EP3116347B1 - Rotatable item of seating furniture - Google Patents

Description

The invention relates to a seat piece of furniture with a base and a seat unit, wherein between the base and the seat unit a rotary bearing comprising a base-side bearing means and a seating unit side bearing means is provided by means of which the seat unit is rotatable about a vertical axis relative to the base. In this case, the rotary bearing on a switchable blocking device, by means of which the rotational mobility of the storage facilities is mutually blocked.

The invention also relates to a fitting for such a piece of seating furniture.

Generic seating furniture pieces are known from the prior art. These are seat furniture pieces whose seat unit is basically rotatable relative to a base, wherein the base can be both a foot provided for stationary installation and a base portion provided with rollers. The latter is well known in particular office seating furniture. The rotational mobility of the seat unit allows the seated person to rotate the seat unit without twisting the base, thus assuming a seated position with a changed orientation.

The pivot bearing, which is provided for this purpose between the base and the seat unit, is provided in the case of generic seating furniture pieces with a blocking device that the base and the seat unit in a given relative rotational position coupled to each other so that a rotational movement is no longer possible or strong is difficult.

The aforementioned blockability is particularly useful if it is a piece of seating furniture with a stand-up. Such a stand-up aid makes it possible to raise the seat unit in particular by an electric motor, so that getting up from the piece of seating furniture is facilitated. In the phase of getting up is one Rotary movement of the seat unit generally not desired. The blocking prevents when rising, that it comes to falls due to the rotational movement of the seat unit.

A seat piece of furniture according to the preamble of claim 1 and a fitting according to the preamble of claim 11 is for example made GB 2 430 009 A known.

Known designs for creating a switchable blocking device are comparatively expensive. For example, it has been proposed to provide such a blocking device by means of an additional electric motor which can displace a locking member into a position in which it positively locks the seat unit and the base together. In this and other known solutions, however, it is always a disadvantage to note that these are accompanied by rather expensive additional components and in some cases do not provide the desired reliability.

TASK AND SOLUTION

The object of the invention is therefore to develop a generic piece of seating furniture or a fitting for such a piece of seating furniture to the effect that the switchable blocking device is inexpensive and reliable.

This object is achieved by a piece of seating furniture with the features of claim 1 and a fitting with the features of claim 11. The dependent claims define advantageous embodiments of the invention.

According to the invention the object is achieved in that the blocking device has a blocking surface, a torsion spring surrounding this blocking surface and a switching device. Said blocking surface is provided on a first of the two storage facilities. The said torsion spring wraps around this blocking surface and is fastened to a second bearing device and is such that it can be varied depending on the state of stress Inner diameter has. The switching device is coupled to the torsion spring in such a way that the torsion spring can either tension or relax. The torsion spring and the blocking surface are matched to one another such that the torsion spring rests against the blocking surface either in the clamped, compressed or relaxed contracted state, thereby preventing a rotational movement between the bearing devices.

The inventive design of the blocking device thus provides that it has a circumferential blocking surface on which said torsion spring can create a clamping and from which the torsion spring, the blocking surface can be lifted releasing. The blocking surface is a preferably cylindrical surface which is aligned in the direction of the vertical axis. The torsion spring surrounds this blocking surface one or more times. It is of such a nature that, in a tightly strained or relaxed state, it bears in a clamped manner on the blocking surface and thus can not be moved relative to it, and in contrast other other more relaxed or stressed state exerts no or less force on the blocking surface and therefore permits the rotational movement.

The switching device can basically be an electrically operated switching device, which expands or contracts the torsion spring. Preferably, however, the switching device is a mechanical component that provides mechanical coupling with other subcomponents of the seating furniture piece and thus establishes the released and the blocked state of the blocking device in response to the movement of these other parts.

The torsion spring used is such that its inner diameter depends on its state of tension. This is achieved in particular by a torsion spring with in particular helically arranged turns. The cross section through these turns can be circular. However, according to a concrete embodiment, a square or otherwise rectangular shape may be advantageous, since such a shape causes a facilitated rotationally secured clamping and allows surface contact between the inside of the turns and the blocking surface.

The end of the windings is preferably formed by two torque introduction sections whose relative position in the circumferential direction determines the state of stress. In particular, the ends of these turns can be directed radially or obliquely outwards, as is usual with leg springs. The use of commercial leg springs is advantageous in view of the low cost of the blocking device.

In principle, a design is conceivable in which, to change the state of stress in the torsion spring, both torque introduction sections of the same torsion spring are displaced away from one another or toward one another relative to the second bearing device. However, if the torsion spring is not fixedly connected to the second bearing device with any spring portion, trouble-free operation is more difficult to ensure. It is therefore advantageous if one of the torque introduction sections is fixed immovably to the second bearing device in the circumferential direction. Thus, a relative movement of the torque introduction sections relative to one another is achieved in that that not immovably attached to the second bearing means torque introduction portion of the torsion spring is displaced in the circumferential direction. Tilting of the spring is not to be expected by the one-sided fixed clamping.

As regards the configuration and number of preferably metallic torsion springs, it is provided as a minimum that the one or more torsion springs together loop around the blocking surface over an angle of at least about 360 ° (± 15%). In the blocking state, the blocking surface is thus clamped at least almost circumferentially by the torsion spring or the torsion springs. Particularly advantageous embodiments are considered in which the torsion spring or the plurality of torsion springs wrap around the blocking surface over an angle of approximately 1080 ° (± 15%) or 1800 ° (± 15%). It is therefore Gesamtumschlingungswinkel that provide that the blocking surface is looped about three times or about five times.

Depending on the configuration of the torsion spring and connection of the torsion spring, the tension in the torsion spring provided for producing or releasing the blocking state also leads to a torque acting in the circumferential direction, which is not desired. It is therefore of advantage if an even number of torsion springs, in particular two torsion springs, are used, which are tensioned or relaxed relative to the circumferential direction during simultaneous tensioning or simultaneous expansion in opposite directions so that their torque acting in the circumferential direction is compensated in each case becomes.

Based on the aforementioned wrap angles, it is particularly advantageous if these two torsion springs wrap around the blocking surface over an angle of approximately 540 ° (± 15 °) or approximately 900 ° (± 15 °), ie approximately one and a half times or two and a half times ,

If only one torsion spring is used, there is a risk of tilting the same, in particular if the torque introduction sections of this torsion spring are offset relative to one another in relation to an axial direction. In such a case, it is therefore advantageous if above and below the torsion spring plastic sleeves or the like are provided which cause an axial positional fixation of the torsion spring and prevent tilting of the torsion spring.

The switching device preferably has a switching slide, which is axially movable along the first or second bearing device guided by a guide. This shift carriage is operatively coupled to the torsion spring or the torsion springs such that the axial displacement of the shift carriage causes a tensioning or relaxing of the torsion spring and thus blocking or releasing the blocking device.

The storage of the shift carriage on the first or second bearing device can be formed in the simplest case by a slot with arranged therein slider, in particular in the form of screws. The displacement of the shift carriage can in particular be effected indirectly by a displacement of other subcomponents of the piece of seating furniture. In principle, however, a direct electrical drive of the shift carriage is possible.

The interaction between the shift carriage on the one hand and the at least one torsion spring on the other hand preferably takes place in that at least one shift bevel is arranged directly on the shift carriage, by the axial displacement of which a torque introduction section of the torsion spring derived therefrom is displaced in the circumferential direction. In the case of a torsion spring whose two torque introduction sections are movable relative to the second bearing device in the circumferential direction, the shift carriage can also have two Schaltschrägen. Furthermore, a shift carriage with two shift bevels is advantageous if more than one torsion spring is used, so that each one torque introduction section of a plurality of torsion springs is jointly deflected by the shift carriage. If the shift carriage has a plurality of shift bevels, these are preferably offset from one another in the axial direction, so that there is no need to position the torque introduction sections of the plurality of torsion springs at the same height.

Instead of an immediate effect of the shift carriage on one or more torque introduction sections of the shift carriage can also act on a relative to the shift carriage intermediate member, which may be provided, for example, pivotally mounted on the second bearing means. This intermediate member in turn acts on one or more torque introduction portions of the torsion spring or torsion springs, so that they are deflected in response to the displacement of the intermediate member in the circumferential direction.

In order for the shift carriage or the intermediate member to displace it in the desired direction, in particular in a direction substantially extended in the circumferential direction, when the torque introduction section is subjected to force, it is advantageous if the torque introduction section movable relative to the second bearing device is movably guided. This can be achieved for example by a slot through which leads the torque introduction section. However, a guide is not absolutely necessary, since already the wrap-around shape of the spring usually ensures sufficient axial positional stability of the torque introduction sections.

It is also advantageous if a return spring is provided by means of which the shift carriage is permanently acted upon in the direction of its end position. It is particularly advantageous if this return spring is not formed as a separate spring element, but is formed by the one or more torsion springs. Thus, for example, with a suitable oblique position of said shift bevel while avoiding the range of self-locking can be achieved, that this serves the purpose in a described manner to convert the axial movement of the shift carriage in a circumferential direction of one or more torque introduction sections. At the same time, however, the torque introduction sections can also exert the restoring force on the shift carriage by exerting an axial force on the shift carriage by virtue of the torque introduction sections acting in the circumferential direction by deflecting the shift ramp.

Instead of a translationally displaceable switching carriage, a further design of the switching device provides a shift lever, which is pivotally mounted on the first or the second bearing device is attached and which is operatively coupled to the torsion spring such that a pivoting movement of the shift lever causes a tensioning or relaxing the torsion spring and thus blocking or releasing the blocking device, wherein preferably the shift lever is connected to a torque introduction portion of the torsion spring, so that these by a pivoting movement of the shift lever is displaceable in the circumferential direction.

If the blocking device has two torsion springs, a shift lever is preferably provided per torsion spring. The torsion or the torsion springs are preferably provided on the seat-side bearing means and each pivotable about a horizontal pivot axis. Preferably, an arm of the at least one shift lever is connected to a torque introduction portion of a torsion spring, so that it is moved in the circumferential direction when the shift lever pivots. The pivoting movement of the shift lever thus leads to the desired blocking or release.

As already mentioned, the switching of the blocking device can be realized in various ways.

A particularly advantageous design provides that it is a piece of seating furniture with a stand-up function, through which the seat can be raised to facilitate getting up from the sitting position. With such a piece of seating furniture, the blocking device can be operatively coupled with the stand-up assistance function in such a way that it assumes its blocked state upon actuation of the stand-up assistance function. The stand-up can be designed by a motor in a conventional manner. In principle, however, a mechanical, for example spring-operated stand-up assistance function is also conceivable. In the case of the coupling of the blocking device with the stand-up, it is particularly advantageous if a moving in the wake of the Aufstehhilfe moving fitting section forces or enables a shift of the shift carriage or the shift lever and thereby causes the blocked or released state of the blocking device.

The coupling of the stand-up assistance function with the blocking device is particularly useful because a rotation of the seat counteracts the easier getting up. The production of the blocked state upon activation of the stand-up is therefore expedient.

Another possible design for controlling the blocking device provides that for this purpose a control lever is provided for manual actuation, which is preferably also such that it is the axially displaceable shift carriage or the pivotable shift lever can move. Such a control lever may be provided in the manner well known by office seating pieces of furniture below the seat and allow either a permanent blocking and releasing or allow a temporary release from a normally blocked state by displacement of the operating lever.

The distribution of the first and second bearing device on the base or the seat is basically arbitrary. The blocking surface can therefore be either rotationally fixed to the seat or the base, while the torsion spring is stationary to the other storage device. Of advantage, however, is a design in which the blocking surface and the first bearing means are provided on the base side and the torsion spring and the second bearing means are provided on the seat side. This makes it possible to switch seat-side actuators such as the aforementioned operating lever or the stand-up assistance function in a facilitated manner with the torsion spring switching.

The invention relates not only to the piece of seating furniture as a whole but also a fitting for such a piece of seating furniture.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1a - 1c

ein erfindungsgemäßes Sitzmöbelstück in perspektivischer Ansicht, in Ansicht von hinten und in Ansicht von vorne,

Fig. 2

die Drehlagerung des Sitzmöbelstücks gemäß Fig. 1 mitsamt Blockiereinrichtung,

Fig. 3a bis 3c

die Blockiereinrichtung im freigegebenen Zustand,

Fig. 4a bis 4c

die Blockiereinrichtung im blockierten Zustand,

Fig. 5a und 5b

das Sitzmöbelstück der Figuren 1a bis 1c mit aktivierter Aufstehhilfe und

Fig. 6a bis 6b

eine alternative Form der Blockiereinrichtung.

Further aspects and advantages of the invention will become apparent from the claims and the following description of a preferred embodiment of the invention, which is explained with reference to the figures. Hereby show:

Fig. 1a - 1c

an inventive piece of seating furniture in perspective view, in view from behind and in front view,

Fig. 2

the pivot bearing of the piece of seating furniture according to Fig. 1 together with blocking device,

Fig. 3a to 3c

the blocking device in the released state,

Fig. 4a to 4c

the blocking device in the blocked state,

Fig. 5a and 5b

the piece of furniture of the FIGS. 1a to 1c with activated standing upright and

Fig. 6a to 6b

an alternative form of blocking device.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The FIGS. 1a to 1c show a seating piece of furniture according to the invention in the manner of a chair. This seat piece of furniture has a seat unit 10, in this case, in addition to a seat surface 12, which is not padded, also a backrest 14 and a leg rest 16. The seat unit 10 as a whole is rotatable relative to a base 20 about a vertical axis 2. The base 20 is intended for stationary installation of the piece of seating furniture, but could also be equipped in the manner of office chairs with rollers in order to be easily displaced as a whole.

The rotatability of the seat unit is achieved via a rotary bearing 30, which is arranged directly above the base 20.

Fig. 2 This rotary bearing is shown in a cut manner. In particular, it comprises an inner axle section 32, which is rotationally fixed to the seat unit 12, and a bearing sleeve 34 accommodating the axle section 32, which is an integral part of the base 20.

The asked by this pivot bearing with the components 32, 34 available rotation of the seat unit 10 relative to the base 20 is blockable in a piece of seating furniture according to the invention such that rotation can be prevented occasionally or at least significantly more difficult.

The main components of the blocking device provided for this purpose are described with reference to FIGS Figures 2 . 3 and 4 primarily a blocking surface 40, which is formed by the outer surface of the bearing sleeve 34 and two torsion springs 50a, 50b, which are each formed in the manner of leg springs. Both leg springs 50a, 50b are respectively fixed to the seat unit 12 with a leg 51a, 51b with respect to a circumferential direction about the rotation axis 2, while the respective opposite legs 52a, 52b are basically movable with respect to the circumferential direction. A circumferentially directed movement of the legs 52a, 52b leads to a tensioning or relaxing of the torsion springs 50a, 50b.

The torsion springs 50a, 50b surrounded with their respective 1.5 turns (corresponds to about 540 °) the blocking surface 40. The torsion springs 50a, 50b are tuned to the diameter of the blocking surface 40 that when eliminating an external moment acting on the legs, the springs assume a relaxed state in which they are pressed against the blocking surface 40. This represents the blocked state. So if not on the thighs 52a, 52b spreading moment present, the torsion springs 50a, 50b block a rotational movement of the seat unit 10 relative to the base 20th

In order to achieve the release, the displaceable legs 52a, 52b must be spread apart from each other. For this purpose, a switching slide 60 is available, which is displaceable in the axial direction illustrated by the arrow 4. The switching carriage 60 is for this purpose equipped with a slot 62 through which project two screws 63, which are screwed into the seat-side bearing device. The shift carriage 60 has two offset in the axial direction and oppositely inclined shift bevels 64a, 64b, against which the spring legs 52a, 52b. The switching bevels have an angle to the vertical of about 45 ° in the present case. Although, in principle, other angles are also conceivable here, it is advantageous if the angling of the shift bevels 64a, 64b is such that no self-locking occurs in both directions of action: it is desired that both a displacement of the shift carriage 60 be a spreading of the spring legs 52a, 52b, as well as that the legs 52a, 52b can initiate an axially acting force in the switching carriage 60 in order to reset this can.

The FIGS. 3a and 3b show the released state of the blocking device. This is given when the switching carriage 60 is in a lower end position, in which the legs 52a, 52b respectively in the region of the upper ends of the shift bevels 64a, 64b are arranged. They are thereby spread apart. The turns of the springs 50a, 50b are no longer clamped against the blocking surface 40. The lower end position of the shift carriage 60 is effected by a cross-beam 18 of the seat unit 10, which acts from above on the shift carriage 60 and this in the released position of FIGS. 3a and 3b do not dodge upwards.

Does this downward force application of the switching carriage 60, so the situation arises FIGS. 4a to 4c one. The shift carriage 60 is displaced upwards in the direction of the arrow 4a, since the legs 52a, 52b at the end of the torsion springs 50a, 50b are in their more relaxed position FIGS. 4a to 4c try to take. About the shift bevels 64a, 64b they press the shift carriage 60 upwards. In the state of FIGS. 4a to 4c Therefore, the turns of the torsion springs 50a, 50b are narrower and clamped against the blocking surface 40. A rotational movement of the seat unit 10 relative to the base 20 is no longer possible or only very difficult.

The FIGS. 5a and 5b clarify how the blocked state of FIGS. 4a to 4c is caused. The figures show the piece of seating furniture when the standing-up aid is activated. This stand-up aid allows a plurality of components of the seat unit 10 in the illustrated manner to pivot. These components include the said cross-beam 18, which consists of their in FIG. 5a Dashed line indicated starting position 18 'is raised, thereby losing the touch contact to the switching slide 60. As a result, this deviates upwards in the manner already described and establishes the blocked state of the blocking device. Activating the stand-up assistance function thus also automatically causes a blocking of the blocking device without a separate switching process.

The Fig. 6a and 6b show an alternative form of blocking device. In this case, instead of the carriage 60 with the shift bevels 64a, 64b, two shift levers 65a, 65b are provided, which are mounted pivotably about the axes 67a, 67b in relation to the seat unit side bearing device 32. At the respective lower end of these shift levers 65a, 65b, the spring legs 52a, 52b of the torsion springs 50a, 50b acting as torque introduction sections are fixed. The respective upper end of the shift lever is provided with a Einkopplungsabschnitt 66 a, 66 b, by the application of force, the shift lever 65 a, 65 b can be pivoted.

The actuation of the shift lever 65a, 65b is similar to the described switching slide 66 via the cross-beam 18. By lowering the cross-beam 18, the blocking device is released. If the cross-beam 18 is raised, then the torsion springs 50a, 50b can again assume their more relaxed state when the control levers 65a, 65b are pivoted, in which they abut the blocking surface 40 and thus put the blocking device in the locked state.

Claims (11)

1. Piece of seating furniture having

   - a base (20) and

   - a seat unit (10),

   wherein

   - the base and the seat unit have provided between them a pivot bearing (30) comprising a base-side bearing device (34) and a seat-unit-side bearing device (32), by means of which the seat unit (10) can be rotated about a vertical axis (2) in relation to the base (20), and

   - the pivot bearing has a switchable blocking device (40, 50a, 50b, 60), by means of which the rotary movement capability of the bearing devices (32, 34) in relation to one another can be blocked,

   characterized in that
   the blocking device (40, 50a, 50b, 60) comprises:

   - an encircling blocking surface (40) on a first of the two bearing devices (34),

   - at least one torsion spring (50a, 50b) which wraps around the blocking surface (40), which is fastened on the second bearing device (32) and has an internal diameter which is variable in dependence on the stressing state, and

   - a switching device (60), by means of which the torsion spring (50a, 50b) can be subjected to stressing and relieved of stressing,

   wherein the torsion spring (50a, 50b), in the stressed or relieved-of-stressing state, butts against the blocking surface (40) and thus prevents relative rotary movement between the bearing devices (32, 34).
2. Piece of seating furniture according to claim 1,
   characterized in that
   the torsion spring (50a, 50b) has two torque-inducing portions (51a, 51b, 52a, 52b), of which the circumferentially directed relative movement can subject the torsion spring (50a, 50b) to stressing and relieve the same of stressing.
3. Piece of seating furniture according to claim 2,
   characterized in that
   one of the torque-inducing portions (51a, 51b) is fastened on the second bearing device (32) such that it cannot be moved in the circumferential direction.
4. Piece of seating furniture according to any one of the preceding claims,
   characterized in that
   the torsion spring (50a, 50b) wraps, or the plurality of torsion springs (50a, 50b) together wrap, around the blocking surface (40) over an angle of at least approximately 360°, preferably over an angle of approximately 1080° or approximately 1800°, wherein in particular preferably two torsion springs (50a, 50b) are provided, each of these wrapping around the blocking surface (40) over an angle of approximately 540° or of approximately 900°.
5. Piece of seating furniture according to any one of the preceding claims,
   characterized in that
   the switching device (60) has a switching carriage (60), which can be moved axially with guidance along the first or the second bearing device (32) and which is operatively coupled to the torsion spring such that an axial displacement of the switching carriage (60) gives rise to the torsion spring (50a, 50b) being subjected to stressing or relieved of stressing and thus to the blocking device (40, 50a, 50b, 60) being blocked or released, wherein preferably

   - the switching carriage (60) has at least one switching slope (64a, 64b), it being possible for a torque-inducing portion (52a, 52b) of the torsion spring (50a, 50b), said portion sliding on said slope, to be displaced in the circumferential direction by the axial displacement of said slope, or

   - the switching carriage acts on an intermediate member which can be moved relative to the switching carriage and, for its part, acts on a torque-inducing portion of the torsion spring, so that this can be displaced in the circumferential direction.
6. Piece of seating furniture according to claim 5,
   characterized in that
   a restoring spring (50a, 50b) is provided, by means of which the switching carriage (60) is forced permanently in the direction of an end position, wherein the restoring spring (50a, 50b) is preferably identical to the torsion spring (50a, 50b).
7. Piece of seating furniture according to any one of claims 1 to 4,
   characterized in that
   the switching device has a switching lever (65a, 65b), which is fitted in a pivotable manner in relation to the first or the second bearing device (32) and which is operatively coupled to the torsion spring such that a pivoting movement of the switching lever (65a, 65b) gives rise to the torsion spring (50a, 50b) being subjected to stressing or relieved of stressing and thus to the blocking device (40, 50a, 50b, 60) being blocked or released, wherein preferably the switching lever (65a, 65b) is connected to a torque-inducing portion (52a, 52b) of the torsion spring (50a, 50b), so that the latter can be displaced in the circumferential direction by a pivoting movement of the switching lever (65a, 65b).
8. Piece of seating furniture according to any one of the preceding claims,
   characterized in that
   the piece of seating furniture has a standing-up-aiding function, by means of which the seat surface (12) can be raised, wherein the blocking device (40, 50a, 50b, 60) is operatively coupled preferably to the standing-up-aiding function such that it assumes its blocked state when the standing-up-aiding function is actuated.
9. Piece of seating furniture according to any one of the preceding claims,
   characterized in that
   the piece of seating furniture has an operating lever for manual actuation, which can be used to switch the blocking device, in particular by axial displacement of the switching carriage.
10. Piece of seating furniture according to any one of the preceding claims,
    characterized in that

    - the base-side bearing device (34) is formed by the first bearing device (34) with the encircling blocking surface (40), and

    - the seat-side bearing device (32) is formed by the second bearing device (32) with the at least one torsion spring (50a, 50b).
11. Fitting for a piece of seating furniture, having

    - a base portion for fitting on a base of the piece of seating furniture and

    - a seat portion, on which to fit a seat unit of the piece of seating furniture,

    wherein

    - the base portion and the seat portion have provided between them a pivot bearing (30) comprising a base-side bearing device (34) and a seat-unit-side bearing device (32), by means of which the seat portion can be rotated about a vertical axis (2) in relation to the base portion, and

    - the pivot bearing (30) has a switchable blocking device (40, 50a, 50b, 60), by means of which the rotary movement capability of the bearing devices (32, 34) in relation to one another can be blocked,

    characterized in that
    the blocking device (40, 50a, 50b, 60) comprises:

    - an encircling blocking surface (40) on a first of the two bearing devices (32, 34),

    - at least one torsion spring (50a, 50b) which wraps around the blocking surface (40), is fastened on the second bearing device (32) and has an internal diameter which is variable in dependence on the stressing state, and

    - a switching device (60), by means of which the torsion spring (50a, 50b) can be subjected to stressing and relieved of stressing,

    wherein the torsion spring (50a, 50b), in the stressed or relieved-of-stressing state, butts against the blocking surface (40) and thus prevents relative rotary movement between the bearing devices (32, 34).

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