Note: Descriptions are shown in the official language in which they were submitted.
WO 91/OS496 . PCr/DK90/00264
Extension Table
The present invention relates to an extension table
with two table top sections arranged mutually slidably,
~he sections being supported by side aprons, which are
slidably mounted to a mounting frame and are mutually
connected by a link mechanism, which can be activated by
swivelling about a vertical axis for synchronous move-
ment of the table top isiections away from and towards
each other; and one in a storage position under the
table ~op placed extension leaf having a length, which
corresponds to the width of the table, and the extension
lea~ is in that position lengthwise at least approxi-
mately at a right angle to the intersecting edges of the
table top sections, and arranged such that the extension
leaf can be swivelled about a central axis in the mount-
ing frame, so that the side edges of the extension leaf
become parallel to the abutted edges of the table top
sections and can be elevated to levelling with the table
top when ~he table top sections are in their remotest
position and can be closed upon the extension leaf to
form an extended continuous table top.
~ ables of this type are particularly known from the
US-patents Nos. 1,915,346 and 1,915,437 and 2,007,475 as
well a~ 3,294,042, where the closest known technique is
considered to appear from the US-patent 2,007,475. For
all four designs apply that several manual movements are
~equired in order to extend the table and to stow the
leaf away again. Standing at the end of the table it is
initially reguired to pull the two table top sections
away from each other, whereafter it is nec~ssary to move
to a position straight in front of the centre of the
table to turn the extension leaf into position. Raising
takes place in all circumstances by means of cooperating
wedges. ~aising can take place be~ore the turning as at
the construction dealt with in the US-patent 1,915,3~6
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WO 91/0~496 PCr/DK90/00264
or after the turning has been completed. However, in all
circumstances a fair amount of muscular strength is
rec~uired, especially just at the peak where the movement
may simultaneously release a heavy vibration in the
construction. At the construction dealt with in the
US-patent 3,294,042 the extension leaf is elevated by a
strong spiral spring being released at: the turning and
pushing the extension leaf upwards to levelling with the
table top. At return the extension leaf shall be pushed
downwards against the spring force ancl ~e held downwards
at the same time as the leaf be turnecl. When the exten-
sion leaf is at level, one needs to walk ~rom the centre
to behind the end of the table to slicle the table top
sections together around the extension leaf. The designs
are also more or less dedicated exactly to the specific
type o~ table dealt with in the respective patent speci-
fications, thus the construction dealt with in the
US-patent 3,294,042 may only with difficulty be prac-
ticed at other ta~les than tables havin~ a leg at each
corner.
From US-patent ~,494,466 a table i5 known having
three wedge surfaces arranged in a circle and where the
extension leaf at the under side is equipped wi~h driv-
ing wheels for rolling on the wedge sur~aces. Swivelling
of the extension leaf from the storage position takes
place by a vertical edge of the wedge surfaces pushing
at the wheels and the levelling takes place by the wedge
surfaces being turned down under the wheels. The con-
struction has the disadvantaga that lo~wering and level-
ling of the leaf is difficult to control as the weight
of the leaf contributes to or acts against the rotation
when the wheels act on the wedge surfaces. The wedge
elements also result in a relatively large construction ;;
height.
The purpose of the invention is t~ indicate an
extension table of the type mentioned in the preamble,
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WO91/05~96 PCT/DK9D/002
where extension of the table top and storage of the
extension leaf can be achieved in a sole operation, and
that the csnstruction is ~qually usable regardless o~
the shape of the table top, that is to say whether the
two table top sections are quadratic, rectangular, round
or oval and the support construction, that is to say
whether there is a table leg at each corner, a support
at each end or a column at the centre. This is obtained
according to the invention in a table having the subse-
quent chara~-teristic features, namely that it comprises
a cam disc and a drive unit with operating device for
rotating the cam disc about its axis and to which the
link mechanism is conn,ected, and that the extension leaf
at the under side has a driving stud for engaging the
cam disc such that the extension leaf rotates from the
storage position to the elevating position by rotation
of the cam disc as the top sections are pulled outward-
ly, and that an elevating device is connected to the cam
disc in such a manner that it abuts the under side of
the extension leaf for elevating the extension leaf to
the final position level with ~he table top, and by
fur~her rotation of the cam disc the table top sections
are closed upon the extension leaf.
At this improvement the mechanical construction can
be made as a separate compact unity, whereon the table
top sec~ions and the extension leaf with almost optional
shape can be assembled, just as the choice of the leg
construction is free. The mechanical construction can be
made as a flat rectangular box only taking up negligible
space in the height and does not become visible for a
standing person or one who sits in the proximity of the
table, just as it does not hamper those sitting at the
table. The table can be extended by the extension leaf
by activating the operating lever, whereby the movements
take place in consistent order until the extension lea~
is brought to its extended position. Storage also occurs
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WO91/05496 PCT/DK90/00264
automatically by activ~ting the operating lever. Turning
of the cam disc can be undertaken in different ways,
e.g. by a cable around the disc in a groove, a
rack~-and-pinion or by a small electrical motor, which
pulls at the periphery of the cam disc or at the rota-
tional axis and is operated by finger-touch at the edgP
of the table.
In order to allow swivelling of the extension leaf
the table top sections cannot be attached to the aprons
in the xegion of the edges facing each other and the
swivelling direction of the extension leaf, whereby one
corner of the table top sections is not stably sup-
ported. This can be met with dowels and corresponding
receiving holes in the facing edges of the sections and
the leaf. An extra support can be obtained pursuant to
the invention by placing at least one wedge element at
. the under side of the extension leaf and a wedge element
at the upper side of the cam disc and positioned in
relation to each other such that the extension leaf is
elevated to firm abutment against the under side of the
two table top sections in the starting position. The
table top sections are in this way ef~iciently supported
and at the same time the extension leaf is in a locking
position. It is thus avoided that the extension l~af can
be set in vibrations in the storage position, generating
a-"fluttering" as a consequence of movements in the
table. The wedges are, however, placed such that the
extension leaf is lowered before initiation of the other
movements such that the upper side of the leaf is not
scratched against the under side of the table top sec-
tions.
In order to reduce the power for operating the
table it is preferred to almost balance the weight of
the extension leaf, but however, not more than the re-
maining resultant weight is adequate to letting the leaf
by its own weight go back to its lowermost position. The
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WO91/05496 PCT/DK90/00264
~alancing can pr~ferably be made such that the rotation
axis of the extension leaf supports a spring leaf which
can lie in a profile under the table .in its longitudinal
direction.
The levelling device, which leve:ls the extension
leaf at level with the tablP top, can be designed in
different ways, for instance it can be a ~winging link
suspension at the inner side of the mounting frame as
indicated in the claims and exemplified in the follow-
ing. The construction is simple and oc:cupies only a
small space, but there could also be u.sed eccentrics,
wedges or the levelling could be made on the rotation
axis of the ext nsion leaf by an elect.rical linear
motor.
.. The invention shall be described closer in the
- following with re~erence to the accompanying drawing,
which shows:-
Figs..l and la to Figs. 7 and 7a, conjugated sche-
matic functional figures, which illust,rate the function
of the table accordi~g ~o the inventian, where the table
is seen from the side and from above, respectively~
~-, , , . Fig. 8 one end of the mechanical construction seen
from above,
Fig. 9 the mechanical construction seen from above
as in Fig. 8, but without sleighs whic'h carry the table
"top sections and where the starting position of the rod
connection (Fig. l) is suggested by A, and the maximum
pull-out position ~Fig. 6) is suggeste~ by B, and the
closed position about the extension leaf (Fig. 7) is
suggested by C r
Fig. 10 an enlarged cross section of the bearer of
the frame and the apron,
Fig. 11 a cross section o~ the cam disc construc-
tion, and where the extension leaf is elevated at the
table top level,
Fig. 12 one end of the swinging link suspension to
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WO9l/0~496 PCT/DK9~/00264
raise and lower the extension leaf seen from the side,
where the elevated position is indicated by dashed
lineS t
Fig. 13 a cross section of the construction shown
in Fig. 12, and
Fig. 14 a longitudinal cross sec~ion of the pivot
arm down under the cam disc and towards the extension
leaf in the starting position.
In connection with the schematic functional figures
shown in the drawings Figs. l,la to 7,7a, in the follow-
ing a brief functional description shall be given of the
table at its extension by an extension leaf, as the main
parts of the table shall be indicated by way of intro-
duction. The table includes a table top comprising two
table top sections 2a, 2b, an extension leaf 4, a sup-
port structure 6 with legs and a mechanical construction
8, whereon the other main parts are mounted.
In the starting position of the table, that i5 to
say the ciosed position of the table, the two table top
sections are completely pushed together, and the exten-
sion leaf is in its storage position under the table top
with the upper side in firm engagement against the under
side of the table top. The extension leaf, which has a
length corresponding to the width of the table top, lies
in the longitudinal direction of the table in the
storage position, see Figs. 1 and la.
The slot at the side side is covered by cover
plates or a curtain of vertical strips such that the
slot is concealed, preventing a hand or fingers acci-
dentally getting caught. However, at swivelling o~ the
extension leaf the cover plates or curtain slide away.
When the table is to be extended by the extension
leaf, an operating handle 10 is pulled at the table end,
releasing a subsequent number of movements of the exten-
sion leaf and the two table top sections, until the
table is extended.
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WO91/05496 PCT/DK90/002
The movements are initiated by lowering ths exten-
sion leaf 4 a short distance, such that it is clear of
the under side of the table top, see Figs. 2 and 2a.
As it appears from Figs. 3 and 3a hereafter a syn-
chronous sliding occurs of the two table top sections
2a, 2b away from each other.
Immediately upon this ~he extension leaf 4 ini-
tiates a 45 rotation about a vertical axis in the
c ntre of the table, see Figs. 4 and 4a.
The rotation movement is ended when the extension
leaf is turned such that it stands transversely to the
kable; at the same time the two table top sections are
pushed so ~ar apart corresponding to the width of the
extension leaf, see Figs. 5 and 5a.
Upon the extension leaf being turned in position
transversely to the table it is raised to level with the
table top at the same time as the two table top sections
are displaced an additional short distance away from
each othex, see Figs. 6 and 6a.
In the last movement the two table top sections are
pulled together against the extension leaf, and the
table top is now extended by the extension leaf, see
Figs. 7 and 7a.
When the table shall bee shortened the movements
occur in reverse sequence, khat is to say the two table
~t~p sections are pushed a short distance from each
other, whereafter the extension leaf is lowered and the
table top sections are pulled a short distance towards
each otherO When the extension leaf is ~urned in the
longitudinal direction of the table the table top sec-
tions are pulled completely together. In the last move-
ment the extension leaf is wedged up against the under
side of table top.
The mechanical construction 8, whereon the main
parts of the table are assembled, and which procure the
movements of the leaves 2a, 2b, 4 is created as a flat
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WO91/05496 PCT/DK90/00264
rectangular construction about a welded mounting frame
12 of steel profiles and having side beams 14a, 14b of
rectangular steel profiles and two end elements 16 of
bent sheet material.
The two tablP top sections 2a, 2b are assembled on
a sleigh each (see Figs~ 8 and 10 ) consisting of two
side aprons 18a, 18b in the shape of rectangular steel
profiles, which are slidably guided on rollers 20a, 20b
on the outer side of the side beams l~La, 14b of the
mounting frame. At heavy loads as occurring with marble
table tops a construction can be used instead where the
side beams have an outwardly open C-shaped cross-section
- and where the side beams of the sledge has driving
wheels, e~g. wheels of nylon, which can roll inside the
~-section. ~hereby bigger wheels can be used resulting
in a lighter surface pressure. It appears, in fact, that
by small wheels and heavy surface pressure the material
of the pro~iles can be brought to the apparent limit of
elasticity. Thereby wheel prints in the rails are
caused, resulting in an inferior running, and at the
same time there is a risk of abrasion of the track re-
sulting from askew running in the rails. At the end of
the sleigh the side beams are connected to a cross bar.
At the two outermost corners of the sleigh there are at
a distance in a plane above the frame with distance
_elements fixed mountings 22a, 22b in the shape of hori-
zontal leaf pieces, whereon a table top section is
plaeed and mounted by screws from the under side. The
height of the distance elements are adjusted such that
the extension leaf can be contained between the under
side of the table top and th~ upper side of the moun~ing
frame/side aprons. For adjusting the table top sections
and the leaf the cross member 30 mentioned in the fol-
lowing can be made of a U-profile with the opening up-
wards and wherein is put a loose second U-profile with
the bac~ turning upwards. At each side of the first
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WO91/05~96 PCT/DK90/00264
U-profile is mounted an adjusting screw for raising or
lowering the second U-profile and thereby the edge of
the leaf or top sections. If the angularity is out of
line it can be realigned by adjustment at one of the
sides.
The synchronous movement of the two table top sec-
tions (see Figs. 8 and 9) is generated by an almost
circular cam disc 24 and two three-link rod connections
26, each of which is linked to the two table top sec-
tions ~a, 2b and to the cam disc, which is rotatably
embedded about a vertical axis in a bridge 28 in the
sha~e of a piece o~ flat steel mounted transversely at
the centre of the mounting ~rame. The three-linked rod
connection comprises three pieces of flat steel linked
together, where the ~irst 26a by its free end is con-
nected to the cam disc at its periphery. The other end
of the rod is connected to the second rod 26b approxi-
mately at the centre thereof. One end of this rod is
connected to the mounti~g frame of a cross bar 30. The
other end is connected to the end of the last link rod
26c, the other end of which is connected to a cross bar
32 at the sleigh. The first rod of the ~ink connections
has a bend, so they can be connected diametrically oppo-
site on the cam disc and in order that they are clear of
a central axis 34 to the extension lea~. In the starting
~pQsition, whera the two table top sections are drawn
closely together, the connection point af the link con-
nections to the cam disc is positioned opposite ~he
corresponding table top section and at the longitudinal
centra line of the table.
Rotation of the cam disc will cause the sleigh to
displace in the longitudinal direction of thP table
through the interchange in the link connection. At the
initial rctation of the cam disc a dislocation of the
table top sections will not occur. This short standstill
passes to a minimal dislocation of the sections and
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WO91/05496 PCT/DK90/002
further into an accelerated and subsequently lessening
elapse, when the cam disc is turned 180 and the con-
nection of the link connection to the cam disc is turned
about at the opposite side in the longitudinal direckion
of the table. This corresponds to the table top sections
being in their maximum extracted position cf. Fig. 6,
that is to say where the distance between the table top
sec~ions 2a, 2b are larger than the width of the exten-
sion leaf.
For stabilizing the edges of the leaves compared to
each other the edges of the table top sections are pro-
vided with outwardly projecting dowels 36, see Fig. ~2,
which are staggered to each other and intended for en-
gagement with corresponding holes at the opposite edge.
The extension leaf is provided with corresponding holes
as in the edges of the two table top sections. The extra
distance, which the two table top sections is retracted
from each other in relation to the width of the exten-
sion leaf, is in order to allow space for thesa outward-
ly projecting dowels and such that they do not scratch
against the edges.
When the cam disc is oversteered, that is to say is
turned an additional short distance, ~he table top sec-
tions are closed upon the extension leaf 4 and the
dowels 36, which are bevelled, are caught in the cor-
responding holes in the extension leal`. At storage o~
the extension leaf the cam disc is turned in the oppo-
site direction, whereby the table to~ sections are
pushed from each other, until the connection point of
the link connection lies in the longit:udinal centre line
of the table in order that the dowels are clear o~ the
extension leaf.
The construction of the cam disc (see ~igs. 9 and
11) comprises two parallel disc elements 38a, 38b, which
in the centre are assembled about a plastic hub 40 ~m-
bedded about a hollow, vertical shaft bushing 42 welded
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wo9l/os4s6 PCT/DK90/OOZ64
to the centre of the bridge 28 of the mounting frame,
which consist of a rectangular steel profile. In order
to make the cam disc run as easily as possible, the cam
disc slides on a plastic washer 44 embedded about the
shaft bushing. The extension lea~ 4 is caxried by a
central stud 34 placed in the shaft bushing of the cam
disc and at the top provided with a mounting 48, which
is em~edded in a groove at the under side of the exten-
sion leaf and fixed by screws. Between and to the cross
bar of the mounting frame and the bridge a rectangular
steel profile 50 is mounted underneath in the longitu-
dinal centre line of the table, wherein ther2 is placed
a longitudinal, upwards curved leaf 52 to almost balanc-
ing the weight of the extension leaf, as the rotation
axis of the extension leaf is supported on the peak of
the spring leaf through a hole in the longitudinal pro-
file. When the extension leaf is elevated and lowered,
the stud slides freely in the bushing, but is, however,
hindered from tearing up by a locking ring embedded in a
groove in the lower end of the stud, which acts against
the edge of the bushing.
. Another and better construction for balancing the
weight of the extension leaf proves to be a construction
comprising a spring-loaded eccentric embedded at a cross
axis in the profile 50, such tha~ one end, the long end
ca~ries the stud and the other end connected to a hori-
zontal helical spring, the other end of which is con-
nected to an adjusting screw at the end of the profile
50. By tightening or loosening of the screw the spring-
load can be adjusted to the weight of the actual exten-
sion leaf. The construction offers the advantage of
acting during the entire vertical movement o~ the leaf,
in contrast to the spring leaf mainly acting in the
lower position of the leaf.
The initial lowering of the extension leaf at ex-
tension of the table top (~entioned in connection with
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4s6 PCT/DK90/002
Fig. 2) and the terminating wedging against the under
side of the table top when the leaf is brought in
storage position is made by two wedge elements 54a, 54b
of plastic (Figs. 11 and 9). One wedge element 54 is
mounted at the upper side of the cam disc, and the other
element 54b at the leaf mounting. In the starting posi-
tion ~he wedge S4b of the extension leaf rides on the
wedge 54a of the cam disc such that the extension leaf
is urged up to firm abutment against the under side of
the table top. At the initial movement, that is to say
rotation of the cam disc, its wedge element is turned
away under the wedge element of the extension leaf,
whereby the leaf is lowered a short distance, the equi-
valent of the height of the wedge element, and it is
clear of the table top. The wed~e elements have a short
length such that only by a short rotation o~ the cam
disc they become clear of each other, and it occurs
be~ore movement of the two table top sections and swi-
velling of the extension leaf, so the upper side of the
leaf is not scratched. During the following movements
the wedge elements get clear of each other. At termina-
tion of the storage of the extension leaf the wedge of
the cam disc is turned down under the wedge of the ax-
tension leaf thereby elevating the leaf to firm abutment
against the under side of the table top. It occurs upon
completion o~ the other movements of the leaves. The two
table top sections are only f ixed at their auter ends,
namely at the mountings of the sleighs, and stretch
hanging freely towards each other. In the starting posi-
tion the intersecting edges are however locked in rela-
tion to each other by dowels as mentioned earlier but
this is a loose fixation, which does not hinder movPment
of the two leaves in the vertical direction; There~ore
the wedging of the extension leaf against the table top
gi~es an essential contribution to stability of the
table top sections, and at the same time hinders a
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WO91/05496 PCT/DK90/002
"flapping" movement ~f the extension ].eaf in the storage
position which can be caused by the vibrations, which
appear when using the table and floor tremors caused by
traffic around the table.
For turning o~ the extension leaf this is at the
under side provided with a driving pin 56 in the shape
of ~n angled piece of steel rod, where one leg is em-
bedded in a trac~ at the undQr side of the leaf 4 and
latc~ed with a plate 58 screwed to the under side by
screws, and where the other leg, which is the driving
pin, ~rojects through a hole in the leaf perpendicularly
to the table top. At a level just above the cam disc
~here is a curve 60 in the shape of a plate welded to
the mounting frame. The curve has a track, which runs
along the periphery of the cam disc and stretches a
- quadrant from a starting position 62a for the driving
pin of the extension leaf, where the leaf is turned in
; the longitudinal direction of the tabl~e, and a delivery
position 62b, where the leaf is turned in a transverse
direction of the tableO At extension oE the ta~le the
driving pin sits in the short track in the starting
position 62a and stretches downwards a;long the periphery
of the cam disc. During the initial rotation movement of
O the cam disc nothing occurs, until a notch 64 in the cam
disc is opposite the driving pin, grips this and leads
~i~ along the curve, whereby the extension leaf swivels
until the pin is caught in the delivery track 62b, cor-
responding to the extension leaf being t~rned in a
transversely position of the table. Due~ to tolerances of
the construction and the inertia of the~ leaf in the
swivelling movement the leaf has a tendency to turn too
far, especially where very heavy exten~;ion leaves such
as marble are concerned. To prevent th.is ovarswivelling
the leaf at its under side is provided with a depending
stop which acts ~gainst the side beams. Further rotation
o~ the cam disc can occur unimpeded, as the driving pin
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WO 91~05496 PCl /DK90/00264
14
is led outside the circumf erence of the cam disc . When
the extension leaf shall be returned to the storage
position the driving pin is again caught in khe notch of
the cam disc and is returned for deli~ery in the start-
ing position. The length of the driving pin is adapted,
such that it does not slide up its track, when the ex-
tension lea~ is elevated at level with the table top.
For elevating the extension leaf 4 Ssee Figs.
12,13,8 ) at level with the table top, when thP exten-
sion leaf is turned transversely to the table, at the
inner side of the side beams 14a, 14b of the mounting
frame there is a rod parallelogram, which is activated
by the cam disc by a triangular pivot arm 66. The rod
parallelograms are identical at each side and include
four knee-joints 68a, 68b, each consisting of two small
sheet materials, which by one end are hinged together.
The other end, the lowermost, is pivoted to the mounting
frame. The other end of the topmost sheet is pivoted to
a horizontal longitudinal rod 70 parallel to the side
beam and having a length at least approximately cor-
responding to.the width of the extension leaf, and
whereon the leaf is elevated and supported. The folding
points of the knee-joints are interconnected by a
through rod 72, which by a pull rod 74 in the shape of a
piece of round bar steel is connected to the pivot arm,
as.the end of the pull rod is angled and catch into the
connection rod, likewise the other end of the pull rod
is angled and catch into a hole in an upstanding flange
76 of the pivot arm. As mentioned the pivot arm consists
of an approximately isosceles triangular sheet material,
which is pivotally mounted at a trestle 78 of bent steel
plate, which in turn is welded to the upper side of the
longitudinal profile 50, which contains the leaf spring.
Thus the pivot arm can pivot about a point in the longi-
tudinal centre line of the table. The top of the pulling
arm, which stretches down under the cam disc, is stag
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wosa~o5496 PCT/DK90iO02
gered in a plane closely against the under side of the
disc and is provided with a lonyitudinal mesh notch 80
(see Fig. 8). At the undeir side of the cam disc there is
a driver 82 in the shape of the end of a through pin in
the disc, and which is hindered from being pulled up by
a locXing ring at the under side of the disc. The driver
is placed so far along the cam disc that it intermeshes
with the notch in the pull arm 66 and is placed such in
relation to the notch of the cam disc, which intermeshes
with the pin 56 of the leaf 4 for swivelling of the
leaf, that it is turned in position before the driving
pin activates the pull arm 66 to swivel. Thereby there
will occur a draw in the pull arm and the rod which
interconnects the knee-joints. At the dislocation of the
pull arm the knee-joints will rise, abut the under side
of the extension leaf, which thereby is levelled at
level with the table top. The knee-joints 6Pia, 68b are
brought exactly over the folding point, such that they
stand in locked position and form a firm support for the
extension leaf. For bringing the knee-joints over thei
- folding point, when the exteinsion leaf ~hall bq returned
to the storage position, there is an activating rod 82
connecting the rod 70, which carries the extension leaf,
with the interconnecting rod 72 of the knee-joints. In
the levelling position the rod 82 has an inclined posi-
tion opposite the position of the knee-joints, in order
that the weight of the extension leaf will push the rod
opposite the angle of the knee joints and thereby pull
these over ~he angle or the changing position. ~he ex-
tension leaf will by its own weight, controlled by the
intermeshing between the pullarm and the cam disc, be
lowered to its lowermost position, wherea~ter the swi-
velling is initiated. At swivelling to the storage posi-
tion and to the levelling position the extension leaf is
supported by ball wheels mounted at ~he upper side of
the side beams 14a, 14b. This relieves the stud 34 and
.
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WO91/05496 PCT/DK90/002
16
consequently the positioning requirements are less
stringent. For ~he sake of good order it should be no-
ticed that the knee-joints and the pull arms at each
side are opposite each other, as the pull is reciprocal
at the swivelling of the pull arm 66.
The rotation o~ the cam disc is p~rovided by a cable
(see Figs. 9,11), where the cable 84 is put about the
cam disc in a trac~ 86 on the periphery between the
topmost and lowermost plate of the disc, as the edge ~8,
about which these are mounted, is retracted to the peri-
phery. For tightening of the cable the edge element 88
is disconnected and the ends rounded off towards the
centre topmost plate, wherein there is a slot 9O with a
spring 92, one end of which is fixed to the cam disc by
. a pin 82, and where the cable is put around the other
end of the spring. The cable is by one end fixed to the
end of a pull rod 96, which at the opp~osite end carries
an operating lever 10, which is outside the mounting
frame. Thei other end of the cable is f;ixed to the rod
against the lever. The mounting is made in a simple
manner by putting the ends of the cable~ in two tracks
closely together in the rod and binding a knot at the
ends of ~he cable, which is contained in a slot or at
the end in an oblique cut off of the rod. The rod ex-
tends in the entire length of the mounting frame and
engage the trac~ at the edge o~ the cam disc. The rod is
laid in a conducting tube 100, which by mountings is
mounted to the mounting frame, and is disconnected at
the cam disc for free movement of the cable.
By a pull of the lever, which mere~ly is a piece of
round bar steel welded to the end of the pull rod, the
cam disc is brought to swivel as a consequence of the ;-
cable b~eing put around the disc, which will release the
earlier described movements in the consistent order,
until the table is extended by the exte~nsion leaf. The
travelling of the lever is relatively long corresponding
: .... ,: . . ~ . . .................... . . . ~ .
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`` WO91/05496 PCT/DK90/002
17
to it being placed exactly below the end of the table
top concurrently with the two table top sections being
moved away form each other. This is psychologically
right for the user, that a pull at the operating lever
calls forth a comparable travelling of the table top
sections. The storage of the extension leaf happens
merely by pushing the lever. The extension leaf can be
locked in the extreme positions by a breaking device
which,in a simple manner consists of a pull rod having a
rectangular cxoss section and the steady tube a square
cross section such that the lever can be turned causing
the sides of the rod to contact with forwardly directed
ton~ues in the steady tube and by a key locking locks
the operating rod.
In the embodiment described the cam disc is brought
to rotation by a cable, however, a rack meshing gears at
thè periphery of the cam disc could also be used. The
rack could be placed at one of the table top sections,
such that this is utilized as an operating lever. The
rotation could also be undertaken by an electric gear
mo~or. The paralleloyrams at the sides for levelling and
lowering of the extension leaf could be replaced by
eccentric suspended elements. Thus a variety of dif-
ferent constructive solutions of details do not fall
outside the scope of the invention.
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