AN OFFICE-TYPE CHAIR AND AN ASSOCIATED ADJUSTING DEVICE

D E S C R I P T I O N

Technical field of the invention

The object of the present application refers to a mechanism for actuating an adjusting device of office-type chairs.

Particularly, the present application refers to an office chair provided with movable parts such as the seat, back, armrests adjustable by suitable adjusting devices.

Moreover, an object of the present application is an adjusting device for office-type chairs and a chair comprising at least one such device.

Prior art

As it is well known, a chair, and particularly an office chair, in order to be ergonomic and satisfy regulatory requirements must be provided with two or more adjusting devices enabling to modify the tilt of the movable parts in order to be adapted to the contour of each user.

In order to find a wide and advantageous use, the adjusting device must be easy and prompt to be used, with smooth and simple operations. Moreover, the adjusting device must ensure a determined safety.

The adjusting device, which is made reference to, is, particularly but not limitatively, the one described in the European patent No. EP 2 255 697 B l obtained by the same Applicant.

Such locking/unlocking device substantially comprises a box structure having a support coupled to the moveable parts of the chair and articulated to an axially movable pin. The pin projects laterally from the box structure and is moved by a rotating knob graspable by the user.

Clockwise or counterclockwise rotating the knob actuates the axially movable pin for enabling to adjust the support and enabling to stop the seat and/or back tilt according to desired positions. The knob is located in proximity with the box structure and axially with the adjusting pin.

For obtaining the desired rotation of the knob, the user is compelled to stretch himself/herself under the seat by taking uncomfortable and awkward positions.

Even though such solution is satisfying under different aspects, it has for some users a non-optimal operation. An alternative solution provides to actuate the adjusting device by a spring pushbutton associated to a mechanism provided with a cylinder having suitable alternate lock side slots, which is axially coupled to the pin.

By actuating the spring pushbutton the cylinder axially moves the pin in order to enable to stop the seat and/or back according to the desired positions.

Such solution is not completely satisfying from the point of view of the convenience of application.

In order to obviate such drawbacks, a known solution provides to interpose a wire connection between the adjusting pin and the spring pushbutton in order to position the pushbutton in a more comfortable position for the user.

Also such solution, even though is satisfying under different aspects, does not have the structural and operative simplicity which the invention of the present application addresses to.

The technical problem underlying the present application consists of devising an actuating mechanism for an adjusting device for office-type chairs, having structural and operative features such to meet the requested requirements, overcoming the disadvantages cited with reference to the prior art.

Brief summary of the invention

The idea of solution underlying the present invention consists of providing a couple to articulated elements cooperating one to each other to activate the adjusting pin without impairing the actuating features and having operative efficiency and a structural simplicity.

Based on such idea of solution, the technical problem is solved by a mechanism for actuating as defined in claim 1 and in the preferred embodiments thereof described in the dependent claims.

It is also an object of the invention an adjusting device as defined by claim 13 and an office-type chair described by claim 14.

Brief description of the drawings

Further characteristics and advantages of the invention will be understood by the following description of a preferred embodiment and of variants thereof exemplifyingly given with reference to the attached drawings, wherein:

Figures 1 and 2 schematically show with perspective views, portions of an office- type chair having two adjusting devices both provided with an actuating mechanism implemented according to the present invention; Figure 3 is an exploded view of the portion of the chair in Figure 2 rotated by 90°;

Figures 4 and 5 respectively show, in a three-quarter perspective view and an exploded view, a portion of the actuating mechanism according to the present invention;

Figures 6, 7 and 8 show the portion of the mechanism in Figure 4 in a side view, a plan view and a cross-section view according to line I-I of Figure 7;

Figures 9 and 10 show, with two different three-quarter perspective views, a detail of the actuating mechanism;

Figures 11a, l ib, and 11c respectively show with a front view, a cross-section view according to line II-II, and with a side view, a detail of the adjusting block;

Figures 12a and 12b show with a side view and a cross-section view according to line III-III, a further portion of the actuating mechanism according to the present invention, in an unlocking position;

Figures 13a and 13b show a side view and a cross-section view along line IV-IV of the portion of the actuating mechanism in an unlocking position;

Figures 14a and 14b, 15a and 15b show further side views and cross-section views along line V-V and line VI- VI, of the portion of the actuating mechanism in a locking position;

Figure 16 is an enlarged three-quarter upside-down view of a portion of the actuating mechanism shown in Figure 2;

Figures 17, 18 and 19 show enlarged portions of the actuating mechanism in Figure

16.

Detailed description

An office-type chair 1 is schematically shown in the attached figures. The chair 1, in the illustrated embodiment, comprises a substantially box structure 100 which is associable to a seat and/or a back and is suitable to adjust their tilt.

The box structure 100 comprises an upper half- shell 102 and a supporting element 104 articulated by a pin 105 to a lower half-shell 101. The seat 103 is fixed to the upper half- shell 102 by interposed transversal brackets 106. The supporting element 104 has a portion projecting from the upper half-shell 102 which is coupled to a perpendicularly positioned back 108 by the interposition of a back blade.

An adjusting device 2 enables to lock the upper half-shell 102 and therefore the seat 103 with respect to the lower half-shell 101, in order to adjust the tilt of the seat 103. A further adjusting device 2 enables to lock the supporting element 104 to the lower half-shell 101 enabling in this way to adjust the tilt of the back 108.

Each adjusting device 2 comprises a locking assembly 4 axially inserted in a respective sleeve 9. The sleeve 9 has a prevalent longitudinal extension along a first direction X-X and is outwardly and perpendicularly coupled to the side surface of the lower half- shell 101.

The locking assembly 4 comprises a locking pin 5 axially extending along a first direction X-X and moves axially and in parallel in the first direction X-X, countering a first and second return springs 6 and 7. The first and second springs 6 and 7 are coaxially located with respect to the locking pin 5.

The locking pin 5 has a free end 5a projecting from the sleeve 9 and suitable for being engaged with dedicated interconnecting holes formed in the side surface of the lower half-shell 101 and at the side surface of the upper half-shell 102 and/or of the supporting element 104, for locking and unlocking the same with respect to the axial movement of the adjusting pin 5, from a locking position to an unlocking position.

The locking pin 5 has a terminal end 5b, opposite to the free end 5a.

The first spring 6 is inserted from the free end 5a and abuts against an edge 5c annular with respect to the locking pin 5. The second spring 7 is inserted from the terminal end 5b, coaxially with the locking pin 5 and abuts against the edge 5c on the opposite portion with respect to the first spring 6. Further, a cylindrical bush 8 comprises a centrally hollow gripping surface 8a which is perimetrally provided with a plurality of wings 8b. The bush 8 is coaxially inserted with respect to the locking pin 5, the second spring 7 being pressure inserted among the wings 8b.

The locking pin 5 of the adjusting device 2 is suitable for being driven by an actuating mechanism 3, according to the present invention.

The actuating mechanism 3 comprises a motion transmission 10 to convert a rotation motion to a translational motion coupled to the locking assembly 4. The motion transmission 10 is suitable for actuating the axial movement of the locking pin 5, from the locking position to the unlocking position and viceversa, by means of the rotation of a switching lever 20. The switching lever 20 is rotatably coupled to a supporting block 30 and is coupled to the motion transmission 10 by the interposition of connecting means 40. The switching lever 20 is selectively positioned in a first stopping position and a second stopping position. According to one embodiment, the switching lever 20 is activated by a user. Particularly, with reference to the selective position performed by the switching lever 20, the locking pin 5 is translated by the motion transmission 10 actuated by said connecting means 40.

The supporting block 30 is associable to the seat 103 of the chair 1 in a predetermined position comfortable to an user, for example downwardly associated in proximity of the peripheral portion.

According to an embodiment, the motion transmission 10 comprises a thrust member 15 that is rotatably coupled to the side surface of the sleeve 9 by a pin 19 and is suitable for cooperating with the locking assembly 4. The pin 19, coupled to the sleeve 9, is located with an axis Z-Z substantially normal to the first direction X-X and the axis of the locking pin 5.

According to an embodiment illustrated in Figures 9 and 10, the thrust member 15 is provided with a thrust wall 16, substantially a plate that is perpendicularly coupled to a hooking portion or wall 17 in order to define an L- shaped hooking element. A hooking edge of the element is adapted to comprise a hole for housing of the rotating pin 19.

During the operation, the thrust wall 16 is located in proximity of the bush 8 and terminal end 5b of the locking pin 5. The connecting means 40 are coupled to the hooking wall 17 and are suitable for putting in rotation the thrust member 15 on said rotating pin 19 from a release position to a thrust position.

In the release position, illustrated in Figure 15b, the thrust wall 16 is arranged facing the bush 8, while in the thrust position, illustrated in Figure 12b, the thrust wall 16 is rotated about the pin 19 until it takes a position substantially normal to the gripping surface 8a of the bush 8.

The connecting means 40 comprises a cable 41 having a first end 42 removably coupled to the switching lever 20 and a second end 43 coupled to the hooking wall 17 of the thrust member 15.

The connecting means 40 can further comprise first and second coupling means, 60 and 65, respectively suitable for coupling the first end 42 of cable 41 to the supporting block 30 and the second end 43 of sleeve 9, in an optimal position in proximity of the motion transmission 10 and switching lever 20.

Preferably, the cable 41 is slidingly inserted in an outer protection sheath 41a comprising, in an embodiment, said first and second coupling means, 60 and 65.

The locking support 30 is a substantially parallelepiped hollow body provided with an abutment base 31 prevalently developing along a second direction A-A. Opposing longitudinal side walls 32a and 32b extend from base 31 and between opposite end profiles 32c and 32d.

The switching lever 20 has a transversal hole 22 extending in a third direction Y-Y which, when the switching lever 20 is associated to the supporting block 30, is substantially normal to the second direction A-A. The hole 22 is suitable for housing a rotating pin 21.

The ends of the rotating pin 21 project from the hole 22 and are received in respective seats 24a, 24b formed in said opposing side walls 32a and 32b. The seats 24a and 24b are positioned in proximity of the end profile 32c in order to keep the switching lever 20 with a first portion 20a projecting from the end profile 32c.

In a preferred and non-limiting way, the switching lever 20 is integrally formed with the first portion 20a, substantially a small plate adapted to be gripped and moved by the user. The first portion 20a is coupled to a second portion 20b formed by a substantially parallelepiped body positioned between said opposing side walls 32a, 32b.

Coupling or stopping means 25 are interposed between the supporting block 30 and the switching lever 20 and are suitable for interrupting the rotation of the switching lever 20 at least in a stopping position.

The stopping means 25 comprise a resiliency deformable element 26, 27a, 27b suitable for cooperating with at least one locking element 33a, 33b, 34a, 34b.

In an embodiment, the stopping means 25 comprise a spring 26 and a pair of balls 27a, 27b. The spring 26 is preloaded and housed with the pair of balls 27a, 27b in a housing 23, substantially a second transversal hole 23 extending along a direction Y'- Y' substantially parallel to the third direction Y-Y of the hole 22 adapted to house the rotating pin 21.

A first locking element is defined by a first pair of notches 33 a, 33b and a second locking element is defined by a second pair of notches 34a, 34b made in the opposing side walls 32a, 32b of the supporting block 30.

In this way, the switching lever 20, when is actuated by the user, rotates about the rotating pin 21, alternatively housing the pair of balls 27a and 27b in the first pair of notches 33a, 33b or in the second pair of notches 34a, 34b, in order to define a stopping position and an unlocking position or a first and a second stopping position.

In an embodiment, the second portion 20b of the switching lever 20 is shaped in order to have a first hook 28 which, during the operation, projects below the parallelepiped body in the opposite side with respect to the second hole 23. The first hook 28 comprises a fork element 29 coupled to the parallelepiped body and spaced from the latter in order to define a seat 28a housing a first stop 45, substantially shaped as a ball, and coupled to the first end 42 of cable 41.

The fork element 29 has a first slot 29a extending in a direction which, during the operation, is substantially parallel to the second direction A-A.

The first slot 29a enables to insert the first stop 45. The first locking means 60 comprise a first annular notch 61 formed in the protection sheath 41a and suitable for being pressure inserted in a first opening 35 formed in the supporting block 30 below the end profile 32d.

The first coupling means 60 cooperate with the first stop 45 in order to enable a stable connection between the cable 41 and supporting block 30.

The second end 43 of cable 41 comprises a second stop 46 inserted in second slot 18a formed in the hooking wall 17 of the thrust member 15, as illustrated in Figures 16 and 17.

The second stop 46 is housed in a dedicated seat 18b, the cable 41 exiting the second slot 18a.

The second coupling means 65 comprise a second annular notch 66 formed in the protection sheath 41a and suitable for being pressure inserted in a second opening 67 provided at the side wall of sleeve 9.

The second coupling means 65 cooperate with the second stop 46 in order to enable a stable connection between the cable 41 and sleeve 9.

In an embodiment, a closing element or plug 48 is coupled to the free end of sleeve

9.

With reference to the operation, when the switching lever 20 is in the unlocking position, the thrust member 15 is in the release position, illustrated in Figure 15b, the thrust wall 16 facing the gripping surface 8a of the bush 8. Next, when the switching lever 20 is in the stopping position, the substantially tensioned cable 41, coupled to the hooking wall 17, moves the thrust member 15 until it reaches the thrust position. The thrust wall 16, rotating about the pin 19, thrusts the bush 8 which translates the edge 5c enabling to axially move the locking pin 5, from the unlocking position to the locking position, and to simultaneously compress the first and second springs 6 and 7 which are in this way loaded.

Next, the user, by actuating the switching lever 20, moves it to the unlocking position, so the cable 41 is loosened and the first and second springs 6 and 7 are unloaded. In this way the thrust member 15 returns to the release position and the locking pin 5 in the unlocking position, as illustrated in Figure 15b.

In this way, the user by raising or lowering the switching lever 20, enables to actuate the adjusting device 3 by moving the locking pin 5 axially.

A suitable design of the involved forces, enables to adjust the elasticity of the first and second springs 6 and 7 with respect also to the possible elasticity of the cable 41 and to suitably define the size of the components.

The configuration of the actuating mechanism, according to the present invention, enables to fix the supporting block and therefore the switching lever in any point of the chair, making easy the operation by the user. This fact enables also to position the switching lever substantially independently from the configuration of the chair itself.

The present invention also refers to an adjusting device comprising an actuating mechanism according to what has been previously illustrated and described.

Further, the present invention refers to an office-type chair comprising one or more adjusting devices singularly provided with a respective actuating mechanism according to what has been described and illustrated.

Obviously, the present invention is susceptible to several variants. For example, the motion transmission converting the rotary motion to a translational one can be implemented by different elements, such as a pin coupled to a worn, a pair of gear wheels and similar. Further, also the stopping means between the supporting block and the switching lever can have different and analogous embodiments with respect to the one described, all falling into the scope as defined in the following claims.