DE102021112731B4 - Fastening device for chair and chair with fastening device - Google Patents

Abstract

Fastening device (20) for fastening a seat shell (10) to a chair frame (15), the fastening device (20) - a screw (21), - a fastening adapter (22), - a screw nut (26 ), and- an adhesive (25), wherein the fastening adapter (22)- has a recess (22b) for receiving a screw head (21a) of the screw (21),- in the recess (22b) a through hole (22a) for Passing a screw shank (21b) of the screw (21) through the fastening adapter (22), wherein the through hole (22a) is arranged in a bottom section (22c) of the recess (22b), and is dimensioned and designed such that on the one hand the Screw (21) can be arranged with lateral play in the through hole (22a), so that the screw (21) in the through hole (22a) can be inclined to the side relative to the fastening adapter (22), and- on the other hand a lower section of the screw head ( 21a) or an end section of the screw shank (21b) facing the screw head is secured against twisting relative to the through hole (22a), and has a bearing surface (22d) running at least partially around the recess (22b) and on which the adhesive (25) is applicable or applied.

Description

field of invention

The invention relates to a fastening device for fastening a seat shell to a chair frame and a chair with a seat shell and a chair frame, the chair frame being fastened to the seat shell by means of the fastening device according to the invention.

Background of the Invention

Seat shells for chairs that are attached to a chair frame are known from the prior art. For example, from the DE1 114 012 a skid chair is known in which a seat shell is attached to the chair frame by means of fastening screws. In this case, the fastening screws run through the seat shell from the top side of the seat shell. The screws passed through the seat shell are locked on the chair frame by means of screw nuts. The disadvantage here, however, is that the fastening screws are visible on the top of the seat shell. When sitting, these screws can have a negative effect on seating comfort and it can happen that clothing is damaged by the screw heads. On the other hand, dirt can accumulate in the area of the screws or the screw heads, which should be avoided from a hygienic point of view.

Alternatively, it is known to attach the chair frame to the underside of the seat shell by means of screws. This avoids that the screws are visible on the top of the seat shell. However, this type of attachment can only be carried out with seat shells that have an appropriate thickness or strength in order to be able to provide correspondingly deep boreholes for receiving the fastening screws.

In the case of seat shells with a small thickness or thickness, the fastening screws must therefore still be passed through from the top of the seat shell and fastened to the chair frame on the underside of the seat shell with corresponding nuts.

From the U.S. 2,649,136A a fastening device for fastening a seat shell to a chair frame is known, the fastening device comprising a fastening adapter, at least one screw, a screw nut interacting with the screw, and an adhesive. The mounting adapter has a through hole for receiving the screw. On the seat shell side, the fastening adapter has a bearing surface on which the adhesive can be applied or has been applied.

From the KR 10 2005 020 170 A a fastening device for fastening a seat shell to a chair frame is known. The fastening device has a fastening adapter through which a screw can be passed, which in turn is passed through corresponding through-holes on the chair frame. The fastening adapter is locked to the chair frame with nuts.

From the DE 41 14 458 C1 a fastening device for fastening a seat shell to a chair frame is known. The fastening device has a head piece with a flat bearing surface. Furthermore, the fastening device has a locking element which extends from the head piece and can be inserted into an undercut recess in the seat shell. The chair frame is attached to the head piece with a screw.

object of the invention

The object of the present invention is therefore to provide a solution with which, on the one hand, thin or less strong seat shells can be attached to a chair frame without the fastening screws being visible on the top of the seat shell, and on the other hand, a chair frame without any further processing of the seat shell can be attached to the seat shell.

Solution according to the invention

This object is achieved according to the invention by a fastening device for fastening a seat shell to a chair frame and by a chair with a seat shell and a chair frame according to the independent patent claims. Advantageous developments of the invention are specified in the dependent claims.

• - eine Schraube,
• - einen Befestigungsadapter,
• - eine mit der Schraube zusammenwirkende Schraubenmutter, und
• - einen Klebstoff umfasst, wobei der Befestigungsadapter
• - eine Aussparung zur Aufnahme eines Schraubenkopfes der Schraube aufweist,
• - in der Aussparung ein Durchgangsloch zum Durchführen eines Schraubenschaftes der Schraube durch den Befestigungsadapter aufweist, wobei das Durchgangsloch in einem Bodenabschnitt der Aussparung angeordnet ist, und so dimensioniert und ausgestaltet ist, dass
  • - einerseits die Schraube mit seitlichem Spiel in dem Durchgangsloch anordenbar ist, sodass die Schraube in dem Durchgangsloch relativ zum Befestigungsadapter zur Seite hin geneigt werden kann, und
  • - andererseits ein unterer Abschnitt des Schraubenkopfes oder ein dem Schraubenkopf zugewandter Endabschnitt des Schraubenschaftes gegen ein Verdrehen relativ zum Durchgangsloch gesichert ist, und
• - eine zumindest teilweise um die Aussparung herumlaufende Auflagefläche aufweist, auf der der Klebstoff aufbringbar oder aufgebracht ist.

Accordingly, a fastening device is provided for fastening a seat shell to a chair frame, the fastening device

• - a screw,
• - a mounting adapter,
• - a screw nut cooperating with the screw, and
• - comprises an adhesive, wherein the attachment adapter
• - has a recess for receiving a screw head of the screw,
• - has a through hole in the recess for passing a screw shank of the screw through the fastening adapter, wherein the through hole is arranged in a bottom section of the recess and is dimensioned and designed such that
  • - On the one hand, the screw can be arranged in the through hole with lateral play, so that the screw in the through hole can be inclined to the side relative to the fastening adapter, and
  • - On the other hand, a lower section of the screw head or an end section of the screw shank facing the screw head is secured against twisting relative to the through hole, and
• - Has a support surface running at least partially around the cutout, on which the adhesive can be applied or has been applied.

The mounting adapter can be attached to the support surface of the mounting adapter using the adhesive on the underside of the seat shell, the screw itself protruding from the underside of the mounting adapter and the chair frame can thus be attached to the mounting adapter by means of the screw. This makes it possible to attach a chair frame to a seat shell without having to drill holes in the seat shell or without having to pass screws through the seat shell.

The through hole can be designed in such a way that the screw passed through the through hole is secured against twisting relative to the through hole.

It can be advantageous if the through-hole has a three- or multi-sided, preferably four-sided, cross-section and a lower section of the screw head or an end section of the screw shank facing the screw head has a cross-section corresponding to the through-hole.

In one embodiment of the invention, the fastening adapter can be designed in the shape of a plate.

The fastening device can furthermore comprise a deformable washer which can be arranged between the fastening adapter and the chair frame and through which the screw can be passed.

The fastening device can also include an optional connection adapter, which can be arranged between the fastening adapter and the chair frame and through which the screw can be passed, with an end section of the connection adapter facing the chair frame being adapted to the outer shape of the corresponding section of the chair frame.

The connection adapter can also be arranged between the washer and the chair frame.

The fastening device can also include a nut with which the fastening device can be locked on the chair frame.

The adhesive is adapted to attach the fastener to the seat pan, wherein the adhesive may preferably comprise a silane-modified polymer (MS polymer)-based adhesive.

The invention also provides a chair with a seat shell and a chair frame, the chair frame being fastened to an underside of the seat shell by means of a fastening device according to the invention.

character list

• 1 eine erfindungsgemäße Befestigungseinrichtung in einer Explosionsdarstellung relativ zur Sitzschale und zum Stuhlgestell;
• 2 einen Befestigungsadapter einer erfindungsgemäßen Befestigungseinrichtung in einer perspektivischen Ansicht und in einer Schnittansicht;
• 3 eine erfindungsgemäße Befestigungseinrichtung in einer Explosionsdarstellung in einer Seitenansicht;
• 4 die in 3 gezeigte erfindungsgemäße Befestigungseinrichtung in einer Ansicht von vorne;
• 5 eine erfindungsgemäße Befestigungseinrichtung in einer Schnittansicht, die an einem als Rundrohr ausgestalteten Stuhlgestell angeordnet ist; und
• 6 eine erfindungsgemäße Befestigungseinrichtung, die an einer Befestigungsplatte des Stuhlgestells angeordnet ist.

Further details and features of the invention result from the following description in conjunction with the drawing. Show it:

• 1 a fastening device according to the invention in an exploded view relative to the seat shell and the chair frame;
• 2 a fastening adapter of a fastening device according to the invention in a perspective view and in a sectional view;
• 3 a fastening device according to the invention in an exploded view in a side view;
• 4 in the 3 fastening device according to the invention shown in a front view;
• 5 a fastening device according to the invention in a sectional view, which is arranged on a chair frame designed as a round tube; and
• 6 a fastening device according to the invention, which is arranged on a fastening plate of the chair frame.

Detailed description of the invention

1 shows a section of a seat shell 10 of a chair, which is attached or will be attached to a chair frame 15 by means of an attachment device 20 according to the invention. Only a section of the chair frame 15 is also shown here, this section of the chair frame 15 being designed as a round tube.

As will become clear below, this type of attachment according to the invention is characterized in that even seat shells 10 that have a small strength or thickness can be securely and stably attached to a chair frame 15 without 10 fastening screws being visible on the top of the seat shell are. Boreholes in the seat shell 10 for passing through such fastening screws can therefore be dispensed with. Also on the underside of the seat shell there is no need to drill holes for mounting screws. The stability of the seat shell is not affected by drill holes.

The fastening device 20 comprises at least one screw 21, a fastening adapter 22 and a nut 26.

The attachment adapter 22 can have a plate-like shape, as in 2 shown. However, the attachment adapter 22 is not limited to this plate-like shape. Rather, other basic shapes can also be provided, provided that a corresponding recess for receiving a screw head is provided on the upper side of the fastening adapter 22, as can be seen from the following description.

The fastening adapter 22 has a recess or a recess 22b in which the screw head 21a of the screw 21 can be accommodated as completely as possible, so that the screw head 21a does not protrude from the upper side of the fastening adapter 22 . This means that the depth of the recess or depression 22b corresponds approximately at least to the height of the screw head 21a of the screw 21.

A through hole 22a through which the screw 21 is passed from top to bottom is provided at the bottom or bottom portion 22c of the recess 22b. After passing the screw 21 through the through hole 22a, the screw head 21a rests on the bottom portion 22c of the recess or depression 22b.

The through hole 22a is dimensioned so that the screw 21 in the through hole has lateral play, i.e. the screw 21 can be tilted sideways in the through hole. Due to this lateral inclination of the screw 21 relative to the attachment adapter 22, tolerance inaccuracies when attaching the seat shell 10 to the chair frame 15 can be compensated. In addition, bulges on the underside of the seat shell 10 can also be compensated for by this lateral inclination.

The fastening adapter 22 has a support surface 22d running around the recess or recess 22b, which faces the underside 11 of the seat shell 10 when the fastening adapter is fastened to the underside 11 of the seat shell 10 . To attach the attachment adapter 22 to the underside 11 of the seat shell 10, an adhesive 25 is applied to the bearing surface 22d. After passing the screw 21 through the through hole 22a so that the screw head 21a is in the recess or recess 22b, and after applying the adhesive 25 to the bearing surface 22d, the fastening adapter 22 is fastened to the underside 11 of the seat shell 10, i. glued.

Tests have shown that an adhesive based on silane-modified polymers (MS polymer adhesive) is particularly advantageous, with both a 1-component and a 2-component MS polymer adhesive being able to be used.

Alternatively, a PU hotmelt adhesive can also be used.

After the fastening adapter 22 has been glued to the underside 11 of the seat shell 10, the screw 21 is mounted with lateral play in the fastening adapter 22 or in the through-hole 22a of the fastening adapter. The through-hole 22a and a lower section of the screw head 21a or a section of the shank 21b of the screw 21 facing the screw head 21a are designed here in such a way that the screw in the through-hole 22a has lateral play, but the screw 21 itself simultaneously against a Twisting relative to the mounting adapter 22 is secured.

After the fastening adapter 22 has been fastened or glued to the underside 11 of the seat shell 10 , the shank 21b of the screw 21 protrudes from the underside of the fastening adapter 22 . This protruding section of the shank 21b of the screw 21 is then pushed through into a correspondingly dimensioned drill hole in the chair frame 15 and screwed with a screw nut 26 from below. After fastening the screw with the screw nut to the chair frame 15, the seat shell is with the chair connected to frame 15 without having to drill holes in the seat shell for the passage of screws.

The entire attachment of the seat shell to the chair frame does not require drilling or milling, as the fastening device 20 is glued to the underside 11 of the seat shell 10 .

Optionally, a flexible or deformable washer 23 can be arranged between the attachment adapter 22 and the chair frame 15, which washer also has a through hole for the screw 21 to pass through. The washer 23 is preferably deformable so that it can deform when the fastening device 20 is fastened to the chair frame 15 and can thus adapt to the shape of the chair frame 15 and/or to the shape of the underside of the fastening adapter. The washer 23 is preferably made of a plastic.

In a further embodiment of the invention, a connection adapter 24 can be provided between the fastening adapter 22 and the chair frame 15, the lower section of which is adapted to the shape of the chair frame 15. This connection adapter also has a through hole for the screw 21 to pass through.

In a further embodiment of the invention, both the flexible washer 23 and the connection adapter 24 can be provided, so that the flexible washer 23 is pressed between the fastening adapter 22 and the connection adapter 24 when the fastening device 20 is screwed on, as shown in FIG 5 shown.

Furthermore, a cover 30 can be provided with which the nut 26 can be covered. The cover 30 serves on the one hand to hide the nut 26 optically. On the other hand, the cover serves as a stack protector, that is, as a cover that prevents scratching or damage to the seat surface of the chair underneath when chairs according to the invention are stacked. It is advantageous here if the cover 30 consists of a soft but nevertheless stable plastic.

This cover can be provided in all of the embodiments of the invention shown here.

2 shows an embodiment of a fastening adapter 22 of a fastening device 20 according to the invention.

The fastening adapter 22 is designed here in the shape of a plate and has a circumferential, overhead contact surface 22d on which the adhesive 25 is applied.

The mounting adapter has a round base here. However, the base surface can also have any other shape, as long as it has a support surface 22d running all the way round at least in sections for applying the adhesive 25 .

A recess or recess 22b is provided in the center of the fastening adapter 22, which is dimensioned in such a way that the screw head 21a of the screw 21 can be completely accommodated therein. A through hole 22a is provided on the bottom section 22c of the recess 22b, through which the screw can be passed until the screw rests with its screw head 21a on the bottom section 22c. As explained above, the through hole 22a is dimensioned in such a way that the screw passed through the through hole can be inclined against the fastening adapter 22 . At the same time, the through hole 22a is also designed such that the screw passed through the through hole 22a is secured against twisting relative to the fastening adapter 22 .

A substantially cylindrical wall is provided here between the circumferential bearing surface 22d and the through-hole 22a, so that one or more depressions are formed between the bearing surface 22d and this wall, into which adhesive can also be introduced.

The attachment adapter 22 can be made of a stable plastic.

3 and 4 show the in 1 Fastening device shown in a side view and in a view from the front, each in an exploded view.

It is clearly visible in 3 the inclination of the fastening adapter 22 relative to the screw 21. By mounting the screw 21 with play in the through hole 22a of the fastening adapter 22, the inclination of the fastening adapter 22 can be adjusted so that the fastening adapter 22 with its contact surface 22d is largely flat on the underside 11 of the Seat shell 10 rests.

The screw nut 26 is designed here as a sleeve nut that can be inserted on the underside of the tubular chair frame 15, as shown in FIG 5 shown.

5 shows the arrangement of a fastening device 20 according to the invention on the underside 11 of a seat shell 10 and on a tubular chair frame 15.

The flexible washer 23 and the connection adapter 24 are arranged between the fastening adapter 22 and the tubular section of the chair frame 15, with the underside or the lower section of the connection adapter 24 being adapted to the shape of the chair frame. When the nut 26 is tightened, the flexible washer 23 is pressed between the attachment adapter 22 and the connection adapter 24 .

6 shows the arrangement of a fastening device 20 according to the invention on the underside 11 of a seat shell 10 and on a receiving plate 17 which is fastened to a chair frame 15.

Since the mounting plate 17 is designed to be essentially flat in the area of the fastening adapter 22, the connection adapter 24 can be dispensed with here. With the help of the flexible or deformable washer 23, which is arranged between the fastening adapter 22 and the receiving plate 17, the gap between the fastening adapter 22 and the receiving plate 17, which has a specific angle, can be compensated. After the screw nut has been screwed onto the screw 21 , the receiving plate is firmly connected to the fastening adapter 22 so that the chair frame 15 is fastened to the underside 11 of the seat shell 10 via the fastening device 20 .

Nevertheless, it can be advantageous, even with the in 6 shown embodiment of the invention to provide a connection adapter 24. With a connection adapter, the inclination of the seat shell relative to the chair frame can be adjusted or adjusted in a corresponding configuration. This means that different inclinations of the seat shell relative to the chair frame can be realized with different connection adapters. For example, the connection adapters can be wedge-shaped or trapezoidal.

Also the in 5 The connection adapter 24 shown can be provided with an appropriate configuration to set or adapt the inclination of the seat shell relative to the chair frame.

In both cases it has proven to be advantageous that the through hole 22a and the screw 21 are designed in such a way that the screw is mounted in the through hole with play.

The solution according to the invention makes it possible to dispense with bores or other millings in the seat shell in order to accommodate fastening screws for fastening the seat shell to a chair frame. The surface of the seat pan and in particular the upper side of the seat pan remain in an intact condition. An attachment of the chair frame to a seat shell is also possible with thin or less strong seat shells. By storing the screw with play in the through hole of the fastening adapter, tolerance inaccuracies can be compensated for so that screwing to the chair frame is guaranteed at all times after the fastening device has been glued to the underside of the seat shell.

Reference List

10

seat shell of a chair

11

Underside of the seat shell 10

15

chair frame

15a

Through hole on the chair frame 15 to accommodate the screw 21

16

Section of the chair frame designed as a round tube 15

17

Mounting plate on the chair frame 15

20

fastening device

21

Fastener screw 20

21a

Screw head of screw 21

21b

Shaft of screw 21

22

Fastening adapter of the fastening device 20

22a

Through-hole on/in the mounting adapter 22 to accommodate the screw 21

22b

Recess or depression in the fastening adapter 22 for receiving a screw head 21a of the screw 21

22c

bottom portion of recess 22b

22d

Mounting surface of the mounting adapter 22

23

Fastener washer/rubber washer/spacer 20

24

Connection adapter of the fastening device 20 for e.g. round tube 16

25

adhesive

26

Screw nut 21

30

cover

Claims (11)

Fastening device (20) for fastening a seat shell (10) to a chair frame (15), the fastening device (20) - a screw (21), - a mounting adapter (22), - a screw nut (26) cooperating with the screw (21), and - an adhesive (25), wherein the attachment adapter (22) - has a recess (22b) for receiving a screw head (21a) of the screw (21), - in the recess (22b) has a through hole (22a) for passing a screw shank (21b) of the screw (21) through the fastening adapter (22), the through hole (22a) being arranged in a bottom section (22c) of the recess (22b). is, and is dimensioned and designed so that - on the one hand, the screw (21) can be arranged in the through hole (22a) with lateral play, so that the screw (21) in the through hole (22a) can be inclined to the side relative to the fastening adapter (22), and - on the other hand, a lower section of the screw head (21a) or an end section of the screw shank (21b) facing the screw head is secured against twisting relative to the through hole (22a), and - Has a bearing surface (22d) running around at least partially the recess (22b) and on which the adhesive (25) can be applied or has been applied. fastening device claim 1 , wherein the through hole (22a) is designed in such a way that the screw (21) passed through the through hole is secured against twisting relative to the through hole. fastening device claim 1 , wherein the through hole (22a) has a three- or multi-sided, preferably a four-sided cross section and wherein a lower section of the screw head (21a) or an end section of the screw shank (21b) facing the screw head has a cross section corresponding to the through hole (22a). fastening device claim 1 , wherein the fastening adapter (22) is designed in the shape of a plate. fastening device claim 1 , wherein the fastening device further comprises a deformable washer (23) which can be arranged between the fastening adapter (22) and the chair frame (15) and through which the screw (21) can be passed. fastening device claim 1 , wherein the fastening device further comprises a connection adapter (24) which can be arranged between the fastening adapter (22) and the chair frame (15) and through which the screw (21) can be passed, with an end section of the chair frame (15) facing the Connection adapter (24) is adapted to the outer shape of the corresponding section of the chair frame (15). fastening device claim 5 and 6 , wherein the connection adapter (24) can be arranged between the washer (23) and the chair frame (15). fastening device claim 1 , wherein the fastening device further comprises a screw nut (26) with which the fastening device can be locked on the chair frame (15). fastening device claim 1 wherein the adhesive (25) is adapted to attach the fastener to the seat pan (10), the adhesive comprising a silane-modified polymer (MS) polymer adhesive. Chair with a seat shell (10) and a chair frame (15), the chair frame (15) being fastened to an underside (11) of the seat shell (10) by means of a fastening device (20), the fastening device (20) between the seat shell ( 10) and the chair frame (15) and wherein the fastening device (20) - a screw (21), - a fastening adapter (22), - a screw nut (26) cooperating with the screw (21), and - an adhesive ( 25). screw (21) through the fastening adapter (22), the through hole (22a) being arranged in a bottom section (22c) of the recess (22b) and being dimensioned and designed such that - on the one hand the screw (21) has lateral play can be arranged in the through hole (22a), so that the screw (21) in the through hole (22a) can be tilted to the side relative to the fastening adapter (22), and - on the other hand, a lower section of the screw head (21a) or one facing the screw head End portion of the screw shank (21b) against twisting relative to the passage hole (22a), and - has a contact surface (22d) running at least partially around the recess (22b), to which the adhesive (25) is applied and to which the fastening device on the underside (11) of the seat shell (10 ) to fix. chair according to claim 10 , wherein the fastening device (20) further according to a claims 2 until 9 is designed.

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