CN113142861B - Mechanical stretching device for a movable seat unit and seat unit - Google Patents

Abstract

The invention relates to a mechanical stretching device for a movable seating unit, comprising: -a tilting mechanism (2) comprising a multi-bar mechanism and for attachment to a seat portion, a backrest and a footrest of the seat unit, configured to enable a sequential or reverse sequential shift of the seat unit from a sitting position, in which the footrest is folded under the seat portion, to a TV position to a lying position; in the TV position, the footrest is positioned in front of the seat portion, the angle between the seat portion and the backrest remaining substantially the same as in the sitting position; in the recumbent position, the footrest remains in substantially the same state as in the TV position, the angle between the seat portion and the backrest being increased relative to in the TV position; the tilting mechanism (2) is designed such that the seat unit can be shifted between the sitting position and the TV position by means of an electric actuating unit (7), while the seat unit can be shifted between the TV position and the lying position by means of a non-electric actuating means only.

Description

Mechanical stretching device for a movable seat unit and seat unit

Technical Field

The present invention relates to a mechanical stretcher for a movable seating unit and a seating unit including the mechanical stretcher.

Background

A variety of seating units for movable seating units, such as rocking chairs, sofas with rocking function, are known in the prior art. The seating unit typically has a base, a back rest bracket, a seat bracket, and a recliner mechanism. The seating unit is convertible between a sitting position, a TV position, and a lying position. However, the known seat units either perform the above-mentioned position change completely manually under the operation of the user or automatically completely electrically. In the above-described design, since the seat unit needs to be switched between the above three positions, the connection between the back bracket, the seat bracket, and the reclining mechanism is complicated, and the number of necessary parts is large, which results in a higher cost.

In other known designs, the seat unit has both a manual and an electric operating system, but in each case a switching element, for example a switching handle or a switching button, is provided for switching back and forth between the manual and the electric operating system. When a user wishes to switch the manual operating system to the electric operating system or vice versa, he must, for example, pull the switch handle in order to complete the activation of the other operating system. Obviously, this design is more complex in construction, leading to higher risk of failure and higher manufacturing and maintenance costs.

Disclosure of Invention

The invention aims to solve the technical problem of providing a seat unit which is simpler in structure, simpler and more convenient to operate and lower in manufacturing cost.

To solve the above-mentioned technical problem, the present invention provides a mechanical stretching device for a movable seat unit, the mechanical stretching device comprising:

-a tilting mechanism comprising a multi-bar mechanism and for attachment to a seat portion of the seat unit, a backrest and a footrest configured to enable a sequential or reverse sequential shift of the seat unit from a sitting position in which the footrest is stowed under the seat portion to a TV position to a lying position; in the TV position, the footrest is located in front of the seat portion, and the relative position between the seat portion and the backrest remains substantially the same as in the sitting position. In the recumbent position, the relative position between the footrest and the seat portion remains substantially the same as in the TV position, and the angle between the seat portion and the backrest increases relative to in the TV position. It is noted that the terms "substantially identical" and "identical" as used herein mean that the relative position between the seat portion and the backrest (e.g., the angle formed by the two) and the relative position between the footrest and the seat portion (e.g., the angle formed by the two) are unchanged or are not easily perceived by the user even if there is a change, such as an angle change of no more than 2 °, preferably no more than 1 °.

According to the invention, the tilting mechanism is configured such that the switching of the seat unit between the sitting position and the TV position can be achieved by means of an electric actuating unit, whereas the switching of the seat unit between the TV position and the lying position can only be achieved by means of non-electric actuation, for example manual, hydraulic, pneumatic or spring actuation.

The invention is based on the idea that the electric actuating unit only has to take care of the change between two positions, namely the sitting position and the TV position, whereas the change between the TV position and the lying position has to be realized by the electric actuating unit, so that the relevant design is simpler and the manufacturing cost is lower.

In a preferred embodiment, the change of the seat unit between the TV position and the lying position can be effected by manual force, wherein the centre of gravity of a user sitting on the seat falls on the back rest bracket when the user is pressed back against the back rest, whereby the force exerted on the back rest bracket enables the tilting mechanism to be changed from the TV position to the lying position; and when the user gets up to shift the center of gravity forward from the back rest support to the seat support, the reclining mechanism can be reset from the lying position to the TV position by canceling the force applied to the back rest support.

The advantage of this design is that the user can simply utilize his own weight to switch between the TV position and the lying position by leaning back and rising forward without having to provide additional switching elements between the electric drive system and the manual drive system, such as a switching handle, a switching button, etc.

In a preferred embodiment, the tilting mechanism is configured for a pendulum or swing-type seat unit, which allows the seat unit to swing or swing back and forth relative to the floor in the sitting position, while does not allow the seat unit to swing or swing back and forth relative to the floor in the TV position and in the lying position. To achieve this, the tilting mechanism comprises a swing limit mechanism designed to allow forward and backward swinging of the Xu Bu support and the backrest support relative to the base in the sitting position and to prevent forward and backward swinging of the seat support relative to the base in the TV position and the lying position.

In a preferred embodiment, the mechanical stretching device comprises a support assembly for direct or indirect support on the ground, preferably for providing a rocking or swinging function for the seat unit.

In a preferred embodiment, the tilting mechanism comprises a leg extension unit for mounting a footrest, a seat support for mounting a seat part and a backrest support for mounting a backrest, which are connected in series in a pivotable manner.

The leg telescopic unit is connected with a front cross rod, the seat support is fixedly connected with a rear cross rod, and the front cross rod can move forwards relative to the rear cross rod through the electric actuating unit so that the footstool can move to the front of the seat.

In a particularly preferred embodiment, the rear rail is directly or indirectly fastened or rigidly connected to the seat support.

In a particularly preferred embodiment, the mechanical stretching device further comprises a traction link, the rear end of which is pivotally connected to the backrest support in front of the pivot connection point of the seat support to the backrest support, the front end of which is pivotally connected to the bearing assembly, preferably to the front end of the drive link in the bearing assembly, and the traction link is pivotally connected centrally to the seat support.

In this embodiment, by means of such a pivotal connection between the traction link, the seat support and the backrest support, in particular the pivotal connection of the traction link with the seat support in the middle, it is possible to mechanically advantageously drive the traction link downwards by means of the user's own weight when the user gets up and moves his/her centre of gravity forward from the backrest to the seat support, and thus to drive the backrest support pivotally connected to the rear end of the traction link to roll forward, so that the conversion of the seat unit from the lying position into the TV position is achieved in a simple, reliable and labor-saving manner.

Preferably, a long hole is arranged at the front end of the backrest bracket, a pin shaft is arranged at the rear end of the traction connecting rod, or a pin shaft is arranged at the front end of the backrest bracket, and a long hole is arranged at the rear end of the traction connecting rod, wherein the front end of the backrest bracket is connected with the rear end of the traction connecting rod through movable embedding of the pin shaft in the long hole.

The design mode provides a certain longitudinal degree of freedom for the relative movement between the backrest bracket and the traction connecting rod, prevents the clamping during the switching between the TV position and the lying position, and ensures the fluency of the relative movement between the backrest bracket and the traction connecting rod.

In a preferred embodiment, the components of the electric actuating unit, which are preferably designed as linear motor units, are connected to the front rail and the rear rail, respectively.

In this embodiment, the electric actuating unit is preferably a linear motor unit, which comprises a motor head, a motor rail connected to the motor head, and a motor slide which is slidable relative to the motor rail. One end of the electric actuating unit, such as a motor head, is pivotally connected to a front cross bar fixedly connected with the leg extension unit, and the other end of the electric actuating unit, such as a motor slider, is pivotally connected to a rear cross bar fixedly connected with the seat support, such that when the motor head moves longitudinally relative to the motor slider along the longitudinal axis of the motor slide rail, the front cross bar drives the leg extension unit to extend forward or retract backward, thereby changing the seat unit between the sitting position and the TV position. The opposite design is of course also possible, for example, by a motor slide of the electric actuating unit being pivotably connected to a front rail fixedly connected to the leg extension unit, and a motor head of the electric actuating unit being pivotably connected to a rear rail fixedly connected to the seat support.

In a preferred embodiment, the backrest support is tiltable back about a backrest pivot point when subjected to forces by a user pressing against the backrest by a rearward shift of the center of gravity and is connected to the seat support in such a way that the seat support can be raised during the tilting back of the backrest support, so that it can be shifted between the TV position and the lying position. For this purpose, it can be provided that the front end of the backrest support is connected to a pull rod of the tilting mechanism and is connected pivotably to the rear end of the seat support in the middle, and that the front end of the seat support opposite the rear end is connected pivotably to the leg extension unit. In this embodiment, the rear cross bar is fixedly connected directly to the seat support or indirectly to the seat support via an intermediate piece, so that the longitudinal drive force generated by the motor drive unit cannot be transmitted effectively from the rear cross bar to the backrest support, but is absorbed by the seat support, so that the power transmission chain from the electric actuating unit to the backrest support is cut off. When the user removes the force against the backrest by moving the centre of gravity forward, it can be depressed by the user and thereby flip the backrest support forward about the backrest pivot point, returning from the reclined position to the TV position.

In this case, the conversion of the seat unit between the TV position and the lying position can be accomplished without the aid of an electric actuating unit, simply by a rearward pressure applied by the user himself and a simple lifting action. In addition, because the rear cross rod is directly or indirectly fixedly connected with the seat support, the power connection with complex shape and more quantity between the rear cross rod and the traction connecting rod and between the traction connecting rod and the leg telescopic units in the prior art is omitted, so that the structure is simpler, fewer parts are needed, and the manufacturing cost is further reduced.

In a preferred embodiment, the tilting mechanism further comprises a spring element for tensioning the pull rod and the seat support relative to each other, said spring element being able to exert a downward pulling force on the pull rod when the backrest support is turned forward, in order to assist the backrest in restoring the sitting position; preferably, the point of action of the spring element on the pulling force of the pulling link is located behind the connection point of the pulling link with the seat support. The restoring force of the spring piece is utilized to assist the opposite movement of the seat support and the traction connecting rod, so that the back rest can be retracted more smoothly.

In an alternative embodiment, the tilting mechanism is further provided with a pneumatic spring connected to the backrest pivot point of the backrest support, which is configured to support the backrest support in a forward position about the backrest pivot point when the user is standing up, in order to support the backrest support in a return to the TV position as well as the sitting position.

In a preferred embodiment, the tilting mechanism further comprises a backrest locking mechanism, which is designed to prevent the backrest from tilting back in the sitting position and to form a stop for the maximum tilting of the backrest in the lying position. Thereby preventing the user from accidentally leaning back excessively, thereby ensuring the use safety.

The mechanical stretcher further comprises a base for supporting directly on the ground, and the supporting assembly is fixedly supported on the base. The base may be a circular bracket designed to be supported on the ground, to which a fixed bracket consisting of a set of parallel extending support rods is rotatably connected, so that the seat unit has a tilting, swinging/rocking function as well as a rotating function. Alternatively, the base may also be simply constructed as a set of parallel extending ground engaging brackets supported directly on the ground.

Preferably, the support assembly includes a swing base plate mounted on the base, a front swing lever, a rear swing lever, and a transmission connection lever, wherein a front end of the swing base plate is pivotably connected to a top end of the front swing lever, a rear end of the swing base plate is pivotably connected to a top end of the rear swing lever, and the transmission connection lever is pivotably connected to a lower end of the front swing lever and a lower end of the rear swing lever, respectively.

The invention further relates to a movable seating unit, comprising: a base for supporting on the ground, a seat portion above the base, a backrest behind the seat portion, a footrest in front of the seat portion, the aforementioned mechanical stretching device, and an electric actuating unit for switching the seat unit between the sitting position and the TV position. The movable seat unit may be a movable swing, a rocking chair, a sofa having a rocking or swinging function, or the like.

Drawings

Embodiments of the present invention are specifically described below with reference to the drawings.

FIG. 1a shows a perspective view of one embodiment of a mechanical stretcher of a seating unit in accordance with the present invention;

fig. 1b shows a perspective view of an alternative embodiment of a mechanical stretching device of a seating unit in accordance with the present invention;

fig. 2 shows a side view of the mechanical stretching device of the seat unit according to fig. 1a, wherein the seat unit is in a TV position;

FIG. 3a shows an isolated view of an electric actuation unit of a mechanical extension device of the seat unit according to FIG. 1 a;

FIG. 3b shows an alternative embodiment of a mechanical stretching device according to the present invention;

FIGS. 4a to 4c show perspective views of the seating unit of FIG. 1a in a sitting, TV and lying position, respectively;

FIG. 5a shows a side view of the back latch mechanism with the seat unit in the sitting position;

FIG. 5b shows a side view of the back latch mechanism with the seat unit in the TV position;

FIGS. 5c and 5d show partial views of the back latch mechanism when the leg extension unit is extended, respectively;

fig. 6a and 6b show a swing release state and a swing limit state of the swing limit mechanism, respectively;

FIG. 7 illustrates another alternative embodiment of a mechanical stretching device according to the present invention;

fig. 8a to 8c show a further alternative design of the mechanical stretching device according to the invention.

Detailed Description

An embodiment of a mechanical stretching device for a movable seating unit is first shown by way of example in fig. 1 a. The mechanical stretching device comprises: a base 1, a tilting mechanism 2, wherein the tilting mechanism comprises a seat bracket 3, a backrest bracket 4, a leg extension unit 5 with a footrest support plate 55, and an electric actuation unit 7.

The base 1 can be designed as a circular support 11 supported on the ground as shown in fig. 1a, to which a fixed support 12 consisting of a set of parallel extending support rods is rotatably connected.

Alternatively, in other embodiments, the base 1 may also be configured as a set of parallel extending ground engaging supports 13 supported directly on the ground as shown in fig. 1 b.

Above the base, in particular in the embodiment according to fig. 1a, a tilting mechanism 2 is fixedly connected to the fixing bracket 12. The tilting mechanism is arranged mirror-symmetrically on both the left and right sides with reference to the longitudinal direction of the seat unit, of which only half is shown and specifically explained here for the sake of simplicity. The tilting mechanism 2 includes a multi-link mechanism including a swing base plate 21, a front swing lever 22, a rear swing lever 23, and a transmission link 24, wherein the bottom of the swing base plate 21 is fixedly connected to a fixed bracket of a base, the front end of the top of the swing base plate 21 is pivotally connected to the top end of the front swing lever 22, the rear end of the top of the swing base plate 21 is pivotally connected to the top end of the rear swing lever 23, and the lower ends of the front swing lever 22 and the rear swing lever 23 are respectively pivotally connected to the transmission link 24 extending lengthwise.

As shown in fig. 2, the leg extension unit 5 is composed of a plurality of links pivotally connected to each other, wherein the rear end of the third foot lever 53 is pivotally connected to the seat bracket 3 at a first pivot point a, the front end of the third foot lever 53 is pivotally connected to the rear end of the second foot lever 52 through a second pivot point B, the rear end of the front link 26 is pivotally connected to the front end of the seat bracket 3 through a third pivot point C, the front end of the front link 26 is pivotally connected to the rear end of the first foot lever 51 through a fourth pivot point D, the front ends of the first foot lever 51 and the second foot lever 52 are respectively pivotally connected to the footrest support plate 55, and the second foot lever 52 is in turn pivotally connected to the front link 26 at a fifth pivot point E.

The rear end of the drive link 24 is pivotally connected to the lower end of an upwardly extending rear link 27, the top end of the rear link 27 being pivotally connected to a back pivot point M on the back bracket 4 via a back link 43. In this embodiment, the backrest support 4 is configured with a horizontal section 41 extending substantially horizontally and a vertical section 42 extending substantially vertically in the sitting position, the backrest pivot point M being located at the transition of the horizontal section and the vertical section. The seat support 3 is preferably pivotally connected to the middle of the horizontal section 41 of the backrest support 4, the rear end of the traction link 25 being pivotally connected to the backrest support 4 in front of a sixth pivot point F between the seat support 3 and the horizontal section 41, the front end of the traction link 25 being pivotally connected to the front end of the transmission link 24, the traction link 25 being pivotally connected to the seat support 3 in the middle through a seventh pivot point G.

In a preferred embodiment, a pin 44 is provided at the front end of the horizontal section 41 of the backrest bracket, and a slot 28 is provided at the rear end of the tension link 25, the pin 44 being movably engaged in the slot 28, so that the backrest bracket and the tension link are pivotally connected with a degree of freedom in the longitudinal direction. Alternatively, a reverse design, not shown in the figures, may be used, i.e., a long hole is provided at the front end of the horizontal section of the backrest bracket, a pin is provided at the rear end of the pulling link, and the front end of the horizontal section 41 of the backrest bracket is connected to the rear end of the pulling link 25 by a movable fit of the pin in the long hole.

As shown in fig. 3a, the seat unit has an electric actuating unit 7, which in this embodiment is a linear motor unit, comprising a motor head 71, a motor slide 72 connected to the motor head 71 and a motor slider 73 slidable relative to the motor slide 72, wherein the motor head 71 is pivotably connected to a front rail 74 fixedly connected to the front connection 26 of the leg extension unit 5, the motor slider 73 is pivotably connected to a rear rail 75, and the rear rail 75 is fixedly connected at both ends to the middle of the seat support 3 by means of intermediate connections 76, respectively. Thus, as the motor head 71 moves longitudinally back and forth along the motor slide 72 relative to the motor slider 73, the front cross bar 74 drives the leg extension unit 5 to extend forward or retract rearward via the front link 26.

When the leg extension unit 5 is fully extended, the motor head 71 reaches its forward limit position. Since the rear cross bar 75 is connected to the seat bracket 3, the longitudinal driving force is transmitted to the seat bracket without pushing the back bracket 4 to flip back about the back pivot point M. So that the seat unit can only be switched between the sitting position and the TV position under the drive of the electric actuating unit.

In a preferred embodiment as shown in fig. 3b, the tilting mechanism 2 further comprises a spring member 31 for tensioning the traction link 25 and the seat frame 3 to each other, said spring member being capable of exerting a downward pulling force on the traction link 25 when the backrest frame 4 is turned forwards, to assist the backrest in restoring the sitting position. Preferably, the point of action of the spring element on the pulling force of the pulling link 25 is located behind the seventh pivot point G between the pulling link 25 and the seat bracket 3).

The operation of the seat unit between the sitting position, the TV position and the lying position is described below with reference to fig. 4a to 4 c.

In the sitting position as shown in fig. 4a, the back support 4 is oriented substantially vertically, the seat support 3 is oriented substantially horizontally, the footrest support plate 55 is oriented substantially vertically and the leg extension unit 5 is fully stowed under the seat support 3; in the TV position shown in fig. 4b, the leg extension unit 5 is fully extended forward, the relative positions of the seat support 3 and the backrest support 4 remain substantially unchanged; in the lying position as shown in fig. 4c, the leg extension unit 5 remains fully extended forward and the back support 4 is fully reclined.

When the motor head 71 is operated forward, the position of the seat support 3 is kept basically unchanged in the longitudinal direction due to the gravity action of a user, the motor head 71 moves forward along the motor sliding rail 72 relative to the motor sliding block 73, so that the distance between the motor head 71 and the motor sliding block 73 is increased, the front cross bar 74 drives the front connecting piece 26 to rise forward, and the leg telescopic unit is fully unfolded from the folded sitting position shown in fig. 4a to the TV position shown in fig. 4 b. Starting from the TV position, when the user leans backwards on the backrest with force, the backrest support 4 is tilted backwards around the backrest pivot point M by the backward pressure, which in turn brings about the upward tilting of the traction link 25, at the same time as the rear end of the seat support 3, which is pivotally connected in the middle of the horizontal section 41 of the backrest support 4, is brought up slightly, whereas the position of the seat support 3 and the leg telescopic unit 5 remains substantially unchanged. The lying position shown in fig. 4c is reached when the back rest bracket 4 is tilted backward to the maximum extent.

When the user gets up, the pressure applied to the back rest bracket 4 is removed, so that the back rest bracket 4 automatically pivots forward about the back rest pivot point M under the action of the traction link 25, thereby returning from the lying position to the TV position. From the TV position, if the motor head 71 is reversely operated, the motor head 71 is moved toward the motor slider 9 along the motor slide rail 10, so that the distance between the motor head 71 and the motor slider 9 is shortened, and the leg extension unit 5 is retracted to the sitting position by the pulling link 25.

In a preferred embodiment, the backrest support 4 is provided with a backrest locking mechanism 8. As shown in fig. 5a to 5d, the backrest latch mechanism 8 comprises a slotted link 81, one end of which slotted link 81 is pivotably connected to the horizontal section 41 of the backrest support 4, the other end is provided with a backrest link slot 82, a longitudinally extending mounting member 83 is provided with a latch member 84 at one end, the latch member 84 being slidably inserted into the backrest link slot 82 of the slotted link 81, and the other end of the mounting member 83 is pivotably connected to the third leg 53. As shown in fig. 5a, in the sitting position the leg extension unit 5 is fully retracted, the mounting member 83 with its latch member 84 at one end abuts against the lowermost part of the backrest connector chute 82 of the chute connector 81, thus preventing the backrest support 4 from tilting backwards in the sitting position. As shown in fig. 5b and 5c, when the leg extension and retraction unit 5 is unfolded, the mounting member 83 is moved forward by the leg extension and retraction unit, so that the latch member 84 at the end thereof moves forward in the back link sliding groove 82 and no longer abuts against the lowermost part of the back link sliding groove 82, thereby allowing the back bracket 4 to tilt backward. As the backrest bracket 4 is tilted backwards, the slide link 81 moves upwards until the catch 84 of the mounting element 83 again abuts against the lowermost part of the backrest link slide 82, whereby the maximum tilting of the backrest bracket is reached as shown in fig. 5 d.

In a preferred embodiment, as shown in fig. 6a and 6b, the mechanical stretching device has a pivot stop 6, which comprises a first stop 61, a second stop 63 and a slide stop 65. The first limiting member 61 is pivotally connected to the transmission connecting rod 24 at the middle part thereof, a second limiting bushing 62 is provided at the front end of the first limiting member 61, the rear end of the first limiting member 61 is pivotally connected to the front end of the second limiting member 63, and a second limiting bushing 64 is provided at the rear end of the second limiting member. The chute limiter 65 is fixedly connected to the drive connection rod 24 and extends upwardly from the drive connection rod into a section with a swing limit chute 66, the second limit bushing 64 being movably fitted in the swing limit chute 66. The swing limit mechanism 6 is capable of switching between a swing release state and a swing limit state. In the swing release state as shown in fig. 6a, the tilting mechanism 2 is in a sitting position, the first and second limit bushings are out of contact with both the front swing lever 22 and the rear swing lever 23, allowing a pivoting movement of the front and rear swing levers back and forth, so that the tilting mechanism can swing back and forth relative to the base. In the swing limit state as shown in fig. 6b, the leg extension and retraction unit is extended, the second limit bushing 62 and the second limit bushing 64 are moved away from each other in opposite directions, wherein the second limit bushing 62 is moved forward toward the front swing lever 22, and the second limit bushing 64 is moved backward toward the rear swing lever 23 in the swing limit chute 66. When the seat unit is moved into the lying position, the leg extension unit is fully extended, with the first limit bushing abutting against the inside of the front swing lever 22 and the second limit bushing abutting against the inside of the rear swing lever 23, thereby preventing the pivoting of the front and rear swing levers 15, 16 so that the reclining mechanism can no longer swing back and forth relative to the base.

In an alternative design as shown in fig. 7, the rear connection 27 and the backrest connection 43 can be replaced by pneumatic springs. A pneumatic spring 42 is provided between the back bracket 4 and the rear end of the drive link 24 at the back pivot point M. The pneumatic spring 42 is designed to hold the back rest in a reclined position by the force of gravity of the user when the user leans back against the back rest from the TV position, and to return the back rest to the TV position when the user is standing up.

In an alternative as shown in fig. 8a to 8c, the rocking substrate 29 is used instead of the rocking substrate in the tilting mechanism described above. The swing substrate 29 is fixed at its bottom to the base 1 having a swing function. Wherein fig. 8a, 8b and 8c show the seating unit in a sitting position, TV position and lying position, respectively. The remaining technical features that are identical to the embodiments of fig. 1a to 7 are not described in detail here.

List of reference numerals

1. Base seat

11. Round support

12. Fixing support

13. Ground contact support

2. Tilting mechanism

21. Swing substrate

22. Front swinging rod

23. Rear swing lever

24. Transmission connecting rod

25. Traction connecting rod

26. Front connecting piece

27. Rear connecting piece

28. Long hole

29. Rocking the substrate

3. Seat support

31. Spring element

4. Backrest support

41. Horizontal section

42. Vertical section

43. Backrest connecting piece

44. Pin shaft

5. Leg telescopic unit

51. First foot bar

52. Second foot bar

53. Third foot bar

55. Foot stool support plate

6. Swing limiting mechanism

61. First limiting piece

62. First limiting bushing

63. Second limiting piece

64. Second limiting bushing

65. Chute limiting piece

66. Swing limiting chute

7. Electric actuating unit

71. Motor head

72. Motor slide rail

73. Motor sliding block

74. Front cross bar

75. Rear cross bar

76. Intermediate connecting piece

8. Backrest locking mechanism

81. Chute connecting piece

82. Backrest connecting piece chute

83. Mounting member

84. Locking piece

9. Pneumatic spring

A first pivot point

B second pivot point

C third pivot point

D fourth pivot point

E fifth pivot point

F sixth pivot point

G seventh pivot point

M backrest pivot point.

Claims (14)

1. A mechanical stretcher for a movable seating unit, comprising:

for supporting the assembly directly or indirectly on the ground;

a tilting mechanism (2) comprising a multi-link mechanism and for attachment to a seat portion, a backrest and a footrest of the seat unit, configured to enable sequential or reverse sequential shifting of the seat unit from a sitting position in which the footrest is stowed under the seat portion to a TV position to a lying position; in the TV position, the footrest is located in front of the seat portion, the relative position between the seat portion and the backrest remaining the same as in the sitting position; in the lying position, the relative position between the footstool and the seat part remains the same as in the TV position, the angle between the seat part and the backrest increasing relative to in the TV position, wherein the tilting mechanism (2) comprises a leg extension unit (5) for mounting the footstool, a seat bracket (3) for mounting the seat part and a backrest bracket (4) for mounting the backrest, which are pivotally connected in sequence;

wherein the tilting mechanism (2) is configured such that a change of the seat unit between the sitting position and the TV position can be achieved by means of the electric actuating unit (7), whereas a change of the seat unit between the TV position and the lying position can only be achieved by means of a non-electric actuating, wherein the backrest support (4) can be flipped backwards about the backrest pivot point (M) when subjected to a force by a user pressing against the backrest by a rearward movement of the center of gravity and is connected to the seat support (3) such that the seat support (3) can be raised during a backward flipping of the backrest support (4) and can be depressed by the user and thereby flip the backrest support (4) forwards about the backrest pivot point (M) when the user removes the force pressing against the backrest by a forward movement of the center of gravity.

2. Mechanical stretching device according to claim 1, wherein the tilting mechanism (2) is configured for swinging or rocking the seat unit, allowing the seat unit to swing or rock back and forth with respect to the ground in the sitting position, whereas not allowing the seat unit to swing or rock back and forth with respect to the ground in the TV position and the lying position.

3. The mechanical stretcher according to claim 1 wherein the support assembly is adapted to provide a rocking or swinging function for the seating unit.

4. The mechanical stretching apparatus according to claim 1, wherein a front cross bar (74) is connected to the leg extension unit (5), and a rear cross bar (75) is fixedly connected to the seat support (3), wherein the front cross bar (74) can be moved forward relative to the rear cross bar (75) by the electric actuating unit (7) to move the footrest in front of the seat.

5. Mechanical stretching device according to claim 4, wherein the rear cross-bar (75) is directly or indirectly fixed or rigidly connected to the seat support (3).

6. The mechanical stretching device according to claim 1, further comprising a pulling link (25) with a rear end pivotally connected to the back support (4) in front of the pivotal connection of the seat support (3) to the back support (4) and a front end pivotally connected to the support assembly and pivotally connected to the seat support (3) in the middle.

7. The mechanical stretching device according to claim 4, wherein the component parts of the electric actuation unit are connected to a front crossbar (74) and a rear crossbar (75), respectively.

8. The mechanical stretching device according to claim 7, wherein the electric actuation unit is designed as a linear motor unit.

9. The mechanical stretching device according to claim 8, wherein the tilting mechanism (2) further comprises a spring member for tensioning the traction link (25) and the seat support (3) to each other, said spring member being capable of exerting a downward pulling force on the traction link (25) when the backrest support (4) is turned forward, to assist the backrest in restoring the sitting position.

10. Mechanical stretching device according to claim 9, wherein the point of action of the spring element on the pulling rod (25) is located behind the point of connection of the pulling rod (25) to the seat bracket (3).

11. A mechanical stretching device according to claim 1, wherein the tilting mechanism (2) is further provided with a pneumatic spring (9) connected to the back pivot point (M) of the back rest bracket (4), the pneumatic spring (9) being configured to support the back rest bracket (4) to be flipped forward around the back pivot point (M) when the user gets up.

12. Mechanical stretching device according to claim 1, wherein the tilting mechanism (2) further comprises a backrest latch mechanism (8), the backrest latch mechanism (8) being designed to prevent the backrest from tilting backwards in the sitting position and to constitute a stop for the maximum tilting degree of the backrest in the lying position.

13. A mechanical stretching device according to claim 1, further comprising a base (1) for supporting directly on the ground, the support assembly being fixedly supported on the base.

14. A movable seating unit, the seating unit comprising: base (1) for supporting on the ground, a seat portion above the base (1), a backrest behind the seat portion, a footrest in front of the seat portion, a mechanical stretching device according to any one of the preceding claims and an electric actuation unit (7) for switching the seating unit between the sitting position and the TV position.