HK1168012B - Mechanism for a chair - Google Patents

Description

Mechanism for chair

Technical Field

The invention relates to a chair mechanism, in particular for a rotatable office chair with a pneumatic spring, which is arranged vertically in a base frame configuration for adjusting the seat height. When the backrest is tilted backwards (the user actuates this tilting by shifting his weight), the chair mechanism causes the seat to be lowered synchronously in the backward direction. In an advantageous variant, the chair mechanism enables the seat surface to be lowered forwards (so-called negative tilting) when the user moves his weight forwards, for example towards the table.

Background

A number of synchronization mechanisms for chairs are known, for example from patent documents EP0839478B1, EP1039816B1, EP1358821a1, WO2005/120291a1 and WO2007/124609a2, which are commercially available.

EP0592369B1 discloses a synchronizing mechanism for a work chair having a seat carrier and a backrest carrier which are arranged to be pivotable independently of each other in the same direction. The seat carrier is hingedly connected at the rear of the backrest carrier along the seat backrest carrier axis of rotation and at the front along the front seat axis of rotation. The front seat rotation axis is connected with the synchronous motion main rotation axis (which is provided by the longitudinal axis of the torsion spring) by a transfer plate which is fixedly attached to the front seat rotation axis and to the torsion spring. The conveying plate has a plate recess in which a stopper is provided for defining the pivoting area. The negative tilt region (when the chair mechanism is tilted forward) is connected about a negative tilt axis of rotation between the seat carrier and the back carrier upstream of the synchronously moving pivot region. Thus, the user may be provided with a pivoting area of the chair having a stepless transition from a forward tilted position to a backward tilted position, depending on his/her posture and weight distribution. The connecting operating elements of the synchronizing mechanism, the seat carrier, the conveyor plate, the torsion spring and the backrest carrier are arranged as a system on a negative tilting axis of rotation, arranged in the extension of the upright tube, and thus pivotable about said axis of rotation on the flexible seat support.

The object of WO2007/124609a2 is a mechanism with a base that is fixed to itself, through which a fixed first axis of rotation extends, and on which a tiltable seat carrier is mounted. A front connection device, which is connected in an articulated manner to the base in a fixed third axis of rotation and a movable fourth axis of rotation, is arranged between the base and the seat carrier. Furthermore, the mechanism has a rear connecting means which is connected in an articulated manner in a movable sixth axis of rotation at one end and in a further movable axis of rotation at the other end. At least one first spring element is provided in the mechanism, which acts between the base and the seat carrier and is connected in an articulated manner in a fourth rotational axis. At the other end, said first spring element is connected in an articulated manner in a movable eighth rotation axis, the position of which can be varied by means of a gear mechanism (which can be actuated by the user from the outside). Advantageously, the first spring element is a pneumatic spring which can be blocked by a brake element which can be actuated by a user, so that the seat and the backrest are locked in the rest position.

The present application is also based on WO2009/103389a1, which WO2009/103389a1 relates to a mechanism for an office chair. The mechanism has a movable drive element whose position changes during movement of the mechanism, and the movement characteristics of the mechanism change by the change in position of the movable drive element. In this case, the drive element is operatively connected to an operating element, the position of which changes during the movement of the mechanism upon a change in the position of the drive element, at least one characteristic of the change in the position of the drive element changing upon a change in the position of the operating element.

Disclosure of Invention

It is an object of the present invention, with respect to the known prior art, to provide a further improved synchronization mechanism which responds in a sensitive manner to movements of the weight. In particular, the object is to develop the ability to adjust the prestress of the machine in a more user-friendly manner for lighter or heavier people. Another object is to be able to vary the movement characteristics of the machine in a simple manner, for example for users having a height above average and/or a weight above average. It is also an object to develop a more versatile mechanism to enable different seating configurations to be used. Furthermore, the mechanism enables the chair to be provided with armrests and a backrest, which are attached in a flexible design. Finally, it can have a mechanism that is continuously produced at a cost-effective price.

The mechanism is designed for a chair, in particular for a rotatable office chair with a pneumatic spring which is arranged vertically in the chassis and has a telescopically extendable piston rod for adjusting the height of the seat. The adjustment of the inclination of the seat between the rest position and the rest position is synchronized with the adjustment of the backrest between the rest position and the inclined rearward rest position. The mechanism has a housing through which a fixed first axis of rotation extends and on which a tiltable seat carrier is mounted. A front connecting device is arranged between the seat carrier and the housing, which front connecting device is connected in an articulated manner to the housing in the second axis of rotation and to the seat carrier in an articulated manner in the third axis of rotation. A rear connection is provided, which is connected in an articulated manner in the first axis of rotation and in a fourth axis of rotation, which extends through the seat carrier. There is a spring system acting between the housing and the seat carrier. The mechanism has a force regulator which can be driven from the outside and which will serve to vary the prestress of the spring system by means of a gear configuration. The gear arrangement comprises a movable positionable means having an inclined surface thereon on which the rear bearing arrangement of the spring system is supported.

The following configurations are relevant to the particular design of the present invention: by combining the housing with the base arranged in said housing as a separate component, the seat can be adjusted between the rest position and the negative position when front loading by lowering the front edge of the seat.

The gear structure includes:

aa) a gear wheel rotatable by a rotational movement at the force adjuster;

ab) a longitudinally movable transmission member with teeth that engage the gear wheel.

ac) a first wedge member longitudinally movable by a transmission member; and

ad) an intermediate wedge attached to the first wedge, wherein the first wedge and the intermediate wedge are movable toward each other;

b) the spring system comprises two configurations parallel to each other, each configuration comprising an upper part telescopically connected to a lower part, wherein a helical spring is accommodated between the upper part and the lower part; and

c) the rear support construction of the spring system comprises two lower parts through which the shaft protrudes, a shaft and a central roller arranged on the shaft between the lower parts.

The transmission element is a rod part which has an external thread arranged thereon, on which a conveying device which strikes the first wedge is guided displaceably.

The intermediate wedge is arranged below the first wedge, is supported from below by a central roller, and rests at a front end against a column raised from the base. The upper component is associated with the front support configuration of the spring system.

A guide device is provided, which is connected to the seat carrier in an articulated manner on a fifth axis of rotation. A fifth axis of rotation on the guide extends through the transverse portion. Two arms parallel to each other project from the transverse portion. An outer roller arranged on the shaft is arranged in each lower part. In each case one of the outer rollers is guided on one of the arms of the guide device.

A roller supported on a control cam positioned on the base is arranged on the guide.

At a distance from one of the columns, a further column is raised from the base, the intermediate wedge rests against the one column, and the one column is adjacent to the conical opening for receiving the vertical pneumatic spring. The control cam is arranged to bridge the two posts.

The control cam is provided with a curved profile which has an effect on the movement characteristics of the mechanism. The curved profile of the control cam can be chosen according to whether the mechanism is provided for a user who is higher than the average height and/or heavier than the average weight or for a user who is lower than the average height and/or lighter than the average weight or according to the development of the backrest to which it is attached.

The front bearing configuration of the spring system is formed by its upper part and the bearing block in which the upper part is supported. The bearing block is mounted in the front region of the housing and has a housing in which the gear of the force regulator is mounted. A stop adjuster which can be driven from the outside and prevents the seat carrier from moving out of the rest position into a relaxed position, so that the backrest is also arranged below the bearing blocks.

The rear attachment means has a receiving member for attachment to the attachment member of the backrest. The receiving element surrounds the connecting device in a U-shaped manner, so that the connecting element with the projecting transverse strut and the two lateral struts can be pushed onto the receiving element from behind.

One connection with a guide piece extends from the seat carrier on each side to receive a complementary molded part of the armrest therein. The seat carrier is a separate component or is an integral part of the base plate of the seat.

A further spring system is provided which is supported from above by the lower part in the rear region of the housing and from below by the upper part in the rear region of the seat carrier.

Drawings

In the attached drawings

FIG. 1A shows a perspective view from above of a chair having the mechanism of the present invention, the chair in a resting position;

FIG. 1B illustrates a front view of the chair according to FIG. 1A;

FIG. 1C shows a perspective view of the chair according to FIG. 1A from below;

FIG. 1D illustrates a side view of the chair according to FIG. 1A, the chair in a resting position;

FIG. 1E shows a side view of the chair according to FIG. 1A, the chair being in a relaxed position;

FIG. 1F illustrates a side view of the chair according to FIG. 1A, the chair in a negative position;

FIG. 2A shows an exploded view of the mechanism assembly from above;

fig. 2B shows an exploded view of the component according to fig. 2 from below;

fig. 3A shows a perspective view of the housing according to fig. 2A from above;

fig. 3B shows a perspective view of the housing according to fig. 3A from below;

fig. 3C shows a different perspective view of the housing according to fig. 3A from above;

FIG. 4A shows a perspective view of the back carrier of FIG. 2A from above;

fig. 4B shows a perspective view of the backrest carrier according to fig. 4A from below;

fig. 4C shows a different perspective view of the backrest carrier according to fig. 4A from above;

FIG. 5A shows a perspective view of the base of FIG. 2A from above;

FIG. 5B shows a perspective view of the base according to FIG. 5A from below;

FIG. 5C shows a different perspective view of the base according to FIG. 5A from above;

FIG. 6A shows a perspective view of the guide of FIG. 2A from above;

fig. 6B shows a perspective view of the guide device according to fig. 6A from below;

FIG. 6C shows a different perspective view of the guide device according to FIG. 6A;

FIG. 7A shows a perspective view of the bearing block of FIG. 2A from above;

figure 7B shows a perspective view of the bearing block according to figure 7A from below;

figure 7C shows a different perspective view of the bearing block according to figure 7A from above;

FIG. 8A shows a perspective view of the seat carrier of FIG. 2A from above;

FIG. 8B shows a perspective view of the seat carrier according to FIG. 8A from below;

fig. 8C shows a different perspective view of the seat carrier according to fig. 8A from above;

FIG. 9A shows an exploded view of the base according to FIG. 5A from above with some of the components mounted;

FIG. 9B shows an exploded view of the combination of components according to FIG. 9A from below;

FIG. 9C shows a perspective view from above of the principle dispensing of the components according to FIG. 9A;

FIG. 9D shows a different perspective view of the assembly according to FIG. 9C;

fig. 9E shows a perspective view from above of the base according to fig. 5A with the trip device installed;

FIG. 9F shows the assembly according to FIG. 9E with a shield;

FIG. 9G shows the assembly according to FIG. 9F with the control cam therein;

FIG. 9H shows a different perspective view of the assembly according to FIG. 9G, with a first wedge and an intermediate wedge;

FIG. 9J illustrates a different perspective view of the assembly according to FIG. 9H, without the first wedge;

FIG. 9K shows a different perspective view of the assembly according to FIG. 9J with a first wedge and a first bumper;

FIG. 9L shows a different perspective view of the assembly according to FIG. 9K with bearing journals;

FIG. 9M shows an exploded view of the housing according to FIG. 9L from above with the height adjuster, stop adjuster and force adjuster and some other mounting components;

FIG. 10A shows an exploded view from above of the housing according to FIG. 3A with the height adjuster, stop adjuster and force adjuster and some other mounting components;

FIG. 10B shows a perspective view of the principle distribution of the components of the height adjuster, stop adjuster and force adjuster with the housing cover and the transmission component;

FIG. 10C shows a perspective side view of the assembly according to FIG. 10B;

FIG. 10D shows a different perspective view of the assembly according to FIG. 10C;

FIG. 10E shows a perspective view of the housing according to FIG. 3A from above with a stop adjuster installed;

figure 10F shows the assembly according to figure 10E with the bearing blocks;

FIG. 10G shows a different perspective view of the assembly according to FIG. 10F;

FIG. 10H shows the assembly according to FIG. 10G with the transmission member therein;

FIG. 10J shows a different perspective view of the assembly according to FIG. 10H, with a height adjuster and a force adjuster;

FIG. 10K shows a different perspective view of the assembly according to FIG. 10J;

FIG. 10L shows the assembly according to FIG. 10K, in a bottom view;

fig. 11A shows an exploded view of the backrest carrier according to fig. 4A from above;

FIG. 11B shows the assembly according to FIG. 11A after assembly;

FIG. 12 shows a perspective view of the pusher of FIG. 2A from above and below;

FIG. 13 shows a different perspective view of the retaining element of FIG. 2A;

FIG. 14A shows a perspective view of the second bumper of FIG. 2A from above and below;

FIG. 14B shows a different perspective view of the connector receptacle of FIG. 2A;

FIG. 14C shows a different perspective view of the second damper according to FIG. 14A with the connector receptacle according to FIG. 14B assembled;

fig. 15A shows a perspective view from below of the seat carrier according to fig. 8A, which is equipped with a pusher according to fig. 12, a holding element according to fig. 13, a second buffer according to fig. 14A and a connector socket according to fig. 14B;

FIG. 15B shows a perspective view of the assembly according to FIG. 15A from above;

fig. 16A shows an exploded view of the guiding device according to fig. 6A, with the bearing bush, the shaft, the roller and the insert;

FIG. 16B shows the assembly according to FIG. 16A after assembly;

FIG. 17A shows a perspective view of the housing with spring system and base with control cam of FIG. 2A from above after assembly;

FIG. 17B shows the assembly according to FIG. 17A and the assembly according to FIG. 11B after assembly;

figure 17C shows the assembly according to figure 17B, supplemented by the support block of figure 7A;

FIG. 17D shows the assembly according to FIG. 17C supplemented by the transfer member of FIG. 10B;

FIG. 17E shows the assembly according to FIG. 17D supplemented by the first wedge and intermediate wedge of FIG. 9A, without an axle pin;

FIG. 17F shows the assembly according to FIG. 17E supplemented by the force and height adjusters of FIG. 10B;

FIG. 17G shows the assembly according to FIG. 17F supplemented by the assembly according to FIG. 16B and the stop adjuster of FIG. 10B;

FIG. 18A shows a perspective view from below of the assembly according to FIG. 1SA, supplemented by the assembly of FIG. 16B, the plate and pin of FIG. 2A and the back carrier according to FIG. 4A;

FIG. 18B shows a different perspective view of the assembly according to FIG. 18A;

fig. 19A shows a perspective view from below of the assembly according to fig. 18A, supplemented by the pusher of fig. 2A, and the assembly according to fig. 17F below it, with the housing cover without the backrest carrier;

FIG. 19B shows a perspective view from above of the assembly according to FIG. 19A, with the blocking element of FIG. 10B inserted;

FIG. 19C shows a perspective view of the assembly according to FIG. 19A from below after assembly;

FIG. 20A shows a perspective view from below of a seat carrier contained in a seat;

fig. 20B shows a perspective view from below of the seat carrier according to fig. 20A, which is equipped with the plate according to fig. 2A, the assembly according to fig. 16B and the backrest carrier according to fig. 4A;

fig. 20C shows a perspective view from below of the assembly according to fig. 20B, which is equipped with the assembly according to fig. 19B and a bearing journal inserted on the first rotational shaft;

FIG. 21A shows a top view of the assembly according to FIG. 19C in a rest position;

FIG. 21B shows a vertical cross-sectional view taken along line A-A of FIG. 21A in a rest position with a higher force setting;

FIG. 21C shows a vertical cross-sectional view taken along line B-B of FIG. 21A in a rest position with a higher force setting;

FIG. 21D shows a vertical cross-sectional view taken along line C-C of FIG. 21A in a rest position with a lower force setting;

FIG. 21E shows a vertical cross-sectional view taken along line D-D of FIG. 21A in a rest position with a lower force setting;

FIG. 22A shows a top view of the assembly according to FIG. 19C in a relaxed position;

FIG. 22B shows a vertical cross-sectional view taken along line E-E of FIG. 22A in a relaxed position with a higher force setting;

FIG. 22C shows a vertical cross-sectional view taken along line F-F in FIG. 22A in a relaxed position with a higher force setting;

FIG. 22D shows a vertical cross-sectional view taken along line G-G of FIG. 22A in a relaxed position with a lower force setting;

FIG. 22E shows a vertical cross-sectional view taken along line H-H in FIG. 22A in a relaxed position with a lower force setting;

FIG. 23A shows a top view of the assembly according to FIG. 19C, in a negative position;

FIG. 23B shows a vertical cross-sectional view taken along line J-J of FIG. 23A in a negative position with a higher force setting;

FIG. 23C shows a vertical cross-sectional view taken along line K-K in FIG. 23A in a negative position with a higher force setting;

FIG. 23D shows a vertical cross-sectional view taken along line L-L of FIG. 23A in a negative position with a lower force setting;

FIG. 23E shows a vertical cross-sectional view taken along line M-M in FIG. 23A in a negative position with a lower force setting;

FIG. 24 shows a perspective view of the backrest of FIG. 1A without the cover; and

fig. 25 shows an armrest for mounting on the mechanism according to fig. 1C.

Detailed Description

Exemplary embodiments of the mechanism of the present invention and the sequence of movements will be described in detail hereinafter with reference to the accompanying drawings.

The following remarks apply to the remainder of the description. To avoid obscuring the drawings, reference will be made to the previous description of the drawings to which reference numerals are attached when they are included in the drawings but not explained in the directly relevant text of the specification. For purposes of clarity, when an element is clearly visible in the drawings where it is "re-exposed," it is not repeated in subsequent drawings in most cases.

FIGS. 1A to 1F

The mechanism 2 of the invention is arranged on a height-adjusting pneumatic spring 12, which height-adjusting pneumatic spring 12 is inserted by its upright tube 11 into a support 10, which support 10 is usually provided with floor-mobile elements 13 (in particular in the form of rollers). The support 10, which in this case is star-shaped, forms the base frame 1 together with the vertical tube 11, the height-adjusting pneumatic spring 12 and the floor-engaging element 13. The seat 9 is arranged on the mechanism 2, a link 97 is attached to the mechanism 2, the link 97 being incorporated into a backrest 96 which extends at a quasi-right angle (upwards) with respect to the seat 9. In the rest position according to fig. 1A to 1D, the seat 9 is arranged at a quasi-horizontal seat inclination S₀And the backrest 96 has an associated almost vertical backrest inclination R₀. In the relaxed position according to fig. 1E, the seat 9 is moved to a maximum seat inclination Smax and the backrest 96 assumes a maximum backrest inclination Rmax in a synchronized manner therewith. In the negative position according to fig. 1F, the seat 9 is moved to the forward facing seat inclination Smin and the backrest 96 is moved in a synchronized manner therewith to the minimum backrest inclination Rmin. Thus, the inclination of the seat 9 can be varied in the range of- α to + α by the seat angle α, while the inclination of the backrest 96 can be varied in the range of- β to + β by the backrest angle β. The rotation axis D0 is in the direction of extension of the vertical tube 11 and the pneumatic spring 12.

FIGS. 2A and 2B

The mechanism 2 is mainly composed of the following components:

a housing unit 3, the housing unit 3 having:

a housing 30, a pair of respective second support bushes 32, a plate 33, a support journal 35 and two pairs of first support bushes 34;

a base unit 4, the base unit 4 having:

a base 40, a trip device 41, a spring 42, a shield 43, a first bumper 44, a pair of bearing journals 45, a control cam 48, and a pair of stoppers 49;

a prestressing unit 5, the prestressing unit 5 having:

a support seat 50, a transmission member 51, a first wedge member 52, and a second wedge member 53;

a backrest carrier unit 6, the backrest carrier unit 6 having:

a back carrier 60 and a pair of respective first 68 and second 69 support bushings;

a guiding unit 7, the guiding unit 7 having:

a guide 70, a pair of rollers 71 and an insert 72, and a shaft 73;

a seat carrier unit 8, the seat carrier unit 8 having:

seat carrier 80, pusher 81, first shaft lever 84, one pair of each second buffer 85 and connector socket 86, and two pairs of each holding member 82, shaft pin 83 and one pair of slide rails 87;

a height adjuster 14, the height adjuster 14 having:

a lever 140, a multi-edge lever 141, and a handle;

housing cover 37

A stop adjuster 38, the stop adjuster 38 having:

an operating lever 380, a multi-limbal lever 381, a handle and a pair of respective blocking elements 383 and a conveyor 384;

a force regulator 39, the force regulator 39 having:

gear 390, multi-edged lever 391, guide tube 392, intermediate member 393, coil spring 394, spring guide 395, screw 396, sleeve 398, and handle 397; and

a spring system 46, the spring system 46 having:

a pair of respective coil springs 460, an upper member 461, a lower member 462 and an outer roller 463, and a center roller 464 and a shaft 465.

FIGS. 3A to 3C

The housing 30 has a lower portion 31 as a bottom surface, the lower portion 31 has a first recess 301 of a large area in front and rear regions, and a spring seat 307 is provided behind the first recess 301. The side walls, front wall and rear wall are raised from a bottom surface which is in principle rectangular. A wedge-shaped stop 314 is arranged at the transition between the first recess 301 and the spring seat 307. At the front end of the lower part 31, corner journals 313 are raised in the respective corner regions, the columns 310 being spaced from the corner journals. Behind each column 310 is a first support element 311, which first support element 311 is formed by two eye webs which are parallel to one another and through which a shaft bore arranged on the second axis of rotation D2 extends, which shaft bore emerges as a second shaft bore 305 in both side walls. The third shaft hole 303 opens out in the side wall near the front wall. The fourth shaft hole 304 opens outward at the same side wall between the third shaft hole 303 and the second shaft hole 305. Adjacent to the opposite side wall, the first support element 311 is followed by a second support element 312, which second support element 312 in turn comprises two eye-shaped webs which are parallel to each other, through which a fifth axle hole 316 extends, which fifth axle hole 316 is exposed at the relevant side wall. A first shaft bore 306 also opens out in each of the two side walls, through which bore a first axis of rotation D1 in the rear region of the housing 30 extends. The rotation axes D1, D2 are arranged parallel to each other. The housing 30 tapers in the region of the first shaft bore 306 to the rear end, so that an inclined ledge 308 is produced inside the side walls, on which inclined ledge 308 the raised portion 309 is arranged. Bed frame 315 is elevated from lower portion 31 with a shallow cavity 302 below lower portion 31. The outer bores of the first and second shaft bores 306, 305 are countersunk. There are two slots 317 in the lower portion 31 in the region of the cavity 302. The housing 30 is preferably constructed of aluminum and is manufactured as a cast component.

FIGS. 4A to 4C

The backrest carrier 60, which is U-shaped in principle, has two arms which are parallel to one another and through which, in each case near their free ends, a first shaft opening 61 extends, which opening lies on the first axis of rotation D1. The two arms are bridged by a transverse portion 65, a cheek portion 62 and a space 67, the cheek portion 62 carrying in each corner region and between the transverse portion 65 and the arms, the space 67 being centrally held between the two cheek portions 62. In each example, the second shaft hole 64 (through which the fourth rotational axis D4 extends) is disposed above the plane of the first shaft hole 61 and the first rotational axis D1, and near the transition from each arm to the transverse portion 65. The rotation axes D1, D4 are arranged parallel to each other. In each example, the notch 63 is disposed in the transverse portion 65 adjacent each cheek portion 62 and each second shaft aperture 64. A slot-shaped receiver 66 (in each case, this slot-shaped receiver 66 extends up to into the outer side of the two arms) is arranged on the outer surface of the transverse portion 65. A through hole 660 exists inside the receiving member 66.

FIGS. 5A to 5C

The lower portion 407 of the base 40 is approximately square with the side walls and members rising upwardly from the lower portion. A cone opening 400 (the cone opening 400 passing perpendicularly through the base 40 with the axis of rotation D0 extending through the cone opening 400) opens out on the lower portion 407 in the rear region of the base 40. One shaft bore 401 with an outwardly countersunk bore is exposed in each example in two opposing sidewalls. A first axis of rotation D1 extends through the shaft bore 401. A bed frame construction 402 (the bed frame construction 402 includes a plurality of vertical ribs spaced apart from one another with upwardly opening semi-circular grooves all of which are aligned with one another) is disposed between the tapered opening 400 and the rear end of the base 40. The aperture 408 is disposed adjacent to the bed frame structure 402. The molding slot 407 is disposed on the rear edge of the base 40. One post 403 is elevated near the tapered opening 400 and opposite the post, a further post 403 is elevated between the two cutouts 406. Two spherical cutouts 406 are present in the front wall. The base 40 is preferably constructed of aluminum and is fabricated as a cast component.

FIGS. 6A to 6C

In principle, the guide device 70 is U-shaped with a transverse portion 700 from which two arms 706 parallel to each other protrude, leaving an intermediate space 705. The rear end of the guide 70 is penetrated by a first shaft hole 704, and a fifth rotation axis D5 extends through the first shaft hole 704. In the vicinity of the transition from the arms 706 to the transverse part 700 (but already in the region of the intermediate space 705), the respective arm 706 is penetrated by a second axial bore 703, said axial bores 703 being aligned with one another. On the top surface, each arm 706 has a notch 707, which notch 707 is defined by a stop 708 near the transverse portion 700. The guide 70 is preferably constructed of a plastic material.

FIGS. 7A to 7C

In principle, the bearing block 50 is T-shaped with a transverse strut 500 from the middle of which the housing 505 protrudes. The outer ends of the transverse struts 500 each have a screw seat 501 and a cavity 502, the cavity 502 being open to the side of the housing 505. The receiving elements 504 exposed at the transverse strut 500 extend longitudinally through the housing 505. A semicircular cutout 506 extends transversely through the housing 505. Support 507 is attached to housing 505 and below the aperture of receiver 504. A frame construction 503 is arranged on the bottom surface of the bearing block 50, which frame construction 503 is formed by a plurality of mutually spaced vertical ribs with downwardly opening semi-circular grooves, all of which are mutually aligned. Further, a cam 509 is located on the bottom surface of the bearing block 50. The support 50 is preferably made of a plastic material.

FIGS. 8A to 8C

The seat carrier 80 comprises a plate 800, the plate 800 having an upper surface 801 and a bottom surface 802, on which bottom surface 802 the plate 800 is surrounded by edge-shaped walls. In each case, outwardly projecting connectors 803 project at the rear region of the plate 800, which connectors are aligned with one another, and in each case there is a guide 804. A second link 805 having a guide member 806 is connected to one link 803 and guided in parallel. A journal 8010 that rises toward the top surface 801 is disposed near a corner region of the plate 800. The top surface 801 has a plurality of exposed locking holes 8020, and the locking holes 8020 are distributed over the plate 800. Near the rear end and in the front region of the plate 800, two pairs of respective first support elements 807 project from its bottom surface 802, the first support elements 807 being in the form of vertically upstanding eyes having apertures extending transversely therethrough. The first support element 807 near the rear end defines a fourth axis of rotation D4, while the first support element 807 in the front region forms a third axis of rotation D3. Two second support elements 808, which are semi-hard shell shaped openings, are elevated from the bottom surface 802 approximately at the height of the protruding connection 803. Approximately centrally between the posterior first and second support elements 807 and 808 is a dome-shaped depression 809 in the bottom surface 802. The inner first support element 807, second support element 808 and recess 809 have locking holes 8020 associated therewith, the locking holes 8020 protruding through the plate 800. On the bottom surface 802, between each pair of first support elements 807 in the front region of the plate 800 and its front edge, there is a blind hole 8021. A rectangular through-section 8024 surrounded by a recess 8023 on the bottom surface 802 is exposed in the middle of the top surface 801 of the board and between the two connectors 803.

FIGS. 9A and 9B

The trip device 41 is composed of a shaft pin 410 and an arm beam 411 fixedly attached to one end thereof, and an operating rod-shaped pressure member 412 fixedly attached near the other end of the shaft pin 410. The pressure member 412 has a hook 413 protruding outward. The shield 43 has a cover portion 430, the cover portion 430 having a fixing portion 431 at each end. Each fixing portion 431 has a hole 432 for passing a screw 439 therethrough. In cross section, the first bumper 44 has a double T shape. The bearing journal 45 has a head 450 with a shaft portion 451 extending from the head 450, the shaft portion 451 terminating freely in a threaded portion 452. The center cam 48 is formed as a plate having a rectangular bottom surface, and the top surface is formed as a cam plate. Stops 49 can be arranged on each side of the base 40, said stops being used for damping in the event of a sudden movement of the mechanism 2 from the negative position to the rest position. The first wedge-shaped member 52 has a coupling member 520 at one end, the coupling member 520 including an inclined portion 522. The other end of the first wedge 52 has two fork prongs 521, which prongs 521 enclose a space 523. At the front end, the intermediate wedge 53 has a raised inclined surface 530, and in each case on both sides a groove 532, which groove 532 is parallel to the inclined surface 530, and also an inclined rear surface 531.

FIGS. 9C to 9M

This series of drawings illustrates the principle distribution of components that are substantially connected to the base 40 in a serial assembly, without regard to the actual assembly sequence.

FIGS. 9C and 9D

The shaft pin 410 of the trip device 41 is covered by the shield 43, and the pressure member 412 protrudes from the middle of the shaft pin 410. The beam 411 protrudes from one end of the shield 43. One end of the spring 42 disposed on the shaft pin 410 is held under the hook 413. In principle, the parts 411, 412 project in the same direction. The claws (not shown) projecting from the inclined portions 522 are inserted into the two grooves 532 of the intermediate wedge 53 with its rear surface 531 facing the shield 43. The control cam 48 is disposed above the first wedge 52.

FIGS. 9E to 9G

The pin 410 of the trip unit 41 rests on the bed frame structure 402 of the base 40 and the pressure member 412 projects into the tapered opening 400. The second end of the spring 42 is supported on the rear end of the base 40, so that the trip device 41 must be driven against the action of the spring 42. The shield 43 is fitted into the pin 410 and the spring 42 is placed thereon. The control cam 48 is arranged on both posts 403 so as to bridge them.

FIGS. 9H to 9L

The rear surface 531 of the intermediate wedge 53, arranged below the control cam 48, faces the internal post 403, while the groove 532, close to the inclined surface 530, is in sliding engagement with the first wedge-shaped element 52. The fork prongs 521 terminate in the area of the two cut-outs 406 of the base 40. The bumper 44 is inserted into the molded channel 4070. The upper region of outer post 403 is disposed in space 523 of first wedge 52. The bearing journal 45 is used for subsequent connection between the backrest carrier 60, the housing 30 and the base 40 along a first rotation axis D1.

FIG. 9M

The spring system 46 is suspended on a shaft 465, which shaft 465 is arranged in the middle of a central roller 464 (not shown here). On both sides of the central roller 464, a rotatable outer roller 463 is arranged on each shaft 465, which shaft 465 projects with its ends through the lower part 462 in each case. Each lower part 462 is engaged in a telescopic manner in the relative upper part 461, the helical spring 460 being axially housed between said upper and lower parts 462, 461. Thus, the spring system 46 has two springs 460, the two springs 460 acting in parallel with each other. The bottom surface of the intermediate member 53 is supported on the center roller 464. The support of the outer roller 463 can be described later. The spring system 46 projects into the base 40 through the lower part 462 and the adjacent regions of the helical spring 460. The other part of the spring system 46 projects out of the base 40 through two cut-outs 406 in said base.

FIGS. 10A to 10L

This series of figures illustrates the principle assignment of components that are substantially connected to the housing 30 in a serial assembly without regard to the actual assembly sequence.

FIGS. 10A to 10D

Just like the bearing journal 45, the bearing journal 35 also has a head 350 with a shaft portion 351 extending from the head 350, the shaft portion 351 terminating freely in a threaded portion. In each example, the ovoid plate 33 has a through hole 330 near each of its two outer ends.

The height adjuster 14 for driving the trip device 41 includes: a handle 142; a multi-edge rod 141 into which the multi-edge rod 141 is firmly inserted; and a lever 140, the lever 140 being fixedly mounted on the multi-edged lever. In the mounted state, the detent adjuster 38 rests on the upper face of the front edge of the housing cover 37, the detent adjuster 38 comprising: a handle 382; a multi-edged rod 381, the multi-edged rod 381 being securely inserted therein; and an operating lever 380, the operating lever 380 being fixedly arranged on the multi-edged lever. The lever 380 has a locking profile 385, which locking profile 385 consists of two adjoining grooves. The transport device 384 is in each case connected to the multi-limbed rod 381 near the handle 382 and behind the outside of the operating rod 380. Each conveyor 384 extends to a plate-shaped blocking element 383 so that, when the stop adjuster 38 is rotated, the blocking element 383 is raised. The detent adjuster 38 is movable to two self-locking positions. The cam of the bearing block 50 is placed in one of the two recesses of the locking profile 385, and the polygonal rod 381 is fixed at the free end with a nut 389 for retaining the operating rod 380. A force adjuster 39, which terminates on the outside at a handle 397, is positioned on the housing cover 37 and in front of the blocking element 383. Inside the connecting member 393 is a tubular spring guide 395 which is adapted to receive a coil spring 394. Spring guide 395 is secured by axial lead-in screws 396. A guide tube 392 (from which a multi-edge rod 391 emerges from the guide tube 392) projects to the outside of the connecting member 393, and a gear 390 is fixed to the free end of the guide tube 392. The teeth 511 on the front end of the lever portion 510 of the transmission member 51 engage with the gear 390. The other end of the stem portion 510 is provided with an external thread on which a delivery device 513 runs so as to be longitudinally adjustable along the external thread as the force adjuster 39 is rotated and rotational motion is imparted to the stem portion 510. The conveyor 513 has two wing-shaped attachments projecting outwards.

FIGS. 10E to 10H

The entire stop adjuster 38 is inserted laterally into the front region of the housing 30, the blocking element 383 rests against the post 310, and the knob 382 projects from the third shaft aperture 303 and is thus accessible to the user. The bearing block 50 is inserted into the front region of the housing 30 onto the stop adjuster 38 and screwed with the corner journal 313 by means of a threaded socket 501. The bed base 315 is raised from the lower part 31, which bed base 315 in principle comprises two vertical webs that are parallel to each other and recesses that are present therein. The housing of the bearing 50 rests against the bed frame 315. The cutout 506 in the housing 505, together with a complementary cutout in the bed frame 315, forms a circular opening for receiving the gear 390, which gear 390 rests on the polygon bar 391. The teeth 511 are inside the bedframe 315, the housing 505 is screwed thereto, and the rest of the transfer member 51 is arranged between the wheels of the bedframe 315 and the supports 507 continuing from the housing 505. The blocking element 383 is therefore surrounded by the cavity 502 in the bearing block 50.

FIGS. 10J to 10L

The entire force regulator 39 is inserted, and the gear 390 is inserted into the expansion slit 506 and internally engaged with the teeth 511 of the transmission member 51. The free pin end of gear 390 is disposed in the exposed expansion slot 506. The multi-edged rod 391 penetrates the adjacent column 310 and is exposed outside the fourth shaft hole 304 together with the guide tube 392 to enable a user to grasp the handle 397. The entire height adjuster 14 is also inserted, the operating lever 140 non-rotatably arranged on the polygon bar 141 is interposed between the two second support members 312, and the free pin end of the polygon bar 141 is rotatably inserted into the inner support member 312. The transition from the multi-edged lever 141 to the handle 142 protrudes to the outside through the fifth shaft hole 316 to enable the handle 141 to be reached by the user. The free end of the lever 140 faces the rear region of the housing 30. For the subsequent fixing of the plate 33, bearing journals 35 are used, which bearing journals 35 are placed by their head 350 in shaft bores 305, which shaft bores 305 are exposed on both sides of the housing 30 and have countersunk holes. The shaft portions 351 extend in each example along a second axis of rotation D2 between the associated pair of first support elements 311, with the respective threaded portions 352 engaging in the associated inner first support elements 311. The cavity 302 below the lower portion 31 of the housing 30 can be closed by the housing cover 37. This cavity 302 can be used, for example, for inserting operation and maintenance instructions.

FIGS. 11A and 11B

The first support bushing 68 through which the first rotational axis D1 is aligned is used to mount the back carrier 60 and is to be inserted into the two first shaft holes 61 in the carrier. The second bearing bush 69 is to be inserted into the second shaft hole 64, and the fourth rotation axis D4 extends through the second shaft hole 64 to receive the shaft pin 83 therein.

FIGS. 12 to 14C

The pusher 81, which is in principle cuboid in shape, has a longitudinal part 810, which longitudinal part 810 merges at one end into the raised head 811. A locking profile 812 facing the longitudinal part 810 is located on the head 811. The spring 814 is inserted into the pusher 81.

The holding element 82 has a plate 820 which is rectangular in principle and from which plate an attachment 821 formed by the plate (which attachment 821 is approximately of equal size) projects at right angles. Outwardly facing arm locking members 822 project from the two narrow sides of the plate 820.

The second bumper 85 is substantially formed with a U-shaped portion 850. The front ends 851 are mounted on respective free ends of the sides of the U-shaped portion 850, the two front ends 851 being aligned with each other.

The connector receptacle 86 is an irregularly formed body having an axially disposed blind bore 860 and a hook 862 extending axially relative to the blind bore 860. The connector receptacle 86 has outwardly directed arm lock members 861 on each of the outer side surfaces. When connector receptacle 86 is locked with second bumper 85, U-shaped portion 850 encompasses hook 862 and leading end 851 engages behind hook 862.

FIGS. 15A and 15B

This pair of figures shows the principle allocation of the components 81, 82, 85, 86, 87 connected to the seat carrier 80, irrespective of the actual assembly sequence. The pusher 81 is inserted through its bottom surface and its head 811 is first inserted into the second connector 805. The pusher 81 can be arranged opposite to the spring 814 in the longitudinal extension of the second connector 805. In each example, retaining element 82 is positioned on an inner side of each inner first support element 807. In each example, the plate 820 is disposed on the bottom surface 802 of the seat carrier 80, the attachment 821 abuts against the first support element 807, and the locking member 822 is engaged through the locking hole 8020 in the plate 800. The attachment 821 projects partially to the front of the shaft hole in the first support element 807. In each case, the connection socket 86 (with the second damper 85 locked thereon) is arranged on the second support element 808. In this example, the second bumper 85 is disposed adjacent a side wall of the seat carrier 80 and the locking member 861 is engaged through a locking aperture 8020 associated with the second support element 808. The assembly of blind holes 860 of the connection socket 86 is arranged along the fifth rotation axis D5 and facing each other. In order to be arranged on both outer sides of the top surface 801 of the seat carrier 80, in each case a slide rail 87 is provided, which slide rail 87 is suspended on a journal 810 projecting through the slide rail 87, which journal 810 is elevated from the top surface 801.

FIGS. 16A and 16B

For mounting the guide device 70, the first shaft 84, which in the inserted state projects outwards from the side of the guide device 70, is arranged to be inserted into a first shaft hole 704 of said guide device, through which first shaft hole 704 the fifth rotation axis D5 is aligned. The two rollers 71 will be arranged on the second shaft 24 and the second shaft 24 will be inserted into the second shaft hole 703. In this example, the roller 71 is placed in the space 705. In each case, a plate-shaped insert 72 is inserted into the recesses 707 of the two arms 706 of the guide device 70, the position of this insert 72 being fixed by a stop 708. The guide 70 is preferably constructed of a plastic material, while the insert 72 has greater wear resistance, for example being made of sheet metal.

FIGS. 17A to 17G

This series of figures shows the principle distribution of the components connected to the housing 30 and the base 40 inserted therein in successive assembly, without taking into account the actual assembly sequence.

FIGS. 17A to 17C

The lower part 462, the outer roller 463, the central roller 464 and the shaft 465 of the spring system 46 are arranged in the region of the two posts 403. A coil spring 460 (having an upper member 461 disposed thereon) projects to a front region of the housing 30. The back carrier 60 (with the first support bushing 68 inserted into the first shaft hole 61) surrounding the rear component of the housing 30 is positioned along the first rotational axis D1. The first axle holes 306, 61 of the shell 30 and the back carrier 60 are aligned with each other. The second bearing bush 69 is inserted into the second axle hole 64 of the backrest carrier 60, which second bearing bush 69 receives the axle pin 83 and forms a fourth axis of rotation D4. When the bearing block 50 is inserted into the front region of the housing 30, the upper part 461 of the spring system 46 bears against the transverse strut 500. The housing 505 with the support 507 is placed between the two upper members 461. Until now, the cavity 502 between the post 310 of the housing 30 and the bearing block 50 is unoccupied.

FIGS. 17D and 17E

The lever portion 510 of the transfer member 51 is inserted into the receiving member 504 of the housing 505. The conveyor 513 of the transfer element 51 strikes against the first wedge 52, which first wedge 52 rests on the intermediate wedge 53. An intermediate wedge 53 carried by a central roller 464 is arranged below the first wedge-shaped element 52.

FIG. 17F

The entire height adjuster 14 is plugged in with the associated trip device 41. In this case, the operating lever 140 of the height adjuster 14 (which operating lever 140 can be driven at the outer handle 142) is arranged on a beam 411 of the tripping device 41. When the height adjuster 14 is actuated, the pressure member 412 can be depressed against the action of the spring 42 to release the height adjustment pneumatic spring 12 for adjustment.

FIG. 17G

The entire stop adjuster 38 is installed. Blocking element 383 is now inserted into cavity 502 (cavity 502 is unoccupied until now). Indicating the positioning of the guide device 70, which in the mounted state is fixed on the seat carrier 80 along the fifth axis of rotation D5. Two rollers 71 of the guide 70 are arranged on the control cam 48. The two outer rollers 463 of the spring system 46 are arranged on an insert 72, which insert 72 serves for the guide device 70.

FIGS. 18A and 18B

In each example, the plate 33 is mounted in two front first support elements 807 on the seat carrier 80. The first support bush 34 is inserted into the two through holes 330 of the plate 33. The axle pin 83 protrudes through the axle holes of the two first support elements 807 and the plate 33, and the first support bushing 34 is arranged in the associated through hole 330. The axle pin 83 is held in an axial position at one end by a side wall of the seat carrier 80 and at the other end by the lock retaining element 82. Thus, the plate 33 is hingedly connected at one end in the third rotation axis D3. The second axis of rotation D2 extends through a further through hole 330 of the plate 33, which through hole 330 up to now has only been provided with the first bearing bush 34.

The backrest carrier 60 is hingedly connected to the seat carrier 80 along a fourth axis of rotation D4 in the same manner. In this example, the second bearing bush 69 is arranged in the second shaft bore 64, and the shaft pin 83 is inserted into the bearing bush 69. The pivot pins 83 again project through shaft holes in the first bearing element 807, which shaft holes receive between them the respective surrounding areas of the second shaft hole 64 of the backrest carrier 60. The side walls of the seat carrier 80 and the retaining elements 82 locked thereon again bring about an axial positioning.

The guide arrangement 70 is arranged on the seat carrier 80 along a fifth axis of rotation D5. In this example, one connector receptacle 86 is disposed on each end of the first shaft 84 that projects outside of the first shaft aperture 704 and receives the associated shaft end in a blind bore 860. The connector receptacle 86 is locked to the second support element 808. A second buffer 85 connected with the associated connector receptacle 86 is provided between the side wall of the seat carrier 80 and each adjacent connector receptacle 86. The through portion 8024 and the recess 8023 on the bottom surface 802 of the seat carrier 80 provide space for the pivoting guide 70.

FIGS. 19A to 19C

When the mechanism 2 is in the fully mounted condition, the end of the plate 33 (which end is up to now free) is suspended between the pairs of first supporting elements 311 so that the relative shaft holes are all aligned with one another, and the bearing journal 35 is inserted, the head 350 of said bearing journal 35 being placed in the second shaft hole 305, the shaft portion 351 projecting through the first supporting bush 34 which has not been occupied up to now, and the threaded portion 352 being inserted in the inner first supporting element 311. A connection on the second axis of rotation D2 is thus produced. In the remaining bearing journal 45, the head 450 is arranged externally on the first shaft opening 61 of the backrest carrier 60, the shaft portion 451 projects through a first bearing bush 68 and a second bearing bush 32, the first bearing bush 68 being arranged in the first shaft opening 61 of the backrest carrier 60, the second bearing bush 32 being arranged in the first shaft opening 306 of the housing 30. Finally, the threaded portion 452 of the bearing journal 45 is inserted into the shaft hole 401 of the base 40, which is provided with an internal thread. Thus, the connection between the back carrier 60, the shell 30 and the base 40 is made along the first rotation axis D1. Two rollers 71 of the guide 70 are arranged on the control cam 48, the outer roller 463 of the spring system 46 being supported on an insert 72 inserted in the guide 70.

The depth of the seat 9 arranged on the mechanism 2 can be adjusted using a pusher 81, which pusher 81 is inserted into the second connection 805 of the seat carrier 80. In this example, when the pusher 81 is pushed forward, its locking profile 812 disengages from the complementary profile on the seat 9.

When the relaxed position is reached, the position of the seat 9 is Smax and the position of the backrest 96 is Rmax, the second bumper 85 in the seat carrier 80 is in contact with the plateau 309 in the housing 30. When the negative position is reached, the position of the seat 9 is Smin, the position of the backrest 96 is Rmin, and the top surface of the stopper 314 in the housing 30 hits down the first bumper 44 provided in the molded groove 4070 of the base 40.

FIGS. 20A to 20C

In this example of a simplified seat carrier 80, the device for adjusting the depth of the seat 9 is omitted, and therefore the second connection 805 is omitted. The seat carrier 80 is an integral part of the seat 9 and is preferably formed as the bottom surface of a pad. Instead of the first support elements 807 being arranged in pairs, in each case only one such element is provided here. The locking hole 9020 is omitted. The first bearing element 807 is arranged along the fifth rotation axis D5 instead of the second bearing element 808. The side wall of the seat carrier 80 has an opening 8022 along the third rotation axis D3 and the third rotation axis D4 for receiving the end of the associated shaft therein. Also in this seat carrier 80, the two plates 33 are arranged along a third axis of rotation D3, the backrest carrier 60 is arranged along a fourth axis of rotation D4, and the guide arrangement 70 is arranged along a fifth axis of rotation D5. Furthermore, the plate 33 along the second rotation axis D2 is permanently connected with the first support element 311 in the housing 30. Finally, the backrest carrier 60, the housing 30 and the base 40 arranged therein are connected together along a first axis of rotation D1 by means of a bearing journal 45, thus forming the variant mechanism 2.

FIGS. 21A to 23E

The series of figures shows the sequence of movement of the mechanism 2, mainly from the rest position S0/R0 towards the relaxed position Smax/Rmax and towards the negative position Smin/Rmin, with higher and lower force settings in each instance. In each case, a top view of the mechanism 2 used has a central and eccentric vertical section.

FIGS. 21A to 21C

The mechanism 2 is arranged in a rest position, i.e. the seat 9 is in position S0 and the backrest 96 is in position R0. The force adjuster 39 is set in a higher force setting position so that the mechanism 2 is adjusted for heavier persons who have their heavier weight against the backrest 96, thus requiring higher resistance to deflection.

The conveyor 513, which extends in the direction of the column 403 in the largest manner on the lever portion 510 of the transmission element 51, causes the first wedge-shaped element 52 to move in the same direction while the intermediate wedge-shaped element 53 is depressed. The deeper position of the intermediate wedge 53 provided on the central roller 464, which central roller 464 is arranged on the shaft 465, which shaft 465 extends through the prestressed spring system 46, lowers the spring system 46 more deeply, which is suspended on the shaft 465. The two outer rollers 463 of the spring system 46 are supported on respective tilting inserts 72 on the guide arrangement 70. A roller 71 on the guide 70 is provided on the control cam 48. Due to the longer lever arm formed between the fifth rotation axis D5 and the shaft 465, an increased force is required (by the user bearing against the backrest 96) to move the mechanism 2 to the relaxed position. The lower part 462 is moved closer to the upper part 461 and the helical spring 460 is therefore more highly prestressed. Therefore, the user must exert a greater force to move the backrest 96 in the direction of the rest position Rmax, i.e., on the other hand, a heavier person is more firmly supported by the backrest 96. The seat carrier 80 and the back carrier 60 are disposed in an undeflected position.

FIGS. 21A, 21D and 21E

The mechanism 2 continues to be in the rest position, i.e. the seat 9 position is S0 and the backrest 96 position is R0. The force adjuster 39 is located in a lower force setting position so that the mechanism 2 adjusts to the fact that lighter persons, who have their smaller weight against the backrest 96, require less resistance to deflection.

The transport device 513, which extends in a minimal manner in the direction of the column 403 on the lever portion 510 of the transmission element 51, enables the first wedge-shaped element 52 to advance in the direction of the transverse strut 500, while the intermediate wedge-shaped element 53 is raised. The higher position of the intermediate wedge 53 means that the spring system 46 suspended on the shaft 465 is lowered less. In principle, the roller 71 on the guide 70 is arranged on the control cam 48 unchanged. Due to the shorter lever arm formed between the fifth rotation axis D5 and the shaft 465, a reduced force (by the user bearing against the backrest 96) is required to move the mechanism 2 to the relaxed position. The lower part 462 is further away from the upper part 461 and the helical spring 460 is thus less prestressed. Therefore, the user needs to use less force to move the backrest 96 in the direction of the relaxed position Rmax, i.e., a lighter person is less firmly supported by the backrest 96. The seat carrier 80 and back carrier 60 remain disposed in the undeflected position.

FIGS. 22A to 22C

The mechanism 2 is in a relaxed position, i.e. the seat 9 is in a position Smax and the backrest 96 is in a position Rmax. The force adjuster 39 is located in a higher force setting. When the backrest 96 is tilted, the seat carrier 80 is moved synchronously to a maximum seat inclination Smax due to the articulated connection in the fourth axis of rotation D4 between the seat carrier 80 and the backrest carrier 60 (which is pivotable about the first axis of rotation D1). At the same time, the plate 33 suspended along the rotation axes D2, D3 moves, the guide means 70 held in the fifth rotation axis D5 pivoting in the direction of the spring system 46, so that the helical spring 460 is under greater stress. This is achieved by the outer rollers 463 pressing against the guide 70 and the central roller 464 pressing against the intermediate wedge 53, and now standing towards the transverse strut 500 substantially at the tip of the intermediate wedge 53. Furthermore, the roller 71 of the guide device 70 moves on the control cam 48 towards its edge. The guide 70 pressing against the outer roller 463 is not able to release the spring system 46. The user is most supported by the backrest 96 before reaching the fully relaxed position and is most concentrated when it is in the upright position.

FIGS. 22A, 22D and 22E

The mechanism 2 is again in the relaxed position. The force adjuster 39 is now at the lower force setting. The first wedge-shaped element 52 is moved back in the direction of the transverse strut 500, the intermediate wedge-shaped element 53 thus being able to move upwards towards the control cam 48. Synchronous motion is generated between the backrest 96 and the seat carrier 80 as shown in fig. 22B and 22C. Thus, the guide means 70 held in the fifth axis of rotation D5 is pivoted again in the direction of the spring system 46 in order to compress the helical spring 460. This is again done by means of an outer roller 463, which presses on the guide 70, and a central roller 464, which presses against the intermediate wedge 53 and is now close to the tip of the intermediate wedge 53 towards the transverse strut 500. Furthermore, the roller 71 of the guide device 70 is again moved on the control cam 48 towards its edge.

FIGS. 23A to 23C

The mechanism 2 is in the negative position, i.e. the position of the seat 9 is Smin and the position of the backrest 96 is Rmin. The connection between the housing 30 and the seat carrier 80 is lowered at the front edge of the seat about the first rotation axis D1, while the base 40 remains stationary. The force adjuster 39 is set at a higher force setting as shown in fig. 21B and 21C. The roller 71 of the guide 70 is arranged substantially centrally on the control cam 48. The first wedge-shaped member 52 moves in the direction of the column 403 in the vicinity of the tapered opening 400 in the largest manner, and the intermediate wedge-shaped member 53 supported thereon moves downward. The center rollers 464 are provided on the facing sliding surfaces of the intermediate wedge members 53 in a slightly eccentric manner, similarly to fig. 21B.

FIGS. 23A, 23D and 23E

The mechanism 2 continues to be in the negative position, that is to say the connection between the housing 30 and the seat carrier 80 is lowered around the first axis of rotation D1 at the front edge of the seat. The force adjuster 39 is now set at the lower force setting. The roller 71 of the guide 70 is placed on the control cam 48 as shown in fig. 23B and 23C. The positions of the first wedge-shaped pieces 52 and the intermediate wedge-shaped pieces 53 correspond to fig. 21D and 21E. The control rollers 464 are arranged in an almost central manner on the facing sliding surfaces of the intermediate wedge 53.

FIGS. 24 and 25

The backrest 96 has a frame 973, which frame 973 merges at the lower part into a transverse strut 971. Holes for connection, preferably screw connection, with holes 660 present in the backrest carrier 60 are present in the transverse struts 971. Two side struts 972 project from the transverse strut 971, the two side struts 972 being positioned opposite each other in a U-shaped manner and each having a mounting seat 976. The mounting seat 976 is complementarily formed for attachment to the receiver 66 of the back carrier 60.

The uppermost armrest 98 has a pad member 981 from which a support 980 extends downwardly, the support being incorporated into a curved middle member 983. The molded part 984 is connected to the intermediate part 983. The molded part 984 is formed in a complementary manner for insertion into the guide 804 of the support 803 of the seat carrier 80.

In the following it is also possible to propose in particular a replacement for the base 40 (which base 40 was inserted as a separate component up to now into the housing 30), so that the mechanism 2 can be moved to a negative inclination. When a negative inclination is not required, the housing 30 and the base 40 are realized as a single piece, i.e. the functional configuration on the base 40 for the synchronous movement between the backrest 96 and the seat carrier 80 is completely contained in the housing 30.

Claims (12)

1. A mechanism (2) for a chair having a pneumatic spring (12) arranged vertically in a chassis (1) and having a telescopically extendable piston rod for adjusting the height of a seat (9), wherein:

a) the seat (9) is in a rest position (S)₀) And a relaxed position (Smax) with the backrest (96) in a rest position (R)₀) And a backward tilt release position (Rmax);

b) the mechanism (2) has a housing (30) through which a fixed first axis of rotation (D1) extends and on which housing (30) a tiltable seat carrier (80) is mounted;

c) a front connecting means (33) is arranged between the seat carrier (80) and the housing (30), said front connecting means being hingedly connected to the housing (30) along a second axis of rotation (D2) and to the seat carrier (80) along a third axis of rotation (D3);

d) providing a rear connecting means (60) connected in an articulated manner along a first axis of rotation (D1) and along a fourth axis of rotation (D4) extending through the seat carrier (80);

e) a spring system (46) acting between the housing (30) and the seat carrier (80);

f) the mechanism (2) has a force regulator (39) which can be driven from the outside and which serves to vary the prestress of the spring system (46) by means of a gear arrangement (390, 51, 52, 53), characterized in that:

g) the gear arrangement (390, 51, 52, 53) comprising a movable positionable device (52, 53) having an inclined surface thereon on which a rear bearing arrangement (462, 464, 465) of the spring system (46) is supported;

by combining this housing (30) with a base (40) arranged in said housing and as a separate component, the seat (9) can be brought into a rest position (S) by lowering the front edge of the seat (9) when loaded in front₀) And a negative position (Smin).

2. Mechanism (2) according to claim 1, characterized in that:

a) the gear structure (390, 51, 52, 53) includes:

aa) a gear (390) which is rotatable by a rotational movement at the force adjuster (39);

ab) a longitudinally movable transmission member (51) having teeth (511) which engage with the gear wheel (390);

ac) a first wedge-shaped element (52) which can be moved longitudinally by means of the transmission element (51); and

ad) an intermediate wedge (53) attached to the first wedge (52), wherein the first wedge (52) and the intermediate wedge (53) are movable towards each other;

b) the spring system (46) comprises two configurations parallel to each other, each configuration comprising an upper part (461) telescopically connected to a lower part (462), wherein a helical spring (460) is accommodated between the upper part (461) and the lower part (462); and

c) the rear bearing construction (462, 464, 465) of the spring system (46) comprises two lower parts (462), a shaft (465) projecting through the two lower parts (462), and a central roller (464) arranged on the shaft (465) and between the two lower parts (462).

3. Mechanism (2) according to claim 2, characterized in that: the transmission element (51) has a rod part (510) with an external thread arranged thereon, on which a conveying device (513) striking against the first wedge (52) is guided movably.

4. Mechanism (2) according to claim 2 or 3, characterized in that:

a) the intermediate wedge (53) is arranged below the first wedge (52), is supported from below by the central roller (464), and rests at the front end against a column (403) raised from the base (40); and

b) the upper part (461) is associated with a front support formation (461, 50) of the spring system (46).

5. Mechanism (2) according to claim 4, characterized in that:

a) -providing a guide means (70) hingedly connected to the seat carrier (80) along a fifth axis of rotation (D5);

b) the fifth axis of rotation (D5) on the guide means (70) extends through the transverse portion (700);

c) two arms (706) parallel to each other extend from the transverse portion (700);

d) outer rollers (463) arranged on the shaft (465) are arranged in each of the lower parts (462); and

e) one of said outer rollers (463) is guided on one of said arms (706) of the guide arrangement (70).

6. Mechanism (2) according to claim 5, characterized in that: a roller (71) supported on a control cam (48) which is positioned on the base (40) is arranged on the guide (70).

7. Mechanism (2) according to claim 6, characterized in that:

a) at a distance from the one column (403), a further column (403) is raised from the base (40), the intermediate wedge (53) resting against the one column, and the one column being adjacent to a conical opening (400) for receiving a height-adjusting pneumatic spring (12); and

b) the control cam (48) is arranged to bridge two posts (403).

8. Mechanism (2) according to claim 6, characterized in that:

a) the control cam (48) is provided with a curved profile which has an effect on the movement characteristics of the mechanism (2); and

b) the curved profile of the control cam (48) can be chosen according to whether the mechanism (2) provides a chair for users higher or heavier than average height or lower or lighter than average weight, or according to the development of the backrest (96) to which it is attached.

9. Mechanism (2) according to claim 4, characterized in that:

a) the front bearing (461, 50) of the spring system (46) is formed by its upper part (461) and a bearing block (50) in which the upper part (461) is supported;

b) a bearing block (50) is mounted in a front region of the housing (30) and has a housing (505) in which the gear (390) of the force regulator (39) is mounted; and

c) a stop adjuster (38) is arranged below the bearing block (50), which can be driven from the outside and prevents the seat carrier (80) from leaving the rest position (S)₀) Moves to a relaxed position (Rmax) and thus also prevents the backrest (96) from leaving the rest position (S)₀) Move to the relaxed position (Rmax).

10. Mechanism (2) according to any one of claims 1 to 3, characterized in that:

a) the rear attachment device (60) having a receiver (66) for interfacing with an attachment member (97) of the backrest (96); and

b) the receiving element (66) surrounds the rear connecting device (60) in a U-shaped manner, so that the connecting element (97) can be pushed onto the receiving element (66) from behind, the connecting element having its transverse strut (971) and two lateral struts (972) projecting from it.

11. Mechanism (2) according to any one of claims 1 to 3, characterized in that:

a) a connecting part (803) with a guide (804) projects from the seat carrier (80) on each of two sides, in order to accommodate a complementary moulded part (984) of an armrest (98) therein; and

b) the seat carrier (80) is a separate part or an integral part of the base plate of the seat (9).

12. Mechanism (2) according to any one of claims 1 to 3, characterized in that: an additional spring system is provided, which is supported from above by a lower part in the rear region of the housing (30) and from below by an upper part in the rear region of the seat carrier (80).