FR2648996A1 - IMPROVED SOFA BED MECHANISM - Google Patents

Abstract

Sofa bed mechanism comprising a support frame for a mattress M, said frame being foldable and retractable in the folded position in a box 1 defining the contours of the seat of the sofa bed, characterized in that it comprises a first constituent assembly the frame itself and formed by the first parts 14, 23, 24, 34 of two articulated sub-assemblies 6 interconnected by slats, means 44 for locking the first assembly in the folded position and a second assembly formed by seconds parts 11, 12, 20, 21 of the two sub-assemblies 6, for connecting the first assembly with the body 1 and for retracting therein the first assembly held folded by the locking device, part of the mattress M folded with the first assembly forming the seat of the sofa bed seat.

Description

The present invention relates to sofas

  beds and relates more particularly to the mechanics

sofa bed nisms.

  We know mechanisms of sofa beds formed by an articulated frame carrying a folding mattress completed by a fixed back padding

and removable seat cushions.

  The main drawback of

  known sofa beds is that they cannot

  wind be associated only with relatively thick mattresses

  low, which reduces the comfort of the sofa

  bed when used in bed and requires adding

  seat cushions when the sofa bed is

used as a sofa.

  The invention aims to remedy the drawbacks

  nient sofa beds of the prior art by creating a sofa bed mechanism which, while being

  relatively simple in construction and

  easy pulation, allow the use of a mattress of sufficient thickness to make the sofa bed

  comfortable whether used in bed or seat.

  Its object is therefore a

  sofa bed including a support frame for a mat-

  weary, said frame being foldable and retractable in the folded position in a box defining the contours of the seat of the sofa bed, characterized in that it comprises a first assembly constituting the frame proper and formed by first parts of two sub-assemblies articulated interconnected by slats, locking means of the first assembly in the folded position and a second

  set formed by second parts of the two sub-

  sets, connecting the first set with the

  body and retraction therein of the first set

  ble kept folded by the locking device, part of the mattress folded with the first set

  forming the seat of the sofa bed seat.

  The invention will be better understood using

  the description which follows, given only to

  as an example and made with reference to the accompanying drawings, in which: - Fig.1 is a side elevation view

  a sofa bed made using a follow-up mechanism

  vant the invention shown in the deployed bed position; - Fig.2 is a side elevational view of the mechanism in an intermediate position; - Fig.3 shows the mechanism in the semi-folded position before its introduction into the box defining the seat of the sofa bed; - Fig.4 shows the mechanism being tilted for its introduction into the body of the seat or its extraction from it; - Fig.5 shows the mechanism fully folded in the seat position; - Fig.6 is a schematic top view of the mechanism according to the invention. showing the structure of the mattress support surface; and - Fig.7 is a partial view on a larger scale showing the locking device

  in the folded position of the part of the support mechanism

both the mattress.

  In Fig.1, there is shown a sofa bed according to the invention comprising a box 1 for

  contain the sofa bed mechanism in the re- posed position

  folded and define the contour of the seat of the sofa

  bed. The body 1 has side walls such as the wall 2 carrying armrests, a front 3 of height less than that of the walls

  side 2 and a rear wall not shown.

  It is surmounted by a backrest of which only the padding 4 is visible in the drawings.

  The sofa bed mechanism according to the invention

  tion includes an articulated frame designated by the

general reference number 5.

  This frame is formed of two sub-

  articulated seeds such as the sub-assembly 6 represented

  felt in Fig. 1. each fixed by one of its

  mites i a side wall 2 of the body 1 of the cana-

  pe-bed and interconnected by wooden slats 7

  for example. as shown in Fig. 6.

  In Fig. 6, there is shown schematically-

  ment the sleeping surface of a sofa-bed according to the invention convertible into a double bed, the slats 7 which interconnect the articulated sub-assemblies 6 are in turn interconnected in

  longitudinal direction by a reinforcement strap

  ment 8 fixed in the middle of each of the slats for example by at least one rivet 9. Several straps of

  reinforcement of this type can also be pre-

  views. Referring more particularly to FIGS. 1 and 2. it can be seen that each of the articulated sub-assemblies 6 comprises a fitting 11 arranged diagonally against the inside of the side wall 2 of the body 1. At one of the ends of the fitting 11, constituted for example by a flat iron is articulated a connecting rod 12. By its opposite end to the fitting 11, the connecting rod 12 is articulated on a gusset 13 secured to the end of a first frame section

  14 located near the fixed backrest 4 of the sofa bed.

  The connecting rod 12 has a first tab 15 perpendicular

  to the direction of the connecting rod and to which

  fixed a tubular crosspiece 16 connecting the biel-

  the 12 with a corresponding connecting rod forming part of

  the other articulated sub-assembly 6. The connecting rod 12 comprises

  te a second tab 17 to which is fixed one end of a spring 18 whose other end is

  attached to the front 3 of the sofa bed body.

  The gusset 13 of articulation of the connecting rod 12 is also fixed -a backsplash 19 extending between

  the end of the mattress support frame and the back

  sier 4 and intended to retain the mattress M during

  folding the sofa bed.

  At its end opposite to the connecting rod 12,

  located at the bottom of the body, near

  mite from the front 3 thereof, the diagonal fitting 11 is connected to a bent piece 20 roughly square-shaped which, as shown in the drawings, almost always occupies a position in which one of its branches 20a extends approximately vertically, while its other branch 20b projects over the front 3 of the body of the

  sofa bed outside the perimeter of this box.

  The bent part 20 is not retracted internally

  of the body only when all of the machinery

  nique of the sofa bed is introduced into the body of the sofa bed At the free end of the bent piece 20 is articulated a connecting rod 21 whose opposite end is articulated in turn on the frame section 14 roughly at both third of its length from

gusset 13.

  The bent part 20 comprises, at the junction of these two branches 20a and 20b, a stop 22 for limiting the angular displacement of the connecting rod 21 relative to this bent part,

  The frame section 14 is part of a pre-

  mier together the sofa bed mechanism which will be de-

  written later, while the diagonal fittings 11 and the connecting rods articulated on these constitute a second assembly connecting the first assembly with the body of the sofa bed and retracting the first

together in the crate.

  At the end of the first frame section 14 opposite the gusset 13, a second frame section 23 is articulated. The length of the second frame section 23 corresponds to almost twice the thickness of the mattress M. On the second section of frame 23 is

  articulated in turn a third frame section 24.

  The relative movements of the first, second and third frame sections 14, 23 and 24 are controlled by a linkage comprising a

  rectilinear link 25 of which one end is articulated

  abutment near the end of the first frame section 14 close to its articulation on the second section 23. At its opposite end, the link 25 is articulated on a triangular rod 26 mounted oscillating on the second section 23 at a point

  articulation 27 and in turn connected by means of

  diary of a 28-piece articulation light

  triangular 29 integral with a first leg 30 articulated

  butted on the third frame section 24 by means of

a hinge pin 31.

  The articulation of the lumen 28 of the triangular connecting rod 26 on the triangular part 29 and the axis 31 of articulation of the first leg 30 on the third frame section 24, are arranged on two vertices of the triangular part 29 lying on a line corresponding to the direction of the third frame section 24. The third vertex of the triangular part

  29 which is offset downward from the direction

  tion of the third frame section 24, carries an axis 32 of articulation of a rod 33 connecting the first foot 30 or central foot with a fourth section 34

  of the frame, on which it is articulated by an axis 35.

  At the end of the rod 33 opposite the first leg 30, is articulated a rod 36 connected to the rod 33 by an axis 37 located below the axis 35

  of articulation of the rod 33 on the fourth section

  frame lesson 34. At its opposite end, the rod

  36 is articulated by an axis 38 at the upper end

  second foot 39 or front foot mounted oscil-

  lant on a leg 40 extending downwards, fixed to the

  fourth section of frame 34 near its ex-

  free end. 'The front leg 39 is articulated on the

leg 40 by an axis 41.

  When passing and keeping in the folded position, the resistance to folding of a

  comfortable mattress, that is to say a good thick-

high density.

  We can see more clearly in Fig. 2 that the

  fourth frame section 34 carries a support plate

  pui 42 intended to cooperate with a stop rod 43 provided on the first leg 30 in order to ensure during the

  folding of the mechanism a reduction of the ef-

  strong angular displacement of the fourth section of

  frame 34 in order to facilitate the locking of the sections

  lessons 23, 24 and 14 in the folded position by the

  foot 30 which drives the triangular piece

  laire 29 which, multiplied, pulls on the connecting rod

  gular 26, blocking between them the frame sections 23 and 24; the triangular connecting rod Z6 pulls on the

  connecting rod 25 which blocks between them the sections of

  dre 23 and 14. The fourth frame section 34 is locked to the second section 23 at the end of movement by a locking device fixed at the end

free from the frame section 34.

  The device for locking the fourth frame section 34 relative to the second section 23 in the folded position of the frame, comprises a fitting 44 fixed to the second section 23 and cooperating with a latch fixed to the free end of the fourth section of

  frame 34 beyond the second foot 39 hinged thereon

  this. for example on a cross member 34a completing the

O10 frame.

  The lock 45 comprises a piece forming bolt 46 mounted for rotation on an axis 47 and returned by a helical spring 48 in the closed position in which it engages with the fitting 44 at

by means of a lateral notch 49.

  The part 46 has at its free end an operating surface 50. At the free end of the fourth section 34 is also fixed a handle 51 intended to facilitate the manipulation of the frame during

  folding operations thereof.

  How the sofa bed works

  according to the invention will now be described with reference to

Refer to Figs 1 to 5.

  As seen in Fig. 1, the sofa

  bed is in the fully unfolded position, in which it acts as a bed. The various frame sections 14.23. 24 and 34 are aligned with each other and the feet 30 and 39 are in positions perpendicular to the direction

  general of the frame and form with the connecting rods 12 re-

  linked to the diagonal fittings 11 carried by the body

  1, supports for the sleeping surface.

  We also note that the mattress M

  used is a one piece mattress.

  When we want to fold the sofa bed, we

  raises the frame by its fourth section 34, with

  of the handle 51, which causes an angular displacement of the second section 23 relative to the first section 14. of the third section 24 relative to the second section 23, as well as of the fourth section 34 relative to the third section 24. These various displacements angular are facilitated by the presence

  at least one return spring 53 fixed between the gqus-

  set 13 and the third frame section 24.

  During this first part of the ope-

  folding ration, the first frame section 14 remains stationary. The relative angular displacements of the second, third and fourth sections relative to each other, and relative to the first section 14, cause, due to the presence of the control linkages formed by the rectilinear link 23, the triangular link 26, the triangular part 29 secured to the first foot 30. the rods 33 and 36 connecting the foot 30 with the fourth frame section 34 and with the second foot 39, the progressive folding of the feet 30 and 39 by an angular displacement of these feet on their respective axes of articulation 31 and 41, respectively towards the third frame section 24 and the fourth

frame sections 34.

  This movement is visible in Fig. 2 which represents the mattress support frame in position

  partially folded, the folds of the M mattress appear

  health at the level of the joints of the second and three

  frame sections with respect to the first, and

  fourth frame section relative to the third.

  We also see in Fig. 2, that each

  each of the fourth frame sections 34 is provided with its end situated opposite the corresponding third frame section 24, with a tip 34b cooperating with

  a stop surface 24b provided at the corresponding end

  of the third frame section 24. The stop 24b is intended to keep the third section 24 in alignment with the fourth section 34 when the

  sofa bed is in the unfolded position (Fig. 1).

  Continuing the folding operation started in Fig. 2, we end up by folding the

  third frame section 24 around the second section

  frame lesson 23 and by folding the fourth section

  frame lesson 34 on the third frame section 24, to an assembly whose relative position of the elements

is shown in Fig. 3.

  In this figure, we see that the second

  frame section 23 occupies a perpendicular position

  the first section 14 while, due to the proportions chosen for the link 25 and the triangular lever 26, the third frame section 24 occupies a position roughly parallel to the first frame section 14. while the fourth frame section 34 is completely folded over the third frame section 24.the first and second legs 30. 39

  also being folded into the common plane of the three

  fifth and fourth frame sections 24 and 34.

  This flat folding of the third and fourth

  third sections of frame and feet 30, 39 is obtained by judicious positioning of the articulation points of the feet 30, 39 with respect to their corresponding frame sections 24, 34 on the one hand, and of the articulation axes of the rods 33 and 36 on the one hand between them, and on the other hand, with the various

  bodies with which they are associated.

  In the folded position of the sleeping surface shown in FIG. 3, the mattress M is folded back on itself at S between the articulated sub-assemblies 6 so that the part of the mattress resting on the first frame section 14 is in contact with the part supported with the third frame section 23 to which the part of the mattress supported by the fourth frame section 34 is superimposed. The assembly is held in this position by the locking device whose fitting 44 cooperates with the latch piece 46 (Fig. 7). The fold of the mattress which results from the folding of the fourth frame section 34 onto the third frame section 23 is held in place by the backrest 19 at a

short distance from backrest 4.

  We see that in the position shown in Fig.3, the frame serving as a support for the mattress

  is folded in on itself and locked by the device

  locking tif 7 shown in Fig. 7 and therefore constitutes a first assembly formed of first parts of the articulated sub-assemblies6 and ready to be moved again for its retraction

in the bed of the sofa bed.

  In this position, the connecting rods 12 and 21 as well as the bent piece 20, are always in the same position as they occupied when the

  sofa bed was in the fully extended position.

  These various elements form the second parts of the articulated sub-assemblies 6 and constitute

  the second introductory set of the first sub-in-

  appears in the bed of the sofa bed.

  In order to ensure the introduction of the first assembly into the body 1, the first Â1 sub-assembly is tilted by acting on the handle 51 to cause the first frame section 14 and the entire assembly locked on it to oscillate. around the room

  angled 20 via the connecting rod 21 and

  turn of the diagonal fitting 11 via

the connecting rod 12.

  During this switchover, the first

  seems defined above comes to occupy an intermediate position shown in Fig.4. We see that in

  this position, the connecting rod 21 has turned around the former

  corresponding end of the bent piece 20 until it is stopped in rotation by the stop 22, while the connecting rod 12 articulated at the upper end of the diagonal fitting 11 on the one hand and on the gusset 13 on the other hand, has turned around the end of the diagonal fitting 11, so as to bring the gusset 13 and the corresponding end of the first section 14 of the frame in the low position, close to the bottom of the body 1 while causing the tension of the return spring 18 The assembly being in the position shown in Fig.4, is ready to be definitively

retracted into the body 1.

  To this end, it suffices to push on the first assembly to cause the bent pieces 20 to rotate about their respective hinge axes on the diagonal fittings 11. During this last movement, the frame section 14 oscillates.

  with respect to the connecting rods 21 and with respect to the ends

  opposite half of the diagonal fittings 11 through the

  connecting rods 12 to come and occupy a posi-

  fully retracted into the box shown at

Fig. 5.

  The height under the backrest 4 is such that the mattress M can penetrate under the backrest and the

  upper surface of its part supported by the qua-

  third section of frame 34 thus constitutes the seat surface of the sofa when the latter is in

sofa position.

  To ensure the exit of the first assembly out of the box 1. it suffices to pull on the handle 51 while lifting slightly. The return springs 18 which are under tension contribute to the output of the

  first set out of the box 1.

  When the mechanism is found in the

  position shown in Fig. 3, just dever-

  rust the first set by action on the bolt 46

  and ensure the deployment of the framework by acting

days on the handle 51.

  The relative synchronous movement of all moving parts allows that at the end of movement of the

  feet 30 and 39, are in appropriate positions

  requested to serve as support for the framework.

  In addition, the deployment of the first

  seems to cause the springs 53 to be put under stress which, by the resistance which they oppose, compensate

  the effects of the weight of the frame and avoid using it

  tor to have to retain the mechanism during its deployment.

  Thanks to the arrangement that has just been

  crit, it is possible to use mattresses of sufficient thickness so that in the folded position, they

  constitute a sufficiently conforming seating surface

  table for the user and that in the unfolded position, they form in cooperation with the slats 7, a sleeping surface practically equivalent to that

of an ordinary bed.

  We can also see that the arrangement follows

  The invention allows the use of a mattress in one

single piece.

  The various constituent elements of the

  seems to exit and re-enter the frame supporting the

  mattresses, are sized to present movements

  synchronized deployment and folding. In the embodiment which has just been described, when the sofa bed is in position

  deployed from bed, the fourth section 34 is perfect-

  aligned with the other sections of the frame and

  especially with the third frame section 24.

  However, if one wishes to be able to give to

  the seating surface of the sofa bed

  laying more on that of a sofa, i.e.

  lowering slightly towards the backrest, it is pos-

  likely to provide means of articulation of the

  third frame section 34 relative to the rest of the

  frame, made in such a way that in the

  folded, the fourth section is slightly inclined towards the ground with respect to the rest of the frame, while making the mattress with a progressive wedge-shaped thickening in the region of the supported mattress

by the fourth section.

  Under these conditions, the mattress will be

  flat when the frame is in the extended sleeping position and forms a slight recess

  towards the backrest when the mattress is folded up.

  To achieve such a result, it suffices to provide second feet 39 slightly shorter than the first articulated feet 30 and to move the

  joints of feet 39 with their rods

  tction 36, so that in the deployed position the fourth section has the desired inclination to compensate for the thickness of the seat

folded position of the sofa bed.

Claims (7)

  1. Sofa bed mechanism comprising a frame for supporting a mattress (M), said frame being foldable and retractable in the folded position in a box (1) defining the contours of the seat of the sofa bed, characterized in that that it comprises a first assembly constituting the frame proper and formed   by the first parts (14,23,24,34) of two sub-   articulated assemblies (6) interconnected by slats (7), means (44,45) for locking the   first assembly in the folded position and a second   seems to be formed by second parts (11,12,20,21) of the two sub-assemblies (6), connecting the first   together with the body (1) and retraction therein   this of the first set kept folded by the dis-   positive locking, part of the mattress (M) re-   folded with the first set form the seat cushion age of the sofa bed.   2. Sofa bed mechanism according to resale   dication 1, characterized in that said first set   ble forming the actual frame includes a pre-   mier section of frame (14) articulated on the second   seems, a second frame section (23) articulated on the first frame section (14) and on a third frame section (24), the first frame section (14) being further connected to the third frame section (24 ) by a control linkage comprising a rectilinear link (25) articulated on the first section (14) and a triangular connecting rod articulated on the third section (24) on the one hand directly (27)   and on the other hand by means of a light (28), by the   intermediate of a triangular piece secured to a first leg (30) also articulated on the third frame section (24) and a fourth frame section (34) articulated on the third section (24) and further connected to this one by a first rod   (33) connecting the first leg (30) with the fourth-   me frame section (34) and a second rod (36) connecting the first rod (33) with a second leg (39) articulated on the fourth frame section (34). 3. Sofa bed mechanism according to one of the   claims 1 and 2. characterized in that the second   set comprises, associated with each of the sides (2) of   the body (1) a fitting (11) fixed to the side (2) cor-   correspondent of the cash register. an articulated connecting rod (12)   on the one hand on the fitting (11) and on the other hand i the ex-   free end of the first frame section (14), a bent piece (20) articulated by one of its branches (20a) on the other end of the fitting (11) and by its other branch (20b) on a connecting rod (21 ) link   with said first frame section (14), said connecting rod   the (12) connecting the fitting (11) with the end   of the frame section (14) comprising a tab on the   which is fixed the end of a spring (18) of which   the other end is fixed to the body (1).   4. Sofa bed mechanism according to one of the   claims 2 and 3. characterized in that the third   the sixth frame section (24) is also connected to the ex-   end of the first frame section (14) opposite its articulation on the second section (23) by at least one spring (33) for returning and retaining the various elements of the first assembly during deployment of the sofa.   5. Sofa bed mechanism according to one of the   vendications 3 and 4. characterized in that the bent pieces (20) of the second set each include a stop (22) for limiting the angular displacement of the connecting rod (21) corresponding to the bent piece (201 with the first section of said connecting rods (21) in the abutment position defining one of the pivot axes of the first frame section (24), on which the first assembly folded is locked in order to retract said first assembly into the body (1) or its exit outside of it.   6. Sofa bed mechanism according to one of the   claims 3 to 5, characterized in that each   bent piece is articulated on the fitting (11) cor-   corresponding in the lower part of the box (1) to   near the front (3) of the body and   kills due to tilting around the end   of the fitting (11) a retracting member of said pre-   mier together in the crate (1) and its out-exit of it.   7. Sofa bed mechanism according to one of the   Claims 1 to 6, characterized in that the slats   (7) connecting the articulated sub-assemblies (6) to constitute the frame proper are connected between   they in longitudinal direction by at least one reinforcement bar (8).   B. Sofa bed mechanism according to one of   claims 2 to 7, characterized in that said pre-   working together is provided with means (42,43) of   plication of the angular displacement force of the second, third and fourth frame sections (23, 24,34) in order to facilitate blocking and locking of these sections with the first frame section (14) using the device lock (44,45) despite the resistance offered by the folding force of the mattress (M).   9. Mechanism according to one of the claims   tions 2 to 8, characterized in that said first section   çon of frame (14) comprises at its end close to the backrest (4), a backrest (19) for retaining the mattress   (M) during the folding of said first set.   iS 10. Mechanism according to one of the claims   tions 2 to 9, characterized in that in the deployed position the fourth frame section (34) has a slight   tilt down from the third section   lesson (24) and in that the portion of the mattress (M) sup-   carried by the fourth section (34) has a su-   progressive wedge-shaped thicknesser intended to give, in the folded position of the sofa bed, a surface   seat with a slight recess towards the back- sier.