EP4698013A1 - Tablet for supporting one or more objects and chair structure including the tablet - Google Patents

Abstract

A tablet for supporting one or more objects having a shelf (2) suited to allow the positioning of one or more objects; an articulation (4) anchored to the shelf (2) and suited to rotate around a predetermined first axis of rotation (R₁) to allow the selective rotation of said shelf (2); a support element (6) having ends (7, 8) connected, respectively, to the articulation (4) and to the chair or armchair structure; constraint means (21) suited to promote selective locking/unlocking of the shelf (2) in the operating position, such constraint means (21) comprising a pin (22) operatively connected to the support element (6) and a shaped seat (25) formed in the articulation (4) to allow the insertion of the pin (22). The shaped seat (25) comprises a first portion (28) suited to allow the insertion of the pin (22) with reduced clearance to define a rotational constraint for the articulation (4) around the axis of rotation (R₁) and lock the shelf (4) in the operating position, and a second portion (29) suited to allow the insertion of the pin (22) and suited to rotate selectively around the first axis of rotation (R₁) and the pin (22) during the rotation of the articulation (4) to allow the partial or full insertion of the pin (22) into the second portion (29). The tablet also includes actuating means (31) suited to promote the controlled movement of the articulation (4) and/or the pin (22) with respect to the support element (6) to promote the selective insertion of the pin (22) in the first portion (28) or the second portion (29). A chair structure comprising the tablet.

Description

TABLET FOR SUPPORTING ONE OR MORE OBJECTS AND CHAIR STRUCTURE INCLUDING THE TABLET

DESCRIPTION

Scope of the invention

[001] The present invention is located in the technical field of furniture and furnishings and is particularly concerned with a tablet for supporting one or more objects. Also provided is a chair structure intended to supplement the present tablet for supporting one or more objects.

State of the art

[002] As is well known, many chairs or armchairs allow for the integration of a tablet equipped with a support surface on which the user can place different types of material during the time the user maintains a sitting position.

[003] This type of chair is particularly popular in all those environments where people need to perform certain activities while sitting.

[004] For example, the tablet allows the user to support notebooks, pens, laptops or smartphones so that the user can take notes or perform various tasks during a work session, conference or other similar events for which the user is expected to sit in the chair for long intervals of time.

[005] It is not surprising, therefore, that chairs or armchairs equipped with a tablet are often used in offices, universities, convention centers and all places where people gather and who must also perform activities while the seated.

[006] In the field of chairs and armchairs, therefore, there is a need to make a structure that provides the tablet with some special features.

[007] First, the overall ergonomics of this type of chair must be quite high in order to ensure a particularly comfortable position of the user, both when he or she performs activities with the help of the tablet (e.g., writing or using an electronic device) and when he or she remains the seated without performing any further actions (in fact, without involving the use of the tablet).

[008] In addition, it has long been known how the encumbrance of a tablet that remains in the working position (i.e., arranged substantially along a horizontal plane) greatly increases the overall encumbrance of the chair or armchair.

[009] For this reason, an additional peculiarity of this type of chairs and armchairs is to drastically reduce the size when the tablet is not in use by the user; thus, space can be managed in an optimized manner and more chairs can be placed even when the tablet is not required.

[0010] In addition to the above, the types of chairs that incorporate the installation of a seat must provide a system for moving the seat that is safe, reliable, and particularly easy to operate by a user.

[0011] In fact, it should be pointed out how the tablet should move from a folded position (where it remains unused) to an active position (i.e., set up to support one or more objects) quickly and without particular effort on the part of the user.

[0012] In addition, the tablet must be able to support a relatively heavy weight without running into sudden failure or movement that would result in objects resting on the supporting surface falling off (with a consequent danger to the user as well).

[0013] In an attempt to solve the above problems, some special chair or armchair configurations designed to integrate a tablet have been developed.

[0014] Patent document EP 0 995 376 describes a foldable chair structure including a tablet, which is also foldable. The tablet is connected to the chair structure by an articulation formed by a number of mutually coupled parts that are selectively movable between a lower position (in which the tablet maintains a substantially vertical position), and an upper position (in which the tablet assumes a horizontal configuration). In addition, the articulation has a tilt and rotation mechanism consisting of a horizontal the articulation and a vertical the articulation. The horizontal the articulation consists of an additional sleeve provided with a stop cam, and a tubular element having a recess arranged eccentrically below the tablet. The vertical the articulation, on the other hand, consists of a tubular the seat and a pin suitable for insertion into that the seat; this pin can be pushed into the tubular the seat so as to compress a spring and disengage stops associated with the tablet. In this way, therefore, the user can promote selective (and safe) rotation of the tablet from the upper to the lower position.

[0015] The tablet handling mechanism described in the above chair structure is rather complex and requires anchoring the articulation directly to the armrest of the chair itself; moreover, this mechanism has some stringent limitations in the positions that the tablet can assume in relation to the user.

[0016] Patent document US2002/0190546 describes a chair comprising a seat, a backrest and a tablet that can be moved between a lowered (nonoperational) and a raised (operational) position. When the shelf is in a lowered position, the shelf is kept inclined with respect to a plane of symmetry of the chair, so that two or more chairs of the same type can be placed side by side longitudinally with each other, with the boards of adjacent chairs in a partially overlap the ping position. Again, an articulating element comprising two coupled and mutually rotatable bodies is provided. One of the bodies has a groove of semicircular shape that has an extension of 180°, within this groove a pin can slide, and the stop of the latter with the ends of the groove defines the limiting positions that the tablet can assume in rotation. There is also a spring-loaded retaining mechanism designed to hold the tablet in a stable position when it is in the lowered position. Specifically, this mechanism comprises a pair of the pins mounted slidingly within appropriate slots formed on one of the bodies; the ends of these the pins engage removably on recesses formed on the other body of the articulation.

[0017] The articulation described in the above paper is rather elaborate in construction and does not allow the tablet to be folded into a position that minimizes the chair's footprint when the chair is not in use, such as by placing it posterior to the backrest. Moreover, even in this case the positioning of the tablet relative to the user is severely restricted.

[0018] In addition, the chair structures commented on in the previous papers do not provide for a tablet suitable for fully symmetrical use whether the user is right-handed or left-handed.

[0019] In other words, the tablet handling mechanism described in the cited documents does not provide the tablet with the same degrees of freedom in handling (and thus the ability to assume the same end positions) when it is placed to the right of the chair frame (right-handed user) or to the left of the chair frame (left-handed user).

[0020] Patent document US 6,422,646 describes a stand intended to cooperate with a chair frame. The stand is specifically designed to support a computer keyboard in an optimal operating position for the user. The stand has a clamp attached to the stem of a pedestal chair, an arm extending transversely and laterally from this clamp, a first vertical tubular member and a second vertical tubular member mutually the pined to each other, and a substantially transverse tablet. The first and second tubular elements define two axes of rotation offset transversely from each other, around which the tablet can rotate. Thus, the user can adjust the position of the tablet to the right or left of the chair structure through the rotations impressed around, respectively, the vertical axis defined by the clamp and the vertical axes defined by the first and second tubular elements.

[0021] However, the solution proposed by this chair structure has the drawback of not allowing the tablet to be folded into an idle position.

[0022] In this, way therefore, it is not possible to reduce the overall footprint of the structure when the user does not intend to make use of the tablet during the amount of time he or she remains the seated.

[0023] In addition, the articulation allows the tablet to make rotations in a limited range, at the expense of the tablet's flexibility of use.

[0024] As a result, the ergonomics of the chair achieved through the structures described above are limited as is the comfort perceived by the user while using the tablet.

Document KR 101 980 441 describes a tablet suitable for integration into a chair or armchair structure to allow objects to be supported. However, the tablet described in that document also manifests the same drawbacks mentioned above.

Presentation of the invention

[0025] The present invention aims to overcome the above technical drawbacks by providing a particularly efficient and high-performance tablet for supporting one or more objects.

[0026] Specifically, one purpose of the present invention is to provide a tablet for the support of one or more objects whose use is found to be particularly ergonomic by any type of user, whether right- or left-handed.

[0027] A further purpose of the present invention is to provide a tablet for the support of one or more objects that exhibits a high degree of freedom of movement regardless of the side of use it assumes with respect to the user.

[0028] Another purpose of the present invention is to provide a tablet for supporting one or more objects that is simple to make and easy to assemble.

[0029] A further purpose of the present invention is to provide a tablet for supporting one or more objects that is particularly safe during use and is capable of maintaining a stable active position even when the user interacts with it unintentionally.

[0030] A further purpose of the present invention is to provide a tablet for supporting one or more objects that allows easy switching from the active position to the inactive position (and vice versa), without requiring high efforts on the part of the user.

[0031] Another purpose of the present invention is to make available tablets for supporting one or more objects that is capable of fitting most types of chairs and/or armchairs currently on the market.

[0032] Again, one purpose of the present invention is to make available a tablet for supporting one or more objects that can be easily installed as an additional accessory in a previously made chair and/or armchair structure to adapt the latter to the particular needs that have arisen subsequent to its manufacture/marketing.

[0033] Not the least purpose of the present invention is to make available a tablet for supporting one or more objects that, when it defines an add-on accessory for a chair structure, presents a minimal footprint so as to optimize packaging and reduce transportation cost.

[0034] These purposes, along with others that will be better elucidated below, are achieved by a tablet for supporting one or more objects of the type in accordance with claim 1.

[0035] Other purposes that will be better described below are achieved by a tablet for supporting one or more objects in accordance with dependent claims.

[0036] The above purposes, moreover, are also achieved by a chair structure of the type in accordance with claim 15. Brief description of the drawings

[0037] The advantages and features of the present invention will clearly emerge from the following detailed description of some preferred but not limiting configurations of support tablet for one or more objects with special reference to the following designs:

- Figure 1 includes a perspective view from below of a tablet subject of the present finding according to an initial configuration;

- Figure 2 is a top view of the tablet in Figure 1 ;

- Figure 3 is a perspective view of an early detail of the tablet in Figure 1 ;

- Figure 4 is a schematic view from above of the shaped seat visible in Figure 3;

- Figure 5 is a schematic top view of a second detail from Figure 1 ;

- Figure 6 is a sectional view of the detail in Figure 4 during a rotation sequence;

- Figure 7 is a cross-sectional side view of the tablet in Figure 1 ;

- Figure 7 bis is a sectional view of a tablet that is the subject of the present finding in a further realization configuration;

- Figure 8 is a perspective view of a detail of Figure 1 in an early implementation version;

- Figure 9 is a perspective view of the same detail in Figure 8 in a second realization version;

- Figure 10 is a cross-sectional side view of a tablet that is the subject of the present finding in a second realization configuration;

- Figure 11 is a cross-sectional side view of a tablet that is the subject of the present finding in a third realization configuration;

- Figure 12 is a cross-sectional side view of a tablet that is the subject of the present finding in a fourth realization configuration;

- Figures 13 through 16 are schematic depictions of a plurality of configurations of connecting the tablet that is the subject of the present finding to a chair structure.

Detailed description of the invention

[0038] The present invention relates to a support tablet for one or more objects, globally referred to in the Figures by the reference number 1.

[0039] Tablet 1 referred to the invention described here is of the type that can be anchored to a chair or armchair structure so as to provide an aid for the user who, while sitting, needs support for objects of various types or intends to perform some specific activity.

[0040] Specifically, this tablet 1 enables support for tools used for writing or reading such as, for example, books, notebooks, pens or electronic devices that perform the same functions such as laptops, smartphones, tablets, e-readers/writers, etc.

[0041] More generally, the purpose of this tablet 1 is to provide support for a multitude of objects provided to a user who remains the seated in the chair/armchair. These objects may vary in size and weight from a few grams to a few kilograms.

[0042] In addition, the present tablet 1 can be arranged to integrate from the outset into a chair/armchair structure, that is, it is possible to consider the chair/armchair as a finished product comprising, at the time of its manufacture, both a structure (i.e. , a frame, the sitting area, upholstery, etc.) and a tablet of the type described here anchored to that structure.

[0043] It is possible, however, to consider the tablet 1 object of the present as a standalone object; in this case the tablet 1 can be considered an accessory independent of the chair structure that is anchored to the latter upon request.

[0044] In this way, the tablet 1 represents an individually producible and marketable object that can be used to complete a chair/armchair structure even after the latter has been sold and installed.

[0045] In addition, the tablet in accordance with the present invention may be applied to a chair or armchair structure having a sitting area substantially symmetrical with respect to a plane passing through its centerline. Such a plane is indicated in Figures from 13 to 16 by the letter M.

[0046] A first embodiment of tablet making will be described below, which can be seen in Figures 1 through 9.

[0047] Conveniently, the tablet includes a shelf 2 suitable for placing one or more objects.

[0048] As mentioned earlier, the shelf 2 can be arranged to support various objects, e.g., books, notebooks, writing materials, electronic devices, etc.

[0049] In general, the shelf 2 may have the appearance of a parallelepiped with a predetermined plan form.

[0050] In this way, the shelf 2 may have an upper surface 3 that has a relatively large area for supporting one or more objects and a relatively small thickness Si so as not to interfere with the user's body parts during use.

[0051] In the version of the tablet shown in the Figures, the shelf 2 has a substantially square plan form, although other shelf geometries are possible (e.g. circular

[0052] The centerline plane can be seen in Figure 2 and has been indicated with the reference TT-TT.

[0053] Conveniently, the tablet 1 comprises an articulation 4 intended to be associated with the shelf 2. [0054] Specifically, the articulation 4 may be anchored to the shelf 2 at the lower surface

5 of the latter.

[0055] For this purpose, it is possible to promote the connection of the articulation 4 to the lower surface 5 of the shelf near a vertex of the square that defines the plan form of the shelf 2.

[0056] In addition, the tablet 1 involves the use of a support element 6 having a predetermined shape and ends 7, 8 respectively connected to the articulation 4 and the chair/armchair structure intended to comprise the tablet 1.

[0057] In a particular form of embodiment of the invention, the end 8 of the support element 6 (intended to be anchored to the chair/armchair structure equipped with a gas cylinder) may consist of a piece of tube intended to engage a substantially cylindrical, rotatable, slightly conical element (not shown in the Figures). This cylindrical/swivel/conical element may in turn be configured to be inserted into the end of the gas cylinder of the chair structure, this cylinder, moreover, generally slides within a chamber formed on the central support of the structure suitable for supporting the sitting area.

[0058] As best seen in Figure 7, the articulation 4 is arranged to be connected to both the shelf 2 and support element 6 (at end 7 of the latter).

[0059] In the case of the tablet 1 configuration visible in the Figures, the support element

6 is tubular and the articulation 4 provides a sleeve 9 suitable for insertion on an end portion 7 of that tubular support element 6.

[0060] In addition, the articulation 4 comprises an enlarged central portion 10, generally with a substantially circular plan form, connected to the sleeve 9 and having an upper face 11 intended to contact the lower surface 5 of the shelf 2.

[0061] There is, in addition, an elongated pin 12 suited to bind the central portion 10 of the articulation 4 to the shelf 2; in particular, this elongated pin 12 has an end 13 interacting with the central portion 10 of the articulation 4 and an opposite end 14 interacting with the shelf 2.

[0062] Conveniently, the articulation 4 may be mounted at the end 7 of the support element 6 so as to present a degree of freedom in rotation around a predetermined first axis of rotation Ri.

[0063] In particular, the first axis of rotation Ri is basically co-axial with sleeve 9 inserted on the end of the support element 6.

[0064] During rotation about the first axis Ri, the support element 6 remains fixed, while the articulation 4 rotates relative to it. Consequently, the sleeve 9 and the central portion 10 of the articulation 4 also rotate simultaneously with respect to support element 6.

[0065] When the articulation 4 rotates around the first axis of rotation Ri, the shelf 2 is also pulled into rotation by its connection to the articulation 4, so as to promote the rotation of the shelf 2 itself between an inoperative position, in which objects of various kinds cannot be placed on the same, and an operative position, in which the user can place objects on the upper surface 3 of that the shelf 2.

[0066] In general, the articulation 4 can rotate around the first axis of rotation Ri with an angular range i of not less than 90°.

[0067] In the inoperative position, the shelf 2 has a minimal footprint and is spaced from the sitting area of the chair/armchair structure (normally arranged to the side of the sitting area).

[0068] In this position, access to the sitting area by a user is unobstructed, and the user can sit and stand up from the chair/armchair without interfering with the shelf 2.

[0069] In the operative position, the shelf 2 is arranged above the sitting area so that it is placed in front of the torso of the user who is sitting on the chair/armchair.

[0070] In this position, the user will be able to place objects on the upper surface 3 of the shelf 2, while the articulation 4 (anchored to the shelf 2 at the lower surface 5) faces downward, that is, toward the user's legs.

[0071] Considering a chair/armchair resting on the ground, in the inoperative position, the shelf 2 may be substantially orthogonal to the ground (i.e., the shelf assumes a substantially vertical position), while in the operative position, the shelf 2 may be substantially parallel to the ground (i.e., assume a substantially horizontal position).

[0072] As a result, the operative and inoperative positions are angularly spaced about 90° apart.

[0073] As best seen in Figure 2, the shelf 2 is anchored to the articulation 4 in such a way as to keep the first axis of rotation Ri lying on the TT-TT centerline plane; in other words, the TT-TT centerline plane is oriented in such a way as to contain all points defining the first axis of rotation Ri.

[0074] In this way, the shelf 2 is symmetrical with respect to both the TT-TT centerline plane and the first axis of rotation Ri.

[0075] Appropriately, the shelf 2 may rotate between an operative and an inoperative position as a result of a user-promoted action on the elements of tablet 1.

[0076] Appropriately, the elongated the pin 12 connecting the articulation 4 to the shelf 2 can be considered a rotational the pin for the shelf 2 itself. In this way, such shelf 2 can rotate relative to the articulation 4 around a second axis of rotation R2 passing through the elongated the pin 12.

[0077] The second axis of rotation R2 is essentially orthogonal to the first axis of rotation Ri.

[0078] For example, the first axis of rotation Ri may be essentially horizontal (i.e., parallel to the ground) while, when the shelf is in the operative position, the second axis of rotation R2 may be essentially vertical.

[0079] The shelf 2 may rotate around the second axis of rotation R2 with a predetermined angular excursion A2.

[0080] For example, as best seen in Figure 5, the angular excursion A2 of the shelf 2 around the second axis of rotation R2 may be between 120° and 300°.

[0081] The angular excursion A2 of the shelf 2 around the second axis of rotation R2 can be essentially symmetrical with respect to the first axis of rotation R1.

[0082] Taking, in fact, the first axis of rotation R1 as a reference, the angular excursion A2 of the shelf 2 around the second axis R2 can be obtained as the sum of two angles a, a', which are formed with respect to the first axis of rotation R1, A = |a| + |a'|.

[0083] The angles a, a' have essentially equal modulus with each other but ends positioned on opposite sides of the first axis of rotation R1 (it is, therefore, possible to define a rotation of the shelf 2 that, with respect to the image in Figure 5, can extend between two ends placed to the right and left of the first axis of rotation R1, respectivelyi). [0084] Conveniently, the support element 6 that supports the shelf 2 and the articulation 4 can be anchored to the chair/armchair structure in a rotatable manner.

[0085] Specifically, support element 6 may be anchored to the chair/armchair structure near the central stem that supports the seat, or at another structural element of the chair/armchair (such as a support leg).

[0086] One end 8 of the support element 6 is anchored to the chair/armchair structure in such a way as to define a constraint with it with respect to upward or downward translation; however, this end 8 is rotatably connected with respect to the chair/armchair structure so as to allow rotation of the support element 6 around a third axis of rotation R₃.

[0087] The third axis of rotation R₃ is through the end 8 of the support element 6 anchored to the chair/armchair structure and is essentially parallel to the second axis of rotation R2, when the shelf 2 is in the operating position.

[0088] In general, the third axis of rotation R₃ may be substantially vertical.

[0089] In addition, the support element 6 will be able to rotate with respect to the third axis of rotation R₃ unconstrained, that is, with an angular excursion A₃ of 360°.

[0090] Appropriately, the support element 6 may consist of a pair of shaped arms 15, 16, one of which 15 has one end 7 anchored to the articulation 4, while the other 16 has one end 8 anchored to the chair structure.

[0091] As best seen in Figure 1 , the arm 16 anchored to the chair/armchair structure is placed inferior to arm 15 intended to support the articulation 4 and the shelf 2.

[0092] Both arms 15, 16 have an essentially "L" shape, that is, each is defined by a pair of mutually joined sections that develop mutually orthogonal directions.

[0093] Appropriately, arms 15, 16 may be formed from piece of tube bent to define an essentially "L" shape.

[0094] The arm 15 also has an end 19 intended to be coupled with an end 20 of the other arm 16.

[0095] The coupling of the ends 19, 20 of the pair of arms 15,16 is of the rotatable type, that is, each arm 15, 16 can rotate relative to the other around a fourth axis of rotation R4 passing through the mutually coupled ends 19, 20.

[0096] In general, the sections of arms 15,16 comprising ends 19, 20 are essentially straight so as to define along their development, a fourth axis of rotation R4 essentially parallel to the third axis of rotation R3.

[0097] In general, the third axis of rotation R3 is basically vertical.

[0098] In addition, the rotation of the arms 15, 16 with respect to the fourth axis of rotation R4 can occur freely and unconstrained, i.e., the upper arm 15 anchored at the articulation 4 can rotate with respect to the lower arm 16 connected to the chair/armchair structure with a range A4 of 360°.

[0099] The configuration of the tablet 1 described above enables the controlled and selective rotation of the shelf 2 around four axes of rotation:

The shelf 2 can rotate around the first axis of rotation R1 in order to assume an operative position or an inoperative position;

The shelf 2 can rotate with respect to the articulation 4 around the second axis of rotation R2;

The shelf 2 can rotate around the chair/armchair structure around the third axis of rotation R3;

The shelf 2 can rotate with respect to arm 16 of support element 6 that is anchored to the chair/armchair structure around the fourth axis of rotation R4.

[00100] The connection of tablet 1 to the chair structure of the type described above provides the greatest number of degrees of freedom in the movement of the shelf 2. Under these conditions, the shelf can be positioned either to the left or to the right of the user (rotation around the axis R3) and can be moved closer to or farther away from the user by free rotations around the axes R2 and R3. Finally, the shelf 2 can be selectively positioned in the operative/inoperative position through its rotation about the axis R1.

[00101] In addition, the tablet 1 comprises constraint means 21 suited to promote selective locking/unlocking of the shelf 2 in the operative position.

[00102] The constraint means 21 are configured to keep the shelf 2 in the operative position during the time the user is using the tablet, preventing the tablet from autonomously and suddenly returning to the inoperative position. [00103] As will be more fully described later in this description, the constraint means 21 are suited to allow the transition of the shelf 2 from the operative position to the inoperative position only as a result of a voluntary action taken by the user on certain components of tablet 1.

[00104] The constraint means 21 comprise a pin 22 anchored to the support element 6 near the end 7 of it intended to be connected to the articulation 4.

[00105] In the configuration of tablet 1 shown in Figures 1 through 9, the pin 22 is inserted inside a hole 23 formed on tubular arm 15 coupled to the articulation 4.

[00106] The fixed pin 22 may be inserted inside a hole formed on support element 6; this hole is not visible in the Figures. The length of the fixed pin 22 will be chosen so that it has a portion 24 protruding from the support element 6.

[00107] In addition, the hole will be oriented so as to allow the fixed pin 22, following its insertion, to face the protruding portion 24 toward the shelf 2 when the latter is in the operating position.

[00108] In general, the protruding portion 24 of the fixed pin 22 is oriented upward and thus faces the shelf 2 when the latter is in the operative position.

[00109] As best seen in Figure 7, the hole is formed on support element 6 at a position chosen so that the pin 22 is placed at the central portion 10 of the articulation 4, that is, downstream of sleeve 9.

[00110] In addition, the constraint means 21 comprise a shaped seat 25 formed at the articulation 4.

[00111] Such a seat 25 may be formed on the enlarged portion 10 of the articulation 4. [00112] Conveniently, the shaped seat 25 can be opened, that is, it can be formed on the enlarged central portion 10 of the articulation 4 so that only the side walls 26, 26' are expected to exist without any bottom wall.

[00113] The shaped seat 25 may be formed at the enlarged position 10 of the articulation 4 in an area suitable to provide for interaction with the protruding portion 24 of the fixed pin 22.

[00114] In the continuation of this description, and except where otherwise indicated, the expression "protruding portion of the fixed pin" will be used synonymously with the expression "fixed pin" since the interaction of the pin with other elements of the tablet can only occur at the portion of the pin that protrudes from the supporting element.

[00115] Conveniently, the absence of a bottom wall, formed on the shaped seat 25, allows the insertion of the fixed pin 22 in a pass-through manner, as best seen in the section in Figure 7.

[00116] Specifically, in the configuration of the invention shown in Figure 7, the extension of the fixed pin 22 protruding from the support element 6 is greater than the height of the seat 25: When the pin is inserted inside that the seat 25, the latter is completely crossed by it, while the end portion of the pin 22 protrudes in turn from the upper edge of the seat 27.

[00117] Specifically, it is possible to identify two distinct portions of the seat 25 each having a predetermined shape and size, the union of these portions gives the seat 25 a predetermined shaping chosen so as to promote the locking/unlocking of the articulation 4 with respect to its rotation about the first axis of rotation Ri, as will be better elucidated below.

[00118] First, the first portion 28 has a width W2 such that the fixed pin 22 can be inserted.

[00119] However, the first portion 28 of the seat 25 has a width h slightly larger than the diameter Di of the fixed pin so that it can be inserted with little clearance.

[00120] The length I2 of the first the seat 28 will be chosen to be slightly greater than at least the radius (Di/2) of the pin 22.

[00121] For example, when the fixed pin has a diameter between 5 mm and 10 mm, the first the seat may have an extension between 7 mm and 20mm.

[00122] In addition, the first portion 28 of the seat 25 has a straight development extending along a direction essentially parallel to the first axis of rotation R1.

[00123] There is also a second portion 29 of the seat 25 also having a predetermined shape, however, this second portion 29 is in communication with the first portion 28. [00124] In general, the second portion 29 of the seat 25 may also be straight.

[00125] The second portion 29, moreover, may have a width W3 slightly greater than the diameter Di of the fixed pin 22 (so as to allow it to be inserted within it) and a length I3 chosen to be at least equal to the length of the portion of the pin 22 that protrudes from the upper edge of the seat 25.

[00126] For example, if the fixed pin 22 has a diameter between 5 mm to 10 mm and an overall length between 15 mm to 25 mm, the second portion 29 may have a width W3 of slightly greater than 5 mm to 10 mm and a length I3 of not less than 30 mm to 50 mm.

[00127] Appropriately, the second portion 29 of the seat 25 may extend along a direction perpendicular to the direction of development of the first portion 28 of the seat 25.

[00128] Specifically, in the tablet configuration illustrated in Figures 1 through 9, the second portion 29 of the seat 25 develops along a direction orthogonal to the first axis of rotation R1 and the second axis of rotation R2, respectively.

[00129] In addition, the first portion 28 may be joined to the second portion 29 of the seat substantially at the centerline of the latter.

[00130] In this case, the seat 25 may have a substantially "T" plan-view shape formed by two orthogonal and mutually communicating sections represented by the first portion 28 and the second portion 29.

[00131] In addition, the first portion 28 is parallel to the first axis of rotation Ri and therefore the TT-TT plane, in addition to being a plane of symmetry for the shelf 2, can also be the plane of symmetry for the "T"-shaped seat 25.

[00132] As clearly visible in Figure 4, the seat 25 is symmetrical with respect to the TT- TT plane (just as the first portion 28 and the second portion 29 are also symmetrical with respect to that TT-TT plane).

[00133] As will be better elucidated later in this description, the articulation 4 is movable relative to fixed pin 22 in such a way as to promote selective insertion of the latter into the first portion 28 and second portion 29 of the seat 25 (and vice versa).

[00134] When the pin 22 is inserted into the first portion 28 of the seat 25, the clearance present between these two elements is particularly small, and for this reason the articulation 4 is locked in rotation about the first axis of rotation Ri.

[00135] In this condition, in the case where the user acts on the tablet by imposing a rotational torque on the shelf around the first axis Ri, the outer surface 30 of the fixed pin 22 goes immediately into abutment with the side wall 26 of the first portion 28 of the seat 25.

[00136] The abutment of the outer surface 30 of the pin 22 against the wall 26 of the first portion 28 of the seat 25 creates a constraint with respect to the rotation of the articulation 4 about the first axis of rotation Ri.

[00137] Consequently, the insertion of the fixed pin 22 within the first portion 28 of the seat 25 locks both the articulation 4 and the shelf 2 connected to it with respect to rotation about the first axis Ri thus forcing these two elements to maintain their position even when the user intends to apply rotation about the same axis Ri.

[00138] Appropriately, fixed pin 22 is inserted inside the first portion 28 when the shelf 2 is in the operative position.

[00139] When fixed pin 22 is inserted inside the second portion 29 of the seat 25, the articulation 4 is free to rotate about the first axis of rotation Ri.

[00140] In this case, in fact, if the user imparts a torque to the articulation 4 that promotes its rotation around the first axis Ri, the second portion 29 rotates around the same axis Ri and around the pin 22, which instead remains fixed because it is constrained to the support element 6.

[00141] As best seen in Figure 6, the angle between the development direction H of the second portion 29 of the seat 25 and the pin 22 varies from an initial maximum value of about 90° to a final minimum value of about 0°, during the rotation of the articulation 4 around the first axis Ri.

[00142] During this rotation, in fact, the positioning of the second portion 28 of the seat 25 with respect to the fixed pin 22 varies according as indicated below.

[00143] At the beginning of the rotation, the second portion 29 is substantially perpendicular to the pin 22. However, as the articulation 4 rotates (clockwise or counterclockwise), the second portion 29 moves closer to the pin 22 such that it assumes a position increasingly aligned with the latter.

[00144] At the end of the rotation, the second portion 29 and the pin 22 are substantially parallel, and therefore the angle p between the development direction H of the second portion 29 and the pin 22 is essentially zero. In this position, the pin 22 is completely housed inside the second portion 29.

[00145] During rotation of the articulation 4, the pin 22 always remains at least partially within the second portion 29 of the seat 25, that is, there is never a disengagement between these two elements.

[00146] However, the length l₃ of the second portion 29 of the seat 25 should be chosen so that when the user imparts clockwise or counterclockwise rotation to the articulation 4, the portion 24 of the pin 22 protruding from the support element 6 can be fully housed within the second portion 29 without coming into contact with the walls 26' or edges 27 of the latter.

[00147] For this reason, as described earlier and as a result of the fact that the pin 22 fits inside the second portion 29 of the seat 25 at the centerline of the latter, the length l₃ of the second portion 29 must be at least twice the length U associated with the protruding portion 24 of the fixed pin 22.

[00148] In this way, the articulation 4 will be able to rotate until the pin 22 is housed totally within the second portion 29, so that an essentially zero angle p is defined with the second portion 29.

[00149] Appropriately, due to the above, when the fixed pin 22 is inserted into the second portion 29 of the seat 25, the shelf 4 can rotate between the operative and inoperative positions (and vice versa).

[00150] In the operative position, the development direction H of the second portion 29 of the seat 25 is basically orthogonal to the pin 22, while in the inoperative position the development direction H is basically parallel to the pin 22.

[00151] The rotation of the articulation 4 between the operative and inoperative positions (and thus the rotation of the shelf 2) can be imparted with both directions of rotation (clockwise/counterclockwise) since the second portion 29 of the seat 25 is essentially symmetrical with respect to the symmetry plane TT-TT passing through it.

[00152] In addition, the tablet includes actuating means 31 suited to promote controlled movement of the articulation 4 and/or the pin 22 relative to the support element 6 in order to promote selective insertion of the fixed pin 22 within the first portion 28 of the seat 25, or within the second portion 29 of the seat 25.

[00153] In other words, the actuating means 31 enable the movement of the seat 25 obtained on the articulation 4 to be promoted so as to determine in which of the two portions 28, 29 the fixed pin 22 is inserted.

[00154] As described above, when fixed pin 22 is inserted into the first portion 28 of the seat 25, the shelf 2 is in the operative position and the articulation 4 is locked in rotation; while at the time when the fixed pin 22 is inside the second portion 29 of the seat 25, it is possible to promote the rotation of the shelf 2 around the first axis of rotation Ri between the two operative/inoperative positions.

[00155] Drive means 31 are user-activated to promote the selective passage of the shelf 2 from the operative position to the inoperative position.

[00156] In fact, to unlock the rotation of the shelf 2 that is in the operative position, the user is required to interact with the actuating means 31 in order to impart a controlled movement to the articulation 4 suitable for promoting the passage of the fixed pin 22 from the first portion 28 of the seat 25 to the second portion 29 of the seat 25.

[00157] In the tablet configuration shown in the Figures, the seat 25 has a substantially "T" shape formed by the first portion 28 and the second portion 29, these portions are, moreover, offset along the first axis of rotation Ri.

[00158] For this reason, the actuating means 31 may be configured to promote the selective translation of the articulation 4 relative to the fixed pin 22 along a direction substantially parallel to the first axis of rotation Ri.

[00159] Referring to Figure 3, the first portion 28 of the seat 25 is in the forward position (i.e. facing sleeve 9) compared to the second portion 29 of the seat 25.

[00160] Thus, in this case, the actuating means 31 allow the articulation 4 to make a translation along the first axis of rotation Ri with a predetermined excursion sufficient to allow the pin to fit into both portions 28, 29 of the seat 25.

[00161] Specifically, to promote the housing of the pin 22 from the first portion 28 to the second portion 29, it is necessary to impart a translation of the articulation along the first axis Ri with a direction that promotes the approach of the second axis of rotation R2 to the fixed pin 22.

[00162] Conversely, in order to promote the housing of the pin Ri from the second portion 29 of the seat 25 to the first portion 28 of the seat 25, it is necessary to impart a translation of the articulation along the first axis Ri in the opposite direction, that is, by promoting the movement of the second axis of rotation R2 away from the fixed pin 22.

[00163] The translation of the articulation along the first axis Ri is promoted by the user as a result of a force applied to the shelf 2; the anchoring of the shelf 2 to the articulation 4 allows the force generated by the user to be transferred to the latter so as to promote its translation with respect to the first axis Ri.

[00164] Conveniently, the actuating means 31 may comprise a spring 32 having one end 34 acting on the articulation 4 and an opposite end 33 acting on support element 6 or fixed pin 22.

[00165] As best seen in Figure 7, the function of spring 32 is to hold the articulation 4 in a reference position.

[00166] Specifically, spring 32 acts on the articulation 4 so as to maintain the insertion of the pin 22 inside the first portion 28. In other words, the spring 32 enables the articulation 4 to keep the shelf 2 in the operative position by preventing the pin 22 from slipping out of the first portion 28 of the seat 25 without the user having made a voluntary action on the actuating means 31.

[00167] Therefore, the action of the spring 32 prevents the unexpected and unwanted passage of the shelf 2 from the operative position to the inoperative position.

[00168] In a preferred tablet configuration, the spring 32 will be inserted into a housing 35 partly formed on the articulation 4 and partly formed by the inner tubular cavity of support element 6.

[00169] Provision can be made for the use of a bushing 36 intended to be inserted inside the tubular cavity of support element 6 (generally consisting of arm 15 supporting the articulation 4).

[00170] The spring 32 may be inserted on such a bushing 36 and the latter may comprise a stop wall 37 for the end 33 of the same spring 32.

[00171] When the first portion 28 of the seat 25 is placed upstream relative to the second portion 29, as illustrated in Figure 7, spring 32 is preloaded in compression so as to apply an outward-acting force to the articulation 4 that is suitable for promoting the movement of the second axis of rotation R₂ away from the pin 22.

[00172] In this condition, the pin 22 remains inserted inside the first portion 28 of the seat 25 when the shelf 2 is in the operative position.

[00173] In an alternative version of the invention, it is possible to provide for the use of a spring 32 preloaded in tension: in this case, portions 28, 29 of the seat 25 are reversed from what can be seen in Figure 7, that is, the second portion 29 is placed upstream relative to the first portion 28.

[00174] The action of a preloaded spring 32 in tension allows an inward-oriented force to be applied such that it promotes the approach of the second axis of rotation R₂ with respect to the pin 22.

[00175] Therefore, also in this case, the pin 22 remains inserted within the first portion 28 of the seat 25 when the shelf 2 is in the operative position.

[00176] Finally, in the tablet configuration illustrated in Figures 1 through 9, it is possible to provide for the use of a spring 35 arranged within the tubular support element 6 on the opposite side from the pin 22 (i.e. , on the opposite side from the configuration visible in Figure 7).

[00177] In addition, a simplified version of the actuating means 31 may be provided such that the spring 32 is housed within the tubular cavity of the support element 6; in this case, the end of the spring 33 is suited to come into contact with the portion of the pin 22 inserted within the tubular arm.

[00178] Conveniently, the actuating means 31 comprise a shaped recess 38 formed into the shelf 2.

[00179] Specifically, recess 38 allows the insertion of the end 24 of the fixed pin 22 protruding from the shaped seder 25.

[00180] The recess 38 is formed on the lower surface 5 of the shelf 2 at which the articulation 4 is mounted.

[00181] The rotation of the shelf 2 around the second axis of rotation R2 promotes the subsequent rotation of recess 38 around the fixed pin 22.

[00182] In a tablet configuration not illustrated in the Figures, the size and shape of recess 38 may be chosen such that it rotates about the second axis R2 for the most of the angular excursion A2 without any edge or wall of the recess contacting the fixed pin 22.

[00183] In an alternative embodiment shown in Figure 8 and Figure 9, (representing, however, one among several embodiments of the recess 38) there is a semicircular edge 39 intended to contact the outer surface 30 of the fixed pin 22 when the shelf 2 rotates about the second axis of rotation R2.

[00184] A possible advantage related to the presence of a contact edge 39 is to make on the same a small central notch 44 suited to engage removably with the end of the pin 22 inserted in the recess 38 so as to define a reference point during the rotation of the shelf 2 around the second axis of rotation R2. For example, notch 44 could be placed in the centerline of the edge 39 (so as to signal to the user a starting position with respect to the symmetrical rotation of the shelf 2 about the axis R2). Alternatively, notch 44 could be placed near the end portions 41 , 42 of edge 39 so as to signal to the user the imminent transition of the shelf 2 from the active position to the inactive position.

[00185] Therefore, in this case, the semicircular surface 39 bounding the recess 38 slides on the fixed pin 22 during the rotation of the shelf 2 around the second axis of rotation R2.

[00186] Alternatively, the shaped recess 38 may comprise a semicircular groove defined by a pair of parallel edges and suitable for housing within it the end portion of the fixed pin 22. [00187] During the rotation of the shelf 2, one or both edges defining the groove may contact the outer surface 30 of the fixed pin 22 so as to slide with respect to it.

[00188] The configuration of recess 38 comprising a groove is shown in Figure 9.

[00189] Preferably, the actuating means 31 may include at least one guide surface 40 suitable for interacting with the fixed pin 22 when the shelf 2, during rotation about the second axis R2, reaches an angular excursion A2 close to its maximum value.

[00190] In general, actuating means 31 comprise a pair of guide surfaces 40: one such guide surface 40 is suited to interact with the pin 22 when the shelf rotates clockwise, while the other of such surfaces 40 is suited to interact with the pin 22 when the shelf 2 rotates counterclockwise.

[00191] The guide surfaces 40 can be substantially straight and both oriented so as to be convergent toward a point P located toward the center of the shelf 2 in order to promote, during the rotation of the shelf 2, a decrease in the distance between the fixed pin 22 and the second axis of rotation R2.

[00192] In the tablet configuration shown in the Figures, the straight guide surfaces 40 have one end 41 , 42 in common with the end point of the semicircular edge of the recess. [00193] When the user acts on the shelf 2 in such a way as to cause it to rotate about the second axis of rotation R2, the semicircular edge 39 of recess 38 slides on the outer surface 30 of the pin 22 (without any change in the distance between this component and the second axis of rotation R2) until it reaches one of its ends 41, 42.

[00194] If the user acts on the shelf 2 in such a way as to promote its rotation beyond the ends 41, 42 of the semicircular edge 39, the guide surface 40 that is in the proximity of the pin 22 begins to slide on the outer surface 30 of the latter, so as to cause that the pin 22 to approach the second axis of rotation R2.

[00195] The guide surface 40, however, has a straight rather than semicircular course and ends at an end 43 suitable for forming an abutment for the pin 22; this end 43 faces inward from the shelf 2 and is arranged opposite the ends of the semicircular edge 38.

[00196] This configuration of the guide surface generates, in addition to the rotation of the shelf 2 around the second axis of rotation R2, also a translation of the shelf 2 itself along a direction parallel to the first axis of rotation R1.

[00197] In other words, the sliding of the guide surface 40 of the above type (straight and converging inward) on the fixed pin 22 varies the motion to which the shelf 2 is subjected by transforming it from a pure rotational motion with respect to the second axis of rotation R2 to a roto-translational motion with respect to the second axis of rotation R2 and the first axis R1.

[00198] When guide surface 40 slides relative to the pin 22, the articulation 4 undergoes translatory motion along a direction parallel to the first axis of rotation Ri_;thus, the pin 22 itself can selectively fit within the first portion 28 or within the second portion 29 of the seat 25.

[00199] If the guide surface 40 slides on the pin 22 with a sliding direction such that its end 43 approaches the pin, the articulation translates along the first axis Ri with a direction such that the second axis of rotation R2 approaches the fixed pin 22.

[00200] During this translatory movement of the articulation, the pin 22 progressively protrudes from the first portion 28 of the seat 25 to fit within the second portion 29.

[00201] Conversely, when the guide surface 40 slides on the pin 22 so as to move the latter away from its end 43, the articulation can translate along the first axis R1 (recalled by spring 32) with a direction such that the second axis of rotation R2 moves away from the fixed pin 22.

[00202] In this case, if the pin 22 as a result of the rotation of the shelf 2 around the axis of rotation R2 is again found to assume a position aligned with the first portion 28 of the seat 25, such pin 22 tends progressively to protrude from the second portion 29 of the seat 25 to fit inside the first portion 28.

[00203] Because of the above, through user-promoted rotation at the shelf 2, automatic translation of the articulation 4 can be promoted so that fixed pin 22 can selectively engage the first portion 28 or second portion 29 of the seat 25.

[00204] In this way, by rotation of the shelf 2 and without directly acting on the articulation, the user can either lock this component in rotation (inactive position) or allow it to rotate around the first axis of rotation R1 (passing from active to inactive position).

[00205] It is possible to provide an alternative recess 38 configuration to the one described above that is distinguished by having a non-symmetrical geometry (this configuration is not illustrated in the Figures). The non-symmetrical recess 38 involves a single guide surface 40 made at the right end 41 or the left end 42 of the semicircular edge 39. In this case, the automatic translation of the articulation 4 is promoted only when the user rotates the shelf in the direction suitable to bring the guide surface 40 against the fixed pin 22.

[00206] In addition, in this configuration of the recess 38, a stroke surface (not shown in the Figures) may be made substantially radial to the axis of rotation R2 and capable of coming into contact with the fixed pin 22 when the user rotates the shelf 2 in the opposite direction from the direction that allows the guide surface 40 to come into abutment with the pin itself.

[00207] The function of the stroke surface is to define an end stop in the rotation of the shelf 2 around the second axis of rotation R2 when the direction of rotation of that the shelf 2 is opposite to that which brings the guide surface 40 closer to the pin 22.

[00208] If the user promotes the rotation of the shelf 2 around the axis R2 in a first direction of rotation (such that the pin 22 approaches the guide surface 40), at the end of this rotation the interaction between the pin 22 and guide surface 40 is established so as to promote the passage of the shelf 2 from the operative position to the inoperative position. Conversely, if the shelf rotates about the axis R2 in the opposite direction, at the end of the rotation, the pin 22 comes into contact with the stroke surface, which, therefore, stops the rotation of the same in a limit end position.

[00209] The tablet configuration illustrated in Figures 1 through 9 involves making a shaped seat 25 essentially symmetrical with respect to the TT-TT plane of symmetry.

[00210] More generally, the seat 25 consists of a first portion 28 and a second portion 29 extending along respective directions of development that are substantially orthogonal to each other and such that they form a "T" shape in plan symmetrical with respect to the TT-TT plane (visible in Figure 4).

[00211] Specifically, the first portion 28 of the seat 25 may extend along a development direction parallel to the first axis of rotation R1 (and lie on the TT-TT plane of symmetry), while the second portion 29 of the seat 25 extends along a development direction orthogonal to the first axis of rotation R1.

[00212] This configuration of the seat 25, combined with a recess provided with a pair of guide surfaces 40, enables the shelf 2 to automatically pass from the operative to the inoperative position when it rotates about the second axis of rotation R2 in both directions of rotation (clockwise and counterclockwise).

[00213] However, it is possible to provide an alternative configuration of the seat 25, suitable for allowing the automatic passage of the shelf 2 from the operative position to the inoperative position only when it rotates around the axis R2 with certain direction of rotation (clockwise, or counterclockwise).

[00214] In this case, the seat 25 consists of a first portion 28 extending in a direction substantially parallel to the axis R1 and a second portion 29 extending in a direction orthogonal to the first portion 28, so as to define a seat 25 having a substantially "L" shape in plan.

[00215] Thus, in this case, the passage of the shelf 2 from the operative position to the inoperative position occurs only when the latter rotates with a direction that allows the pin 22 to fit into the second portion 29 of the seat.

[00216] If the substantially "L"-shaped seat 25 has a second portion 29 positioned to the left of the first portion 28 (with respect to the plan view from above, with the first portion 28 positioned at the bottom), the passage of the shelf 2 from the operative position to the inoperative position occurs when the user rotates the latter around the second axis of rotation R₂ in a clockwise direction.

[00217] Conversely, if the substantially "L"-shaped seat 25 has a second portion 29 positioned to the right of the first portion 28 (with respect to the plan view from above, with the first portion 28 positioned at the bottom), the passage of the shelf 2 from the operative position to the inoperative position occurs when the user rotates the latter around the second axis of rotation R2 in a counterclockwise direction.

[00218] Conveniently, when the seat 25 has an "L" shape in plan, the shaped recess 38 may be of the non-symmetrical type (as described above) so as to provide for the realization of a single guide surface 40 positioned in the direction of rotation concordant with that which allows the insertion of the pin 22 within the second portion 29 of the seat 25.

[00219] There is also a variation of the configuration of tablet 1 described above and illustrated in Figure 7.

[00220] This variant can be seen in Figure 7 bis.

[00221] The variant visible in Figure 7 bis is quite similar to the one visible in Figure 7 except for the configuration provided for the pin 22.

[00222] In fact, in this case, the extension of the pin 22 is such that it does not protrude superiorly from the shaped seat 25 (and in particular, this pin 22 does not protrude superiorly either from the first portion 28 or from the second portion 29 of this seat 25).

[00223] In other words, the configuration visible in Figure 7 bis does not include a protruding portion of the pin 22 (indicated in the different version of Figure 7 by reference number 24); instead, the end of the pin 22 always remains contained within the shaped seat 25 (and does not provide for a protruding outward from it).

[00224] In the configuration of Figure 7 bis, therefore, the selective passage of the pin 22 between the first portion 28 of the seat 25 (corresponding to the locking of the shelf 2 in the operative position) and the second portion 29 of the seat 25 (suitable for allowing the rotation of the articulation 4 from the operative position to the inoperative position) is not promoted by the interaction between the outer surface 30 of the pin 22 and the guide surface 40.

[00225] In the configuration of Figure 7 bis, in fact, the passage of the pin 22 from the first portion 28 of the seat 25 to the second portion 29 of the same the seat 25 can be manually promoted by a user exerting a force on the tablet 1 (or parts of it, e.g., the shelf 2) such that the resistance of spring 32 is overcome (i.e., by applying a compression of the same) in order to promote translation of the articulation 4 along the axis R1 so as to allow the fixed pin 22 to engage the second portion 29 of the seat 25.

[00226] This force is shown in Figure 7 bis with the arrow F.

[00227] The user, as a result of the translation of the pin 22 in the second portion 29 of the seat 25 (through the manual application of the force F), can promote the rotation of the shelf 2 between the operative and inoperative positions. [00228] When the user promotes the rotation of the shelf 2 in the opposite direction (from the inoperative position to the operative position), as soon as such shelf 2 is in the operative position, the force applied by the compressed spring 32 to the articulation 4 will be such as to promote the translation of the latter to the opposite direction from that is indicated by the arrow F, and the automatic passage of the pin 22 from the second portion 29 of the seat to the first portion 28 (so as to generate the locking of the shelf 2 in the operative position).

[00229] As described earlier, this version of the invention does not provide for the interaction of the pin 22 with guide surfaces 40.

[00230] For this reason, therefore, the of tablet 1 shown in Figure 7 bis involves the construction of a shelf 2 of the full type, that is, without the recesses 38.

[00231] In an alternative version not shown in the Figures, tablet 1 may have the same configuration visible in Figure 7 bis except that the shelf 2 may equally comprise recess 38. In this case, however, the pin 22 does not interact with the guide surfaces 40 and the movement of such shelf 2 may be promoted in the same way already described for the version of the tablet 1 shown in Figure 7 bis.

[00232] In fact, the dimensions of the pin 22 are such that it remains inside the seat 25 in any position (operative, inoperative, in the passage between operative/inoperative and that inoperative/operative) and, therefore, the end of said pin 22 never interacts with the shelf 2.

[00233] An alternative configuration of the tablet that is the subject of this invention is shown in Figure 10.

[00234] This different tablet configuration is of the type previously described, except for the parts described in detail here.

[00235] Specifically, the tablet in Figure 10 provides a pair of the pins 22, 22' (both fixed relative to the support element 6) intended to interact with the shaped seat 25 and shaped recess 38, respectively.

[00236] The first pin 22 is inserted inside the seat 25 and has a length such that it does not protrude from it. The function of the pin 22 is to rotationally lock/unlock the shelf 2 with respect to the axis Ri when it is selectively inserted into the first portion 28 or the second portion 29 of the seat 25.

[00237] The second pin 22’, on the other hand, interacts exclusively with recess 38, and is not passing through the seat 25. This second pin 22’ has a longer length than the first pin 22; this length is chosen so that its outer surface 30 can interact with the guide surface 40 obtained in the recess 38.

[00238] In the tablet configuration shown in Figure 10, the rotational locking/unlocking of the shelf 2 around the first axis of rotation Ri and the selective translation of the articulation 4 in order to promote the passage of the shelf 2 between the operative and inoperative positions are no longer made through a single pin 22 (as in the case of the configuration in Figure 1 - 9), but rather these functions are delegated to a pair of the pins 22, 22'.

[00239] Also in this case, the actuating means 31 have a spring 32 suited to act directly on the articulation 4 so as to keep it in a default position in which the first pin 22 is inserted into the first portion 28 of the seat 25.

[00240] In the configuration of tablet 1 illustrated in Figures 1 through 10, the first pin 22 is fixed, i.e., that the pin 22 is integral to the support element 6 and cannot be displaced during the use of the shelf (in this case, it is the articulation 4 that is movable in translation and rotation with respect to the pin 22). Also in the tablet configuration shown in Figure 10, both the pins 22, 22' are fixed and integral to support element 6 (the articulation 4 is movable in translation and in rotation with respect to these the pins 22, 22').

[00241] Additional configurations of tablet 1 can be provided according to the invention, best illustrated in Figure 11 and Figure 12.

[00242] This different tablet configuration is of the type previously described, except for the parts described in detail here.

[00243] In these configurations it is provided the use of a lock-pin 47 and a single pin 22 mounted on the support element 6 in a movable manner. The lock-pin 47 is inserted within an opening 48 formed on the sleeve 9 to allow rotation of the articulation 4 about the first axis of rotation Ri. The opening 48 also develops along a direction substantially parallel to the second portion 29 of the seat 25 so as to lock the articulation with respect to a translation along the first axis of rotation Ri.

[00244] The support element 6 may comprise a single slot 45 or a pair of slots 45 extending along a direction substantially parallel to the first axis of rotation Ri.

[00245] The slots 45 may be obtained in proximity of the end 7 of the support element 6 connected to the articulation 4.

[00246] The pin 22 is inserted in a passing-through manner into the support element 6 through at least one of the slots 45. Said pin 22 has an upper protruding portion 24 intended to be inserted into the slot 25 in a pass-through manner and possibly protrude from it, if a recess is provided.

[00247] In the configuration shown in Figure 11 , the pin 22 is mounted on the bushing 36 and can slide within a single slot 45 formed on the support element 6. Thus, in this configuration, the pin 22 is movable relative to the support element 6.

[00248] The sliding of the pin 22 in the slot 45 may be selective in that this pin 22 may translate along a direction parallel to the first axis of rotation Ri due to the action exerted on it by the actuating means 31.

[00249] Specifically, the spring 32 has one end 33 interacting with the articulation 4 and an opposite end interacting with the bushing 36 (integral with the pin 22).

[00250] Therefore, the action of the spring 32 will be such as to promote the application on the pin 22 of an outwardly oriented force such as to keep the latter within the first portion 28 of the seat 25.

[00251] In the configuration of the invention illustrated in Figure 11, the actuating means 31 provide for the realization of the shaped recess 38; for this reason, the selective insertion of the pin 22 within the second portion 29 of recess 25 will be promoted when, as a result of the rotation of the shelf 2 around the second axis of rotation R2 and the consequent interaction of the outer surface 30 of the pin 22 with the guide surfaces 40, the spring 32 undergoes compression and the pin 22 slides within the slot 45) so as to position itself within the second portion 29 of recess 25).

[00252] In the following is described the configuration of tablet 1 shown in Figure 12.

[00253] In this case, a pair of openings 45 is provided, and the pin 22 has a portion of the lower end 46 that protrudes from the support element 6 and is intended to be grasped by the user. The latter may promote the sliding movement of the pin 22 within slots 45 with respect to a direction parallel to the first axis of rotation R1.

[00254] In this way, the selective insertion of the upper protruding portion 24 of the pin 22 within the first portion 28 or second portion 29 of the seat 25 will be directly promoted by the user through the translation of the pin 25 within slots 45 between the two limit positions defined by them.

[00255] Specifically, the pin 22 is inserted into the first portion 28 of the seat 25 when the same is in the farthest limit position with respect to the second axis of rotation R2, while the same is inserted into the second portion 29 of the seat 25 when it is in the nearest limit position with respect to the second axis of rotation R2.

[00256] Therefore, in the configuration of tablet 1 shown in Figure 11, the insertion of the pin 22 into the first portion 28 or the second portion 29 of the seat 25 does not occur automatically during the rotation of the shelf 2 around the second axis of rotation R2, as described in the configurations of Figure 1 - 9.

[00257] Indeed, in this case, the passage of the pin 22 within the first portion 28 or the second portion 29 of the seat 25 occurs manually as a result of the translation promoted on the pin 22 itself by the user who has previously grasped the lower end portion 46 of the pin 22.

[00258] In this configuration, moreover, recess 2 may be devoid of the guide walls 40 and comprise only a stroke wall interacting with the upper end portion 24 of the pin 22 so as to determine an end stop in the rotation of the shelf 2 around the second axis of rotation R2.

[00259] In the tablet configuration shown in Figure 12, the articulation 4 is fixed relative to support element 6, and the only movable element is the pin 22. In other words, the pin 22 is movable relative to support element 6.

[00260] The spring 32 of the constraint means 31 then acts on the pin 22 exerting a force on it suitable for keeping its upper end portion 24 within the first portion 28 of the seat 25.

[00261] When the user intends to promote the sliding of the pin 25 inside slots 45 (for the purpose of inserting the upper end portion 24 of the pin 22 into the second portion 29 of the seat 25), it will have to overcome the opposite resistance offered by spring 32 while the passage of the pin 22 from the second portion 29 of the seat 25 to the first portion 28 of the seat 25 may be substantially automatic due to the spring force exerted by spring 32 on the pin 22 itself.

[00262] Figures 13 through 16 illustrate some configurations of mounting the tablet described above to a chair structure provided with a sitting area that is substantially symmetrical with respect to a centerline plane M.

[00263] The configuration in Figure 13 illustrates a connection of tablet 1 to the chair structure made by means of a straight support element 6, lacking sections 15 and 16 and rigidly connected to the chair structure itself.

[00264] In this case, the shelf 2 can only rotate with respect to two axes: the first axis of rotation R1 and the second axis of rotation R2.

[00265] In the version shown in Figure 14, tablet 1 is connected to the chair structure through a support element 6 consisting of one of the sections 15 and 16 mounted so as to be rotatable with respect to the fourth axis of rotation R4.

[00266] In the version shown in Figure 15, tablet 1 is connected to the chair structure through a support element 6 consisting of one of the sections 15 and 16 mounted so as to be rotatable with respect to the fourth axis of rotation R3.

[00267] In this case, the shelf 2 can rotate with respect to the first axis of rotation R1, with respect to the second axis of rotation R2, and with respect to the fourth axis of rotation R₃.

[00268] Finally, in the version shown in Figure 16, the connection to the chair structure of a tablet 1 of the type shown in Figure 1 is schematized. For this reason, in this version, the shelf 2 can selectively rotate around all axes of rotation R1 - R4.

[00269] The present invention is realizable in other variants all within the scope of the inventive features claimed and described; these technical features may be replaced by different technically equivalent elements and the materials used; the shapes and sizes of the invention may be any as long as they are compatible with its use. [00270] The numbers and reference marks inserted in the claims and description are intended only to increase the clarity of the text and should not be considered as limiting the technical interpretation of the objects or processes identified by them.

Claims

1. A tablet for supporting one or more objects, wherein the tablet is anchorable to a chair or armchair structure, such tablet comprising:

- a shelf (2) suited to allow the positioning of one or more objects;

- an articulation (4) anchored to said shelf (2) and suited to rotate around a predetermined first axis of rotation (Ri) to allow selective rotation of said shelf (2) between an inoperative and an operative position;

- a support element (6) having ends (7, 8) connected, respectively, to said articulation (4) and chair or armchair structure;

- constraint means (21) suited to promote the selective locking/unlocking of said shelf (2) in/from said operative position, said constraint means (21) comprising a pin (22) operatively connected to said support element (6) in proximity of the end (7) connected to said articulation (4), and a shaped seat (25) formed in said articulation (4) and capable of allowing the insertion of said pin (22), said shaped seat (25) comprising:

- a first portion (28) suited to allow the insertion of said pin (22) with reduced clearance so as to define with the same a rotational constraint for said articulation (4) around said first axis of rotation (Ri ) and lock the shelf (2) in said operating position;

- a second portion (29) having a predetermined length (I3) suited to allow the insertion of said pin (22), said second portion (29) of said seat (25) being suited to selectively rotate around, respectively, to said first axis of rotation (Ri) and to said pin (22) during the rotation of the articulation (4) so as to allow the partial or total insertion of said pin (22) into said second portion (29) and the passage of the shelf (2) from said operative/ inoperative position to said inoperative/operative position;

- actuating means (31) suited to promote the controlled movement of said articulation (4) and/or said pin (22) with respect to said support element (6) so as to promote the selective insertion of said pin (22) into the first portion (28) or in the second portion (29) of said seat (25); wherein said shelf (2) is rotatably anchored to said articulation (4) so as to rotate selectively with respect to said articulation (4) around a second axis of rotation (R2) substantially orthogonal with respect to the first axis of rotation (Ri) .

2. Tablet according to claim 1 , characterized in that said first portion (28) of said shaped seat (25) and said second portion (29) of said shaped seat (25) extend along directions substantially orthogonal to each other.

3. Tablet according to one or more of the preceding claims, characterized in that said shelf (2) is substantially symmetrical with respect to a plane of symmetry (TT- TT), said first axis of rotation (Ri) being contained in said plane of symmetry (TT-TT).

4. Tablet according to claim 3, characterized in that said second axis of rotation (R2) lies on said plane of symmetry (TT-TT), said shelf (2) being rotatable around said second axis of rotation (R2) with a predetermined angular excursion (A2) substantially symmetrical with respect to said plane of symmetry (TT-TT).

5. Tablet according to one or more of the preceding claims, characterized in that said actuating means (31) are suited to promote the selective translation of said articulation (4) with respect to said support element (6) along a direction substantially parallel to said first axis of rotation (R1).

6. Tablet according to claim 5, characterized in that said actuating means (31) comprise a shaped recess (38) formed in said shelf (2), said pin (22) being inserted in a passing-through manner into said shaped seat (25) and having a portion (24) at least partially inserted within said shaped recess (38).

7. Tablet according to claim 6, characterized in that said actuating means (31) comprise at least one guide surface (40) formed in said recess (38) and suited to interact with the outer surface (30) of said pin (22) during rotation of said shelf (2) around said second axis of rotation (R2), said at least one guide surface (40) being slidable on said pin (22) during rotation of said shelf (2) to generate the translation of said shelf (2) and said articulation (4) along the direction substantially parallel to said first axis of rotation (R1) by promoting the selective insertion of said pin (22) into said first portion (28) or into said second portion (29) of said seat (25).

8. Tablet according to one or more of claims from 1 to 4, characterized in that said actuating means (31) are suited to move said pin (22) with respect to said support element (6) along a direction substantially parallel to said first axis of rotation (R1).

9. Tablet according to claim 8, characterized in that said actuating means (31) comprise at least one slot (45) formed on said support element (6) in proximity of the end (7) connected to said articulation (4), said pin (22) being passing-through and slidable inserted in said at least one slot (45) and having an end portion (46) operatively graspable by a user so as to slide in said at least one slot (45) between two limit positions suited to define the insertion of said pin (22) into the first portion (28) or into the second portion (29) of said shaped seat (25).

10. Tablet according to one or more of the preceding claims, characterized in that said actuating means (31) comprises a return spring (32) acting on said pin (22) and/or said articulation (4) to exert a return force suited to promote the retention of said fixed pin (22) within said first portion (28) of said seat (25).

11 . Support tablet according to one or more of the preceding claims, wherein the chair structure is provided with a sitting area substantially symmetrical with respect to a centerline plane (M), characterized in that said support element (6) is rotatably anchored to the chair or armchair support structure, said support element (6) being rotatable around a third axis of rotation (R3) passing through the end (8) of said support element anchored to the chair or armchair structure at the centerline plane (M) of the structure.

12. Tablet according to one or more of the preceding claims, characterized in that the support element (6) comprises a pair of arms (15, 16) mutually rotatable and coupled to each other at a respective end (19, 20), said arms (15, 16) being mutually rotatable around a fourth axis of rotation (R4) substantially parallel to said second axis of rotation (R2) when said shelf (2) is in the operative position.

13. Tablet according to claim 12, characterized in that one arm (15) of said pair has an end (7) connected to said articulation (4), and the other arm (16) of said pair has an end (8) anchored to the chair or armchair structure in such a manner to be rotatable around said third axis of rotation (R3).

14. A chair structure comprising:

- a support frame defining a base intended to rest on the ground, a sitting area and a backrest;

- a support tablet (1) associated with said frame to selectively support one or more objects; characterized in that said support tablet (1) is of the type according to one or more of the preceding claims.