The present invention relates to a linear dual actuator for adjustment of two adjustable sections in a piece of lying and/or sitting furniture. The invention also relates to a piece of lying and/or sitting furniture having two adjustable sections and a linear dual actuator for adjusting the two sections. Electrically driven linear dual actuators for beds for domestic use, today known as adjustable beds, said beds having an adjustable back rest and leg rest section, were invented in the late 1980s, cf. e.g. DE 38 42 078 C2 to Dietmar Koch and EP 0 372 032 B2 to Eckhart Dewert. In the bed, there is a transverse axle for the back rest and leg rest section, respectively, where an arm is attached to the axles, said arm is actuated by the dual actuator for adjustment of the sections. The dual actuators comprise a housing of two half-shells made from plastic. Each end of the housing comprises an electric drive, one for the back rest section and another for the leg rest section. The two drives have the same base construction and comprise a spindle which with one end is embedded in the housing. On the spindle, a sliding element is arranged with a spindle nut in engagement with the spindle. When the spindle is rotated, the sliding element is displaced in one direction or the other depending on the direction of rotation of the spindle. In the upper side of the housing in the area of the sliding element, a recess is located in the sides of the housing for receiving the transverse axle of the bed, such that the arm on the axle reaches into the housing and can be actuated by the sliding element of the corresponding drive. The dual actuator is retained on the axle by means of a cover on the housing, where the cover is slid over the axle .

With time, these linear dual actuators have been developed further. For example, in the original construction, the motors extend perpendicularly out from the side of the housing which is a complex shape. In DE 10 2007 060 112 A1 and DE 10 2007 062 300 A1 , both to Kurt Schmid, a solution is suggested where the electric motors stand upright. This, however, leads to a relatively large height of the housing but also a relatively large width. The reduction of the width of the housing is sought solved by means of a convex area of the housing for accommodating the electric motors, which, however, complicates the mould and results in the same disadvantages as the traditional horizontal location of the electric motors. This is sought solved in DE 20 2013 102 151 U1 to Sino- Europe GmbH & Co. KG by constructing recesses in the housing such that an adjacent dual actuator with the convex area accommodating the electric motors can reach into these recesses during shipping. However, this further complicates the mould. Strength-wise, it is necessary to use plastic with good strength properties, and further to the mould being large and complicated, the housing constitutes a substantial part of the production costs of the dual actuator without achieving the desired strength. Moreover, fire safety for a housing made of plastic is an issue, as fire-retardant plastic materials are relatively expensive. Dual actuators are large, which results in relatively large transportation costs from the factory to the bed manufacturer. The object of the invention is to provide a dual actuator which is cheaper to manufacture and is stronger than the known constructions.

According to the invention, this is achieved by constructing the linear dual actuator as described in claim 1, namely in that it comprises a carrying element in the shape of a rod which can be mounted on the rotary axles of the back rest and leg rest sections, and where the drives are single actuators connected with one end to the rod and with the other end to the arm of the rotary axle, respectively. This is a simple, strong and mounting friendly construction. Similar to the known linear dual actuators, this type of actuator can also be constructed in a way which enables mounting without the use of tools. When packed, it also only takes up a relatively modest amount of space. Moreover, the construction is flexible, as it can easily be configured to fit a given distance between the rotary axles of the piece of furniture, just as single actuators which meet the requirements for the load may be chosen.

The carrying rod can be a solid rod, but in a preferred embodiment, the carrying rod is tubular. The rod can be made from different materials, but for strength and stability reasons a rod made of metal is preferred. The rod can likewise have different shapes configured for the specific construction. In an embodiment, the rod has a quadrangular cross section, preferably square. In an embodiment, the tubular rod is equipped with a plate member on its underside or upper side for mounting the single actuators by means of their rear mounting or front mounting. Thus, the dimensions of the rod can be smaller. It should be noted that the rod can also have a T-shaped cross section. If necessary, the shape of the vertical part of the rod can be adapted to the preferred position of the single actuators.

The carrying rod can be mounted on the rotary axles in different ways. The rod can, for example, have a transverse eye with which it can be slid over the rotary axle. For mounting reasons, however, a solution is preferred where the carrying rod can be mounted on a finished bed frame. To this end, the rod can be furnished with a bearing bush with which it can be placed over a rotary axle and possibly also with a locking element for securing the rotary axle in the bearing bush. In a special embodiment, the end of the carrying rod, preferably both ends, are equipped with a hook-shaped bracket for mounting the rod on the respective rotary axles for the back rest and leg rest sections. The rod can thus simply be mounted by hooking it onto the rotary axles. In an embodiment where the rod is tubular, the hook-shaped bracket is constructed with an end which fits into the hollow of the rod and is equipped with at least one pin which fits into a corresponding hole in the rod, such that the bracket with a snap-lock effect is locked to the rod.

In an embodiment, the end piece is outlined by an edge relative to the rest of the bracket. This edge functions as a stop against the end of the tubular rod, i.e. a precise positioning of the circular pins relative to the holes in the rod is achieved. Equally important is it that the compressive forces on the bracket via the edge is transferred directly to the side walls of the tubular rod. During idle periods and when raising and lowering a section, the linear dual actuator is only exposed to compressive forces.

In an embodiment, the end piece is, preferably at its free end which is guided into the rod, constructed with a block shaped piece having a cross section which corresponds to the opening of the tubular rod by which the hook-shaped element is secured against rotation. This also ensures that the hook-shaped element cannot unintentionally be twisted off the rotary axle.

The hook of the hook-shaped element can be designed in various ways, it could, for example, be an arched section e.g. made from metal. Preferably, at least the hook-shaped part of the hook-shaped element is made from a flat element, which provides an optimal contact surface for the rotary axle. To this end, the hook-shaped element is preferably made from plastic. The contact surface itself for the rotary axle can in this regard be made from a special plastic with self-lubricating properties.

In an embodiment where the end piece has a block-shaped section, the flat element extends in a straight course from the end of the block which faces towards the hollow of the rod and continues as an arched section, that again continues as a straight section, thus forming a hook. The straight section terminates a short distance before the block such that it can be guided over the rotary axle. However, the course is so long that it during mounting of the hook-shaped element is inserted into the hollow of the rod . The circular pins are expediently constructed on the straight courses of the flat element. When the bracket with the block is inserted into the rod and further in, the two straight courses of the flat element will resiliently give in , and when they engage the end of the rod with the edge, the circular pins will, due to the resilient effect, snap outwards with a snap-locking effect and enter into engagement with the corresponding holes in the rod. The end piece is thus secured to the rod.

The bearing seat for the rotary axle is constituted by an internal surface of the end piece, specifically the internal surface of the arched part as well as the portion leading to it, which constitutes the contact surfaces. Thus, the rotary axle is retained at a distance from the end of the tubular rod, thus preventing it from brushing against the tubular rod.

In another embodiment, the hook-shaped element is constituted by a flat element with two straight sections intended for insertion into the hollow of the rod, and where the two pieces are connected with an arched section, which constitutes the hook-shaped section. The invention further relates to a piece of lying and/or sitting furniture with two adjustable sections and a linear dual actuator for adjusting the sections according to claim 11. The invention will be described more fully below with reference to the accompanying drawing of the linear dual actuator, in which: Fig. 1 shows a perspective view of a dual actuator mounted on rotary axles,

Fig. 2 shows the dual actuator shown directly from one side,

Fig. 3 shows the dual actuator shown directly from the other side,

Fig. 4 shows the dual actuator shown directly from above,

Fig. 5 shows an exploded view of a rod-shaped element of the dual actuator,

Fig. 6 shows a perspective view of the single actuator shown on the left in Fig. 4,

Fig. 7 shows a longitudinal section through the single actuator shown in Fig. 6,

Fig. 8 shows a different embodiment of the dual actuator, and

Fig. 9 shows a schematic view of a slatted bed shown with raised back rest and leg rest section. The embodiment shown in Figs. 1-7 relates to a linear dual actuator 1 according to the invention for adjustment of a back rest and leg rest section 2,3 of beds. As carrying element 4, the dual actuator comprises a rod 5 in the shape of a tubular profile, here having a square cross section. At each end, the rod 5 is furnished with a hook-shaped bracket 6,7 for mounting the rod 5 on the respective rotary axles 8,9 for the back rest and leg rest section 2,3. The brackets 6,7 comprise an end piece 10 in the shape of a block having a square cross section intended for insertion into the hollow of the tubular rod 5. Extending from one end of the end piece 10, is a flat element 11 with a straight section 11a which continues as an arched section lib which again continues as a straight section lib which terminates a short distance before the block 10, thus forming a hook with which the bracket 6,7 and thus the rod 5 can be hooked onto a rotary axle 8,9, typically without the use of any kind of tools. Before the straight sections 11a, 11c of the element 6,7 continues as the arched section lib, there is a ledge in the element, which creates an edge lid on the outer side of the element with which it rests against the end 5a of the tubular rod 5. A distance before each of the edges lid, there is a circular pin 12 intended for engagement with a corresponding circular hole 13 in the upper side and the underside of the tubular rod 5. When the bracket 6,7 with the end piece 10 and the U- shaped element 11 is guided into the rod 5 and further in, the two flat elements 11a, lib will resiliently give in and when they with the edge lid engage the end of the rod 5a , the circular pins 12 will due to the resilient effect snap outwards and enter into engagement with the holes 13 in the rod. The bracket 6,7 is thus attached to the rod 5. The seat for the rotary axle 8,9 is constituted by an internal surface in the end piece 6,7, namely the internal surface of the arched section lib as well as the portion leading up to it which forms the contact surfaces lid. Thus, the rotary axle 8,9 is retained at a distance from the end 5a of the tubular rod 5, thus preventing it from brushing against the tubular rod.

The dual actuator 1 can be disassembled by using a tool to push the two pins 12 on the bracket 11 into the tubular rod 5 such that they enter out of engagement with the holes 13, and subsequently push/pull the brackets 6,7 out of the rod 5. The underside of the tubular rod 5 is furnished with a plate member 14 for mounting the single actuators 15,16 with their rear mounting 17. To this end, there is a hole 18 for a locking pin 19 in the plate member 14 for each of the actuators. In order to reduce friction, and thus noise and wear, the holes are equipped with nylon bushings 20.

The dual actuator comprises two single actuators 15,16, one for adjustment of the back rest section 2 of the bed and another for adjustment of the leg rest section 3 of the bed. The single actuators comprise a housing 21 having an outer tube 22 for an inner tube 23 attached to its front end, said inner tube 23 can be moved inwards and outwards like a piston. The inner tube 23 is driven by a spindle unit, where the spindle 24 is driven by a reversible electric motor 25 through a gear 26, and where the inner tube 23 is secured to the spindle nut 27. When the electric motor 25 is driven in one direction, the spindle nut 27 is moved outwards on the spindle 24, and the inner tube 23 is thus displaced outwards. When the electric motor 25 changes the direction of rotation, the spindle nut 27 is moved inwards on the spindle 24, and the inner tube 23 is retracted. The rear end of the housing 21 is equipped with a rear mounting 17, here in the shape of a fork mounting, and the free end of the inner tube 23 equipped with a front mounting 29 in the shape of an eye. The spindle nut can be secured against rotation in the outer tube 22 or via the construction in which the linear actuator is mounted. The electric control system for the dual actuator is here a primary control box 30 secured to one of the single actuators 15, and a secondary control box 31 secured to the other single actuator 16. The dual actuator can be operated by means of a wireless hand control, alternatively wire-connected. It will also be possible to operate it by using a control panel. It should be understood that the control boxes can also be mounted separately from the single actuators if necessary, which in general provides more flexibility when mounting the dual actuator.

Fig. 8 of the drawing shows another embodiment of the dual actuator, where the carrying rod 5 is secured to the rotary axles by means of a flat C-shaped bracket 32, where the bracket with the arms 32a, 32b protrudes over the upper side and underside of the rod 5 and is secured with a through-going bolt 33. The bearing seat for the rotary axle 8,9 is constituted by a curved surface on a plastic stopper 34, inserted into the end of the rod 5 which is a tubular profile, as well as the inner side of the arch 32c of the C-shaped bracket, which is also made of plastic. The C-shaped bracket 32 can naturally also be made of metal and be furnished with a plastic insert in the curved surface, which constitutes the bearing seat. The single actuators 15,16 - here indicated by a double-arrow - are secured to the carrying rod 5 with a bracket 35 having a square cross-section, enabling it to be slid over the rod 5. For mounting the single actuators 15,16 by means of their rear mounting 17, each side of the underside of the bracket 35, which is a bent plate, is equipped with a flap 35a having two holes 35b. The bracket 35 is secured to the rod by mounting of the single actuators, alternatively it can be secured by means of screws.

Fig. 9 is a purely schematic view of a slatted bed 36 comprising a frame 37, in which a back rest section and an articulated leg rest section are embedded. For the back section 2, a transverse axle 8, to which an arm 38 is secured, is embedded in the frame 37. A rod 40 connected to the back rest section 2 is secured to each end of the axle, said rod is rotatably embedded in the frame 37 with the end facing towards the center of the frame 37. In a corresponding manner, there is a transverse axle 9 with an arm 39 for the leg rest section 3 which likewise is rotatably embedded in the frame 37 with the end facing towards the center of the frame 37. On either end of the axle 9, a rod 41 is in a similar manner connected to the leg rest section. When the dual actuator is activated, the axles 8,9 will rotate and the arms 40,41 on the ends hereof will raise or lower the back rest and leg rest section 2,3. It is understood that the single actuators 15,16 in the dual actuator can be activated independently of each other, such that the back rest and leg rest section 2,3 can be adjusted separately.

As for example shown in Fig. 1, the arms 38,39 on the rotary axles 8,9 are constituted by a U-shaped plate member having a bottom piece 38a and two wall pieces 38b. In the upper end of the two wall pieces 38b, there is a hole for a rotary axle 8,9, such that the arm 38,39 can be slid over this and be secured, e.g. by spot welding. In the lower end of the two wall pieces 38b there is a hole for an axle pin 40 for securing the front mounting 29 of the single actuator 15. The distance between the two wall pieces 38b of the arms 38 are adapted to the length of the front mounting 29, such that this is secured in the sideward direction of the rotary axle. Thus, a stable and secure mounting of the single actuator is achieved. In the drawing, the single actuators 15,16 are shown mounted with their rear mounting 17 to the carrying rod 5 and with the front mounting 23 to the arm 38,39 on the rotary axles 8,9. It is, however, understood that the single actuators may just as well be mounted with the rear mounting 17 to the arms of the rotary axles and with the front mounting 23 to the carrying rod 5. Alternatively, one actuator can be mounted in one way and the other can be mounted in the other way depending on the specific construction of the piece of furniture, which is another advantage of the invention.

It should moreover be noted that the same references numerals are used in the description and the drawing for the same part of the construction. Thus, the base construction of the single actuators is the same, for which reason only one of them has been described, and the same applies e.g. for the brackets ,7 on the carrying rod 5. In the drawing, the brackets 6,7 face in different directions, i.e. with the opening for the hook facing upwards and downwards, respectively. This is another advantage of the invention, as it can be configured for the relevant construction of the piece of furniture. According to the invention, the dual actuator has the following embodiments:

Linear dual actuator for lying and/or sitting furniture having at least two adjustable sections (2,3), where each section comprises an axle (8,9) with an arm (38,39), where the sections (2,3) are adjusted by rotating the axle (8,9) by actuating the arm (38,39), and where each end of the dual actuator comprises a drive with an electric motor (25), a transmission (26) and a spindle unit in driving connection with the electric motor through the transmission (26),

where the spindle unit comprises a spindle (24) and a spindle nut (27) as well as a sliding element (23) connected to the spindle unit (13), and where the sliding element (23) is configured to be brought into engagement with the arm (38,39) of the rotary axles (8,9) for adjustment of the sections (2,3),

the dual actuator comprises a carrying element (4) configured for mounting on a piece of lying and/or sitting furniture, and where the drives in the dual actuator are single actuators (15,16) which at a first point on the single actuator (15,16) is connected to the carrying element (4) and at a second point on the single actuator

(15,16) is configured to be brought into engagement with the arm (38,29) of the rotary axle (8,9), respectively.

Linear dual actuator where the carrying element (4) is configured for mounting on the rotary axles (8,9) of the sections (2,3) .

Linear dual actuator where the carrying element (4) is a tubular profile, expediently having a square cross- section.

Linear dual actuator where each end of the carrying element (4) is equipped with a hook-shaped bracket (6,7) configured for mounting of the carrying element (4) onto the respective rotary axles (8,9) for adjustment of the sections (2,3) . Linear dual actuator where the hook-shaped bracket (6,7) comprises an end piece (10) configured for insertion into a hollow of the carrying element (4) . Linear dual actuator where the end piece (10) and/or the carrying element (4) is equipped with locking means for securing the end piece (10) in the hollow of the carrying element ( 4 ) . Linear dual actuator where the locking means are designed as at least one pin (12) on the bracket (6,7), where the pin (12) is configured for engagement with a counterpart in the shape of a hole (13) in the carrying element (4), such that the bracket (6,7) is locked to the carrying element (4) by means of a snap-locking effect.

Linear dual actuator where the end piece (10) is outlined by an edge (lid) relative to the remaining part (11) of the bracket (6,7), where the edge functions as a stop against the end (5a) of the carrying element (4) .

Linear dual actuator where the end piece (10), preferably at the free end which is guided into the hollow of the carrying element (4), is constructed with a block-shaped piece having a cross-section which corresponds to the opening of the hollow of the carrying element (4) .

Linear dual actuator where at least the hook-shaped part (lib) of the hook-shaped element (6,7) is constituted by a flat element.

Linear dual actuator according where the hook-shaped element is constructed with a bearing seat for a rotary axle (6,7), where the bearing seat is arranged such that it is free of the rod (5) when the hook-shaped element is secured to this. Linear dual actuator where the dual actuator comprises a plate member (14) adapted for mounting on the carrying element (4) and configured for mounting of the single actuators (15,16) . Linear dual actuator where the single actuators (15,16) comprise a rear mounting (17) or a front mounting (29), and where the point in which the single actuator (15,16) is connected to the plate member (14) is located either in the rear mounting (17) or in the front mounting (29) .

A piece of lying and/or sitting furniture having at least two adjustable sections (2,3), where each section comprises an axle (8,9) with an arm (38,39), where the sections (2,3) are adjusted by rotating the axle (8,9) by actuating the arm (38,39), comprising the dual actuator according to one or more of the claims 1 to 13.