at right
angles sliding a slat by its ends into the respective flat hollow spaces.
[0019] Further features and characteristics of the resilient element according to the invention,
and of the mattress base made with such elements, are illustrated in the description
which follows of a possible embodiment of the resilient element and a mattress base,
but without the invention being restricted to these possible embodiments.
[0020] This description is illustrated with reference to the appended figures.
[0021] Figure 1 shows a perspective drawing of a resilient element according to the invention,
in a preferred embodiment.
[0022] Figure 2 shows a front view of this resilient element according to the invention.
[0023] Figure 3 shows a righthand side view of the resilient element according to the invention.
[0024] As shown in Figures 1, 2 and 3, the resilient element according to the invention
is characterized in that it comprises two resilient tubular parts (1) and (1') which
are identical in shape and are composed of resilient walls (2) and (2') enclosing
a more or less cylindrical space. These tubular parts (1) and (1') are situated next
to each other with their axes of symmetry parallel to each other in the lengthwise
direction, in such a way that the front and rear edges of these resilient walls (2)
and (2') respectively lie in two parallel planes. The spaces enclosed by the above-mentioned
walls (2) and (2') are not shut off by transverse walls, at right angles to the axes
of symmetry in the lengthwise direction, along either of the two sides, so that the
resilient parts (1) and (1') can be described as two open tubular shapes of more or
less cylindrical shape lying parallel to each other.
[0025] The resilient element according to the invention is further characterized in that
each of the two walls (2) and (2') of the tubular parts (1) and (1') has two flattened
sides situated diametrically opposite each other - (3) and (4) for the wall (2) and
(3') and (4') for the wall (2') - the flattened sides (3) and (3') at one side and
the flattened sides (4) and (4') at the other side being situated in two parallel
planes.
[0026] The resilient element according to the invention is further characterized in that
both resilient tubular parts (1) and (1'), lying next to each other as described above,
are connected to each other by a flat, resilient connecting part (5) which is situated
in the plane in which the flattened sides (3) and (3') lie and is connected to the
edges of said flattened sides (3) and (3) lying closest to each other and opposite
each other, the dimensions of said connecting part (5) being such that, on the one
hand, the walls (2) and (2') are connected over their entire width and, on the other,
the sides of the walls (2) and (2') lying closest to each other do not come to lie
against each other, and lie far enough from each other for this not to be the case
as the result of shape changes in the two walls (2) and (2') when they are compressed
to the maximum.
[0027] The resilient element according to the invention is further characterized in that
a projecting flat box (6) and (6') is provided on each of the resilient parts (1)
and (1'), on the respective flattened sides (3) and (3') of the resilient walls (2)
and (2'), the two boxes standing on the flat sides (3) and (3') and extending with
their lengthwise direction parallel to the axes of symmetry in the lengthwise direction
of the tubular parts (1) and (1'), and having a width - at right angles to the direction
of said axes of symmetry - which is only slightly smaller than the width of the flattened
sides (3) and (3') on which they stand.
[0028] The boxes (6) and (6') extend - parallel to the above-mentioned axes of symmetry
- from the front edge of the resilient wall (2) or (2'), with such length that they
project over a substantial distance past the rear edge of the same wall (2) or (2')
running parallel to said front edge, while these projecting parts are shut off along
the bottom by base areas in the form of extensions of the flattened sides (3) and
(3'), situated in the same plane.
[0029] The walls (7) and (7') of the two boxes (6) and (6') are made of material with resilient
properties, preferably plastic, and are of such a shape that they enclose a flat,
elongated hollow space (8) and (8'), while the transverse-lying front sides and rear
sides are not shut off, so that the flat hollow spaces (8) and (8') are accessible
in the lengthwise direction of the boxes (6) and (6') along both sides.
[0030] The resilient element according to the invention is further characterized in that
the wall (7) and (7') of the boxes (6) and (6') runs from the top of the flattened
sides (3) and (3') with two wall parts (9) and (10) at right angles thereto on the
flattened side (3), and (9') and (10') on the flattened side (3'), parallel to each
other, while higher up they pass into horizontal parts (11) and (12) and (11') and
(12') respectively with rounded corners, and then after a symmetrical widening of
the hollow spaces (8) and (8') go back into vertically running wall parts (13) and
14) and (13') and (14') respectively, with rounded corners. These vertical wall parts
(13), (13') and (14), (14') are then connected at the same height to a horizontal
top wall (15), (15'), going back into it with a rounded corner. On the horizontal
top walls (15) and (15'), passing into the corners which form the transition with
the vertical wall parts (13), (13') and (14), (14'), and in the centre of the top
walls (15) and (15'), in the lengthwise direction, provision is also made over the
entire length for semi-cylindrical curves (16) and (16') projecting higher.
[0031] On the bottom side of the spaces (8) and (8') which are enclosed by the walls (7)
and (7'), and which are formed by the flattened sides (3) and (3') of the walls (2)
and (2') there are in each case two vertical ribs (17) and two vertical ribs (17')
respectively which extend in the lengthwise direction over the length of the boxes
(6) and (6'), and are disposed in such a way that the bottom side of the enclosed
spaces (8) and (8') are divided symmetrically by them into more or less equal parts,
while the height of said ribs corresponds to the height of the vertical wall parts
(9) and (10) and (9') and (10') respectively.
[0032] The resilient element according to the invention is also characterized in that a
tube (18), (18') is incorporated in the other flattened sides (4) and (4') on the
walls (2) and (2'), diametrically opposite the boxes (6) and (6'). This tube (18)
or (18') extends in the direction in which the axes of symmetry lie, in the lengthwise
direction of the tubular parts (1) and (1'), with the same length as said parts, and
incorporated parallel thereto in the flattened side (4), (4'), so that an equal part
of the tube wall of this tube (18), (18') projects into the spaces enclosed by the
tubular parts (1) and (1'), and an equal part of said tubular wall projects from said
tube wall along the outside edge of the flattened sides (4) and (4'). The diameters
of the tubes (18) and (18') are such in this case that the tubes lie fully inside
the flattened sides (4) and (4').
[0033] The resilient element according to the invention is also characterized in that another
identical tube (19), (19') respectively, having the same length, is fixed against
each of these tubes (18) and (18'), both the tubes (18) and (19) and the tubes (18')
and (19') being connected to each other other over their entire length through walls
merging into each other, in such a way that they lie with their axes of symmetry in
the lengthwise direction in a plane which is at right angles to the plane in which
the flattened sides (3) and (3') or (4) and (4') are situated. Both the tubes (18)
and (19) and (18') and (19') are provided on the inside with projecting ribs (20)
and (21) and (20') and (21') respectively, standing at right angles to the wall and
situated diametrically opposite each other.
[0034] A mattress base, in a preferred embodiment according to the invention, and designed
making use of resilient elements according to the invention, in the embodiment described
above comprises a rectangular frame, characterized in that horizontally projecting
cylindrical pins are placed in the innermost side of the two frame sides running in
the lengthwise direction, said pins being distributed at regular intervals along the
entire length of said longitudinal members, and being placed in such a way that each
pin in one longitudinal member can be connected to a pin in the other longitudinal
member along a transverse connecting line at right angles to the two transverse members.
The distance between said pins of the same longitudinal members must be such that
the interval between the axes of symmetry of each pair of successive pins corresponds
to the vertical spacing between the axes of symmetry of the boxes (18) and (18') (or
between (19) and (19')).
[0035] The mattress base according to the invention is further characterized in that a resilient
element according to the invention is placed on each pair of adjacent pins on the
same longitudinal member by sliding the tube (18') (or (19')) on one pin and sliding
the tube (18) (or (19)) on the other pin, the dimensions of the pins and of the tubes
corresponding in such a way that each resilient element is secured under tension on
two pins. The resilient elements are thus fixed with the axes of symmetry in the lengthwise
direction of the tubular parts (1) and (1') horizontally and at right angles to the
direction of the longitudinal members of the frame, and for the elements on different
longitudinal members situated in pairs in line with each other, and with the part
of the boxes (6) and (6') past the rear edge of the walls (2) and (2') facing each
other.
[0036] The ends of a slat are pushed into each pair of boxes (6) and (6') lying in line
with each other, and belonging to two resilient elements which are fixed on a different
longitudinal member. The cross-sections of the slat ends, which are more or less rectangular,
and of the free spaces (8) and (8') correspond to such an extent that the slats are
secured therein under tension, while the walls (7) and (7') through their elasticity,
and through their curves (16) and (16') lying in the lengthwise direction, permit
a slight enlargement of the free spaces (8) and (8') when the slat ends are being
pushed into them, so that once they are in there the slats can be clamped even better.
The ribs (17) and (17') in the hollow spaces (8), (8'), which press against the bottom
surface of the slat ends in this case ensure an even greater resistance against sliding
of the slat ends out of the spaces (8) and (8').
[0037] The mattress base with slats according to the invention is further characterized
in that each resilient part (1) or (1') of the resilient elements can be fixed as
desired at two different heights, either by sliding the tube (18), (18') or the tube
(19), (19') on the pin provided.
[0038] The resilient elements according to the invention in a preferred embodiment are made
in one piece, of plastic, with durable and elastic properties.
[0039] An advantage of the invention is that we have a resilient element which is simple,
and thus cheap, to manufacture, without the use of leaf springs, with which a mattress
base which permits a separate movement of each slat (turning of the slats about their
longitudinal axis, and movable so that they spring vertically and horizontally) can
be constructed, so that ideal comfort is achieved, due to the fact that the shape
of the body is followed at every point through the direction of the rotatable slat
lying underneath, while the compression takes place according to the local weight,
both in the horizontal and in the vertical direction.
[0040] Another advantage of the invention is that, in order to increase comfort, each slat
is adjustable as desired to two different heights, so that lower and higher up zones
can be obtained in the mattress bases, in order to obtain a lying surface which is
better adapted to the body.
[0041] Of course, the shape of the resilient elements is not limited to the preferred embodiment
(with appended figures) described here, but other fixing devices, for example, could
be provided for fixing the slats to the resilient elements, and/or for the resilient
elements to the frame, and the shape as a whole can differ from the shape proposed
here.
1. Resilient element, for fixing the slats of a mattress base to the frame thereof, said
element allowing both vertical and horizontal movements of the slat(s) fixed to it,
and also a rotation of each slat individually about its longitudinal axis, characterized in that the element comprises two identical tubular parts (1) and (1') - with elastically
deformable walls (2) and (2') - which lie next to each other with their axes of symmetry
in the lengthwise direction parallel to each other with sufficient space between them
for one not to obstruct the deformation of the other, and connected to each other
by an elastically deformable connecting part (5), while the walls (2) and (2') are
each provided with a device (6) and (6') for fixing the end of a slat, which device
extends parallel to the axes of symmetry in the lengthwise direction of the tubular
parts (1) and (1'), with the top sides of the two slats lying in line with each other,
and each element also being provided with at least one device for fixing it immovably
to a frame side, in such a way that each slat connected to it lies horizontally.
2. Resilient element according to Claim 1, characterized in that each fixing device for fixing to a frame side is made multiple, or is adjustable
in such a way that more than one fixing height is possible.
3. Resilient element according to any of the preceding claims, characterized in that the tubular parts (1) and (1') are in the form of a cylindrical surface, and are
each flattened along two sides lying diametrically opposite each other, so that for
each tubular part two parallel flat sides (3), (4) and (3'), (4') are formed, lying
in pairs - (3), (3') and (4), (4') - next to each other in two parallel planes, while
the connecting part (5) is in the form of a flat part of low thickness, and connects
the tubular parts (1) and (1') over the full width of the walls (2) and (2'), lying
in the same plane as two of the flattened sides (3) and (3').
4. Resilient element according to one or more of the preceding claims, characterized in that the devices for fixing the slats, running from the top of the flattened sides (3)
and (3') lying in line with each other, are in the form of flat, hollow, elongated
boxes (6) and (6'), extending with their lengthwise direction parallel to the axes
of symmetry of the tubular parts (1) and (1'), and running through from the front
edge of the walls (2) and (2') until they are past the rear edge, while the base area
of these projecting parts is formed by lateral extensions of the flattened sides (3)
and (3'), lying in the same plane, while these boxes enclose elongated spaces (8)
and (8') which are accessible in their lengthwise direction along both sides through
the open transverse sides.
5. Resilient element according to Claim 4, characterized in that the walls (7) and (7') of the boxes (6) and (6') are elastically deformable and are
made up of flat parts, each enclosing a bar-shaped space (8) and (8'), with a symmetrical
narrower bar-shaped part lying against the tubular parts (1) and (1') over the entire
length of the boxes (6) and (6'), while provision is made in the top walls (15) and
(15') for semi-cylindrical curves (16) and (16') which project upwards, and there
is at least one raised rib (17) on the bottom sides of the enclosed spaces (8) and
(8'), parallel to the side walls of the boxes (6) and (6'), over the entire length
thereof, and not going higher than the narrower bar-shaped part.
6. Resilient element according to one or more of the preceding claims, characterized in that each tubular part (1) and (1') in its respective flat side (4) and (4') - diametrically
opposite the fixing devices for the slats - is provided with a tube (18) and (18')
which is incorporated centrally parallel to the axes of symmetry in the lengthwise
direction of the tubular parts (1) and (1') over the entire length thereof in the
flat sides (4) and (4'), so that the tube wall of the tubes (18) and (18') projects
as much above as below the walls (2) and (2').
7. Resilient element according to Claim 6, characterized in that each tubular part (1) and (1') also has provided for it at least one tube (19) and
(19'), which are identical to the tubes (18) and (18'), and which are connected to
the tubes (18) and (18') parallel to them and over the entire length thereof by walls
merging into each other, so that for each tubular part (1) and (1') at least two contacting
tubes (18), (19) and (18'), (19') are provided, said tubes being situated with their
axes of symmetry in the lengthwise direction in a plane which is at right angles to
the flattened sides (4) and (4') of the walls (2) and (2').
8. Resilient element according to Claims 6 and 7, characterized in that all tubes (18), (19) and (18'), (19') which are provided on a frame side as a fixing
device for the resilient element have internally projecting ribs (20), (21) and (20'),
(21') which project radially from the inside of the wall, lying diametrically opposite
each other.
9. Mattress base provided with resilient elements according to one or more of the preceding
claims, characterized in that they are fixed against the inside of the two longitudinal members of a rectangular
frame, at regular intervals from each other over the entire length of said longitudinal
members, and are placed in such a way that they lie in pairs in a transverse direction
perpendicular to the frame longitudinal members, and for each pair of resilient elements
thus situated two mattress base slats are fixed on the tubular parts (1) and (1')
of the respective elements lying in line with each other, and the frame is thus provided
with slats which are placed transversely at regular intervals, and which are supported
in their ends by the resilient elements so that they spring horizontally and vertically
and turn about their longitudinal axis.
10. Mattress base according to Claim 9, provided with resilient elements according to
one or more of Claims 6 to 8, characterized in that the resilient elements are fixed to the longitudinal members of the frame by pins
which project horizontally from said longitudinal members, and each sit clamped in
a tube (18), (18') and (19), (19') belonging to a different tubular part (1) and (1'),
so that each resilient element is fixed on two pins, with its boxes (6) and (6') lying
horizontally, and with the side projecting past the edge of the walls (2) and (2')
facing the centre of the frame, while it is possible through the choice of the tubes
- (18) or (19), (18') or (19') - to have different fixing heights for each tubular
part (1) and (1') of a resilient element.
11. Mattress base according to one or more of Claims 9 and 10, provided with resilient
elements according to one or more of Claims 4 to 8, characterized in that the two ends of each mattress base slat sit fast in two boxes (6) and (6') belonging
to two resilient elements which lie in line with each other in a transverse direction
perpendicular to the frame.