Patent Application
20200305610
This application claims the priority, under 35 U.S.C. § 119, of German application DE 10 2019 107 745, filed Mar. 26, 2019; the prior application is herewith incorporated by reference in its entirety.
The invention relates to a housing for a tilt mechanism, to a tilt mechanism having such a housing, and to a chair, in particular an office chair, having such a tilt mechanism.
Known mechanisms for office chairs include synchronous mechanisms and tilt mechanisms. The designation synchronous mechanism is understood to mean assemblies in the seat substructure of an office chair, which serve to realize a coupled-together kinematic mechanism that brings about a particular relative movement of the seat and backrest relative to one another. The seat, generally provided with a cushioned seat surface, of the office chair is mounted on the seat support. The backrest support, which customarily extends toward the rear from the actual synchronous mechanism, supports the backrest of the office chair on an upwardly extending arm. The seat support and backrest support are usually coupled together in an articulated manner such that a pivoting movement of the backrest toward the rear—as can be brought about for example by the user of the chair leaning against the backrest—induces a lowering movement of the rear edge of the seat. This is intended to prevent the “shirt riding-up effect”, as it is known, and to enhance sitting comfort. Synchronous mechanisms of this kind often have a very complicated construction and are thus expensive to produce.
By contrast, tilt mechanisms are assemblies of comparatively simple construction in the seat substructure of chairs, in the case of which the backrest support is rigidly connected to the seat support, the seat or the frame of the chair. The resultant seat support/backrest support combination, often embodied in the form of a one-piece seat/backrest shell, is pivotable toward the rear about a pivot axis extending transversely to the chair longitudinal direction when the user of the chair leans against the backrest. Such tilt mechanisms are often used instead of synchronous mechanisms in inexpensive visitor or conference chairs, in order to realize a simple tilting function there. On account of their comparatively simple structure, tilt mechanisms are usually much more inexpensive to produce than the above-described synchronous mechanisms.
It is an object of the invention to provide a chair, in particular an office chair, having a tilt mechanism that is particularly inexpensive to produce.
This object is achieved by a mechanism housing as claimed in the independent housing claim, and by a tilt mechanism as claimed in the independent tilt mechanism claim, and by a chair as claimed in the independent chair claim, respectively. Advantageous embodiments of the invention are specified in the dependent claims.
The invention relates to tilt mechanisms, i.e. to such mechanisms, where the backrest support is rigidly connected to the seat support, the seat or the frame of the chair. In particular, the invention relates to tilt mechanisms, where the backrest support is rigidly connected to a housing for a mechanism. This housing is either a housing in which a seat support is integrated, or a housing which has a seat-support mounting apparatus for rigidly fastening a seat support to the housing. Therefore, there is either a rigid seat support-backrest support combination or a rigid housing-backrest support combination. In both cases, seat support and backrest support form a motion unit. That motion unit is characterized in that there is no relative movement of the seat support and backrest support relative to one another. In other words, seat support and backrest support always move along one and the same movement path.
A basic idea of the invention is, in the case of a tilt mechanism, to separate the seat, or seat support, and backrest, or backrest support, structurally from one another. In this way, a kind of modular design can be realized, in which the housing, as basic building block of the mechanism, can be combined, depending on customer preferences, with different backrest supports, and likewise, if exchangeability is provided, with different seat supports or seats, and, as an optional variant, selectively with different armrests.
As a result of such a modular design of the tilt mechanism housing, it is possible, inter alia, to reduce the storage and production costs, to simplify the assembly processes, and to reduce repair costs, in particular when the backrest supports and optionally the seat supports and armrests, and the corresponding assembly devices, are standard parts, components or connections.
Accordingly, the housing according to the invention for a tilt mechanism for a chair, in particular an office chair, contains a receptacle for a chair column, and a backrest-support mounting apparatus for fastening a backrest support to the housing. As a result, a tilt mechanism housing produced preferably from a plastics material is provided, which at the same time provides a fastening capacity for a back of the chair.
The mechanism housing contains preferably a sear support integrated in the housing. In this variant, the housing serves at the same time as a seat support, i.e. forms the structure supporting the actual seat, in particular the seat cushion.
In an alternative embodiment of the invention, the housing has a seat-support mounting apparatus for fastening a seat support to the housing. In this case, the seat support is thus not an integral constituent of the mechanism housing but can, according to the concept of the modular design, be selected, like the backrest support, from a choice of appropriate parts.
In an optional embodiment, the housing has an armrest mounting apparatus for selectively fastening armrests to the housing.
In order to realize the tilting function, the housing according to the invention contains, according to a preferred embodiment, a suitable pivoting device, by which the housing is pivotable about a pivot axis extending transversely to the housing longitudinal direction, the subsequent chair longitudinal direction. In the mounted state, the housing will thus be pivotable to the rear when the user of the chair leans against the backrest. The type of configuration of the pivoting device is not important in this case. A person skilled in the art is familiar with different ways of providing a suitable pivoting device.
According to a preferred embodiment of the invention, the housing has a spring arrangement for defining the pivoting resistance of the pivoting device and thus of the tilt mechanism. In order to define the pivoting resistance of the mechanism and to return the seat/backrest combination from a pivoted position into the unpivoted normal position, a spring arrangement is installed in the tilt mechanism, preferably in the mechanism housing. Preferably, the housing thus already contains, even without a mounted backrest support, all of the components necessary for configuring the mechanism function, namely tilting counter to the spring force of the spring and returning the seat/back unit into the normal position.
In preferred embodiments, the backrest-support mounting apparatus is embodied in such a way that whether or not the backrest support is fastened to the housing has no influence on the structural integrity of the housing or on the functionality of the tilt mechanism.
According to a particularly preferred embodiment of the invention, the mounting apparatus is embodied such that the backrest support is able to be fastened to the housing and removed from the housing without it being necessary to act on the structural integrity of the housing. In other words, the structural integrity, namely the stability and strength of the housing, is ensured regardless of the mounted state of the backrest support. Furthermore, the housing is entirely functional even without a backrest support fastened thereto, both as regards the mountability on a chair column and as regards the implementability of the mechanism function (tilting and pivoting forward and backward) and the function of the spring arrangement inside the housing. According to an advantageous embodiment of the invention, regardless of the mounting of the backrest support, the housing is closed or substantially closed, i.e., even when a backrest support is not fastened to the housing, foreign bodies and dirt do not get into the interior of the housing. This is preferably achieved in that the mounting apparatus simultaneously forms a part of the outer casing of the housing. In a particularly preferred embodiment of the invention, the backrest-support mounting apparatus contains a receptacle, provided on the housing, for the backrest support, wherein this receptacle is open on at least one of its sides in order to satisfy its receiving function, whereas all other sides of the receptacle, forming the receiving space for the backrest support, are embodied in a closed or substantially closed manner with respect to the interior of the mechanism housing.
A tilt mechanism according to the invention is formed in that a backrest support is fastened to a mechanism housing, as described above, by means of the backrest-support mounting apparatus.
A chair according to the invention is produced in that such a tilt mechanism is positioned on a chair column of a chair base, for example a cruciform chair base.
This results in a chair, in particular an office chair, that is particularly inexpensive to produce.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a tilt mechanism for a chair, in particular an office chair, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
All of the figures show the invention not to scale, but merely schematically and only with its essential parts. Identical reference signs correspond here to elements with the same or a comparable function.
Referring now to the figures of the drawings in detail and first, particularly to
In the example shown in
The mechanism housing 5 is rigidly connected to a backrest support 18, which supports a backrest 20. The interconnected housing/backrest unit forms in this case a movement unit. In order to fasten the backrest support 18, the mechanism housing 5 contains a backrest-support mounting apparatus.
The backrest-support mounting apparatus contains, in the two embodiments shown here by way of example, a receptacle 12, which is attached to the underside 14 of the mechanism housing 5, is open downwardly and toward the rear, as seen in the housing longitudinal direction 9 or chair longitudinal direction, but is otherwise closed, and into which the backrest support 18 can be pushed or inserted with its mounting end and subsequently screwed to the mechanism housing 5 or suitably connected thereto in some other way. For this purpose, the backrest-support mounting apparatus contains suitable connecting elements, such as bores 15 or the like, for producing the screw connections. In other cases, other connecting elements can be used, for example elements for forming latching or snap connections or the like. All connections are preferably embodied in a releasable manner, in order to make it easy to exchange the backrest.
By inserting the backrest support 18 into the receptacle 12, it is possible, depending on the configuration of the connecting elements, to produce a force-fitting and/or form-fitting connection between the backrest support 18 and the mechanism housing 5. Preferably, as illustrated in the figures, a force-fitting screw connection is created.
The shape and size of the receptacle 12 can vary. In the examples illustrated here, the two side walls 16 of the receptacle 12 extend advantageously parallel to one another in the housing longitudinal direction 9 or chair longitudinal direction, while the front wall 17 of the receptacle 12 is formed in a convex manner and extends symmetrically into the receiving space. As a result, particularly good mechanical stability of the connection and reliable force transmission between the two main components of the housing/backrest movement unit are achieved.
In the mechanism housing 5 depicted in
By means of a suitable pivoting device (not illustrated), the mechanism housing 5, together with the mounted backrest support 18 and the backrest 20, is pivotable toward the rear in the pivoting direction 19 about the pivot axis 11 in the chair longitudinal direction 9, counter to the spring force of a spring arrangement (not illustrated) acting between the cone block 7 and the mechanism housing 5, when the user of the chair 1 leans against the backrest 20. The common pivot axis 11, extending transversely to the housing longitudinal direction 9 or chair longitudinal direction, of the mechanism housing/backrest unit is the only pivot axis of the entire mechanism 4. The spring arrangement can comprise one or more suitable spring elements, for example helical compression springs.
In the example shown in
In the example shown in
In both cases, the opening 23, facing toward the rear as seen in the housing longitudinal direction 9 or chair longitudinal direction, of the receptacle 12 is located substantially in line with the rear wall 24 of the mechanism housing 5 and terminates with the rear edge 25 of the housing underside 14. In the mechanism housing 5 according to
In other embodiments that are not shown here, the receptacle 12 is not open on two sides, namely toward the rear and downwardly, but rather the receptacle 12 has only one open side, namely the opening 23. The opening 23 of the receptacle 12 faces for example only toward the rear or only downward. In these cases, the receiving space is always delimited by four side walls 16 and a front wall 17, such that a particularly large contact area (bearing and connecting area) is provided between the backrest support 18 and mechanism housing 5.
The mechanism housing 5 illustrated in
All of the features illustrated in the description, the following claims and the drawing can be essential to the invention both individually and in any desired combination with one another.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102019107745 | Mar 2019 | DE | national |
