DE2352564A1 - ADJUSTABLE ARMCHAIR - Google Patents

Description

8 MUNICH 86, DEN

PO Box 860 820

MÖHLSTRASSE 22, CALL NUMBER 98 3921/22

Peter Stewart Fletcher

4-17 North Railroad Avenue

Boynton Beach, Florida 554-55 / V.St.A.

Adjustable armchair

The invention relates to an adjustable armchair with a headrest that can be adjusted by moving the backrest, which is associated with an adjusting device with a pivotable drive lever on the backrest, which is associated with a is connected to the chair frame pivotably mounted operating joint and connected to one with the headrest Connecting hinge is coupled so that a pivoting movement of the drive lever on the backrest of the headrest moved between a retracted and a support position.

In such an armchair, the headrest is on the The backrest is attached and can also be moved relative to a stationary chair frame when it is moved. This movement is done by an actuator that sits between the backrest, the chair frame and a holder for the headrest is provided on the backrest, so that the headrest automatically from a retracted position behind the backrest is brought into a support position when the armchair from a upright position is inclined.

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ORIGINAL INSPECTED

An adjustable armchair of this type can also have a Movement is done in two phases of movement for three different positions, with either the seat and the backrest are rigidly connected to one another or the seat and the backrest can be pivoted relative to one another. Such a chair has a first movement phase with a backward movement of the seat and the backrest for a medium inclination, whereby also a movement of a footrest to a raised position take place can. This first phase of movement moves the chair from its upright sitting position to a medium inclined position, which has also become known as the learning position. In a second movement phase then takes place a pivoting movement of the backrest about a center of rotation, so that the The backrest is inclined more strongly. At the end of this second phase of movement, the chair has reached its fully inclined position.

Such an armchair can also be used as a double motion chair be referred to as an extendable headrest. A headrest for such a chair is for example through U.S. Patent 3,14-0,117. She works with one Operating joint with which a joint mechanism for the headrest is moved, which removes the headrest from its retracted position Brings position behind the backrest into a support position when the backrest is moved in the first phase of movement. The actuating joint moves around a pivot point that is coaxial with the pivot point of the backrest at the end of the first movement phase. During the first phase of movement, the backrest is shifted to act on the Operating joint exploited so that it can move a holder for the headrest. During the second movement phase, however, there is no further actuation of the headrest. since the pivot center of the operating joint and the pivot center of the backrest are coaxial with one another. The headrest is therefore in the second phase of movement

the position it had once assumed in relation to the backrest held.

The object of the invention is to provide the known arrangement, to be improved so that an easier and more versatile application is possible and in particular the position of the headrest can be adjusted during the second movement phase, so that an adjustment can be made with a more compact joint mechanism to the shape of an armchair that is primarily designed from an aesthetic point of view. Further it should be possible to change the amount of movement of the headrest during the first movement phase within wide limits.

In connection with the solution of this problem it has been shown that the pivot center of the actuating joint does not have to coincide with the pivot center of the backrest during the second movement phase. From this it resulted a construction with some special advantages, which can be achieved while maintaining the advantages of the known arrangement.

The above-mentioned object is achieved with an armchair of the type mentioned in that the connection point of the drive lever and operating joint is arranged during a phase of movement from a medium inclination to a strong inclination at a point remote from the center of rotation of the backrest, which is the pivot point of the drive lever and ■ is associated with the length of its lever arms so that the other end of the connecting joint remains substantially stationary relative to the backrest.

The invention provides an armchair in which essentially no movement of the headrest occurs during the second movement phase, but a certain amount of adjustment the headrest can be provided. It can

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some change in the relative position of the headrest opposite of the backrest during the second movement phase. For example, when the backrest is moved into its fully inclined position, an adjustment of the Position of the headrest. This can be beneficial, for example, when due to different loads of the armchair whose upholstery experiences corresponding different arrangements that require an adjustment of the headrest position. Furthermore, by an arrangement According to the invention, a more versatile outer appearance of an armchair can be realized, as a total compact joint mechanism is provided, the amounts of movement of which are within the most varied due to the profile Armchair shapes fall in the given space. During the first phase of movement there is still ^ any desired shift the headrest possible.

As will be described below, the invention can also be used for armchairs that have a fixed assignment of seat and backrest to each other.

The pivot point of the chair frame is preferably arranged on a line which bisects the angle formed by a first line between the location of the actuation pivot point in the middle inclined position and the location of the center of rotation of the backrest during the second movement phase and a second line between the Location of the center of rotation - point of the backrest during the second phase of movement <^; and the location of the operating pivot point is formed in the steeply inclined position. The location of the pivot point for the chair frame automatically ensures in this way that the other end of the connecting joint remains practically stationary during the second phase of movement.

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The pivot point of the drive lever should be arranged on a line which is the median perpendicular of a line which runs between the location of the operating pivot point in the upright The seat position and the location of a point on the back line that is close to the actuation pivot point, when the chair is in the middle tilt position. The change of the point along this central perpendicular, at which the pivot point of the drive lever is arranged, enables a change in the lever arrangement acting on the headrest and thus their amount of movement during the first movement phase.

If the connecting joint and the drive lever during the remain practically stationary in the second movement phase, undesired movement of the headrest during the transition can occur from the television position to the strongly inclined position can be avoided.

The connecting joint and the drive lever arm are preferably located to the associated pivot point during the second movement phase on a line. Form the joint and the lever arm in this way a support that holds the headrest in place.

The position of the headrest can be changed during the second movement phase by changing the location of the frame pivot point a theoretically exact position.

Preferably, the drive lever has two arms that of his Pivot point go out perpendicular to each other, while in the seated position of the chair the drive lever pivot point below the actuation pivot point and both behind the drive lever pivot point lie. This arrangement enables effective translation of the generally horizontal movement of the seat into an upward movement of the headrest during the first movement phase.

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A Ausführungsb ei game of the invention is shown below Hand of the figures described. Show it:

Fig. 1 is a side view of an armchair according to the invention, the frame and upholstery shown in dashed lines are, while the hinge mechanisms are shown in solid lines,

Fig. 2 is a rear view of the armchair shown in Fig. 1,

FIGS. JA, B and C are partial side views of that shown in FIG Articulated mechanism for various operating positions, with a hinge arrangement rigidly connected to the backrest in FIG. 3A and the headrest in FIG. 3B actuating hinge assembly with a Terbindungspunkt and in Fig. 3C a hinge assembly for the Seat and backrest are shown during the first phase of movement,

Figures 4A, B and C are schematic representations of the chair joint for coordinating the movement of the backrest and the headrest, FIG. 4-A showing the position of the Joints in the upright position, Fig. 4-B the position of the joints in the television position and Fig. 4-C the position of the joints in the fully reclined position represent, and

5 shows a geometric diagram of the functional relationships the "joint construction.

In Fig. 1, an armchair 10 is shown, which has a base or arm frame 12, which the holder for the movable Elements forms. The movable elements comprise one formed by a seat 16 and a backrest 18 Unit 14-, a footrest 20 and a headrest 22. In known Thus, the unit 14 is secured within the arm frame 12 by a mechanism that is a hinge device 24- forms. There are two pairs of joints 24- provided, where-

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at ^ on each side of the chair 10 one is arranged. the Hinges include a plurality of hinge members that hold the seat 16 and back 18 to the frame and the footrest 20 on the unit 14 and the headrest 22 on the Hold backrest 18.

The functional details of the seat unit 14 and Mechanisms connecting the footrest are known, for example, from US Pat. No. 3,393,007. This joint meehanism is therefore only briefly explained below. An armrest 26 forms an anchorage for the joint 24 and is rigidly connected to the base frame 12. The seat is on the armrest by a front guide joint 28 on a Swivel mounting 28a held, the ^ joint 28 is with a Sitzhaiterung 30 connected via a seat lever 32, which is attached to the seat bracket is connected by a pivot point 32b and to the guide joint 28 by a pivot point 28b is. The seat holder 30 is connected to a frame that carries the seat .16. The seat bracket 30 is with the backrest pivotally connected at a pivot point 34-. The for the part of the joint mechanism 24 provided for the backrest is a backrest holder in the illustrated embodiment 36, which consists of several pieces of metal rigidly connected to one another. As can be seen from Fig. 3A, a long, boomerang-shaped strip 38, a second, smaller boomerang-shaped Strip 40, connected to the first by rivets 42, and one rigidly connected to the strip 38 by rivets 43 Seat projection is provided which protrudes in the Vforward direction and with the seat bracket 30 at the pivot point 34 between The seat and backrest are pivotally connected. The strips 38 and 40 are formed so that between them of the From the front or the rear, there is a distance that is also shown in FIG. 2. The frame the backrest 18 is rigid with the backrest bracket

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56 connected by bolts 45, for example.

In FIG. 30 , a rear guide joint 46 is shown which is fastened to the armrest 26 at a pivot point 46a and is connected to the backrest holder 56 on the first strip 58 at a pivot point B. During the first phase of movement, the unit 14 moves backwards and is inclined slightly by the combined action of the front guide joint 28 at pivot point 28a and the rear guide joint 46 at pivot point 46b. At the same time, the headrest 22 is brought from the retracted position (FIG. 1) into a support position, as will be described below. In addition, the footrest 20 is extended by a hinge assembly 48. Here, an actuating joint 50, which is pivotally attached to the armrest 26 at a pivot point 50a, moves and moves the joint arrangement 48 via the pivot point 50b Backward movement of the seat holder 50 in the first movement phase is pushed forward and opened so that the footrest 20 is brought into its raised position. This arrangement is known from US Pat. No. 5,092,416.

The seat lever 52 has in conjunction with one on the Annauflage 26 attached pin 52 has a subsequent function. The front one The end of the seat lever 52 is arranged under the pin 52 until the first movement phase has ended. This prevents the seat 16 from moving upwards in this phase of movement will. When the first phase of movement is over, the front end of the seat lever 52 is behind the pin 52, so that the chair can then be brought into its second phase of movement. ·

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At the end of the first movement phase, the rear guide joint 46 acts on a stop 46e and continues to move the backrest 18 is connected to a pivoting movement about the pivot point B. The lower end of the backrest bracket 36 is with a connecting hinge 53 on one Pivot 53a pivotally connected, this joint is again pivotable with the seat lever 32 at a point 53b tied together. Since the seat lever 32 was moved backwards relative to the pin 52 during the first movement phase, causes the force transmitted from the backrest 18 via the connection joint 52 causes the seat lever 32 to rotate clockwise about the pivot point 28b, whereby the front part of the seat 16 is raised. The stop 32a on the seat lever 32 and a groove 30a on the seat bracket 30 are separated from each other separated during the second movement phase until the stop 32a forms a groove 53c on the connecting joint 53 hits when the chair has reached its fully reclined position. The position remains during the second movement phase of the footrest 20 relative to the seat 16, since the actuating joint 50 does not have any substantial during its upward movement Movement of the holding joint 48 causes. As described is the headrest attachment and its operating joint so provided and designed that the headrest 22 either does not perform any movement relative to the backrest during the second movement phase or only one experiences such movement that is required to adjust the headrest relative to the backrest, with «however the support function is retained when the unit consisting of the headrest and backrest is in the fully inclined position is moved.

With reference to FIGS. 1, 3B and 3C, the bracket is shown below and actuation of the headrest of an inventive Described armchair. The headrest 22 is on a bracket 54, which in turn is attached to the first boomerang

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shaped strip 38 of the holder 36 for the backrest with two! guide joints 56 and 58 is attached. The joint 56 is at the lower end of the holder 5 ^ & n · a point 56a and is suspended from the strip 58 at a point 56b. The hinge 58 is suspended at the upper end of the strip 54 at a pivot point 58a and at the upper end of the strip 38 at a pivot point 58b. The hinges 54-56 and 58 form the three articulated hinges of a four-part headrest hinge assembly in which the strip 38 on the seat back is the stationary member. The one in Pig. 1, 3B and 3C corresponds to the rest position for the headrest 22. When the joints 56 and 58 are pivoted upwards about the pivot points 56b and 58b, the headrest 22 moves backwards out of a recess in the rear of the backrest 18 is provided. Then the headrest is brought up into a support position. This is best done by comparing the Pig. 4-A and 4-B can be seen. A spring 60 is disposed between the pivot point 58b and a pin 62 on the lower arm 56 and balances the forces generated by the weight of the headrest 22, which are maximum when the headrest 22 is in the middle of its movement from the rest position in the Recess of the backrest 18 is in the support position. As will be described later, the four-part hinge arrangement of the headrest 22 is actuated via a connecting hinge 64.

In the following, the Pig. 1 and 3B a preferred one Described embodiment of an actuating mechanism for a headrest in an armchair according to the invention. On the hand of the pig. 5 the theoretical criteria are explained, which are necessary for the construction and the construction of such a Mechanism are authoritative. The joint arrangement shown in the other figures can also be used as an illustration of the invention.

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The BetatigungsmechanismuB 66 for the headrest is _i on the armrest 26 and the "mount 56 disposed between a rigid support 26a for the back rest so that it can be actuated by the relative movement between the backrest 18 and the stationary base frame 12 during the first movement phase of the Jiehnstuhls A drive lever 68 is arranged at a pivot point L which is carried by the lower boomerang-shaped strip 40 of the bracket 36. The drive lever 68 has two arms which extend from the pivot point L, one of these arms is with an operating joint 70 at an operating pivot point A is connected at one end of the joint 70, the other end of this joint is connected to the bracket 26a at the pivot point P of the base frame. The other arm of the drive lever 68 is connected at the pivot point D to the connecting joint 64 for the headrest actuation. 3B and from a comparison of FIGS. 4A and 4B it can be seen that During the first movement phase of the armchair, the relative movement of the holder 36 with respect to the stationary frame 12 and thus the armrest. 26 generates a rotation of the drive lever 68, which results in a force transmission and a movement of the headrest 22 via the connecting joint 64. As previously stated, the connecting hinge 64 moves upward and acts on lower and upper headrest guide joints 56 and 58 to rotate counterclockwise, causing the headrest 22 to move from the retracted position of FIGS. 1 and 4A to the extended position Fig. 4B arrives. The joint 64 is aligned with the arm of the drive lever, which lies between the drive pivot point and the drive lever pivot point, so that there is a locking effect by which the headrest is firmly fixed in its extended position.

In contrast to the subject matter of US Pat. No. 3,140,117

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falls the pivot point P of the actuating mechanism 66 for the headrest on the chair 10 not with the center of rotation ' the backrest together during the second movement phase. In the known arrangement, the actuating mechanism for the headrest come into effect when the pivot point with the center of rotation of the backrest during the second phase of movement coincides, creating a relative Operating movement is only possible during the first movement phase and no movement during the second movement phase he follows. In an armchair according to the invention, however, other positions are provided in which the actuation pivot point is arranged during the second movement phase, so that the upper end and thus the entire joint 64 as well as the drive lever 68 remain practically stationary relative to the backrest during this movement phase and that Link joint in line with the arm of the lever. 68 remains between the drive pivot point and the drive lever pivot point. This way there will be no or one only a small actuation movement is generated for the headrest, or only a very small movement is advantageously provided, which maintains a predetermined degree of support on the headrest during the second phase of movement. the The backrest 18 of the chair 10 pivots during the second movement phase about the pivot point B at the upper end of the rear one Guide joint 46. This acts on the stop 46c of the armrest 26 at the end of the first movement phase, see above that it remains stationary during the second phase of movement. The backrest 18 and also its holder 56 pivot around the then stationary pivot point B during the second movement phase. As can be seen from a comparison of FIGS. 4A, 4B and 4C, however, the pivot point B for the seat back and the pivot point P for the operating mechanism fall 66 of the headrest in the television position according to FIG. 4B or in the fully inclined position according to FIG. 4C

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not together, so that this is also not the case during the second movement phase. These pivot points are intentionally arranged so that they are spaced from one another during the second phase of movement. As can also be seen from FIGS. 4B and 40, there is little or no movement of the headrest relative to the backrest during the second movement phase. The one in Jig. ^{The joints shown in FIGS. 2} IA, 4B and 40 are tilted counterclockwise (forwards) by a certain amount in relation to the horizontal position shown in FIG. However, this is only provided because the three figures are arranged on the same sheet and a constant scale is given for all drawings.

The following is an explanation of the specific geometric Criteria that must be met so that the actuating mechanism for the head restraint works in the desired manner. The criteria to be described enable forward movement of the headrest by the actuating mechanism 66 from a retracted to a support position during the first movement phase and then maintaining the position the headrest in the support position during the second movement phase with or without minor adjustment movements of the relative position of the headrest to the backrest. This explanation is used in FIG. 5, which in connection with the already should be considered.

In Fig. 5, the geometry of the actuating mechanism is schematically 66, this is tilted in the same way as in FIGS. 4A, 4B and 40. For orientation, reference is made to the pointed rear guide joint 46, which is attached by the pivot point 46a to the frame of the chair and from its position in the upright sitting position of the chair, which is shown in solid lines, into its position

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moved for the television position, which is shown in dashed lines. This position is determined by the stop 46c. At the upper end of the rear guide joint 46 the pivot point B for the backrest is provided, which is designated with B_ for the seated position and with Bp for the position of the backrest during the second phase of movement from the television position to the fully inclined position. The dashed lines extending upward from points B and Bp to points X ₅ , X ^ -y and X _R correspond to a single arbitrary line in the seat back 18 from pivot point B via an arbitrary point X further upwards, the position this line for the sitting position of the chair (point X ₁ J, for the television position of the

Chair (point Χφ _ν ) and for the fully inclined position of the chair (point X _R ) is shown. The indices used correspond to the different places of point X for different positions of the chair. For example, D_ is the location of the drive pivot point D in the seated position of the chair and Ώ ^ γ the location of this pivot point for the television position of the chair. A change in this notation is provided for the identification of the positions of the actuation pivot point A. This is labeled A for the sitting position and An ™ · for the television position. A third position is marked with Α ¹ ™ «.«, This designation has a "special meaning. It marks the location of pivot point A, projected onto the backrest when the chair is in its television position and when the backrest is then through the first The designation A'm-tr _s is therefore a real point in space - which is determined by a point on the backrest, which is located near the pivot point A when the chair is in the Eemsehposition and the backrest is in the upright sitting position.

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The backrest (and thus the line BX between points B and X) rotates around a fixed center of rotation Bp over an angle Θ. during the second movement phase. «Teder. Point X of the backrest can cover one and only one arcuate path during such a movement. This arc is defined as the arc in Pig running between points Χ ^ γ and X _R relative to point B ^. 5 shown. If the actuation pivot point A is not to produce any movement of the actuation mechanism 66 during the second movement phase, it must move with the backrest during this phase and describe an arc with the angle θ with respect to point B. If a suitable point is selected for the actuation pivot point A and its position is determined relative to the backrest in the television position, its position for the fully inclined position is also known, ie an arc around the pivot point B over an angle θ is described and determines the position of the point. This angle can also be referred to as the -ΑφγΒοΑτ angle, or as the angle between the lines A ^ Bg and BgA ^. The bisector of this angle is designated as the P-line and is located on the fixed chair frame.The pivot point P must be arranged on this line if there is no relative movement of the headrest with respect to the backrest when moving from the television position to the fully inclined position . The pivot point P can be set on the P line within practical limits to be described. The greater the distance between the pivot point P and the pivot point B, the greater the difference between the path Β _ΛΤ) «of the actuation pivot point A during the second movement phase in which the pivot point B is coaxial with the pivot point P (a Arc with pivot point B as the center) and the actual path A, _RG (an arc with pivot point P as the center). In • an armchair according to the invention, this small ab-

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In most cases, there was little or no movement of the headrest during the second movement phase between the two arches between their interfaces at points A _R and λ ^ γ. Of greater importance, however, is not this slight movement, but the fact that the basic pivot point P of an armchair can be located in front of the position of the pivot point B for the backrest during the second phase of movement and thus before the position described in US Pat ΊΊ7 is in the position shown. It follows that an armchair can be realized which has a much shorter fixed base dimension, since it is not necessary to move a base pivot point as far back as is the case with the known arrangement. Those skilled in the art will recognize that the pivot point B for the backrest may be at some point beyond the actual dimension of the base frame when the chair is in its upright position, as the rear articulation may in some cases be arranged to lie moved behind the rear end of the frame.

The position of the pivot point L of the drive lever basically depends on the drive effect desired for it during the first movement phase. If, for example, a quick initial movement is desired, the positions of the arms of the drive lever relative to the remaining joints are adjusted by a suitable choice of the position of the pivot point L. If a large movement of the drive pivot point D is required relative to movement of the drive lever pivot point L, the relative lengths of the arms of the drive lever are adjusted accordingly. There is a large area available for the selection of the position of the pivot point L of the drive lever, ijedoc * ¹ the geometry can be precisely determined by choosing a bisecting line, which is referred to as the L-line.

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The actuation pivot point A moves up. an arc relative to the backrest around the Schttfenkpunkt L of the drive. hebeis, with this arc running through the point A ^ -y (the position of the pivot point A in the TV position) "It has already been described in what way the point A'm" _{s shown in FIG.} The backrest arises when the point Äm "is projected relative to the backrest onto an adjacent point on the backrest and this is then brought back into its upright sitting position. The part of the drive lever 68 between the points A and L must always meet the condition that when the lever 68 moves around the point L, the actuating pivot point A can pass through the point A'm " _{g of} the backrest. Furthermore, the actuating pivot point A must lie in the upright sitting position at the point A_ on the arc which is traversed by the actuating joint 70 of the headrest. Therefore, the position of the drive lever pivot point L on the headrest bracket must be such that the position L in the upright sitting position is the same distance from the points ^ * TV-S ^{un <} ^ "^ s ^ at. It follows that the drive lever pivot point L in the upright position The seated position of the armchair must lie on the mid-vertical of the line that runs between A _s and A'm-y- "and is referred to below as the L-line.. ■ _.,

I ¹ Ur nede selected position of the point A_ along the arc _RC Ai, the lever arm of the drive lever 68 AL can be changed by changing the pivot point L is moved on the L-line and is thus set a larger or smaller mechanical advantage. Similarly, the position of the point A_ along the arc A.ort can be selected at any suitable point in order to achieve the respectively desired acceleration during the first movement phase. Thus, a large range of headrest control is available within the criteria described above.

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However, some limit values must also be observed. The basic pivot point P cannot be moved so far forward along the P line that the angle PAL always has a value of 180, since in this state there is no torque on the drive lever 68 via the joint 70 is exercised. This angle should be significantly less than 180 °. Furthermore, the pivot point P cannot be moved so far forward that the joint 70 rotates the drive lever 68 in the opposite direction to the desired. Furthermore, all arrangements must of course be avoided in which parts that are pivotably connected to one another are in dead center position or in a row. Great differences in the curvature of two arcs connecting points A ^ y and A _R and in Pig. 5 _{labeled A ARC} and B _ARG should be avoided in order to keep the movement of the headrest minimal during the second movement phase, with the exception of those cases in which such movement is desired.

In addition to the extensive design options and the special advantages described above, the invention offers further advantages with regard to the possibility of adjusting the headrest position during the second movement phase. While the pivot point P must be located on the P-line, there may be an intentional slight deviation from it theoretically precise geometrical position for such a Degrees can be introduced through which an adjustment of the head restraint does not differ significantly from those described above geometric criteria is possible. Such an adjustment movement may be desirable to a predetermined Maintain the degree of head rest during the second movement phase, as the body is lying on the Armchair in the television position and in the fully reclined position is in different arrangements relative to the support surface. In the television position, the body remains

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for example, relatively upright while in the full inclined position is more horizontal and thereby the The pressure on the headrest is stronger. This can compression of the headrest padding may occur so that the head is actually lower than desired. To correct this, a slight lifting of the headrest relative to the backrest can be beneficial when the seat is moved to the fully reclined position will. In other palls the opposite effect can occur and the increased stress appears on the backrest and not on the headrest. An armchair according to the invention enables the appropriate settings to maintain the given support properties of the headrest,

The invention provides overall greater versatility for satisfactory control of the headrest movement possible, this is provided by a hinge arrangement that is compact and easy to operate while at the same time an adaptation to the various external shapes of an armchair is given.

In the above description of the exemplary embodiment, separate seat and backrest elements have been used assuming »The invention is in the same way also on such armchairs can be used in which the seat and the backrest form a common unit. In such Chairs should be understood under the pivot point for the backrest or the center of rotation for the backrest, a pivot point or a center of rotation around the the unit formed from the seat and backrest is moved in the second movement phase. Under a stationary The basic frame of the armchair should also be understood as a frame that is not stationary on a punching-up ■

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but can be moved on it, as is the case with rocking chairs.

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Claims (7)

Expectations ^f ' Λ J Adjustable armchair with headrest that can be adjusted by moving the backrest, to which an adjustment device is assigned to a drive lever that can be pivoted on the backrest *, that is connected to an actuating joint that is pivotably attached to the chair frame and that is coupled to a connecting joint that is connected to the headrest, so that a pivoting movement of the drive lever on the backrest moves the headrest between a retracted and a support position, characterized in that the connection point (A) of the drive lever (68) and the actuating joint (70) during a movement phase from a medium inclination to a strong one Inclination (lig. 4B and 4G) is arranged at a point of rotation away from the center of rotation (B) of the backrest (18), which point is assigned to the pivot point (L) of the drive lever (68) and the lengths of its lever arms so that the other end of the Connecting hinge (64-) remains practically stationary relative to the backrest (18). 2. Armchair according to claim 1, characterized in that the connecting joint (64 ·) and the drive lever (68) during said movement phase are arranged practically stationary relative to the backrest (18). 3. armchair according to claim 2, characterized in that the connecting joint (64) and between the drive pivot point (B) and the drive lever pivot point (L) lying lever arm of the drive lever (68) during said Movement phase lie on a line. 4. armchair according to one of the preceding claims, characterized in that a basic pivot point (P) of the chair 409818/0368 frame is arranged on a line (P-line) that bisects the angle (Θ) which is defined by a first line between the location (Am-y) of the operating pivot point (A) for the middle inclination position and the location (Bo) of the center of rotation (B) of the backrest (18) during said movement phase and is formed by a second line which runs between the location (Bp) of the center of rotation (B) of the backrest (18) during said movement phase and the location (A _R ) of the actuation pivot point (A) for the steep incline. 5. armchair according to claim M, characterized in that the drive lever pivot point (L) is arranged on a line (L-line) which is the median perpendicular of a line which runs between the location (A ₀ ) of the actuation pivot point (A) in the upright sitting position and the location (Α * φττ _s ) of a point on the backrest (18) for the upright sitting position 'which is close to the location (A _TV ) of the operating pivot point (A) when the armchair is in the middle inclined position. 6. armchair according to claim 4 or 5 »characterized in that that the location of the basic pivot point (P) is slightly offset from a theoretically precise geometric location, so that a relatively small movement of the headrest (22) relative to the backrest (18) takes place during the mentioned movement phase and a predetermined degree of inclination is maintained during this movement phase. 7. Armchair according to one of the preceding claims, characterized in that the drive lever (68) has two of the Drive lever pivot point (L) has lever arms extending perpendicular to each other and that the drive pivot point (D) in the 409818/0368 The seat position is below the actuation pivot point (A), both points behind the drive lever pivot point (L) lie. 409818/036