Connection device for a treatment bed, system and assembly method

Description

TECHNICAL FIELD

[0001] The present invention relates to connecting device for connecting in an articulated manner one or more legs of a treatment bed with a tubular element of a base support of the treatment bed. The invention further relates to a system comprising one or more connecting devices, a treatment body comprising one or more legs and a base support comprising one or more tubular elements.PRIOR ART

[0002] The present disclosure pertains to the field of treatment beds, particularly focusing on quick connection and disconnection devices for articulately linking treatment bed legs to tubular elements of a base support. Various prior art solutions have been explored in this domain, aiming to enhance the ease of assembly, adjustability, and functionality of treatment beds. Examples of such connection elements are known from GB2403141, EP1920747, and US5791233. The following overview highlights some of these prior art solutions along with their associated disadvantages.

[0003] Traditional methods for connecting treatment bed legs to base support tubular elements involve the utilization of simple bolt and nut connections. While these mechanisms are widely used in static treatment bed configurations, they exhibit notable limitations in the context of dynamic treatment bed configurations: complex assembly (the assembly process necessitates multiple components, leading to prolonged setup times and intricate maintenance procedures), limited adjustability (achieving fine adjustments to bed height or angle requires disassembling bolts and nuts, posing challenges for medical personnel) and tool dependency (proper assembly and adjustment often mandate specialized tools, introducing further complexity and prerequisites).

[0004] Another approach in the prior art involves hinged mechanisms equipped with locking pins, intended to expedite assembly and disassembly while providing a degree of adaptability. However, hinged mechanisms often impose restrictions on the available range of movement and adjustable angles, constraining the versatility of treatment bed configurations. Further, the incorporation of moving parts and locking mechanisms introduces mechanical intricacies that can elevate manufacturing complexity and introduce potential points of failure.

[0005] Given the inherent disadvantages associated with these prior art solutions, an evident need remains for an improved quick connection and disconnection device that addresses these challenges, while concurrently providing elevated user-friendliness, robustness, and adaptability in the context of treatment bed configurations.SUMMARY OF THE INVENTION

[0006] The present invention addresses the problem of providing a connecting device suitable for allowing a quick connection and a quick disconnection between a treatment bed and its base support. In particular, the treatment bed comprises one or more legs and the base support comprises one or more tubular elements (preferably configured as respective cylindrical tubular elements), wherein the connecting device according to the invention is configured to provide a quick connection and quick disconnection between the one or more legs (preferably two) and one tubular element.

[0007] Thus, a first aspect of the invention refers to a connecting device for articulated connection between one or more legs of a treatment bed and a tubular element of a base support of the treatment bed (i.e., the device is suitable for connecting in an articulated manner both elements). The tubular element may be configured as a straight tubular section comprising two respective ends.

[0008] In the context of the present invention, a treatment bed may be interpreted as referring to a stretcher, a couch or a litter on which a user rests or receives treatment (e.g. a medical treatment, such as a massage or a therapeutical treatment). The connecting device comprises a central axis and at least one set (preferably two sets - i.e., a first set and a second set) of connecting elements.

[0009] The central axis (also referred to as central shaft) is configured to be arranged within (i.e. inserted into) into one of the at least one tubular element of the base support of the treatment body. The central axis comprises two respective longitudinal ends, i.e. the central axis is configured as an elongated element extending longitudinally between two respective longitudinal ends (i.e. opposed longitudinal ends). The central axis may be regarded as the axis of the articulated connection between a leg and a respective tubular element (i.e. the axis about which one or more legs of the treatment bed are articulated with respect to one respective tubular element of the base support). However, since the central axis may be configured to be rotatable together with some of the elements of the connecting device, a more precise definition may be that axis of the articulated connection is a central geometrical axis (i.e. a spatial reference not being a physical part of the invention) of the central axis (i.e. the central geometrical axis being aligned and centrally arranged with respect to the cross-section of the central axis).

[0010] Each set of connecting elements is configured to be connected to one of the respective longitudinal ends of the central axis. For example, a first set of connecting elements may be configured to be connected to one of the longitudinal ends (e.g. to a first longitudinal end) of the central axis, and a second set of connecting elements may be configured to be connected to the other longitudinal end (i.e. a second longitudinal end) of the central axis, each of said set being configured to connect a respective leg of the treatment bed to the tubular element of the support base.

[0011] It should be noted that, in those embodiments in which the connecting device comprises only one set of connecting element connected to one of the longitudinal end portions of the central axis, the other longitudinal end portion of the central axis may be comprise an auxiliary contacting element configured (i.e. shaped or formed) to prevent its insertion into the tubular element.

[0012] Each set of connecting elements comprises: a primary connecting element, a secondary connecting element, and a fastening element (also referred to as fastening connecting element).

[0013] The primary connecting element comprises a first portion (i.e. a first part) and a second portion (i.e. a second part). The first and second portions of the primary connecting element may be configured as respective opposing portions (e.g. parts or faces) of the primary connecting element. The first and the second portions may be solidly / rigidly connected to each other, e.g. by configuring the primary connecting element to be a monobloc element.

[0014] The first portion may be configured to be coaxially connected to an end of the tubular element (e.g. the first portion may be configured to be coaxially inserted within an end of the tubular element or the first portion may be configured to receive by insertion an end of the tubular element) such that the primary element is rotatable relative to the tubular element around a geometrical axis aligned with the central axis (e.g. this geometrical axis corresponding to the previously described central geometrical axis). The coaxial connection may be configured to provide a sliding (also referred to as frictional) contact between a surface of the primary connecting element and a surface of the tubular element (e.g. an inner or an outer surface / wall of the tubular element). The first portion may preferably be configured to have a circular or annular cross-section.

[0015] The second portion of the primary connecting element is configured to be connected (i.e. interlocked or engaged) by form-fitting (i.e. rigidly connected) to a connecting zone of a leg of the treatment bed. Thus, the second portion is shaped / formed to be connected by form fitting with the connecting zone of a respective leg. A connection / interlocking / engagement by form-fitting between two elements refers to a type of rigid linkage or coupling mechanism where the components are joined together based on their shapes and / or, contours that interlock or mesh with each other. This form of connection ensures that the two elements are coupled / engaged together (e.g. to rotate together about a same axis) through the inherent design of their surfaces rather than relying solely on external forces like fasteners (screws, bolts, nuts).

[0016] Thus, the second portion of the primary connecting element is configured (e.g. shaped / formed) to be connected / interlocked / engaged by form-fitting to the connecting zone of a respective leg such that, when an external force (e.g. a force applied by a user) causes a relative rotation between the tubular element and the leg about the central axis (or about the central geometrical axis of the central axis), then said form-fitting (i.e. between the second portion and the connecting zone of the leg) causes an identical relative rotation between the primary connecting element and the tubular element. In other words, the form fitting connection joins together the connecting zone of the leg and the second portion of the primary connecting element such that both elements are configured to be rotatable together relative to the tubular element (further, if the tubular element is rotated a number of degrees relative to the leg, then the tubular element is necessarily rotated the same number of degrees relative to the primary connecting element). Thereby, the above referred form-fitting connection enables the tubular element to be rotatable relative to both the primary contacting element and the leg. The relative rotation of the tubular element is about its central geometrical axis (i.e. the central geometrical axis being a spatial reference not being part of the invention), which may be arranged coincidentally with the position of the central axis.

[0017] The secondary connecting element comprises a respective first portion configured to be connected / interlocked / engaged by form-fitting (i.e. rigidly connected) to the second portion of the primary connecting element and / or to the connecting zone of the leg of the treatment bed. Since the primary connecting element is connected / interlocked / engaged by form-fitting (i.e. rigidly / solidly connected) to the connecting zone of the leg (thereby both elements being rigidly connected to each other forming a rigid group), then the connection by form-fitting of the first portion of the secondary connecting element to the second portion of the primary connecting element and / or to the connecting zone of the leg ensures that the secondary connecting element is rigidly connected to said rigid group. Thus, a rotation of the tubular element relative to the leg (as previously described) is also a rotation of the tubular element relative to the secondary connecting element. Thus, the primary connecting element, the leg and the secondary connected element are configured to be rotatable together relative to the tubular element (i.e. which may be alternatively interpreted such that the tubular element is rotatable relative to the interconnected group which comprises the primary connecting element, the leg, and the secondary connecting element)

[0018] The fastening element is configured to be connected to the respective longitudinal end of the central axis (i.e. the respective longitudinal end to which the respective set of connecting element is connected) and further configured to provide a fastening force to lock the secondary connecting element to the primary connecting element, and to lock the primary connecting element to the longitudinal end of the central axis. A fastening force, also known as a clamping force or tightening force, is a mechanical load applied to join two or more components together by means of fasteners like screws, bolts, nuts, rivets, or other similar devices. The primary purpose of applying the fastening force is to create a secure and stable connection between the secondary connecting element, the primary connecting element, and the respective longitudinal end of the central axis, thereby preventing relative motion or separation under the influence of external loads, vibrations, or other forces. The fastening force may be configured as a compression force.

[0019] Preferably, each of the one or more legs of the treatment bed may be configured to be solidly connected / interlocked / engaged (i.e. rigidly connected) to the treatment bed, e.g. in a vertical disposition. Preferably, each of the one or more tubular elements of the base support are arranged horizontally and transversely with respect to the treatment bed. Each of the one or more tubular elements may be connected to a respective structure (e.g. a pivoting arm) of the base support connected to the rest of the base support by means of an articulation (e.g. an articulation being configured to rotate about a geometrical axis being parallel to the tubular element, e.g. to a central geometrical axis of the tubular element).

[0020] The primary connecting element may further comprise a spacing portion arranged between its respective first and second portions. Preferably, the spacing portion may be configured (e.g. shaped and / or sized) to prevent its insertion into the tubular element (thereby making it easier to assembly the connecting device) and / or to prevent a contact between the leg and the tubular element.

[0021] Preferably, the second portion of the primary connecting element configured to be connected / interlocked / engaged by form-fitting (i.e. rigidly connected) to the connecting zone of the leg of the treatment bed may be configured such that said form-fitting connection is achieved when the connecting zone of the leg is connected to the second portion in a direction at least partially perpendicular to the central axis (e.g. a radial direction extending radially from or towards the central axis). At least partially perpendicular means that said direction is perpendicular or at least comprises a first directional component being perpendicular (while a second directional component may be non-perpendicular). The connecting zone of each leg may be arranged at a respective end portion of the leg and may be configured as (or may comprise) an open-end portion (also referred to as receiving portion) configured to receive (e.g. to engage by form-fitting with) the second portion of the primary connecting element. Preferably, said direction at least partially perpendicular to the central axis is also a direction being coincident with a direction of elongation of the respective leg (i.e. a direction extending along the leg between the treatment bed and the respective connecting zone of the leg). The contacting zone may comprise at least two longitudinal projections (i.e. aligned with the direction of elongation of the leg), such that the open-end portion is defined between the at least two longitudinal projections (e.g. the open-end portion may be configured as a fork comprising at least two longitudinal projections - e.g. fork tines - defining the open-end portion between them).

[0022] In preferred configurations, at least a part of the treatment bed is configured to remain always in a horizontal position and the legs are connected to a lower part of said horizontal part of the treatment bed and are configured to be arranged vertically (i.e. to extend along a direction of elongation being vertical, this direction being perpendicular to the central axis).

[0023] In preferred embodiments, the first portion may be configured to be inserted into the tubular element (e.g. through a respective longitudinal end of said tubular element) such that at least a part of the first portion is arranged between the central axis and an inner surface of the tubular element. Thus, said first portion of the primary connecting element may be configured as a contact interface between the connecting device and the inner surface of the tubular element configured to allow / provide a sliding contact therein. Optionally, the central axis may be prevented from contacting with the inner wall / surface of the tubular element and / or may be preferably arranged centred with respect to the inner wall of the tubular element. The sliding contact is compatible with a relative movement of the inner surface of the tubular element with respect to the primary contacting element (e.g. with respect to the first portion)

[0024] In some embodiments, the second portion of the primary connecting element may comprise (or be configured as) at least one three-dimensional geometric solid extending along a longitudinal direction of the central axis (i.e. a direction between the two respective longitudinal ends of the central axis), said solid being configured to be connected by form-fitting (e.g. by being configured to protrude and / or to comprise one or more lateral faces) to the connecting zone of the leg. This configuration provides an increased contact surface between this second portion and the connecting zone of the leg and with the first portion of the secondary connecting element. In some embodiments, the at least one three-dimensional geometric solid may be configured as at least one elliptical cylinder and / or as at least one prism a plurality of lateral faces (i.e. at least two lateral faces, which are arranged between the two bases of the prism; thus the prism having a respective length between its two bases)

[0025] Preferably, at least one of the faces of the at least one three-dimensional geometric solid may be configured as a rounded face (i.e. a curved face); and / or at least two of the faces of said one or more three-dimensional geometric solid may be separated by means of a respective rounded edge.

[0026] The first portion of the secondary connecting element may be configured such that its form-fitting connection to the second portion of the primary connecting element (e.g. to the at least one prism) and / or to the connecting zone of the leg may be achieved when the secondary connecting element is moved (i.e. to be connected therein) in a direction aligned with a longitudinal direction of the central axis. Preferably, the first portion of the secondary connecting element may be configured to be connected by form-fitting to the second portion of the primary connecting element when configured as (or comprising) at least one three-dimensional geometric solid according to any of the previously described embodiments. Thus, said at least one three-dimensional geometric solid (e.g. a prism) may be configured (e.g. sized or dimensioned) to have a length such that a first portion of said length may be configured to be in contact with the open-end portion (the receiving portion) of the leg. Optionally, the at least one three-dimensional geometric solid may be configured such that a second portion of said length may be in contact with the first portion of the secondary connecting element. However, when there is no optional second portion of the length, then the first portion of the length may be coincident with the length of the three-dimensional geometric solid, i.e. with the total length of the three-dimensional geometric solid.

[0027] The first portion of the secondary connecting element may comprise one or more locking elements configured to be connected to corresponding one or more locking elements of the connecting zone of the leg. The connection (e.g. by interlocking) between the respective locking elements of the secondary connecting element and the leg locks the connecting zone of the respective leg with respect to the connecting device such that the leg is prevented from moving relative to the connecting device in a direction being perpendicular (i.e. a direction extending radially from or towards the central axis) to the central axis.

[0028] Preferably, the one or more locking elements of the first portion of the secondary connecting element may comprise at least one protrusion (e.g. a pin) and / or at least one recess (e.g. at least one hole) configured to be connected to the respective one or more locking elements of the connecting zone of the leg, which may be correspondingly configured (e.g. shaped or formed) to engage with the locking elements of the first portion of the secondary connecting element. In a preferred configuration, the one or more locking elements of the connecting zone of the leg are arranged closest to the treatment bed (in a position of use) than the rest of said connecting zone (i.e. when the leg is arranged in a vertical position of use, the one or more locking elements of the connecting zone are arranged above the position of the open-end portion of the connecting zone).

[0029] The first portion of the secondary connecting element may comprise one or more projections configured to provide the form-fitting connection (e.g. rigid connection) to the second portion of the primary connecting element and / or to the connecting zone of the leg of the treatment bed. Preferably, said one or more projections are configured to embrace the second portion of the primary connecting element and / or to the connecting zone of the leg of the treatment bed. The concept embrace may be interpreted as meaning externally surrounding / contacting. Thus, in a preferred embodiment in which the second portion of the primary connecting element is configured as at least one three-dimensional geometric solid comprising a first portion its length configured to be in contact with the open-end portion (the receiving portion) of the leg (the at least one three-dimensional geometric solid optionally further comprising a second portion of its length configured to be in contact with the first receiving portion of the secondary connecting element), the first receiving portion of the secondary connecting element may be configured to engage externally (i.e. to embrace) the connecting zone of the leg, wherein the receiving portion (or open-end portion) of said connecting leg may be configured to embrace said at least one three-dimensional geometric solid.

[0030] The first portion of the primary connecting element may optionally be configured to be rigidly connected / engaged / coupled with the central axis (e.g. to the respective longitudinal end of the central axis), thereby reducing internal friction in the connecting device of the invention when the tubular element is rotated. Thus, when the tubular element is rotated relative to the primary connecting element (e.g. by an external force), then the tubular element also rotates relative to the central axis (i.e. simultaneously and to the same extent). The first portion of the primary connecting element may be configured to be rigidly engaged with the central axis by configuring the central axis to comprise a first engaging element, and by configuring the first portion of the primary connecting element to comprise a respective second engaging element configured to be rigidly engaged with the first engaging element. Preferably, the first engaging element may be configured as a groove extending longitudinally from each respective longitudinal end of the central axis, and the second engaging element may be configured as a projection configured to be rigidly engaged with the groove.

[0031] In a preferred embodiment, the fastening element may be configured as an elongated male connector (i.e. a male fastening element) configured to be inserted through the secondary connecting element, through the primary connector element and further configured to be mechanically connected, preferably by a threaded connection, to the respective longitudinal end portion of the central axis. In this embodiment, each of the primary connecting element and the secondary connecting element may comprise a respective through hole for inserting the fastening element.

[0032] In an alternative embodiment, the fastening element may be configured as a female connector (i.e. a female fastening element) (e.g. comprising an inner threaded portion), such as a nut, configured to be connected to the respective longitudinal end portion of the central axis. Additionally, the central axis may be configured to pass through the primary connector and through the secondary connector, to be mechanically connected to the fastening element. In this embodiment, each of the primary connecting element and the secondary connecting element may comprise a respective through hole for inserting the central axis.

[0033] Each set of connecting elements of the connecting device may further comprise a respective knob element (i.e. there may be one or two knob elements). Each knob element may be configured to be rigidly connected to each fastening element (wherein each fastening element is according to any of the fastening elements previously described). Each knob element may comprise (or may be configured as) a gripping portion configured to be handled by a user to exert a force for connecting the respective fastening element to the respective longitudinal end of the central axis. The gripping portion may be configured to have a shape suitable for being handled with a human hand (e.g. circular shape, prism shape, ergonomic shape, bar-shaped) and may comprise a plurality of ribs and / or grooves for improving the grip between the gripping portion and the hand of a user.

[0034] Preferably, the knob element may be configured as a hollow body configured such that, when the respective fastening element is connected to the respective longitudinal end of the central axis, the hollow body houses at least a part of the secondary connecting element. This has the advantage of providing a cover protecting the connection between the different elements of a respective set from dust, humidity and water, thereby increasing the reliability of the overall connecting device.

[0035] In some embodiments, the knob element may comprise a mechanical connector configured to be selectively connected to the leg or to the secondary connecting element, thereby securing the knob element and the fastening element such that the fastening element is prevented from being accidentally disconnected.

[0036] The connecting device may further comprise a respective elastic element configured to interact with each fastening element such that, when the fastening element is connected to the respective longitudinal end, the respective elastic element provides a resisting force in a direction aligned with a longitudinal direction of the central axis. This resisting force is a pre-tensioning force configured to provide an axial tensioning force to the fastening element.

[0037] In some embodiments, the elastic element may be arranged to exert a force between the secondary connecting element and a part of the male fastening element (e.g. a part being distally arranged with respect to the respective longitudinal end of the central axis when the male fastening element is connected to the respective longitudinal end or to a part of the knob element.

[0038] Preferably, when the fastening element is configured as the previously described elongated male connector, the elastic element is configured as an elastic element comprising a central hole to insert the fastening element (e.g. as an helicoidal spring). The elastic element may be connected to a part of the male fastening element (e.g. a part being distally arranged with respect to the respective longitudinal end of the central axis when the male fastening element is connected to the respective longitudinal end) and / or to a part of the knob element (if there is knob element). When the fastening element is configured as a female fastening element, said fastening element may comprise an elastic element as previously described and / or said fastening element may be configured as a locknut (i.e. a self-locking nut). A locknut comprises a portion configured to deform elastically to provide a locking action when a male connector is threaded to the locknut.

[0039] According to some embodiments compatible with any of the preceding embodiments, the connecting device may comprise a first set of connecting elements and a second set of connecting elements both sets comprising being configured according to any of the preceding claims. The first set may be configured to be connected to one longitudinal end of the respective (two) longitudinal ends of the central axis, and the second set of connecting elements may be configured to be connected to the other longitudinal end of the respective (two) longitudinal ends of the central axis. Preferably, the connecting elements of the second set may be configured comprise any of the features previously described or may be configured to replicate the features of the connecting elements of the first set.

[0040] A second aspect of the invention refers to a system comprising: a treatment bed comprising a first group of legs comprising at least a first leg, each leg comprising a respective connecting zone; a base support for supporting the treatment bed, the base support comprising a first tubular element for connecting (i.e. by means of a corresponding connecting device) the first group of legs; and a first connecting device according to any of the preceding claims, wherein the first set of connecting elements is configured to be connected to a first longitudinal end of the central axis of the first connecting device to provide an articulated connection between the connecting zone of the first leg of the first group of legs and the first tubular element.

[0041] Preferably, the system may be configured such that the first group of legs may further comprise a second leg and wherein the first connecting device may further comprise a second set of connecting elements configured to be connected to a second longitudinal end of the central axis of the first connecting device to provide an articulated connection between the connecting zone of the second leg of the first group of legs and the first tubular element.

[0042] In a preferred embodiment: the treatment bed may further comprise a second group of legs comprising at least a first leg, each leg comprising a respective connecting zone; and the base support may further comprise a second tubular element for connecting (i.e. by means of a respective connecting element) the legs of the second group. In this same preferred embodiment, the system may further comprise a second connecting device according to any of embodiments previously described, wherein the first set of connecting elements may be configured to be connected to a first longitudinal end of the central axis of the second connecting device to provide an articulated connection between the connecting zone of the first leg of the second group of legs and the second tubular element.

[0043] Preferably, the second group of legs may further comprise a second leg and the second connecting device may further comprise a second set of connecting elements configured to be connected with a second longitudinal end of the central axis of the second connecting device to provide an articulated connection between the connecting zone of the second leg of the second group of legs and the second tubular element.

[0044] According to some embodiments of the second aspect of the invention, the base support may further comprise one or more pivoting arms, each pivoting arm being configured to pivot about an articulation of the base support. Each pivoting arm may be rigidly connected to at least one of the tubular elements. In other words, each tubular element may be rigidly connected to at least one of the pivoting arms. Thus, the first tubular element may be connected to a first pivoting arm. When the system comprises two tubular elements (e.g. a first and a second tubular element), then each tubular element may be connected to a respective pivoting arm (e.g. the first tubular element may be rigidly connected to a first pivoting arm, and the second tubular element may be rigidly connected to a second pivoting arm) or the two (or more) tubular element may be rigidly connected to a single pivoting arm. Thus, each tubular element may be configured to pivot relative to the respective articulation of the base support together with the respective pivoting arm to which the respective tubular element is rigidly connected.

[0045] Preferably, each of the one or more legs of the treatment bed may be configured to be solidly connected (i.e. rigidly connected) to the treatment bed of the system, e.g. such that in a position of use of the treatment bed (i.e. a substantially horizontal position) the legs are arranged in a substantially vertical disposition. Preferably, each of the one or more tubular elements of the base support are arranged horizontally and transversely with respect to the treatment bed.

[0046] In preferred configurations, at least a part of the treatment bed is configured to remain always in a horizontal position and the legs are connected to a lower part of said horizontal part of the treatment bed and are configured to be arranged vertically (i.e. to extend along a direction of elongation being vertical, this direction being perpendicular to the central axis).

[0047] A third aspect of the invention refers to a method of connection of (or method for connecting) at least one leg of a treatment bed to a tubular element of a base support (the leg and the tubular element being according to the above description) by means of a connecting device according to any of the embodiments described for the connecting device. In particular, the method comprises: inserting the central axis of the connecting device into the respective tubular element; for each set of connecting elements: connecting coaxially the first portion of the primary connecting element to an end of the tubular element such that the primary element is rotatable relative to the tubular element around a geometrical axis aligned with the central axis, wherein preferably this step further comprises rigidly engaging the first portion to the central axis; connecting by form-fitting the connecting zone of the respective leg to the second portion of the primary connecting element; connecting by form-fitting the first portion of the secondary connecting element to the second portion of the primary connecting element and / or to the connecting zone of the leg; and connecting the fastening element to the respective longitudinal end of the central axis to provide a fastening force to lock the secondary connecting element (4) to the primary connecting element.

[0048] The method of the third aspect of the invention is applicable to any configuration previously described for each configuration of the primary connecting element, the secondary connecting element, and the fastening element.BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figs. 1A-1D depict different views of a connecting device 1 according to a first embodiment of the invention assembled with two respective legs L of a treatment bed (not shown) a tubular element T of a base support (not shown). Figs. 2A and 2B show respectively a detailed view and an exploded view of a connecting device 1 according to the first embodiment of the invention as shown in Figs. 1A-1D. Figs. 3A-3D depict different views of a central axis 2 of the connecting device 1 of the first embodiment. Figs. 4A-4E depict different views of a primary connecting element 3 of a connecting device 1 according to the same first embodiment of the invention. Figs. 5A-5E show different views of a secondary connecting element 4 of a connecting device 1 according to the first embodiment of the invention. Figs. 6A-6D depict different views of a connecting device 1 according to a second embodiment of the invention assembled with two respective legs L of a treatment bed (not shown) a tubular element T of a base support (not shown). This second embodiment is compatible with any of the configuration shown in Figs. 2A-2B, 3A-3D, 4A-4E and 5A-5E. Figs. 7A-7D depict different views of a connecting device 1 according to a third embodiment of the invention assembled with two respective legs L of a treatment bed (not shown) a tubular element T of a base support (not shown). This second embodiment is compatible with any of the configuration shown in Figs. 2A-2B, 3A-3D, 4A-4E and 5A-5E. Fig. 8A-8C show different views of a leg L of a treatment bed B compatible with embodiments of the invention. Figs. 9A-9B depict two views of a system related to the second aspect of the invention. DETAILED DESCRIPTION OF THE DRAWINGS

[0050] Fig. 1A shows a general view of a connecting device 1 according to a first embodiment of the invention assembled with two respective legs L of a treatment bed (not shown) a tubular element T of a base support (not shown) to provide an articulated connection between both elements, thereby enabling a relative rotation movement between them. Figs. 1B and 1D show respectively a partially and a fully exploded view of the same first embodiment. Fig. 1C shows a section view (or cutaway view) of the same first embodiment. Figs. 2A and 2B shown more detailed views of the same first embodiment of the connecting device 1, but in this case conveniently isolated from the tubular element T and the legs L.

[0051] The connecting device 1 of the first embodiment of Figs. 1A-1D comprises a central axis 2 configured to be inserted within the tubular element T (e.g. inserted through one of the two end portions of the tubular element T), a first set G1 of connecting elements 3-5 and an optional second set G2 of connecting elements 3-5, wherein the first set G1 is configured to be connected to a first longitudinal end 20 of the central axis 2, and wherein the optional second set G2 is configured to be connected to a second longitudinal end 21 of the central axis 2 (the longitudinal end portions 20, 21 are shown in more detail in Fig. 3A, and both correspond to respective zones of the central axis located at the ends of the central axis 2).

[0052] Each set G1, G2 respectively comprises: a primary connecting element 3, a secondary connecting element 4 and a fastening element 5 (also referred to as fastening connecting element 5).

[0053] It should be noted that the second set G2 is optional, so that in some embodiments this set may be replaced by configuring the corresponding longitudinal end portion 21 (i.e. the one not being connected to the first set G1) of the central axis 2 as a contacting element configured (i.e. shaped or formed; not shown) to prevent its insertion into the tubular element T.

[0054] The configuration of the primary connecting elements 3 of the first embodiment is shown in more detail in Figs. 4A-4E. Each primary connecting element comprises a first portion 31 (i.e. a first part) and a second portion 32 (i.e. a second part). The first 31 and second portions 32 are configured as respective opposing portions (e.g. parts or faces) of the primary connecting element 3 The first 31 and the second 32 portions are solidly / rigidly connected to each other. Figs. 4A-4E depict the optional configuration in which said solid / rigid connection is achieved by configuring the primary connecting element 3 to be a monobloc element (i.e. form as a single body).

[0055] The first portion 31 is configured to be coaxially connected to an end of the tubular element T. In the first embodiment it is depicted the preferred configuration in which the first portion 31 is configured to be coaxially inserted within one of the ends of the tubular element T (the tubular element T comprises two ends). It should be noted that in other compatible embodiments, the first portion 31 may be configured to coaxially surround one of the ends of the tubular element T. This connection is further configured to allow the primary element 3 to be rotatable relative to the tubular element T around a geometrical axis aligned with the central axis 2. However, in other compatible embodiments, the first portion 31 may be configured to receive by insertion an end of the tubular element T, such that the primary element 3 is equally rotatable relative to the tubular element T. The coaxial connection may be configured to provide a sliding (also referred to as frictional) contact between a surface of the primary connecting element 3 (e.g. a surface of the first portion 31) and a surface of the tubular element (e.g. in the first embodiment this surface being an inner surface / wall of the tubular element T).

[0056] The second portion 32 of the primary connecting element 3 is configured to be connected (i.e. interlocked or engaged) by form-fitting (i.e. rigidly connected) to a connecting zone Z (shown in Fig. 8A) of a leg L of the treatment bed B. In particular, the second portion 32 of the primary connecting element 3 is configured (e.g. shaped / formed) to be connected / interlocked / engaged by form-fitting to the connecting zone Z of a respective leg L such that, when an external force (e.g. a force applied by a user) causes a relative rotation between the tubular element T and the leg about the a central geometrical axis (i.e. this axis being a spatial reference) of the central axis 2), then said form-fitting (i.e. between the second portion 32 and the connecting zone Z of the leg L) causes an identical relative rotation between the primary connecting element 3 and the tubular element T. Therefore, the form fitting connection joins together the leg L (i.e. the connecting zone Z of the leg L) and the second portion 32 of the primary connecting element 3 such that both elements are configured to be rotatable together relative to the tubular element T (further, if the tubular element T rotates a number of degrees relative to the leg L, then the tubular element T is necessarily rotated the same number of degrees relative to the primary connecting element 3). Thereby, the above referred form-fitting connection enables the tubular element T to be rotatable relative to both the primary contacting element 3 and the respective leg L.

[0057] The primary connecting element 3 of the first embodiment further comprise a spacing portion 33 (optional feature) arranged between its respective first and second portions. Preferably, the spacing portion 33 is configured (e.g. shaped and / or sized) to prevent its insertion into the tubular element T. In Figs. 4A-4E, the spacing portion 33 is configured as to have a bigger diameter than the tubular section T.

[0058] The configuration of the secondary connecting elements 4 of the first embodiment is shown in more detail in Figs. 5A-5E. Each secondary connecting element 4 of the first embodiments comprises a respective first portion 41 configured to be connected / interlocked / engaged by form-fitting (i.e. rigidly connected) to the second portion 32 of the primary connecting element 3 and to the connecting zone Z of the leg L of the treatment bed B. It should be noted that in other compatible embodiments, the first portion 41 of secondary connecting element may be alternatively configured to be connected by form-fitting to the second portion 32 of the primary connecting element 3 and / or to the connecting zone Z of the leg L of the treatment bed B.

[0059] The previously described rigid connection by form-fitting between the primary connecting element 3 and the connecting zone Z of the leg L forms a rigid group between these two elements, then the connection by form-fitting of the first portion 41 of the secondary connecting element 41 to the second portion 32 of the primary connecting element 3 and to the connecting zone Z of the leg L ensures that the secondary connecting element 4 is rigidly connected to said rigid group. Thus, the connecting device 1 provides an articulated connection that enables a relative rotation between the tubular element T and the rigidly interconnected group formed by the primary connecting element 3, the leg L and the secondary connecting element 4.

[0060] The fastening element 5 (see Figs. 1A-1D and 2A-2B) of each set G1, G2 is configured to be connected to the respective longitudinal end 20, 21 of the central axis 2. Each fastening element 5 is configured to provide a fastening force to lock the secondary connecting element 4 to (i.e. against) the primary connecting element 3, and to lock the primary connecting element 3 to the respective longitudinal end 20, 21 of the central axis 2. The fastening force is configured in this case as a compression force.

[0061] The first embodiment is further configured to comprise the optional feature in which the second portion 32 of the primary connecting element 3 configured to be rigidly connected by form-fitting to the connecting zone Z of the leg L is configured such that said form-fitting connection is achieved when the connecting zone Z of the leg L is connected to the second portion 32 in a direction perpendicular to the central axis 2 (e.g. a radial direction extending radially from or towards the central axis). In Figs. 1C and 1D it can be observed that said direction perpendicular to the central axis is also a direction being coincident with a direction of elongation of the respective leg L.

[0062] The connecting zone Z of each leg L (shown in more detail in Figs. 8A-8C) of the first embodiment is arranged at a respective end portion of the leg L and is further configured as (or comprises) an open-end portion (also referred to as receiving portion) configured to receive (e.g. to engage by form-fitting with) the second portion 32 of the primary connecting element 3. The connecting zone Z is shown as comprising at least two longitudinal projections 414 (i.e. aligned with the direction of elongation of the leg), such that the open-end portion is defined between the at least two longitudinal projections 414.

[0063] In the figures of the same embodiment, the second portion 32 of the primary connecting element 3 is shown as comprising (or as being configured as) a three-dimensional geometric solid (in other embodiments more than one three-dimensional geometric solid may be comprised by the second portion 32) extending along a longitudinal direction of the central axis 2 (i.e. a direction between the two respective longitudinal ends 20, 21 of the central axis 2). The three-dimensional geometric solid is configured to be connected by form-fitting to the connecting zone Z of the respective leg L. This configuration provides an increased contact surface between this second portion and the connecting zone of the leg and with the first portion of the secondary connecting element.

[0064] More particularly, the second portion 32 of the Figs. 4A-4E is configured (optional feature) as a three-dimensional geometric body comprising two faces (although other configurations previously described in the description are compatible): a substantially planar face and a U-shaped curved face which are connected to each other by means of two respective round edges (optional feature). However, in other embodiments, the at least one three-dimensional geometric solid may be configured as at least one elliptical cylinder and / or as at least one prism a plurality of lateral faces.

[0065] The first portion 41 of the secondary connecting element 4 of Figs. 5A-5D is shown as being configured such that its form-fitting connection to the second portion 32 of the primary connecting element 3 and to the connecting zone Z of the leg L is achieved when the secondary connecting element 4 is moved (i.e. towards the primary connecting element 3 and the connecting zone Z to be connected therein) in a direction aligned with a longitudinal direction of the central axis 2.

[0066] In the particular case of the first embodiment, the first portion 41 of the secondary connecting element 4 is shown as being configured to be connected by form-fitting to the second portion 32 of the primary connecting element 3 configured as (or comprising) the above-defined three-dimensional geometric solid. Said three-dimensional geometric solid 32 is configured (e.g. sized or dimensioned) to have a length such that a first portion of said length is configured to be in contact with the open-end portion (the receiving portion) of the connecting zone Z of the respective leg L. Further, the first embodiment is configured to have the optional feature in which the (at least one) three-dimensional geometric solid is further configured such that a second portion of said length is configured to be in contact with the first portion 41 of the secondary connecting element 4 (this can be observed in Fig. 1B, where it can be seen that the three-dimensional geometric body protrudes beyond a contact area with the connecting zone Z of the leg L.). However, when there is no optional second portion of the length, then the first portion of the length may be coincident with the length of the three-dimensional geometric solid, i.e. with the total length of the three-dimensional geometric solid.

[0067] The first portion 41 of the secondary connecting element 4 is shown in Figs. 5B-and 5C as comprising a respective locking element 411 configured to be connected to a corresponding locking element 413 (shown in Figs. 8A-and 8B) of the connecting zone Z of the respective leg L. The connection (e.g. by interlocking) between the respective locking elements 411 and 413 of the secondary connecting element 4 and of the leg L are configured to lock (upon their interconnection to each other) the connecting zone Z of the respective leg L with respect to the connecting device 1 such that the leg L is prevented from moving relative to the connecting device in a direction being perpendicular (i.e. a direction extending radially from or towards the central axis) to the central axis 2.

[0068] It should be noted that in other compatible embodiments the number locking elements 411 and 413 may be greater. In Figs. 5B and 5C the locking element 411 of the first portion 41 of the secondary connecting element 4 comprises (or is configured as) one protrusion (e.g. a pin). In other embodiments, the locking element 411 may be configured to comprise at least one projection and / or at least one recess (e.g. at least one hole) configured to be connected to the respective one or more locking elements 413 of the connecting zone Z of the leg L, which may be correspondingly configured (e.g. shaped or formed) to engage with the locking elements 411 of the first portion 41 of the secondary connecting element 4. Thus, in the case of Figs. 8A and 8B, the locking element 413 of the connecting zone Z of the leg L is configured as a respective recess, mores specifically as a respective hole. However, other configurations are compatible with the one or more locking element 413.

[0069] Figs. 8A and 8B depict the preferred and optional configuration in which the one or more locking elements 413 of the connecting zone Z of the leg L are arranged closest to the treatment bed B (in a position of use) than the rest of said connecting zone Z.

[0070] Additionally, the first portion 41 of the secondary connecting element 4 of Figs. 5A-5E comprises a plurality of projections 412 configured to provide the form-fitting connection (e.g. rigid connection) to the second portion 32 of the primary connecting element 3 and / or to the connecting zone Z of the leg of the treatment bed L. In some embodiments, the plurality of projections 412 may be replace by a single projection 412. The plurality of projections 412 of Figs. 5A-5E comprise two lateral projections configured to embrace externally the connecting zone Z of the respective leg L and a further projection 412 configured to be connected by form-fitting with the first portion 31 of the primary connecting element 3 (e.g. with the curved face of the three-dimensional geometric solid) and with the connecting zone Z of the leg (e.g. with a lower part of the connecting zone Z, such as the two longitudinal projections 414). The configuration of the projections 412 is compatible with other configurations described in the specification.

[0071] In the first embodiment of the connecting device 1, the first portion 31 of the primary connecting element 3 is optionally configured to be rigidly connected / engaged / coupled with the central axis 2 (e.g. to the respective longitudinal end of the central axis), thereby reducing internal friction in the connecting device of the invention when the tubular element is rotated. Thus, in Fig. 4C it is shown that the first portion 31 of the primary connecting element 3 is configured to be rigidly engaged with the central axis 2 of Figs. 3A-3D by configuring the central axis 2 to comprise a first engaging element 22 (e.g. a respective first engaging element 22 per longitudinal end 20, 21), and by configuring the first portion 31 of the primary connecting element 3 to comprise a respective second engaging element 34 configured to be rigidly engaged with the first engaging element 22. Figs. 3A-3D and 4C show a preferred (and optional) embodiment in which the first engaging element 22 is configured as a groove extending longitudinally from each respective longitudinal end 20, 21 of the central axis 2, and the second engaging element 34 is configured as a respective projection configured to be rigidly engaged with the groove.

[0072] Finally, in the first embodiment, the fastening element 5 of the first embodiment is shown in Figs. 1A-1D and 2A-2B as being configured as an elongated male connector configured to be inserted through the secondary connecting element 4, through the primary connector element 3 and further configured to be mechanically connected by means of a threaded connection to a respective threaded portion 23 of the respective longitudinal end portion 20, 21 of the central axis 2. In this embodiment, each of the primary connecting element 3 and the secondary connecting element 4 comprise a respective through hole for inserting the fastening element 5.

[0073] It should be noted that the configurations (and its variations according to the features described in the summary of the invention) shown for the central axis 2 in Figs. 3A-3D, for the first connecting element 3 in Figs. 4A-4E and for the secondary connecting element 4 in Figs. 5A-5E are compatible with a plurality of embodiments, not being restricted to the first embodiment of the connecting element 1.

[0074] Figs. 6A-6D depict a second embodiment of the connecting element 1 which is compatible with the primary connecting element 3 of Figs. 4A-4E, with the secondary connecting element 4 of Figs. 5A-5E and with the legs L of Figs. 8A and 8B. In this second embodiment, the fastening element 5 is configured as a female connector (e.g. as a nut; e.g. a locknut comprising a portion configured to deform elastically to provide a locking action when said portion is threaded around the respective longitudinal end 20, 21) configured to be connected to the respective longitudinal end portion 20, 21 of the central axis 2. Additionally, the central axis 2 is configured to pass through the primary connector 3 and through the secondary connector 4, to be mechanically connected (e.g. by a threaded connection) to the fastening element 5. In this embodiment, each of the primary connecting element 3 and the secondary connecting element 4 comprise a respective through hole for inserting the central axis 2. Although not depicted in the figures, in alternative embodiments, the connecting device may be configured to comprise a first fastening element (i.e. a fastening element of the first set G1) configured as a male connector and a second fastening element (i.e. a fastening element of the second set G2) configured as a female connector, thereby adapting each respective longitudinal end 20, 21 of the central axis according to the description above provided for each configuration of the fastening element 5.

[0075] Figs. 7A-7D depict a third embodiment of the connecting element 1 which is compatible with the primary connecting element 3 of Figs. 4A-4E, with the secondary connecting element 4 of Figs. 5A-5E and with the legs L of Figs. 8A and 8B. In this third embodiment, the connecting device 1 is configured as the one of the first embodiment as shown in Figs. 1A-1D, but further comprises two knob elements 51 (it should be noted that in other embodiments with only one set -e.g. a first set-of connecting elements, the connecting device 1 may comprise only one knob element 51). Each knob element 51 is configured to be rigidly connected to each fastening element 5. It should be noted that in Figs. 7A-7B the fastening elements are configured as respective male connectors, but the knob element 51 is also compatible with a fastening element 5 configured as a female connector (i.e. the knob element 51 is also compatible with being connected to a nut, so that the knob element are also compatible with the second embodiment described in Figs. 6A-6D.

[0076] Each knob element comprises (or is configured as) a gripping portion configured to be handled by a user to exert a force for connecting the respective fastening element 5 to the respective longitudinal end 20, 21 of the central axis 2. The gripping portion shown in Figs. 7A-7D is configured to have a shape suitable for being handle with a human hand and comprise a plurality of optional ribs and / or grooves for improving the grip between the gripping portion and the hand of a user.

[0077] Figs. 7A-7D shown an optional and preferred configuration in which the knob element 51 is configured as a hollow body configured such that, when the respective fastening element 5 is connected to the respective longitudinal end 20, 21, the hollow body houses at least a part of the secondary connecting element 4.

[0078] The knob element 51 shown in Figs. 7A-7D is compatible (as an optional element) with the first and the second embodiments.

[0079] Although not visible in the figures, it should be noted that the connecting device 1 of any of the embodiments shown in the figures may further comprise a respective elastic element configured to interact with each fastening element 5 such that, when the fastening element 5 is connected to the respective longitudinal end 20, 21, the respective elastic element provides a resisting force in a direction aligned with a longitudinal direction of the central axis 2. This resisting force is a pre-tensioning force configured to provide an axial tensioning force to the fastening element 5. The elastic element may be configured according to the different definitions provided in the summary of the invention.

[0080] Figs. 9A-9B depict two views of a system 100 related to the second aspect of the invention. The system 100 depicted in Figs. 9A-9B comprises: a treatment bed B comprising a first group of legs L1 comprising at least a first leg L11, each leg of the first group L1 comprising a respective connecting zone Z; a base support S for supporting the treatment bed B, the base support S comprising a first tubular element T1 for connecting (i.e. by means of a corresponding connecting device 1) the first group of legs L1; and a first connecting device 1 according to any embodiment described for the connecting device, wherein the first set G1 of connecting elements is configured to be connected to a first longitudinal end 20 of the central axis 2 of the first connecting device 1 to provide an articulated connection between the connecting zone Z of the first leg L11 of the first group of legs L1 and the first tubular element T1.

[0081] The system 100 is also configured (optional feature) such that the first group of legs L1 further comprises a second leg L12 and wherein the first connecting device 1 further comprises a second set G2 of connecting elements configured to be connected to a second longitudinal end 21 of the central axis 2 of the first connecting device 3 to provide an articulated connection between the connecting zone Z of the second leg L12 of the first group of legs L1 and the first tubular element T1.

[0082] The system 100 shown in the figures, further comprises an optional second group of legs L2 comprising at least a first leg L21, each leg of the second group L2 comprising a respective connecting zone Z; and the base support S further comprises a second tubular element T2 for connecting (i.e. by means of a respective connecting element 1') the legs of the second group L2. The system 100 further comprises an optional second connecting device 1' according to any of embodiments previously described for the connecting device, wherein the first set G1 of connecting elements is configured to be connected to a first longitudinal end 20 of the central axis 2 of the second connecting device 1' to provide an articulated connection between the connecting zone Z of the first leg L21 of the second group of legs L2 and the second tubular element T2.

[0083] The system 100 is also configured (optional feature) such that the second group of legs L2 further comprises a second leg L22 and the second connecting device 1' further comprises a second set G2 of connecting elements configured to be connected with a second longitudinal end 21 of the central axis 2 of the second connecting device 1' to provide an articulated connection between the connecting zone Z of the second leg L22 of the second group of legs L2 and the second tubular element T2.

[0084] Further, the system 100 depicted in figures 9A and 9B is configured such that the base support S further comprises two pivoting arms A1 and A2, each pivoting arm A1-A2 being configured to pivot about an articulation (e.g. the first pivoting arm A1 is configured to pivot with respect to a first articulation A11; e.g. the second pivoting arm A2 is configured to pivot with respect to a second articulation A21) of the base support S. Each pivoting arm A1-A2 is rigidly connected to one of the tubular elements T1-T2 articulation. In particular, the first tubular element T1 is connected to a first pivoting arm A1 and the second tubular element T2 is connected to a second pivoting arm A2. In alternative embodiments, the first T1 and the second T2 tubular elements may be rigidly connected to a single pivoting arm (directly or by means of an auxiliary structure).

[0085] Each of legs L11, L12, L21, L22 of the treatment bed B of the system 100 are configured to be solidly connected (i.e. rigidly connected) to the treatment bed B, e.g. such that in a position of use of the treatment bed (i.e. a substantially horizontal position) the legs are arranged in a substantially vertical disposition. However, the invention is compatible with other arrangements for the legs L11, L12, L21, L22. Each tubular element T1, T2 of the base support S of the system 100 are arranged horizontally and transversely with respect to the treatment bed B.

[0086] The system 100 depicted in the figures shows the preferred (and optional) configuration in which the system 100 is configured such that at least a part of the treatment bed B is always in a horizontal position / arrangement and the legs L11, L12, L21, L22 are connected to a lower part of said part of the treatment bed B and are preferably configured to be arranged in a substantially vertical position (i.e. to extend along a direction of elongation being vertical, this direction being perpendicular to the central axis).

[0087] Fig. 9A shows the system 100 according to the second aspect of the invention in a position of use of the treatment bed B in which the treatment bed B is arranged at a predetermined high position (i.e. with the treatment bed B being arranged at a predetermined height relative to the base support S; e.g. the predetermined high position being the highest position of the treatment bed B). Fig. 9B shows the same system 100 of Fig. 9A but with the treatment bed B being arranged at a predetermined low position (i.e. with the treatment bed B being arranged at a predetermined height relative to the base support S, this predetermined height being lower than that of the high position; e.g. the predetermined low position being the lowest position of the treatment bed B).

[0088] Accordingly, for each connecting device 1 and 1' (it should be noted that each may comprise a respective central axis 2 and at least a first set G1 comprising a primary connecting element 3, a secondary connecting element 4 and a fastening element 5), as the respective second portion 32 of the primary connecting 3 element is configured (e.g. shaped / formed) to be connected / interlocked / engaged by form-fitting to the connecting zone Z of a respective leg of the respective group of legs, then, when a user (e.g. a therapist or a member of a medical staff) provides an external force to move the treatment bed B between two positions (e.g. from the position shown in Fig. 9A to the position shown in Fig. 8B or vice versa), this force causes a relative rotation between the respective tubular element T1 / T2 and the respective leg (e.g. the L11, L12, L21, L22) about the respective central axis 2 (or about the central geometrical axis of the respective central axis 2) so that said form-fitting (i.e. between the second portion 32 and the connecting zone Z of the respective leg) causes an identical relative rotation between the primary connecting element 3 and the respective tubular element T1 / T2 (i.e. with respect to the first tubular element T1 for the first connecting device 1; i.e. with respect to the first tubular element T2 for the second connecting device 1'). Therefore, the form fitting connection joins together the respective leg L11, L12, L21, L22 (i.e. the respective connecting zone Z) and the second portion 32 of the primary connecting element 3 such that both elements are configured to be rotatable together relative to the respective tubular element T.

[0089] The configuration of the system 100 shown in Figs. 9A and 9B is particularly advantageous because it provides a quick connection solution (i.e. by means of one or more connecting devices 1 / 1' according to the first aspect of the invention) between the treatment bed B and the base support S, while said quick connection solution further provides the possibility of adjusting the height of the treatment bed B relative to the base support with a reduced effort.

Claims

1. A connecting device (1) for articulated connection between one or more legs (L) of a treatment bed (B) and a tubular element (T) of a base support (S) of the treatment bed (B), the connecting device (1) comprising: a central axis (2) configured to be arranged within the tubular element (T) of the base support (S), the central axis (2) comprising two respective longitudinal ends (20, 21); and at least a first set (G1, G2) of connecting elements (3, 4, 5), wherein each set (G1, G2) is configured to be connected to one of the respective longitudinal ends (20, 21) of the central axis (2), wherein each set (G1, G2) of connecting elements (3, 4, 5) comprises: a primary connecting element (3) comprising a first portion (31) and a second portion (32), wherein the first portion (31) is configured to be coaxially connected to an end of the tubular element (T) such that the primary element (3) is rotatable relative to the tubular element (T) around a geometrical axis aligned with the central axis (2), wherein the second portion (32) is configured to be rigidly connected by form-fitting to a connecting zone (Z) of the leg (L) such that, when an external force causes a relative rotation between the tubular element (T) and the leg (L) about the geometrical axis aligned with the central axis (2), then said form-fitting between the second portion (32) and the connecting zone (Z) of the leg (L) causes an identical relative rotation between the primary connecting element (3) and the tubular element (T); a secondary connecting element (4) comprising a first portion (41) configured to be rigidly connected by form-fitting to the second portion (32) of the primary connecting element (3) and / or to the connecting zone (Z) of the leg (L) of the treatment bed (B); and a fastening element (5) configured to be connected to the respective longitudinal end (20, 21) of the central axis (2) and further configured to provide a fastening force to lock the secondary connecting element (4) to the primary connecting element (3).

2. The connecting device (1) of claim 1, wherein the primary connecting element (3) further comprises a spacing portion (33) arranged between the first portion (31) and the second portion (32), wherein preferably the spacing portion (33) is configured to prevent its insertion into the tubular element (T) and / or to prevent a contact between the leg (L) and the tubular element (T).

3. The connecting device (1) of claims 1 or 2, wherein the second portion (32) of the primary connecting element (3) configured to be rigidly connected by form-fitting to the connecting zone (Z) of the leg (L) of the treatment bed (B) is configured such that said form-fitting connection is achieved when the connecting zone (Z) of the leg (L) is connected to the second portion (32) in a direction at least partially perpendicular to the central axis (2).

4. The connecting device (1) of any of the preceding claims, wherein the second portion (32) of the primary connecting element (3) is configured as at least one three-dimensional geometric solid extending along a longitudinal direction of the central axis (2) and comprising one or more lateral faces, wherein preferably said at least one three-dimensional geometric solid is configured to be arranged centrally with respect to the central axis (2).

5. The connecting device (1) of claim 4, wherein at least one of the lateral faces of the at least one three-dimensional geometric solid is configured as a curved face and / or wherein at least two of the one or more faces of the prism are separated by means of a rounded edge.

6. The connecting device (1) of any of the preceding claims, wherein the first portion (41) of the secondary connecting element (4) is further configured such that its form-fitting connection to the second portion (32) of the primary connecting element (3) and / or to the connecting zone (Z) of the leg (L) is achieved when the secondary connecting element (4) is moved in a direction aligned with a longitudinal direction of the central axis (2).

7. The connecting device (1) of any of the preceding claims, wherein the first portion (41) of the secondary connecting element (4) comprises one or more locking elements (411) configured to be connected to corresponding one or more locking elements (413) of the connecting zone (Z) of the leg (L) to lock the leg (L) with respect to the connecting device (1) such that the leg (L) is prevented from moving relative to the connecting device (1) in a direction being perpendicular to the central axis (2); wherein preferably the one or more locking elements (411) of the first portion (41) of the secondary connecting element (4) comprise at least one protrusion and / or at least one recess, such as a hole, configured to be connected to the respective one or more locking elements of the connecting zone (Z) of the leg (L).

8. The connecting device (1) of any of the preceding claims, wherein the first portion (41) of the secondary connecting element (4) comprises one or more projections (412) configured to provide the form-fitting connection to the second portion (32) of the primary connecting element (3) and / or to the connecting zone (Z) of the leg (L) of the treatment bed (B); wherein preferably said one or more projections (412) are configured to embrace the second portion (32) of the primary connecting element (3) and / or to embrace the connecting zone (Z) of the leg (L) of the treatment bed (T).

9. The connecting device (1) of any of the preceding claims, wherein the first portion (31) of the primary connecting element (3) is configured to be rigidly engaged with the central axis (2); wherein preferably the first portion (31) of the primary connecting element (3) is configured to be rigidly engaged with the central axis (2) by configuring the central axis (2) to comprise a first engaging element (22), and by configuring the first portion (31) of the primary connecting element (3) to comprise a respective second engaging element (34) configured to be rigidly engaged with the first engaging element (22); wherein more preferably the first engaging element (22) is configured as a groove (22) extending longitudinally from each respective longitudinal end (20, 21) of the central axis, and wherein the second engaging element (34) is configured as a projection configured to be rigidly engaged with the groove (22).

10. The connecting device (1) of any of the preceding claims, wherein either: the fastening element (5) is configured as an elongated male connector configured to be inserted through the secondary connecting element (4), through the primary connecting element (3) and further configured to be mechanically connected, preferably by a threaded connection, to the respective longitudinal end portion (20, 21) of the central axis (2); or the fastening element (5) is configured as a female connector, such as a nut, configured to be connected to the respective longitudinal end portion (20, 21) of the central axis (2), wherein the central axis (2) is configured to pass through the primary connecting element (3) and through the secondary connecting element (4), to be mechanically connected to the fastening element (5).

11. The connecting device (1) of any of the preceding claims, further comprising a respective knob element (51) rigidly connected to each fastening element (5), said knob element (51) comprising a gripping portion configured to be handled by a user to exert a force for connecting the respective fastening element (5) to the respective longitudinal end (20, 21) of the central axis (2); wherein preferably the knob element (51) is configured as a hollow body configured such that, when the respective fastening element (5) is connected to the respective longitudinal end (20, 21), the hollow body houses at least a part of the secondary connecting element (4).

12. The connecting device (1) of any of the preceding claims, further comprising a respective elastic element configured to interact with each fastening element (5) such that, when the fastening element (5) is connected to the respective longitudinal end (20, 21), the respective elastic element provides a resisting force in a direction aligned with a longitudinal direction of the central axis (2); wherein preferably, when the fastening element (5) is configured as the elongated male connector of claim 10, the elastic element is configured as an elastic element comprising a central hole to insert the fastening element (5), wherein more preferably said elastic element is configured as an helicoidal spring.

13. The connecting device (1) of any of the preceding claims, wherein the first set (G1) of connecting elements (3, 4, 5) is configured to be connected to one longitudinal end (20) of the respective longitudinal ends (20, 21) of the central axis (2), and wherein the connecting device (1) further comprises a second set (G2) of connecting elements (3, 4, 5) configured to be connected to the other longitudinal end (21) of the respective longitudinal ends (20, 21) of the central axis (2), wherein preferably the connecting elements (3, 4, 5) of the second set (G2) are configured according to any of the preceding claims or are configured to replicate the features of the connecting elements (3, 4, 5) of the first set (G1).

14. A system (100) comprising: a treatment bed (B) comprising a first group (L1) of legs (L11, L12) comprising at least a first leg (L11), each leg (L11, L12) comprising a respective connecting zone (Z); a base support (S) for supporting the treatment bed (B), the base support (S) comprising a first tubular element (T1) for connecting the first group (L1) of legs (L11, L12); and a first connecting device (1) according to any of the preceding claims, wherein the first set (G1) of connecting elements (3, 4, 5) is configured to be connected to a first longitudinal end (20) of the central axis (2) of the first connecting device (1) to provide an articulated connection between the connecting zone (Z) of the first leg (L11) of the first group (L1) of legs (L11, L12) and the first tubular element (T1); wherein preferably the first group (L1) of legs (L11, L12) further comprises a second leg (L12) and wherein the first connecting device (1) further comprises a second set (G2) of connecting elements (3, 4, 5) configured to be connected to a second longitudinal end (21) of the central axis (2) of the first connecting device (1) to provide an articulated connection between the connecting zone (Z) of the second leg (L12) of the first group (L1) of legs (L11, L12) and the first tubular element (T1).

15. The system (100) of claim 14, wherein: the treatment bed (B) further comprises a second group (L2) of legs (L21, L22) comprising at least a first leg (L21), each leg (L21, L22) comprising a respective connecting zone (Z); the base support (S) further comprises a second tubular element (T2) for connecting the legs (L21, L22) of the second group (L2); and wherein the system further comprises: a second connecting device (1') according to any of claims 1 to 11, wherein the first set (G1) of connecting elements (3, 4, 5) is configured to be connected to a first longitudinal end (20) of the central axis (2) of the second connecting device (1') to provide an articulated connection between the connecting zone (Z) of the first leg (L21) of the second group (L2) of legs (L21, L22) and the second tubular element (T2); wherein preferably the second group (L2) of legs (L21, L22) further comprises a second leg (L22) and the second connecting device (1') further comprises a second set (G2) of connecting elements (3, 4, 5) configured to be connected with a second longitudinal end (21) of the central axis (2) of the second connecting device (1') to provide an articulated connection between the connecting zone (Z) of the second leg (L22) of the second group (L2) of legs (L21, L22) and the second tubular element (T2).

16. The system (100) of claim 14 or 15, wherein the base support (S) further comprises one or more pivoting arms (A1, A2), each pivoting arm (A1, A2) being configured to pivot about a respective articulation of the base support (S), wherein each tubular element (T1, T2) is rigidly connected to at least one of the pivoting arms (A1, A2), such that the each tubular element is configured to pivot relative to the respective articulation of the base support (S) together with the pivoting arm (A1, A2) to which it is rigidly connected.

17. A method of connection of at least one leg (L, L11, L12, L21, L22) of a treatment bed (B) to a tubular element (T1, T2) of a base support (S) by means of a connecting device (1) of any of claims 1 to 13, the method comprising: inserting the central axis (2) of the connecting device (1) into the respective tubular element (T1, T2); for each set (G1, G2) of connecting elements (3, 4, 5): connecting coaxially the first portion (31) of the primary connecting element (3) to an end of the tubular element (T) such that the primary element (3) is rotatable relative to the tubular element (T) around a geometrical axis aligned with the central axis (2), wherein preferably this step further comprises rigidly engaging the first portion (31) to the central axis (2); connecting by form-fitting the connecting zone (Z) of the respective leg (L, L11, L12, L21, L22) to the second portion (32) of the primary connecting element (3); connecting by form-fitting the first portion (41) of the secondary connecting element (4) to the second portion (32) of the primary connecting element (3) and / or to the connecting zone (Z) of the leg (L); and connecting the fastening element (5) to the respective longitudinal end (20, 21) of the central axis (2) to provide a fastening force to lock the secondary connecting element (4) to the primary connecting element (3).