Backrest brackets for seating furniture

Abstract

The invention relates to a backrest support for seat furniture. In order to provide a seat furniture with a backrest, wherein particularly simple and reliable installation and removal of the backrest is possible, it is proposed that the backrest support is implemented in two parts, the backrest support has a first support part, and the first support part can be connected to the second support part without tools when a detachable connection is constructed, wherein in the assembled state, the position of the two support parts relative to each other can be fixed without tools by means of a locking structure, wherein the locking structure can be established by engaging a locking element guided on one support part into a receptacle provided on the other support part, wherein the one support part has a toggle lever mechanism configured to move the locking element, wherein when a predetermined force is exceeded, the toggle lever rotation axis can move past the dead center to achieve an over-dead center locking, and the toggle lever mechanism can no longer move without external action.

Description

Technical Field

[0001] The present invention relates to a backrest support for seating furniture, in particular for office chairs. In addition, the present invention relates to a seating furniture, in particular an office chair, with such a backrest support. Background Art

[0002] In order to save shipping costs, seating furniture is usually shipped in a disassembled state. In office chairs, the seat back is usually not installed, but is loosely located at other furniture parts. In the case of frequent changes in the location of the workplace, it may also be necessary to disassemble and reassemble the seat several times.

[0003] Installing the seat backrest on the seat has been relatively complex to date and often requires special tools. If the installation is to be carried out by a layman, it is often not possible for him to tell whether the seat backrest has actually been correctly installed. In the case of an incorrectly installed seat backrest, there is the risk that the seat will be damaged during use or that the user will be injured. Summary of the invention

[0004] The object of the present invention is to provide a piece of seating furniture with a backrest, wherein particularly simple and reliable assembly and disassembly of the backrest is possible.

[0005] This object is achieved by the backrest frame according to the invention or by the seating furniture according to the invention.

[0006] The advantages and embodiments explained below in conjunction with the backrest bracket also apply to the seating furniture according to the invention to the same extent, and vice versa.

[0007] The core idea of ​​the present invention is to implement the backrest bracket in two parts, namely, having a first bracket part, which can be connected to the second bracket part without tools while constructing a detachable connection, wherein, in order to achieve a final installation state, the relative positions of the two bracket parts can be fixed without tools by means of a locking structure that is preferably manually operable, wherein the locking structure can be established by engaging a locking piece guided on one bracket part into a receptacle provided on the other bracket part, wherein the one bracket part has a toggle mechanism constructed to move the locking piece, wherein when a preset force is exceeded, the toggle lever rotation axis can move past the dead point to achieve an over-dead point locking, and the toggle lever mechanism can no longer move without external action.

[0008] By means of the invention, the seat backrest can be installed and removed by a layman, for example the end customer himself and without tools. By means of the invention, it is always ensured that the mechanical connection established between the two bracket parts is reliable.

[0009] In addition to simple, tool-free and reliable installation, the invention allows multiple feedback to the fitter, so that the fitter can understand in a simple and error-proof manner whether the backrest has been installed correctly and reliably.

[0010] Despite the two-part nature of the backrest support, it has been ensured by the present invention that the backrest is installed and maintained without play in the final installed state. Even here, even after multiple disassembly and installation, a connection without play is permanently ensured.

[0011] Preferably, the two support parts are assigned to different seat furniture components. In particular, one support part is structurally assigned to the backrest and carries the backrest in the conventional sense, while the other support part is structurally assigned to the rest of the seat furniture, in particular a base support, a seat support or another support element or frame element of the seat furniture. Here, the individual support parts can again be connected to the seat furniture components assigned to them by means of a detachable connection. Alternatively, however, the support parts can also be connected in one piece or in one piece to the seat furniture components assigned to them.

[0012] According to a preferred embodiment of the present invention, the first support part is implemented as a support part on the backrest side and is therefore connectable to the backrest of the seat furniture or is constructed as an integrated part of such a backrest, while the second support part is implemented as a support part on the base support side and is therefore connectable to the base support of the seat furniture or is constructed as an integrated part of such a base support. However, the present invention is not limited to the division of functions of the backrest support divided into two parts. The first support part can also be implemented as a support part on the base support side, while the second support part is implemented as a support part on the backrest side.

[0013] According to a preferred embodiment of the present invention, the two support parts are implemented so that one support part can be placed in the other support part, wherein the connection surfaces of the two support parts that have been appropriately implemented in this not yet locked installation state, which are butted against each other or abutted against each other, prevent the movement of one support part relative to the other support part in at least one spatial direction. It has been proved to be particularly advantageous that the support part on the backrest side, which is usually easy to operate, is hung into the support part on the basic support side, because the basic support, frame or the like of the seat furniture is mostly connected to the lower structure, such as a seat cross or the like, and is on the ground at the time of installation. The connection surface of the two support parts is then preferably implemented so that the support part on the backrest side installed together with the backrest in the pivot direction is already possible. In other words, the backrest can be brought from its non-pivoted, usually more or less upright position to a position pivoted backward without the connection between the two support parts being disengaged. After this first engagement step, the connection can then be fixed by a locking structure.

[0014] According to a preferred embodiment of the present invention, a locking structure can be established between the two support parts by making a locking member guided on one support part engage in a receiving portion arranged on the other support part. Here, the locking member and / or the receiving portion are implemented so as to establish a sliding wedge connection structure. In this sliding wedge connection structure, the workpieces provided with wedge surfaces move linearly relative to each other in order to engage or disengage the connection. Due to this sliding wedge connection structure, not only a particularly simple and reliable connection of the two support parts can be achieved, but also manufacturing tolerances, such as those occurring when manufacturing the support parts, can be simply and effectively compensated. It has been proven to be particularly advantageous that the engagement of the locking member in the receiving portion is fixed by means of a spring assembly, which has a plurality of spring elements acting on the locking member. In this way, a reliable locking structure can be permanently ensured while maintaining tolerance compensation.

[0015] According to a preferred embodiment of the invention, the engagement of the locking element in the receptacle is carried out by a preferably linear displacement of the locking element, and the locking element has at least one locking element wedge surface which is inclined at an angle α relative to the guideway, whereby in the final mounted state the position of the two support parts relative to one another is fixed. Preferably, the wedge angle α is so flat that the locking arrangement is self-locking, in particular in such a way that the locking element is prevented from being pressed out of the receptacle even during all functional movements of the seating furniture, in particular during pivoting of the backrest.

[0016] According to a preferred embodiment of the invention, the receiving portion has at least one corresponding receiving portion wedge surface, that is, when the locking element is engaged in the receiving portion, it cooperates with the locking element wedge surface and also has a wedge angle α. The relative position of the two workpieces is thus fixed in a force-locking and form-locking manner due to the wedge action.

[0017] According to a preferred embodiment of the invention, the support part has a toggle mechanism which is designed to move the locking element. With the aid of such a toggle mechanism, the locking of the two support parts can be actuated particularly simply and reliably. At the same time, the desired feedback characteristics associated with reaching the final installation state can thereby be realized particularly simply.

[0018] According to a preferred embodiment of the invention, when the toggle lever mechanism is actuated during the locking of the connection, the toggle lever axis of rotation moves past the dead point when a preset force is exceeded, so that the toggle lever mechanism can no longer be moved subsequently without external action. With this over-dead point locking, a very reliable connection can be established, wherein an unintentional release is excluded.

[0019] The invention combines the structural and operating advantages of a toggle lever mechanism with the advantages of a spring arrangement acting on the locking element, so that both permanent tolerance compensation and permanent fixing of the sliding wedge connection can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Embodiments of the present invention will be described in more detail below with the aid of the accompanying drawings. In the accompanying drawings:

[0021] Figure 1 A perspective view showing the backrest bracket from obliquely above before assembly,

[0022] Figure 2 A perspective view showing the backrest bracket from obliquely below before assembly,

[0023] Figure 3 An exploded view of the second bracket portion is shown,

[0024] Figure 4 showing a perspective view of the second bracket part with the handle opened,

[0025] Figure 5 showing a first perspective view of a second bracket portion with a closed handle,

[0026] Figure 6 a second perspective view showing the second bracket portion with the closed handle,

[0027] Figure 7 A view showing the backrest bracket during a first installation step (first longitudinal section),

[0028] Figure 8 A view showing the backrest support after a first mounting step (first longitudinal section),

[0029] Fig. 9 A view showing the backrest support after a first mounting step (second longitudinal section),

[0030] Fig.10 A view showing the backrest support after a second mounting step (second longitudinal section),

[0031] Fig.11 A detailed view of the locking element inserted into the receptacle is shown. DETAILED DESCRIPTION

[0032] All figures do not show the invention to scale, but only schematically and only with essential components of the invention. The same reference numerals correspond to elements with the same or similar functions.

[0033] The invention is explained using a backrest support 2 for an office chair as an example. The backrest support 2 is implemented in two parts. Here, the division is realized transversely to the longitudinal direction 3 of the seat. The seat backrest support 2 has a first support part 4 and a second support part 5, see Figure 1 and Figure 2 The support parts 4 , 5 can be connected to one another in a releasable connection. To achieve the final assembled state, the position of the two support parts 4 , 5 relative to one another can be fixed by means of a preferably manually actuatable locking structure 6 .

[0034] Apart from the axle required for the articulated connection and the spring elements of the spring assembly, all parts of the backrest bracket 2 are made of plastic.

[0035] The first support part 4 is implemented as a support part on the backrest side and is therefore structurally assigned to the backrest 7. The first support part carries the backrest 7 (only schematically shown in the figure). Here, the first support part 4 and the backrest 7 are made of one piece. The second support part 5 is implemented as a support part on the base support side and is therefore structurally assigned to the base support (not shown) of the office chair. In the example shown here, this second support part can be connected to the base support by means of screws, for which purpose screw holes 8 are provided in the support part 5.

[0036] The assembly is carried out in two steps without tools. In the first step, the first support part 4 is inserted into the second support part 5, wherein the backrest support 2 is assembled by this contact engagement or engagement engagement so that the support parts 4, 5 are held together. In order to achieve the final assembly state, in which the support parts 4, 5 are fixedly connected to each other without play, the connection is manually locked in a subsequent second step.

[0037] The detachable connection of the two support parts, which is established by inserting the first support part 4 into the second support part 5, already prevents movement of one support part 4 relative to the other support part 5 in a selected spatial direction. The connecting surfaces of the two support parts 4, 5 are designed here so that after the first assembly step, both support parts 4, 5 no longer need to be held by the assembler. A pivoting movement of the backrest support 2 backwards in the longitudinal direction 3 of the seat is also already possible.

[0038] In the example shown, the side wall 9 extending centrally from the base 8 of the first support part 4 in the longitudinal direction 3 of the seat is inserted obliquely from above into the upwardly open trough-shaped recess 12 provided on the base 11 of the second support part 5, so that the two support parts 4, 5 overlap. The installation is carried out by moving the first support part 4, which is moved by the assembler, towards the fixed second support part 5 in the longitudinal direction 3 of the seat. The installation direction (arrow 10) is thus in Figure 7In order to simplify the installation, the side wall 9 gradually tapers slightly in the direction of the free end 13 of the front part thereof; the recess 12 correspondingly also tapers slightly from the opening 14 of the front side thereof to the direction of the rear end side 15 thereof.

[0039] The side wall 9 has a retaining lug 16 at its front free end 13, which extends transversely to the longitudinal direction 3 of the seat. During assembly, the retaining lug 16 is inserted into a recess 17 provided on the rear end 15 of the recess 12, so that the retaining lug is located below the retaining edge 18 of the recess 17 in the engaged state, see Figure 7 In this way, the first support part 4 is hung into the second support part 5 .

[0040] In the thus mounted state, the upper and lower sides of the two support parts 4, 5 form essentially continuous surfaces of the backrest support 2, which correspond to the surface profile of a one-piece backrest support, see Figures 8 to 10 .

[0041] The lower side 21 of the side wall 9 and the bottom 22 of the recess 12 are provided with contours that correspond to each other substantially and that abut against each other in the installed state. The contour of the bottom 22 comprises a linearly formed retaining edge 23 extending transversely to the longitudinal direction 3 of the seat, which is arranged centrally in the front opening 14 of the recess 12, opposite the rear end 15 of the recess 12. In the installed state, the retaining edge 23 engages in a corresponding retaining groove 24 extending transversely to the longitudinal direction 3 of the seat, which is arranged on the contour of the lower side 21 of the side wall 9 directly before the side wall 9 abuts on the base 8. In this way, the retaining edge 23 and the retaining groove 24 form a pull-out prevention portion. A guide arm 25 extending in the direction of the end side 15 of the recess 12 is arranged to be centrally connected to the retaining edge 23, which guide arm is inserted into an adapted guide receptacle 26 on the lower side 21 of the side wall 9 in the installed state. The guide arm / guide receptacle combination 25 , 26 serves to facilitate the insertion of the first holder part 4 into the second holder part 5 by means of centering guidance.

[0042] In combination with the retaining lugs 16 which rest against the retaining edge 18 and grip the retaining edge 18 from below, the first support part 4 is fixed to the second support part 5 at least in one spatial direction by means of the retaining rim-retaining groove combination 23, 24, which forms a protection against lever movements of the first support part 4 directed opposite to the mounting direction 10. Since the first support part 4 is also inserted into the pot-shaped recess 12, which also laterally limits the movement of the first support part 4 by means of its lateral boundary walls 27, 28, the result is that after the first mounting step, the first support part 4 is already fixed in two spatial directions.

[0043] If at least some of the cooperating connecting surfaces of the two support parts 4, 5 are designed in a wedge-shaped or prismatic manner, it is possible to compensate for mechanical play between the two support parts 4, 5 caused by manufacturing tolerances. In particular, play in the horizontal direction can be eliminated by the wedge-shaped or prismatic retaining edge-retaining groove combination 23, 24. The corresponding cross-sectional profile is Figure 7 and Figure 8 Clearly shown in.

[0044] By means of the locking structure 6 established in the second assembly step, the connection surface of one support part is then permanently abutted against the connection surface of the other support part without gap, thereby achieving a final assembly state in which the first support part 4 is fixed to the second support part 5 in all spatial directions.

[0045] In the mounted state, the relative positions of the two support parts 4, 5 are fixed by the sliding wedge connection. In order to prevent the first support part 4 from being lifted off the second support part 5, the first support part must be locked. For this purpose, a locking element 31 formed on the second support part 5 engages in a receiving portion 32 on the first support part 4. The receiving portion 32 is arranged centrally on the first support part 4 below the side wall 9. A spring assembly 33 acting on the locking element 32 serves to secure the engagement, which spring assembly loads the locking element 31 in the direction of the receiving portion 32.

[0046] Due to manufacturing tolerances when manufacturing the plastic part, the locking element 31 has a mechanical play in the receptacle 32. At the same time, the locking element 31 requires a certain mechanical play so that the locking element can be completely introduced into the receptacle 32. However, in order to mount the seat back firmly and reliably on the seat, the play must be completely eliminated in the final installed state of the backrest support 2. This is ensured on the one hand by the wedge shape of the locking element 31 in combination with the corresponding prismatic shape of the receptacle 32 and on the other hand by the action of the spring assembly 33 on the locking element 31. For this purpose, the locking element 31 and the receptacle 32 are designed so that they establish a sliding wedge connection during engagement. The locking element 31 has at least one locking element wedge surface 34 which is inclined at an angle α (wedge angle 39) relative to the slideway, whereby in the final installed state the positions of the two support parts 4, 5 are fixed to each other in a force-locking and form-locking manner. The receptacle 32 has a corresponding receptacle wedge surface 35, see Fig. 9 and Fig.11 .

[0047] The locking member 31 does not have to be placed in the receiving portion 32 on all sides. Fig.10As shown, it is sufficient that the corresponding wedge surfaces 34, 35 abut against each other. In this case, the guidance of the locking element 31 does not take place in the housing 32. Instead, the locking element 31 is guided in a sliding guide 36 arranged centrally in the base body 11 of the second bracket part 5 and can be moved linearly in the sliding guide. During the establishment of the locking structure, the locking element 31 moves out of the opening 38 of the sliding guide 36 arranged centrally on the end side 37 of the base body 11 and enters the housing 32 until the locking element with its inclined side surface 34 completely abuts against the corresponding wall surface 35 of the housing 32. In other words, the movement of the wedge surface 34 of the locking element 31, which is inclined at an angle α relative to the slideway, is achieved. Here, the locking element 31, which is implemented as a wedge-shaped slide, is guided along the wall of the sliding guide 36, which serves as a guide surface.

[0048] The locking element 31 is permanently loaded with a force acting in the locking direction 30 by means of the spring assembly 33. The locking direction 30 is opposite to the installation direction 10. This force causes a pressure force on the locking element 31, which ensures that the locking element is pressed into the receptacle 32. The spring assembly 33 thus keeps the locking element 31 under load in the final installed state, that is to say during the entire duration of the locking.

[0049] In order to prevent the locking element 31 from being pressed out of the receptacle 32 in the locked state during all functional movements of the seat, in particular when the backrest support 2 is pivoted back and forth from the pivoted rear position in the longitudinal direction 3 of the seat despite the loading of the locking element 31 by the spring assembly 33, the locking element 6 is designed to be self-locking. This is ensured by a very flat wedge angle 39 (α). In order to reliably achieve the self-locking property, the wedge angle 39 cannot exceed a defined maximum value.

[0050] A toggle mechanism 41 is provided on the second support part 5 and is designed to move the locking element 31 , by means of which the locking element 31 is moved out of the second support part 5 and subsequently engages in the receptacle 32 on the first support part 4 to produce a sliding wedge connection.

[0051] The toggle mechanism 41 has, as usual, three rotation points (axes of rotation) and two arms forming a toggle link. The first arm of the toggle mechanism 41 is formed by a handle 42, which is centrally articulated with one side on the base body 11 of the second support part 5. For this purpose, a connecting rod 43 mounted on the handle 42 is pivotably supported on an axle 44 which is fixedly inserted in the base body 11. This articulation of the handle 42 on the base body 11 forms a first rotation point 54 of the toggle mechanism 41, see Figure 3 , Fig.10 and Fig.11 .

[0052] In the example illustrated here, the handle 42 is designed in a plate-shaped manner, but it can also be designed differently while maintaining its functionality in order to be integrated into the design of the seating furniture.

[0053] The handle 42 is articulated with its opposite side to an arm pair 45, 46 forming the second arm of the toggle lever 41. This forms a second pivot point 47 in the middle of the toggle lever mechanism 41, see Fig. 9 By pivoting the handle 42 about the first rotation point 54 , the second rotation point 47 is moved toward the base body 11 of the second support part 5 or away from the base body.

[0054] The two arms 45, 46 of the arm pair are connected at one end to the handle 42 in an articulated manner, and at their other end are fixedly connected to a movable shaft 48, which extends transversely to the locking direction 30 (displacement direction) of the locking element 31. This forms a third rotation point 49 of the toggle lever mechanism 41, see Fig.11 .

[0055] The toggle mechanism 41 is designed so that the handle 42 is in the unlocked state, that is to say even after the first assembly step, in the open position 51, in which the handle 42 protrudes from the second support part 5, see Figure 1 , 2 , 4, 7, 8 and 9. Due to the extended position, the assembler gets a visual signal that the installation is not yet complete.

[0056] When the toggle mechanism 41 is actuated, it moves past its dead center. In this process, a certain resistance must be overcome during the movement of the handle 42. The toggle lever then straightens and the toggle link automatically moves into its end position, which is the stable position of the toggle mechanism 41. The reaching of the dead center locking is thereby signaled to the assembler in a tactile manner and acoustically by snapping into the straightened position of the toggle link. Furthermore, in the final installation state, the handle 42 no longer protrudes from the second bracket part 5, but rests in its closed position 52 against the base body 12 of the second bracket part 5, so that the assembler can also visually check that the final installation state has been reached, see Figure 5 , Figure 6 and Fig.10 .

[0057] The over-dead-center locking of the toggle mechanism 41 is established by moving the toggle axis of rotation 47 through the dead center during the locking of the sliding wedge connection of the two support parts 4, 5. In the dead center, the rotation points 47, 49, 54 and the acting forces are in a straight line. In the over-dead-center position, the rotation point 47 is above the line connecting the rotation points 49, 54, see Fig.10 .

[0058] The spring assembly 33 comprises two spring elements 53 acting in parallel. These spring elements 53 are the spring elements that load the locking element 31 during the existence of the sliding wedge connection. The spring element 53 is supported on the locking element 31 with its root-side end 58, i.e., at the location where the hollow part of the locking element 31 transitions into the locking element head 60 (not shown in the drawings) on the one hand. On the other hand, the spring element 53 is supported with its head-side end 59 on the movable shaft 48, the position of which defines the third rotation point 49 of the toggle mechanism 41.

[0059] In order to provide the locking element 31 with the play in the locking direction 30 required for the formation of the sliding wedge connection and, at the same time, to ensure permanent loading of the locking element 31 while the locking mechanism 6 is in place, the movable shaft 48 is located in a pair of slots 55 designed as shaft guides. The pair of slots 55 is formed in a side wall 56 of the locking element 31, which laterally delimits a hollow section 57 of the locking element 31, which forms the root-side end of the locking element 31 and into which the spring element 53 is inserted, while the solid head-side end of the locking element 31, i.e. the locking element head 60, on which the root-side end 58 of the spring element 53 is supported, is intended to engage in the receptacle 32.

[0060] During the locking process, the two arms of the toggle lever formed by the handle 42 on the one hand and the arm pair 45, 46 on the other hand move relative to one another, wherein the circular movement path of the second rotation point 47 is predetermined by the connection of the handle 42 to the base body 12 with the first rotation point 54. The linear movement path of the third rotation point 49 actuated by the second arms 45, 46 is predetermined by guiding the locking element 31 in the second support part 5.

[0061] During the unlocked position of the support parts 4 , 5 and during the movement of the locking element 31 into the receptacle 32 , the movable shaft 48 is inserted into the pair of elongated holes 55 in the rear position 61 , see Fig. 9 If the dead center is passed and the over-dead center locking is reached, the spring element 53 acting on the locking element 31 loads the locking element 31 and the movable shaft 48, on which the spring element 53 is supported, is located in the pair of elongated holes 55 in the front position 62 moved forward in the direction of the locking element head 60 relative to the rear position 61, see Fig.10 and Fig.11 .

[0062] The spring element 53 ensures that the handle 42 remains in the closed state after the dead point has been crossed. The spring element 53 provides a restoring force on the handle 42, thus keeping the toggle mechanism 41 in its rest position on the other side of the dead point.

[0063] The spring element 53 is designed in such a way that it always acts on the locking element 31 with the minimum required force, regardless of any mechanical play of the locking element 31 in the receptacle 32 that occurs due to manufacturing tolerances.

[0064] In the embodiment illustrated in the drawings, the backrest 7, which can be more easily operated individually, is hung in the seat base (not shown), wherein the handle 42 is arranged as part of the toggle mechanism 41 on the bracket part 5 on the base bracket side. However, the present invention is not limited to this functional division of the backrest bracket 2 divided into two parts. It is also possible to make the exact opposite arrangement. Instead of hanging the first bracket part in the second bracket part, the second bracket part can also be hung in the first bracket part and / or the toggle mechanism can be arranged on the bracket part on the backrest side.

[0065] All features shown in the description and the drawings may be essential to the invention both individually and in any combination with one another.

[0066] These features or combinations of features can each be the basis for an independent invention.

[0067] When describing a combination of features that define the invention, individual features from the description of an embodiment do not necessarily have to be combined with one or more or all other features described in the description of this embodiment; in this respect, each subcombination of features of one or more embodiments is explicitly disclosed together.

[0068] Furthermore, object features of the apparatus may be used to be restated as method features, and method features may be used to be restated as object features of the apparatus. Features restated in this way are implicitly disclosed together.

[0069] Reference numerals list

[0070] 1 (none)

[0071] 2 Backrest bracket

[0072] 3 Seat longitudinal direction

[0073] 4 First bracket part

[0074] 5 Second bracket part

[0075] 6 Locking structure

[0076] 7 Backrest

[0077] 8 Base of the first bracket section

[0078] 9 Sidewall

[0079] 10 Installation direction

[0080] 11. Base of the second bracket part

[0081] 12 recess

[0082] 13 Free end of side wall

[0083] 14 Opening of the recess

[0084] 15 End side of recess

[0085] 16 Retaining lug

[0086] 17 Blank space

[0087] 18. Keep the edges

[0088] 19 (none)

[0089] 20 (none)

[0090] 21 Lower side of side wall

[0091] 22 Bottom of recess

[0092] 23 Keep the edge

[0093] 24 Holding slot

[0094] 25 Guide arm

[0095] 26 Guide accommodating portion

[0096] 27 dividing wall

[0097] 28 dividing wall

[0098] 29 (none)

[0099] 30 Lock direction

[0100] 31 Locking piece

[0101] 32 Accommodation

[0102] 33 Spring assembly

[0103] 34 Locking wedge surface

[0104] 35 Wedge surface of receiving part

[0105] 36 Sliding guide

[0106] 37 End side of the base body

[0107] 38 Opening of sliding guide

[0108] 39 Wedge Angle

[0109] 40 (none)

[0110] 41 Toggle mechanism

[0111] 42 Handle

[0112] 43 Connecting rod

[0113] 44 Handle position fixed axis

[0114] 45 Arm

[0115] 46 Arm

[0116] 47 Second rotation point, elbow rotation axis

[0117] 48 movable axes

[0118] 49 Third rotation point

[0119] 50 (none)

[0120] 51 Open position

[0121] 52 Closed position

[0122] 53 Spring element

[0123] 54 First rotation point

[0124] 55 Long hole pair

[0125] 56 Side wall of locking element

[0126] 57 Hollow part of locking element

[0127] 58 End of root side

[0128] 59 End of the head side

[0129] 60 Locking head

[0130] 61 Rear position of the elbow rotation axis

[0131] 62 Forward position of the toggle lever's axis of rotation.

Claims

1. A backrest support (2) for a seat furniture, the backrest support having a first support part (4) which can be connected to a second support part (5) without tools by forming a detachable connection, wherein: In the assembled state, the positions of the two support parts relative to each other can be fixed without tools by means of a locking structure (6), wherein the locking structure (6) can be established by engaging a locking element (31) guided on one support part into a receptacle (32) provided on the other support part, wherein the one support part has a toggle mechanism (41) configured to move the locking element (31), wherein when a predetermined force is exceeded, the toggle lever rotation axis (47) can move past a dead point to achieve an over-dead point locking, and the toggle mechanism (41) can no longer move without external action.

2. The backrest bracket (2) according to claim 1, wherein: The seating furniture is an office chair.

3. The backrest bracket (2) according to claim 1, wherein: The engagement of the locking element (31) in the receptacle (32) is ensured by means of a spring assembly (33) acting on the locking element (31) using a plurality of spring elements (53).

4. The backrest bracket (2) according to any one of claims 1 to 3, wherein: The engagement of the locking element (31) into the receptacle (32) is achieved by displacement of the locking element (31), and the locking element (31) has at least one locking element wedge surface (34) which is inclined at an angle α relative to the slideway, whereby the positions of the two support parts relative to each other are fixed in the final assembled state.

5. The backrest bracket (2) according to claim 4, wherein: The receptacle (32) has at least one corresponding receptacle wedge surface (35).

6. The backrest bracket (2) according to claim 3, wherein: The toggle mechanism (41) loads a plurality of spring elements (53) of the spring assembly (33) to fix the locking member (31) in the receiving portion (32).

7. The backrest bracket (2) according to any one of claims 1 to 3, wherein: In the assembled, unlocked state, the mutually abutting connecting surfaces of the two support parts prevent a movement of one support part relative to the other support part in at least one spatial direction.

8. A seating piece of furniture, comprising a backrest bracket (2) according to any one of claims 1 to 7.

9. The seating furniture according to claim 8, wherein: The first bracket part (4) of the backrest bracket can be connected to the backrest (7) of the seating furniture or can be constructed as an integrated part of such backrest (7), and the second bracket part (5) of the backrest bracket can be connected to the base bracket of the seating furniture or can be constructed as an integrated part of such base bracket.

10. The seating furniture according to claim 8, wherein: The seating furniture is an office chair.

Images