EP2010027A2

EP2010027A2 - Mechanism for a chair

Info

Publication number: EP2010027A2
Application number: EP07720098A
Authority: EP
Inventors: Egon Bräuning
Original assignee: Vitra Patente AG
Current assignee: Vitra AG
Priority date: 2006-04-27
Filing date: 2007-04-27
Publication date: 2009-01-07
Also published as: WO2007124609A3; JP2009534134A; WO2007124609A2; US20090021065A1; CN101384195A

Abstract

The mechanism which is designed for a chair, in particular for a rotatable office chair with a gas spring which is arranged in a vertical manner in the lower frame of said chair and has a telescopically extendable piston rod for adjusting the height of a seat, has the effect that the adjustment of the inclination of the seat is synchronous with the adjustment of the inclination of the backrest. The mechanism has a base (20) which is stationary per se, through which a stationary first rotary shaft (D1) extends and on which a seat support which can be inclined is mounted. A front connecting means (21) which is connected in an articulated manner in a stationary third rotary shaft (D3) on the base (20) and in a moveable fourth rotary shaft (D4) is arranged between the base (20) and the seat support. The mechanism also has a rear connecting means (24) which is connected in an articulated manner in a moveable sixth rotary shaft (D6) at one end and in a further moveable rotary shaft (D5) at the other end. The mechanism contains at least one first spring element (26) which acts between the base (20) and the seat support and is connected in an articulated manner in the fourth rotary shaft (D4). At the other end, this first spring element (26) is connected in an articulated manner in a moveable eighth rotary shaft (D8) whose position can be varied by means of a gear mechanism (25) which can be operated by the user from the outside. The first spring element (26) is advantageously a gas spring which can be blocked by means of a locking element (218) which can be operated by the user and with which the seat and backrest are locked in the inoperative position.

Description

Mechanics for a chair

Field of application of the invention

The invention relates to a chair mechanism, in particular for a rotatable office chair with a vertically arranged in the base gas spring for adjustability of the height of the seat. The chair mechanism causes with the backward inclination of the backrest, which initiates the user by shifting the weight, the seat synchronously lowered backwards.

State of the art

Synchronous mechanisms for chairs are many, e.g. from the patent publications EP 0 592 369 B1, EP 0 839 478 B1, EP 1 039 816 B1, EP 1 358 821 A1 and WO 2005/120291 A1, and have become established as the standard for comfortable work chairs on the market.

Object of the invention

In relation to the prior art, the invention has for its object to propose a further improved chair mechanism that responds sensitively to weight transfers. Another object is to facilitate the adjustment of the bias of the mechanism for less weighty or heavier persons. A next task is to make the mechanics more universal in order to enable different types of connection of a backrest and armrests.

Overview of the invention

The mechanism is intended for a chair, in particular for a rotatable office chair with a vertically arranged in the base gas spring with a telescopically extendable piston rod to adjust the height of a seat. For tilting adjustment of a backrest, the tilting adjustment of the seat is synchronous. The mechanism has a per se fixed base through which a fixed first axis of rotation extends and on which a tiltable seat support is mounted. Between the base and the seat carrier is a front arranged connecting means which is articulated in a fixed third axis of rotation at the base and in a movable fourth axis of rotation. A rear connection means is articulated on the one hand in a movable sixth axis of rotation and on the other hand in a movable further axis of rotation. In the mechanism at least a first, acting between the base and the seat carrier spring element is present, which is articulated in the fourth axis of rotation. The first spring element is articulated on the other hand in a movable eighth axis of rotation, which can be changed by means of an externally operable by the user gearbox in position.

Specific embodiments of the invention are defined below: The transmission is articulated in a fixed second axis of rotation which extends through the base, in the eighth axis of rotation and in a movable ninth axis of rotation. In the rest position with at least in principle horizontally placed seat and vertically upright backrest are the second axis of rotation, the eighth axis of rotation and the ninth axis of rotation at least substantially perpendicular to each other. In the relaxed position with up to a maximum inclined seat and up to a complementary maximum inclined backrest, the eighth axis of rotation moves in the direction of the third axis of rotation in front of the second axis of rotation and the ninth axis of rotation moves in the opposite direction behind the second axis of rotation.

The first spring element is a gas spring with a cylinder and a telescopically extendable piston rod, which is extended furthest in the rest position at the maximum downwardly directed eighth rotary axis and at the maximum upward eighth rotary axis is retracted furthest in the relaxed position. By means of an intermediate piece, the piston rod is articulated in the fourth axis of rotation.

Within the mechanism are pairwise spring units positioned, which are supported on the one hand in a bearing of the base and on the other hand below bearing strips in bearing blocks, the bearing strips are attached from both sides to the base. The bearing strips are preferably made of plastic and bil- thus with the attached, preferably metallic components self-lubricating bearings.

The front-side connecting means is designed as a plate-shaped lever through which the third and fourth axes of rotation extend. The rear connecting means comprises a sixth axle rod and a sleeve piece or a sixth axle rod connected thereto by arms and a seventh axle rod connected thereto by arms, through which the associated fifth, sixth and seventh axes of rotation extend.

At the first axis of rotation, a back support may be hinged within the base or a pair of uprights externally attached to the base to secure the backrest thereto. The bearing strips have pins for penetration into the front lever and the intermediate piece. In addition, the bearing rails have bearings for receiving the ninth axle rod, which penetrates the transmission, and for receiving the sixth axle rod.

For selectively switchable blocking of the gas spring, a user-operable locking element is arranged on the intermediate piece. The locking element acts on a guided in the piston rod of the gas spring valve rod.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS FIG.

Figure 1A - a chair with the inventive mechanism using spars, in perspective view from below; Figure 1B - the chair according to Figure 1A in the rest position, in side view; Figure 1 C - the chair according to Figure 1A in relax position, in side view;

Figure 2A - the main components of the mechanics, in an exploded view;

Figure 2B - the variants of back straps, back levers and upholstered plates and a pair of spars, in an exploded view; Figure 3A - a base with a plurality of axle rods, in perspective view from above; FIG. 3B - the base according to FIG. 3A, in perspective view from below;

Figure 4A - a front lever, in perspective view from above; Figure 4B - the front lever according to Figure 4A, in perspective view from below;

Figure 5A - a seat support, in perspective view from below; Figure 5B - the seat support according to Figure 5A, in a perspective view from above;

Figure 6A - a transmission with mounted gas spring and bolt, in an exploded view;

Figure 6B - the arrangement according to Figure 6A, partially assembled;

Figure 6C - the arrangement according to Figure 6A, assembled, in perspective view;

FIG. 6D - the arrangement according to FIG. 6C, in a changed perspective;

Figure 7A - a spring unit, assembled;

Figure 7B - the spring unit according to Figure 7A, in an exploded view;

Figure 8A - a pair of bearing strips, in perspective view from below; FIG. 8B shows the bearing strips according to FIG. 8A, in a perspective view from above;

Figure 9A - a back support first variant, with Achsstäben, in perspective view from above;

Figure 9B - a back support second variant, with Achsstäben, in perspective view from above;

Figure 10A - a back lever first variant, with sockets, in perspective view;

Figure 10B - a back lever second variant, with sockets, in perspective view; Figure 1 OC - a pair of spars, in perspective view;

Figure 11A - a pad plate, unadjustable, in perspective view from above;

Figure 11 B - a cushion plate, adjustable, in perspective view from above; Figure 11C - the cushion plate according to Figure 11 B, in perspective view from below;

Figure 12A - a front lever with inserted intermediate piece and gas spring, in perspective view from above;

Figure 12 B - the arrangement according to Figure 12A, in perspective view from below;

Figure 13A - the mechanics in the first Aufbau.hase, with a back support of the first variant;

Figure 13B - the mechanics in zwejte.r Aufbauph.ase, with a back support of the first variant;

Figure 13C - the mechanics in third _. At construction stage, with a back support of the first variant;

Figure 13D - the mechanics in yjerter _. Build-up phase, with a back support and a back lever each first variant;

Figure 13E - the mechanics in fifth. Build-up phase, with a back support and a back lever each first variant;

Figure 13F - the mechanics in the sixth construction phase, with a back support and a back lever each first variant;

FIG. 13G - the arrangement according to FIG. 13F, in a changed perspective;

FIG. 13H - the arrangement according to FIG. 13F, in perspective view from below;

FIG. 14A shows the mechanism with a back support of the second variant and a back lever of the first variant;

FIG. 14B shows the arrangement according to FIG. 14A, with the seat support completed, in perspective view from above; Figure 14C - the arrangement according to Figure 14B, with a backrest completed, in perspective view from above; Figure 14D - the arrangement according to Figure 14C, in perspective view from below;

Figure 15A - the mechanism with a back lever second variant and a pair of spars, in an exploded view;

Figure 15B - the arrangement according to Figure 15A, assembled;

Figure 15C - the arrangement according to Figure 15B, completed with a seat support, in perspective view from below;

FIG. 16A shows the mechanism with a back support of the second variant, in the rest position as a functional principle in vertical section;

FIG. 16B shows the arrangement according to FIG. 16A, in offset vertical section;

FIG. 16C shows the arrangement according to FIG. 16A, in a again offset vertical section;

Figure 16D - an axis diagram, in rest position;

FIG. 17A - the arrangement according to FIG. 16A, in relax position as a functional principle in vertical section;

FIG. 17B shows the arrangement according to FIG. 17A, in offset vertical section;

FIG. 17C shows the arrangement according to FIG. 17A, in a again offset vertical section;

Figure 17D - an axis diagram, in relax position; and

Figure 18 - a superimposed axis scheme of rest and relaxation position.

embodiment

The detailed description of an embodiment of the inventive mechanism and its function will be described below with reference to the accompanying drawings. The following definition applies to the entire further description. If reference numerals are included in a figure for the purpose of graphic clarity, but are not explained in the directly associated description text, reference is made to their mention in the preceding description of the figures. In the interests of clarity, the repeated designation of components in subsequent figures is generally dispensed with, as long as it is clearly recognizable in the drawing that they are "recurring" components.

FIGS. 1A to 1C The mechanism 2 according to the invention is placed on a vertical gas spring 12 which, with its standpipe 11, is inserted in a leg 10, which is typically provided with bottom elements 13, in particular in roll form. The star-shaped foot 10 forms with the standpipe 11, the Höhengasfeder 12 and the bottom elements 13 a base 1. The upper end of the Höhengasfeder 12 inserted in a basically cup-shaped base 20, which is the lowest component of the mechanism 2 and the seat carrier set thereon 22 takes up. A plate-shaped front lever 21, into which a locking element 218 projects, is hinged on the one hand to the front area of the base 20 and, on the other hand, underlies the front area of the seat support 22. One side of the seat support 22 projects a first lever 31 for adjusting the preload of the mechanism 2, while after the other side, a second lever 32 for adjusting the seat depth of the seat 4 and a third lever 30 for actuating the Höhengasfeder 12 depart. The seat 4 consists essentially of a lower pad plate 40 and the pad 46 disposed thereon. In the embodiment shown on both sides of the mechanism 2 from the outside in each case a spar 6 hinged, which extends angled upwards and each carrying a backrest support 71 to which a Armrest 7 is attached to the upper pad 70. Between the spars 6, the backrest 5 is added.

In the rest position according to Figure 1 B, the top of the seat 4 is in the quasi-horizontal seat tilt So and the backrest 5 has the associated almost vertical backrest inclination RQ. In the relaxation position according to FIG 1C, the upper side of the seat 4 has moved into the maximum seat inclination S _max , and the backrest 5 has assumed the maximum backrest inclination R _m ax in synchronism therewith. The inclination of the seat 4 is thus variable over the seat angle α while the inclination of the backrest 5 varies over the backrest angle β.

FIGS. 2A and 2B

The mechanism 2 consists essentially of the following components: - a base 20 with the two first Achsstäben A1, the bounce 209 and the two caps 2033;

a front lever 21 with the third axle rod A3, the locking member 218, the rocker 219, the adjusting screw 2190 and the bushes 236;

a seat support 22 with the screws 2209; a transmission 25;

a gas spring 26;

- An intermediate piece 27 with the sockets 236;

- two spring units 28;

- two bearing strips 29; a third lever 30 with the rod 300;

a first lever 31 with the rod 310;

a back support 23 of the first variant or a back support 23 "of the second variant with the two first axle rods A1 positioned on the first rotation axis D1, the bushes 236 and the fifth axle rod A5 coming to rest on the fifth rotation axis D5;

a back lever 24 of the first variant or a back lever 24 'of the second variant with the fourth bushings 246, the sixth axis of rotation D6 extending parallel to this and the seventh axis of rotation D7 extending through the back levers 24, 24'; an optional pair of bars 6 through which the first axis of rotation D1 and the seventh axis of rotation D7 extend; and - A cushion plate 40 without seat depth adjustment or a cushion plate 40 'with seat depth adjustment.

FIGS. 3A and 3B The base 20 initially has a bottom 200, a first side wall 201 adjoining thereto, an opposite second side wall 202, a front wall 203 and the rear centrally positioned cone receptacle 204, which is revolved in a U-shape by the middle wall 205. From the bottom 200, in front of the cone receptacle 204, are raised two elevated bearing webs 206, each with a hole 2060 for receiving the second axle rod A2, through which the second axis of rotation D2 extends. Between each bearing bar 206 and the adjacent thereto side wall 201,202 is a bearing 207, which is formed from the bottom 200 rising, hollowed-out ribs, which end well below the holes 2060. At the two rear extensions 2013,2023 of the side walls 201,202 sets behind each with a distance an inner wall 208, so that between the extensions 2013,2023 and the side walls 201,202 each creates a cavity. Stabilizing transverse webs 2051 extend between the center wall 205 and the cone seat 204 with its inner cone 2040. At the projection of the extensions 2013,2023 there is in each case a hole 2012 which is aligned with a hole 2050 in the middle wall 205, in turn a hole 2080 in FIG the inner wall 208. The hole 2080 is followed by an eye 2081 which lies in the respective cavity between the inner wall 208 and the associated side wall 201, 202. The mutually aligned holes 2012,2080,2050 form with the eye 2081 each have a receptacle for the two first Achsstäbe A1 on the first axis of rotation D1. Between the cone seat 204 and the second side wall 202, a block-shaped support 2082 is positioned.

Towards the front, the two side walls 201, 202 each terminate in a spring 2031 between which the front wall 203 lies. Through the two front eyes

2031 extends in each case a mutually aligned hole 2032 for receiving the third axle rod A3, which comes to rest on the third axis of rotation D3. For the outer closure of the holes 2032, with inserted axle rod A3, a cap 2033 is provided in each case.

Figures 4A and 4B The plate-shaped front lever 21 consists essentially first of the bottom 210, the angles thereto attaching sidewalls 211, which have a triangular cut in principle, and on the underside of the bottom 210 mutually parallel two longitudinal webs 212. On the one hand go the longitudinal webs 212 in each case in a first eye 214 and on the other hand in each case in a second eye 216 via. Between the two first eyes 214 extends an outwardly curved, shell-shaped axle web 213, wherein each eye 214 has a hole 215 and passes through two mutually aligned holes 215, the third axis of rotation D3. Each second eye 216 has a hole 217, both holes 217 are aligned with each other and the fourth axis of rotation D4 extends therethrough. From the region of the second eyes 216, the height of the side walls 211 increases in the direction of the first eyes 214. The bottom 210 has between the two second eyes 216 has a recess 2100, in which the locking member 218 comes to rest.

FIGS. 5A and 5B

The seat support 22 with the bottom 220, the two downwardly extending side walls 221, 222 and the side walls 221, 222 connecting on one side of the rear wall 223 forms the base 20 is a kind of cover. The side walls 221,222 set perpendicular to the bottom of the bottom 220, offset from the outer edges inwardly to. Parallel to the rear wall 223 rises from the bottom of the bottom 220 a stop bar 226 lesser height and further 220 reinforcing ribs 225 are provided between the side walls 221,222 and the underside of the bottom. A multiplicity of first screw holes 229 extend through the bottom 220, and a counter contour 2299 rises above the rear wall 223 on the upper side. At an inwardly offset edge there is a grid 227 on the upper side of the base 220. The first side wall 221 has a passage 224. In the two strip-shaped outer areas of the bottom 220 has - from the front in the direction the back wall 223 - each symmetrically a second screw hole 228, an upstanding threaded cone 2291 and behind the passage 224, a third screw hole 2292, another second screw hole 228, another threaded cone 2291 and finally still a third screw hole 2292.

FIGS. 6A to 6D

The transmission 25 consists of a first housing part 250, a second housing part 251, a drive element 252, a spindle screw 253, an eighth axis rod A8 with the internal thread 254 and two second sockets 255 and two third sockets 256. The housing part 250 extends horizontally first axle hole 2502 and the second axle hole 2503, which are in alignment with the ninth axis of rotation D9 and the second axis of rotation D2. From the housing part 250, a cylindrical projection 2500 extends horizontally outwards, which has a central passage 2501. There are screw holes 2507 on the inside. The second housing part 251 has through bolt holes 2517 and a first, located on the axis of rotation D9 axle hole 2512 and a second, lying on the rotation axis D2 axle hole 2513, which are congruent to the screw holes 2507 and the axle holes 2502,2503. A collar 2514 rises from the inside and underneath is a hollowed-out guide 2515 and beneath it a slot 2516.

In the assembled state, the screw holes 2507, 257 serve to connect both housing parts 250, 251. The first bevel gear 2524 of the drive element 252 lies in the bearing recess 2504 and its shaft 2520 protrudes into the cylinder projection 2500, so that the internal polyhedron 2521 in the shaft 2520 is accessible via the passage 2501. The collar 2514 holds the drive element 252 in position and the second bevel gear 2534 of the spindle screw 253 engages the first bevel gear 2524, wherein the spindle screw 253 is located in the guide 2515 and engages with its external thread 2535 in the internal thread 254 of the Achsstabes A8. The axle rod A9 penetrates the axle holes 2502, 2512 and projects out of the housing parts 250, 251, respectively. The third sockets 256 are each externally inserted into the second axle holes 2503,2513 plugged. The gas spring 26 to be guided on the gear 25 in the eighth axis of rotation D8 has at one end a U-shaped clamp part 261, in whose through holes the axle rod A8 is inserted, which is thickened in the middle and has a threaded pin 2540 on the outside. On each threaded pin 2540, a second bushing 255 is screwed, so that the clamp part 261 is clamped, wherein in each case a socket head 2550 in the slot 2516 or in the complementary slot of the first housing part 250 comes to rest. To the clamp member 261 sets the elongated cylinder 260 of the gas spring 26, from which the piston rod 262 exits, which is attached thereto by means of a connector 263 which belongs to the intermediate piece 27.

The intermediate piece 27 initially has a horizontal bolt 274, on each of which a blind hole 270 is present on both sides. In the extension direction of the two blind holes 270, the fourth axis of rotation D4 runs. Center of the bolt 274 extends a fork segment 271 downwards, which has at the free ends of the two wings parallel to each other two holes, which serve to receive the first and second axle pins 272.273. With the second axle pin 273, a rocker 219 is tiltably fixed between the two wings of the fork segment 271, within a recess. The rocker 219 protrudes into a centrally positioned recess on the bolt 274 and ends in alignment with the piston rod 262. By means of the first axle pin 272, which also extends through the fork segment 271, the locking element 218 is tiltably mounted. At the end projecting into the bolt 274, the rocker 219 is provided with an adjusting screw 2190 which is directed towards the end of the piston rod 262 of the gas spring 26 and presses thereon on the valve rod guided in the piston rod 262, which is spring-biased.

FIGS. 7A and 7B

A spring unit 28 consists of a first spring guide 280, a second spring guide 285 and the coil spring 289 received therebetween. On the first spring guide 280 there is a first bearing head 281 against which the first shaft 282 attaches, from which a pin 283 extends axially. The second spring guide 285 has a second bearing head 286, to which the second Shank 287 attaches, which has an axial hole 288. In the assembled state, the pin 283 is axially movable in the hole 288 and the ends of the coil spring 289 sit on the shafts 282,287. At the maximum compression of the spring unit 28, the leading edges of the shafts 282,287 abut each other and thus limit the further spring travel. The outer ends of the bearing heads 281, 286 are rounded, the eleventh axis of rotation D11 extending through the first bearing head 281 and the tenth axis of rotation D10 extending through the second bearing head 286.

Figures 8A and 8B

The existing as a pair of bearing strips 29 - quasi formed as a right and left bearing bar 29 - each have a horizontal bottom 290 and an outside, downgoing side wall 291. Front ends the bearing bar 29 with a first eye 292, the side in a pin approach 2920 merges, of which axially - lying on the fourth axis of rotation D4 - a pin extension 2921 extends. Between the side wall 291 and the bottom 290 reinforcing ribs 2900 and a bearing block 293 are mounted with a bearing recess 2930. At the other end, the bearing bar 29 has a second eye 297 with the horizontally through hole 298 - through this extends the axis of rotation D6 - and the frontal lobes 2970. Before the second eye 297 is located at the bottom of the bottom 290, a third eye 294 the hole 295 through which the rotation axis D9 passes. On both sides of the third eye 294 reinforcing ribs 2900 extend to the side wall 291. In the side wall 291 of the right bearing bar 29 is near the second eye 297, a passage 2910. Near the two outer eyes 292,297 a screw hole 299 in the bottom 290 is present, while the middle eye 294 has a screw hole 299 on both sides. Another screw hole 299 opens on the top of the bottom 290 and extends into the bearing block 293 inside.

Figure 9A

The back support 23 of the first variant is, in principle, a U-shaped sheet-metal part with the bottom 230 and on both sides outside, mutually parallel Abkantun- gene, the side walls 231 form. By the two side walls 231 each extend two mutually aligned front axle holes 232 and rear axle holes 235. When assembling the first sockets 236 are set with its flange side from the outside to the front axle holes 232, the Buchsenschäfte for insertion into the eyes 2981 and recording the Achsstäbe A1 are determined, which come to rest on the axis of rotation D1. Near the axis of rotation D1, a stop 233 is bent out of the bottom 230 upwards. In the bottom 230 are in line with the stop 233 two holes 234. The rear axle holes 235 serve to accommodate the lying on the axis of rotation D5 axle rod A5.

FIG. 9B

The back support 23 'of the second variant is an angle piece with the bottom 230' and on both sides with external, mutually parallel folds which form sidewalls 231 '. An upwardly directed second leg 238 'adjoins a first leg 237'. In the region of the first leg 237 'extending through the two side walls 231' in each case two mutually aligned front axle holes 232 'and rear axle holes 235'. When assembling the first sockets 236 are in turn set with their flange side from the outside to the front axle holes 232 ', wherein the Buchsenschäfte are intended for insertion into the eyes 2981 and receiving the Achsstäbe A1, which come to rest on the axis of rotation D1. At the transition between the legs 237 ", 238 'there is a hole 234' in the floor 230. The rear axle holes 235 'also serve to receive the axle rod A5 harboring the rotary axis D5.

Figure 10A

The back lever 24 of the first variant consists of the axle rod A6, through which the rotation axis D6 extends, and the sleeve piece 240 arranged parallel thereto, wherein the axle rod A6 and the sleeve piece 240 are connected by two mutually parallel, upwardly bent arms 242. Through the sleeve piece 240, a passage 241 and the axis of rotation D5 extends. For insertion into the two-sided, outer mouths of the passage are fourth sockets 246th provided, the flange sides limit the insertion depth of the sockets 246.

1OB The back lever 24 'of the second variant consists of the axle rod A6, through which the rotation axis D6 extends, and the axle rod A7 arranged parallel thereto, wherein the axle rods A6.A7 are connected by two mutually parallel, upwardly bent arms 242'. The ends of the axle rods A6, A7 project beyond the arms 242 ¹ on both sides, the axle rod A7 terminating on both sides as a tapered pin 241 ".

FIG. 10C

The paired spars 6 are divided into a first branch 60 and a second branch 63 bent upward thereof, which has a connection contour 630 for fastening the backrest 5. At the free-ending head 61 a horizontally introduced blind hole 610 is present, the extension of which lies on the axis of rotation D1. Approximately in the middle of the first branch 60 is an inwardly facing pin 62 with the existing blind hole 620 from whose extension lies on the axis of rotation D7.

Figure 11A

This rectangular pad plate 40 is used when not desired seat depth adjustment. At the top of the two longitudinal outer edges each have a deeper gradation 43 is present. On each gradation 43 two threaded cones 44 with internal thread and adjacent holes 48 are present.

Figures 11 B and 11 C This also rectangular pad plate 40 'is used in the desired seat depth adjustment. In the corner areas long holes 41 'are positioned, which have a keyhole-shaped contour on the bottom. Adjacent to the oblong holes 41 "opens on the underside a screw hole 42 '. On the rear narrow side, the cushion plate 40 "has a securing contour 45" for cooperation with the counter contour 2299 on the upper side of the seat carrier 22.

Figures 12A and 12B

At the connected to the gas spring 26 spacer 27 is now hinged on the axis of rotation D4 of the front lever 21, wherein the bolt 274 is in Erstre- ckungsrichtung the axis of rotation D4. The fork segment 271 directed downwards by the bolt 274 and the locking element 218 fixed thereto are arranged partially within the recess 2100 of the base 210 of the front lever 21. In the illustrated position of the locking element 218 this is tilted into the lower switching position, so that the rocker 219 provides clearance, so that the valve rod can move against the receding adjusting screw 2190. As a result, the gas spring 26 is locked. When switching the rocker 219 is pressed with the seated therein adjusting screw 2190 on the valve rod, which shifts against the bias in the direction of the gas spring 26, whereby the lock is released. Both switching states are stable.

FIGS. 13A to 13H This sequence of figures illustrates the successive assembly of the mechanism 2 and the interaction of the components thereof in combination with the back support 23 of the first variant.

First. Structure. (See Fig. 1.3A) The front lever 21 is positioned with the axle web 213 and the two first eyes 214 between the two front eyes 2031 on the base, so that the holes 2032, 215 are aligned with each other and the axle rod A3 can be inserted, whereby the rotation axis D3 comes into operation and the front lever 21 can pivot. To reduce metallic friction, first bushings 236 are positioned between the front eyes 2031 and the first eyes 214 and slid onto the axle rod A3. To cover the inserted axle rod A3, the caps 2033 are pressed into the holes 2032. At the back of the base 20 is between the extensions 2013,2023 the back support 23 with the front axle holes 232 advanced so far inserted that these axle holes 232 are aligned with the holes 2012,2050,2080 and can be inserted from both sides of the Achsstäbe A1 to form the axis of rotation D1. To reduce metallic friction, the first bushes 236 are positioned between the side walls 231 and the inner walls 208 and slid onto the axle rods A1. The back support 23 can now be pivoted about the axis of rotation D1. On the support 2082, the rod 300 of the third lever 30 for actuating the Höhengasfeder 12 is fixed by means of a hold-down 301, wherein the rod 300 projects through the passage 2021 to the outside. Between the bearing webs 206 and in front of the cone seat 204, a bounce part 209 is inserted. In the rest position bounces the stopper 233 against the center wall 205 and thus prevents the forward inclination of seat 4 and backrest. 5

Zweite.Aufbaup.haseχFjgurJ.3B).

The previously assembled transmission 25 with the gas spring 26 mounted and the intermediate piece 27 are positioned between the bearing webs 206 so that the second axle holes 2503, 2513 are aligned with the holes 2060 to insert the axle rod A2. Thus, the transmission 25 is movable about the rotation axis D2. The attached to the gas spring 26 spacer 27 is located between the second eyes 216. To reduce friction bushes 236 between the second eyes 216 and the pin 274 of the intermediate piece 27 are inserted. The attachment of the intermediate piece 27 between the second eyes 216 is explained in Figure 13E.

Third construction phase .. (Figure 1.3C)

In the bearings 207, the two spring units 28 are inserted with their lower second bearing heads 286, so that below the second bearing heads 286 protruding, the axis of rotation D10 is formed and above the first bearing heads 281 protruding, the axis of rotation D11 is prepared. Vjerte construction phase. (Figure 1.3D) _,

To insert the back lever 24 in the back support 23 of the passage 241 are brought into alignment with the rear axle holes 235, so that the axle rod A5 can be inserted. To reduce friction between see the sleeve piece 240 and the side walls 231 jacks 246 used. Thus, the back lever 24 can pivot about the rotation axis D5, while the axle rod A6 of the back lever 24 will form the rotation axis D6.

Fifth Δy.fbauphase (FJaur.1.3E) To the so far preassembled mechanism 2 from both sides of the bearing strips 29 are added. Here, the pin approaches 2920 come to lie in the holes 217 and the pin extensions 2921 each engage in a blind hole 270 on the pin 274 of the intermediate piece 27 a. The both sides of the gear 25 projecting ends of the Achsstabes A9 protrude into the holes 295 of the third eye 294 of the bearing strips 29 inside. The ends of the axle rod A6 from the back lever 24 come to rest in the holes 298 of the second eyes 297. In addition, the first bearing heads 281 of the two spring units 28 are positioned in the bearing recesses 2930 on the underside of the bearing strip 29 and thereby yield the axis of rotation D11. Particularly advantageously, the bearing strips 29 are made of plastic, while the components connected thereto are metallic, so that virtually self-lubricating bearing points are formed.

Sixth on ^

Finally, the seat support 22 is mounted, wherein the Versch rob take from above through the lying in the inner region in the bottom 220 first screw holes 229, the distribution is congruent with the screw holes located in the bearing strips 29 299. To actuate the transmission 25 for setting the bias of the mechanism 2, the rod 310 (see Figure 2A) was pushed into the passage 2501 and further into the internal polygon 2521. Through the side hole 224 in the seat support 22 pushes the first lever 31 on the outwardly projecting end of the rod 310 to bring by rotation thereof, the drive member 252 in rotation, which entrains the spindle screw 253 and thereby the Achsstab A8 upwards or downwards move and ultimately to adjust the leverage ratios in the mechanism 2. At maximum lowered axis of rotation D8, the chair is set to lighter persons, while the maximum high-rotation axis D8 is the setting for heavier persons.

The paired on each side of the seat support 22 third screw holes 2292 are reserved for the optional attachment of armrests 7. The pairwise existing second screw holes 228 are used for screwing from below with the non-adjustable pad plate 40. When installing an adjustable in the seat cushion pad 40 "screws are screwed from above into the threaded cone 2291, the screw heads are inserted through the keyhole-shaped slots 41 'on the underside of the cushion plate 40' and thus allow a displacement of the cushion plate 40 '.

Figures 14A to 14D

In this sequence of figures, the use of the back carrier 23 "second variant is shown, which is also installed in combination with the back lever 24 first variant. The linkage on the axes of rotation D1, D5 is identical in principle, but from the back support 23 'the upwardly projecting second Leg 238 "is used to attach the backrest 5, while the back support 23 first variant, the connection to the backrest 5 is done with the straight expiring end.

FIGS. 15A to 15C

An alternative attachment of the backrest 5 provides the use of the spars 6 in conjunction with a back lever 24 'second variant. Here, the outer ends of the axle rod A6 are also received in the holes 298 of the second eyes 297 in the bearing strips 29 and form there the axis of rotation D6. The outer pin 241 'of the Achsstabes A7 stuck with insertion of sockets 246 in the blind holes 620 of the pins 62 on the spars 6 and form the axis of rotation D7. The heads 61 with their blind holes 610 of the Holms 6 are articulated on the rotational axis D1 on the outer sides of the two side walls 201, 202 of the base 20.

FIGS. 16A to 16D The base 20 is fixed in any position except for height adjustment and free rotation on the undercarriage 1. In the rest position, the seat support 22 is in a horizontal position and the backrest 5 approximately in a vertical orientation. The axis of rotation D4 is upstream of the fixed axis of rotation D3 and the front lever 21 assumes a minimum inclination relative to the horizontal. The axis of rotation D11 is upstream of the axis of rotation D10 and the spring units 28 assume a minimum inclination relative to the horizontal. The axis of rotation D9, the fixed axis of rotation D2 and the axis of rotation D8 are in principle perpendicular to each other. The axis of rotation D6 is at the maximum height level above the fixed axis of rotation D1 with the slightest vertical offset to the axis of rotation D5 currently at the maximum height level. At maximum downwardly disposed axis of rotation D8, the piston rod 262 of the gas spring 26 is maximally extended and the lever arm between the axes of rotation D2, D8 also maximum, so that a lower force to the rear by sitting on the chair person to move to the relaxation position is sufficient. If the axis of rotation D8 were maximally upwards, the piston rod 262 of the gas spring 26 would be less extended and the lever arm between the axes of rotation D2, D8 shorter, so that a higher force to the rear through the person sitting on the chair for movement to the relaxed position required would be generated as with a larger body weight.

FIGS. 17A to 17D

In the relaxed position, the seat support 22 rises in front, lowers at the back and moves towards the backrest 5, thus assuming a synchronous inclined position to the reclined backrest 5. This presupposes that the gas spring 26 is in the non-locked switching position, that is, the locking element 218 is tilted upwards. The axis of rotation D4 is less upstream of the fixed axis of rotation D3 and the front lever 21 takes against the Horizontal a maximum inclination. The axis of rotation D11 is slightly upstream of the axis of rotation D10 and the spring units 28 take a maximum inclination relative to the horizontal. The axis of rotation D9 has moved behind the invariable axis of rotation D2, while the axis of rotation D8 is now upstream of the axis of rotation D2. The axis of rotation D6 is located at a minimum height level above the invariable axis of rotation D1 with the greatest vertical offset to the momentarily at the lowest height level axis of rotation D5. The spring units 28 are maximally compressed and the piston rod 262 of the gas spring 26 is retracted at maximum, so that at defined load reduction, the backrest 5 and the seat support 22 with the seat 4 are automatically pushed back into the rest position.

FIG. 18

This axis scheme superimposed between the rest and relaxation position illustrates the invariable axes of rotation D1, D2, D3, which are still drawn in solid black, and the positions of the variable essential axes of rotation D4, D5, D6, D8, D9 which move around them. Not shown here are lying in the spring units 28 axis D11, which also changed. However, hardly changes the lower axis D10, which passes through the spring 28 units. When using a pair of spars 6, the position of the rotation axis D7 changes.

Claims

claims

1. Mechanics (2) for a chair, in particular for a rotatable office chair with a base frame (1) vertically arranged gas spring (12) with a telescopically extendable piston rod for adjustability of the height of a seat (4), wherein: a) to a tilting Adjustment of a backrest (5), the tilting adjustment of the seat (4) is synchronous; b) the mechanism (2) has a per se fixed base (20) through which a fixed first axis of rotation (D1) extends and on which a tiltable

Seat support (22) is mounted; c) between the base (20) and the seat support (22) a front connecting means (21) is arranged, which is articulated in a fixed third axis of rotation (D3) on the base (20) and in a movable fourth axis of rotation (D4); d) a rear connecting means (24,24 ') is arranged, which is articulated on the one hand in a movable sixth axis of rotation (D6) and on the other hand in a further movable axis of rotation (D5.D7); e) in the mechanism (2) at least a first, between the base (20) and the seat support (22) acting spring element (26) is present, which is articulated in the fourth axis of rotation (D4), characterized in that f) the the first spring element (26) on the other hand in a movable eighth axis of rotation (D8) is articulated, which can be changed by means of an externally operable by the user transmission (25) in the position.

2. Mechanism (2) according to claim 1, characterized in that a) the transmission (25) in a fixed second axis of rotation (D2) extending through the base (20), in the eighth axis of rotation (D8) and in a movable ninth rotary axis (D9) is articulated; b) in the rest position with at least in principle horizontal seat (4) and vertical backrest (5) the second axis of rotation (D2), the eighth axis of rotation (D8) and the ninth axis of rotation (D9) are at least substantially perpendicular to each other; and c) in the relaxed position with up to a maximum inclined seat (4) and up to a complementary maximum inclined backrest (5) the eighth

Rotary axis (D8) in the direction of the third axis of rotation (D3) before the second

Rotated axis (D2) and the ninth rotary axis (D9) moves in the opposite direction behind the second axis of rotation (D2).

3. Mechanism (2) according to at least one of claims 1 and 2, characterized in that a) the first spring element (26) is a gas spring (26) with a cylinder (260) and a telescopically extendable piston rod (262); b) the piston rod (262) is extended furthest in the rest position at the maximum downwardly directed eighth axis of rotation (D8) and, with the eighth axis of rotation (D8) maximally raised, is retracted furthest in the relaxed position; and c) the piston rod (262) is articulated by means of an intermediate piece (27) in the fourth axis of rotation (D4).

4. Mechanism (2) according to at least one of claims 1 to 3, characterized in that a) within the mechanism (2) pairs of spring units (28) are positioned, on the one hand in a bearing (207) of the base (20) and supported on the other hand below bearing strips (29) in bearing blocks (293), wherein the bearing strips (29) from both sides to the base (20) are added; and b) the bearing strips (29) are preferably made of plastic and thus self-lubricating with the attached, preferably metallic components

Form bearings.

5. Mechanism (2) according to at least one of claims 1 to 4, characterized in that a) the front-side connecting means (21) is designed as a plate-shaped lever through which the axes of rotation (D3, D4) extend; and b) the rear connecting means (24, 24 ') comprises a sixth axle rod (A6) and a sleeve piece (240) connected thereto via arms (242). or a sixth axle rod (A6) and a seventh axle rod (A7) connected thereto via arms (242 ") through which the associated axes of rotation (D5, D6, D7) extend.

6. Mechanism (2) according to at least one of claims 1 to 5, characterized in that a) on the rotation axis (D1) within the base (20), a back support (23,23 ") or outside of the base (20). a pair of spars (6) can be hinged to attach thereto the backrest (5), and b) the bearing strips (29) have pins (2920, 2121) for penetrating the front lever (21) and the intermediate piece (27) and Bearings (295,298) for receiving the ninth axle rod (A9) which penetrates the gearbox (25) and for receiving the sixth axle rod (A6).

7. Mechanism (2) according to at least one of claims 1 to 6, characterized in that a) for selectively switchable blocking of the gas spring (26) is a user-operable locking element (218) on the intermediate piece (27) is arranged; and b) the locking element (218) acts on a valve rod guided in the piston rod (262) of the gas spring (26).