Puzzle cube with internal secret compartment

Abstract

A puzzle cube includes a core, to which a plurality of central and peripheral cubies are movably associated. The core has two hemispherical shells, of which a first one is associated with a first portion of the central and peripheral cubies, and a second one is associated with a second portion, complementary to the first portion, of the central and peripheral cubies. In a closed configuration, the puzzle cube is assembled, and the two hemispherical shells are coupled and define a closed cavity therebetween. In an open configuration, the puzzle cube is divided into two complementary parts, the two hemispherical shells are separated, and the cavity is open and accessible by a user. The transition from the closed configuration to the open configuration occurs upon the simultaneous pressing of all the central cubies by the user, only when the puzzle cube is solved according to a single predetermined combination.

Claims

1. A puzzle cube comprising: a core; and a plurality of central cubies and a plurality of peripheral cubies movably associated to the core, wherein: the core is defined by two hemispherical shells, of which a first hemispherical shell is associated with a first part of the central cubies and of the peripheral cubies, and a second hemispherical shell is associated with a second part of the central cubies and of the peripheral cubies, complementary to the first part; the puzzle cube has a closed configuration in which: the puzzle cube is assembled, the two hemispherical shells are mutually coupled to each other, and the two hemispherical shells define a closed cavity between them, and and an open configuration in which: the puzzle cube is divided into two complementary parts, the two hemispherical shells are separated from each other, and the cavity is open and accessible by a user; a transition from the closed configuration to the open configuration occurs upon a simultaneous pressing of all the central cubies by a user; each of the peripheral cubies comprises a respective flange facing the core; and each flange of each of the peripheral cubies comprises at least one coded element having a shape selected from a plurality of different shapes; further comprising a plurality of complementary coded elements having a shape selected from a plurality of shapes complementary to the shapes of the coded elements of the peripheral cubies, wherein a pressing of the central cubies to achieve the transition from the closed configuration to the open configuration of the puzzle cube is permitted only when the coded elements of all the peripheral cubies are aligned with corresponding complementary coded elements of the puzzle cube that have the shape complementary to the shape of the corresponding coded elements.

2. The puzzle cube according to claim 1, wherein the coded elements are aligned with the corresponding complementary coded elements only when the puzzle cube is solved according to a single predetermined combination.

3. The puzzle cube according to claim 1, wherein each of the hemispherical shells comprises: a reciprocal engagement element for engaging with the other hemispherical shell, and a lever for each of the central cubies, wherein the central cubies comprise a central column adapted to actuate a first end of the lever, and wherein a second end of the lever, opposite to the first end, is configured to engage and disengage from the reciprocal engagement element depending on whether the central column actuates the first end of the lever, to maintain or release a reciprocal engagement of the hemispherical shells.

4. The puzzle cube according to claim 3, wherein the reciprocal engagement element of each hemispherical shell is defined by an engagement ring configured to engage the other hemispherical shell, the engagement rings being adapted to rotate around a base circumference of a respective hemispherical shell to engage with, or disengage from, one or more hooks protruding from the other hemispherical shell, respectively maintaining the two hemispherical shells in contact with each other or allowing a separation thereof, a rotation of the engagement rings to engage or disengage with the one or more hooks being permitted only upon a simultaneous pressing of all the central cubies by the user.

5. The puzzle cube according to claim 4, wherein the second end of the lever, opposite to the first end, is configured to engage in, and disengage from, a recess formed in the engagement ring depending on whether the central column actuates the first end of the lever or not.

6. The puzzle cube according to claim 4, wherein the engagement ring of one of the hemispherical shells comprises a guide for each of the hooks of the other hemispherical shell, a sliding of the hooks within the guides imposing the rotation of the engagement rings around the base circumference of the respective hemispherical shell.

7. The puzzle cube according to claim 1, wherein each of the central cubies is formed by two structures comprising an inner structure and an outer structure, the inner structure being movable axially, radially with respect to the core, within the outer structure, in a direction of approach and separation relative to the core.

8. The puzzle cube according to claim 1, wherein facets of the peripheral cubies are removable and repositionable at will.

9. The puzzle cube according to claim 1, wherein each flange of each of the peripheral cubies comprises at least one through-hole shaped according to a shape selected from a plurality of different shapes, the at least one through hole constituting the coded element, wherein each of the central cubies comprises a plurality of pins, wherein the pins associated with each central cubie are shaped according to a shape selected from a plurality of shapes complementary to the shapes of the through-holes of the peripheral cubies, the pins constituting the complementary coded elements, and wherein the pressing of the central cubies to achieve the transition from the closed configuration to the open configuration of the puzzle cube is permitted only when the through-holes of all the peripheral cubies are aligned with the pins of the central cubies, which have the shape complementary to the shape of the corresponding through-holes.

10. The puzzle cube according to claim 1, wherein each flange of each of the peripheral cubies comprises at least one through-hole, within which a shaped pin is housed, the shaped pin having an end shaped according to a shape selected from a plurality of different shapes, the shaped pin constituting the coded element, wherein each of the central cubies comprises a plurality of pins, wherein the core comprises a plurality of holes shaped according to a shape selected from a plurality of different shapes, the holes constituting the complementary coded elements, and wherein the pressing of the central cubies to achieve the transition from the closed configuration to the open configuration of the puzzle cube is permitted only when the pins of all of the central cubies are aligned with corresponding shaped pins of the flanges of the peripheral cubies and all of the shaped pins are aligned with all of the holes of the core that have the shape complementary to the shape of the corresponding shaped pins.

11. The puzzle cube according to claim 4, wherein the central cubies comprise a central column, and wherein the engagement ring comprises at least one hook-shaped protrusion configured to directly engage with, and disengage from, the central column.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Further features and advantages will become more apparent from the following illustrative, but non-limiting, description of a preferred embodiment of the present invention, illustrated with the aid of the accompanying drawings, in which:

[0013] FIG. 1 is a perspective view of an embodiment of a puzzle cube according to the invention, in the assembled configuration;

[0014] FIGS. 2a and 2b are two different perspective views of the puzzle cube of FIG. 1, in the disassembled configuration, i.e., separated into two complementary parts;

[0015] FIG. 3 is a perspective view illustrating in particular the core of the puzzle cube, in the disassembled configuration;

[0016] FIGS. 4, 5, and 6 are different perspective views of one of the two complementary parts of the puzzle cube according to the invention, with FIGS. 4 and 5 being sectional views;

[0017] FIGS. 7 and 8 are two sectional views of the puzzle cube of FIG. 1, in two different planes;

[0018] FIG. 9 shows a component of a central cubie of the puzzle cube according to the invention;

[0019] FIG. 10 shows the edge cubies of the puzzle cube according to the invention;

[0020] FIGS. 11a and 11b are sectional views of a part of the puzzle cube according to the invention, in two different usage configurations;

[0021] FIGS. 12 and 13 illustrate perspective views of some components of the puzzle cube according to the invention;

[0022] FIG. 14 illustrates a component of the puzzle cube, referred to as an engagement ring;

[0023] FIG. 15 illustrates, in a perspective view, the core of the puzzle cube according to the invention, in the assembled configuration, while FIG. 16 illustrates only a part thereof;

[0024] FIGS. 17 and 18 are enlarged perspective views of some details of the puzzle cube according to the invention;

[0025] FIG. 19 is a sectional view of a variant of the puzzle cube according to the invention;

[0026] FIGS. 20a, 20b, and 20c illustrate a variant of the fastening system between the two complementary parts of the cube according to the invention, in three different stages;

[0027] FIGS. 21a and 21b illustrate a further variant of the fastening system between the two complementary parts of the cube according to the invention, in two different stages.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0028] With particular reference to the figures, the puzzle cube, generally indicated by reference numeral 100, comprises a core 1 to which a plurality of central cubies 3 and a plurality of peripheral cubies 5, 7 are movably associated, said peripheral cubies surrounding a respective central cubie 3.

[0029] The peripheral cubies 5, 7 comprise edge cubies 5 and corner cubies 7.

[0030] Each of the central cubies 3 comprises one visible facet 30, each of the edge cubies 5 comprises two visible facets 50, 50x, and each of the corner cubies 7 comprises three visible facets 70, 70x, 70y.

[0031] The term visiblemeans that the facets are visible and accessible to a player.

[0032] The central cubies 3, edge cubies 5, and corner cubies 7 form the six faces 60 of the cube.

[0033] In particular, in the case of a 333 cube, there are six central cubies 3, twelve edge cubies 5, and eight corner cubies 7.

[0034] It should be noted that four facets 50, 50x of the edge cubies, four facets of the corner cubies 70, 70x, 70y, and one facet 30 of the central cubie define one face 60 of the puzzle cube 100. In other words, each face 60 of the puzzle cube 100 is defined by nine facets 30, 50, 50x, 70, 70x, 70y.

[0035] According to the known operation of the puzzle cube 100, each edge cubie 5 can be selectively rotated together with one of the two central cubies 3 whose facet 30 is coplanar with one of the two facets 50, 50x of the edge cubie 5, and each corner cubie 7 can be selectively rotated together with one of the three central cubies 3 whose facet 30 is coplanar with one of the three facets 70, 70x, 70y of the corner cubie 7.

[0036] According to the invention, the core 1 is defined by two hemispherical shells 1a, 1b.

[0037] A first hemispherical shell 1a is associated with a first portion of the central cubies 3 and the peripheral cubies 5, 7 (for example, a first half of the central cubies 3 and the peripheral cubies 5, 7).

[0038] A second hemispherical shell 1b is associated with a second portion, complementary to said first portion, of the central cubies 3 and the peripheral cubies 5, 7 (for example, a second half of the central cubies 3 and the peripheral cubies 5, 7 which, together with the first half, completes the cube 100).

[0039] The puzzle cube 100 has a closed configuration and an open configuration.

[0040] In the closed configuration, illustrated for example in FIG. 1, the cube 100 is assembled and the hemispherical shells 1a, 1b are mutually coupled to each other, thereby defining a closed cavity 2 between them.

[0041] In the open configuration, illustrated for example in FIGS. 2a, 2b, and 3, the cube 100 is separated into two complementary parts and the two hemispherical shells 1a, 1b, along with their respective cubies 3, 5, 7, are separated from each other, thus rendering the cavity 2 open and accessible by a user.

[0042] The transition from the closed configuration to the open configuration occurs upon the simultaneous pressing of all central cubies 3 by the user.

[0043] Each of the peripheral cubies 5, 7 comprises a respective flange 51, 71 facing the core 1.

[0044] Each flange 51, 71 of each of the peripheral cubies 5, 7 comprises at least one coded element , shaped according to a shape selected from a plurality of different shapes, here defined as a, b, c, d, e, and f.

[0045] The puzzle cube 100 further comprises a plurality of complementary coded elements C2 shaped according to a shape selected from a plurality of shapes (a, b, c, d, e, f) that are complementary to the shapes (a, b, c, d, e, f) of the coded elements C1 of the peripheral cubies 5, 7.

[0046] Pressing the central cubies 3 to achieve the transition from the closed configuration to the open configuration of the puzzle cube 100 is only allowed when the coded elements C1 of all the peripheral cubies 5, 7 are aligned with corresponding complementary coded elements C2 of the puzzle cube 100 having a shape (a, b, c, d, e, f) complementary to the shape (a, b, c, d, e, f) of the respective coded elements C1.

[0047] Preferably, the coded elements C1 of all the peripheral cubies 5, 7 are aligned with the corresponding complementary coded elements C2 of the puzzle cube 100 only when the puzzle cube 100 is solved according to a single predetermined combination.

[0048] In essence, the puzzle cube 100 can be opened-i.e., separated into its two halves only when it is solved according to a single predetermined combination. Indeed, only when the cube is solved according to said single predetermined combination are the coded elements C1 and the complementary coded elements C2 aligned with each other, thereby allowing all the central cubies 3 to be pressed simultaneously, releasing the two hemispherical shells 1a, 1b from their mutual engagement and enabling access to the internal cavity 2 of the core 1 of the puzzle cube 100.

[0049] Preferably, each hemispherical shell 1a, 1b comprises:

[0050] at least one reciprocal engagement element for engaging with the other hemispherical shell 1b, 1a;

[0051] at least one lever 31 for each of the central cubies 3.

[0052] Additionally, each central cubie 3 comprises a central column 38 adapted to actuate a first end 31 of the lever 31. A second end 31 of the lever 31, opposite the first end 31, is configured to engage with and disengage from said engagement element, depending on whether the central column 38 actuates the first end 31 of the lever 31, in order to maintain or release the mutual engagement of the hemispherical shells 1a, 1b.

[0053] Preferably, the reciprocal engagement element of each hemispherical shell 1a, 1b is defined by an engagement ring 4a, 4b for engaging with the other hemispherical shell 1b, 1a.

[0054] The engagement rings 4a, 4b are adapted to rotate around the base circumference of the respective hemispherical shell 1a, 1b in order to engage with or disengage from one or more hooks 6a, 6b protruding from the other hemispherical shell 1a, 1b, thereby either keeping the hemispherical shells 1a, 1b in contact with each other or allowing their separation.

[0055] Rotation of the engagement rings 4a, 4b to engage or disengage with said one or more hooks 6a, 6b is permitted only upon the simultaneous pressing of all the central cubies 3 by the user.

[0056] In a variant of the cube 1, illustrated in FIGS. 20a to 20c, the reciprocal engagement element of each hemispherical shell 1a, 1b is defined by a hook 60a, 60b. The second end 31 of the lever 31, opposite the first end 31, is configured to engage with and disengage from said hook 60a, 60b depending on whether the central column 38 actuates the first end 31 of the lever 31, in order to maintain or release the mutual engagement of the hemispherical shells 1a, 1b.

[0057] In this case, the second end 31 of the lever 31 is shaped as a hook 31a, 31b complementary to the respective hook 60b, 60a located on the opposite hemispherical shell 1b, 1a.

[0058] Preferably, the engagement ring 4a, 4b of a hemispherical shell 1a, 1b comprises a guide 33a for each of the hooks 6a, 6b of the other hemispherical shell 1b, 1a.

[0059] The sliding of the hooks 6a, 6b within said guides 33a imposes the above-described rotation of the engagement rings 4a, 4b around the base circumference of the respective hemispherical shell 1a, 1b.

[0060] As will be explained in greater detail below, when the two hemispherical shells 1a, 1b are released from engagement and the central cubies 3 are pressed while the user proceeds to separate the two halves of the puzzle cube 100, the separating movement of the two hemispherical shells 1a, 1b causes the respective hooks 6a, 6b to slide along the aforementioned guides 33a, whichbeing inclined with respect to the direction of separation between the two halves of the cube 100induces a rotation of the engagement rings 4a, 4b.

[0061] Preferably, as illustrated in particular in FIG. 14, the engagement rings 4a, 4b comprise one or more circumferential guides 41 that interact with corresponding sliders 42 provided on the inner surface of the hemispherical shells 1a, 1b, so that the engagement rings 4a, 4b can rotate around the base circumference of the respective hemispherical shells 1a, 1b without detaching from them.

[0062] According to a further variant of the cube 1 illustrated in FIGS. 21a and 21b, the engagement rings 4a, 4b include at least one hook-shaped protrusion 8a configured to directly engage with and disengage from the central column 38 of the central cubies 3, without the intermediation of the lever 31. Preferably, this hook-shaped protrusion 8a extends radially inward from the engagement ring 4a, facing a corresponding central column 38 of a central cubie 3. Specifically, as long as the central column 38 is not pressed by the user, the rotation of the engagement ring 4a, 4b is prevented, and the two hemispherical shells 1a, 1b remain connected to each other (see FIG. 21a). When the central columns 38 can be pressed, the engagement rings 4a, 4b are allowed to rotate, thereby enabling the sliding of the respective hooks 6a, 6b along the guides 33a provided in the opposite hemispherical shell 1a, 1b, and thus allowing the separation of the two complementary parts of the cube 1.

[0063] In essence, although the preferred embodiment of the cube includes both the levers 31 and the engagement rings 4a, 4b, the cube 1 can be implemented in variants in which either the lever 31 or the engagement rings 4a, 4b are omitted.

[0064] Preferably, each of the central cubies 3 is composed of two structures 34, 35, wherein an inner structure 34 is axially movablethat is, radially with respect to the core 1within an outer structure 35, in a direction toward and away from the core 1. The movement of the inner structure 34 relative to the outer structure 35 is evident from the comparison of FIGS. 11a and 11b.

[0065] Preferably, the facets 50, 50x, 70, 70x, 70y of the peripheral cubies 5, 7 are removable and repositionable at will. Preferably, the facets 50, 50x, 70, 70x, 70y comprise snap-fit or interlocking fastening means 58, 78 inside the peripheral cubies 5, 7. In this way, as will be explained in greater detail later, the user can move the facets 50, 70 to vary the combinationthat is, the arrangement of the facets of the peripheral cubies 50, 70 within the puzzle cube 100that enables opening of the puzzle cube 100 and access to the internal and secret cavity 2.

[0066] In the version of puzzle cube 100 illustrated in FIGS. 1 to 18, each flange 51, 71 of each peripheral cubie 5, 7 comprises at least one through-hole 52, 72 shaped according to a shape selected from a plurality of different shapes (a, b, c, d, e, f). Said at least one through hole 52, 72 constitutes the above-mentioned coded element C1. Furthermore, each of the central cubies 3 comprises a plurality of pins 32, wherein the pins associated with each central cubie 3 are shaped according to a shape selected from a plurality of shapes (a, b, c, d, e, f) complementary to the shapes (a, b, c, d, e, f) of the through holes 52, 72 of the peripheral cubies 5, 7. These pins 32 constitute the above-mentioned complementary coded elements C2.

[0067] Pressing the central cubies 3 to achieve the transition from the closed configuration to the open configuration of the puzzle cube 100 is only allowed when the through holes 52, 72 of all the peripheral cubies 5, 7 are aligned with the pins 32 of the central cubies 3, which have a shape (a, b, c, d, e, f) complementary to the shape (a, b, c, d, e, f) of the corresponding through holes 52, 72.

[0068] The coded elements C1, C2 are therefore constituted, respectively, by the shaped holes 52, 72 provided on the flanges 51, 71 of the peripheral cubies 5, 7, and by the shaped pins 32 provided in the central cubies 3.

[0069] Preferably, the shaped pins 32 are formed on the inner structure 34 of the respective central cubie 3.

[0070] In the variant of the puzzle cube 100 illustrated in FIG. 19, each flange 71 of each of the peripheral cubies 7 comprises at least one through hole 72, within which a shaped pin 172 is housed. Said shaped pin 172 has an end 172 shaped according to a shape selected from a plurality of different shapes (a, b, c, d, e, f). This shaped pin 172 constitutes the coded element C1.

[0071] Furthermore, each of the central cubies 3 comprises a plurality of pins 32, preferably formed in the inner structure 34 of the central cubie 3. Unlike the previous embodiment, however, the pins 32 have a cylindrical shape. Specifically, they do not have a particularly defined shaped profile.

[0072] The core 1 comprises a plurality of holes 12 shaped according to a shape selected from a plurality of different shapes (a, b, c, d, e, f). These holes 12 constitute the complementary coded elements C2.

[0073] Consistently with the previous embodiment, pressing the central cubies 3 to achieve the transition from the closed configuration to the open configuration of the puzzle cube 100 is permitted only when the pins 32 of all the central cubies 3 are aligned with the corresponding shaped pins 172 located in the flanges 71 of the peripheral cubies 7, and all said shaped pins 172 are aligned with all the shaped holes 12 of the core 1, which have a shape (a, b, c, d, e, f) complementary to the shape (a, b, c, d, e, f) of the corresponding shaped pins 172.

[0074] In essence, according to this variant, the coding that enables the opening of the puzzle cube 100 is not defined by a shape-coupling between the pins 32 located in the central cubies 3 and the through holes 52, 72 located in the flanges 51, 71 of the peripheral cubies 5, 7, but rather by a shape-coupling between the pins 172 sliding within through holes 72 formed in the flanges 71 of the peripheral cubies 5, 7 and holes 12 formed in the core 1.

[0075] This variant, although slightly more complex to manufacture, prevents the userespecially when the puzzle cube 100 is in the closed configurationfrom glimpsing the shape of the pins, thus avoiding the possibility of solving the puzzle cube 100 by distinguishing the different shapes of the holes 52, 72, which could otherwise be done in the first embodiment, for example by forcing a minimal separation between cubies allowed by mechanical tolerances.

[0076] The operation of the puzzle cube 100 is described below with particular reference to the figures, which illustrate a puzzle cube 100 of the 333 type.

[0077] To allow the puzzle cube 100 to open, the user must press all the central cubies 3 simultaneously. As shown in particular in FIG. 9, each central cubie 3 comprises eight pins 32, which must pass through the flanges 51, 71 of the peripheral cubies 5, 7 that, in the solved state required to open the puzzle cube 100, must surround the corresponding central cubie 3.

[0078] Just as each central cubie 3 has its own color, each central cubie 3 also has its own code, meaning it comprises its own complementary coded elements C2. In particular, each central cubie 3 is provided with pins 32 that have a predefined shape (shape a in the example of FIG. 9), which can enter only the holes 52, 72 formed in the flanges 51, 71 of the peripheral cubies 5, 7 that have a corresponding matching shape.

[0079] For example, if a red-colored peripheral cubie 5, 7 is located near a white-colored central cubie 3, the underlying flange 51, 71 may have a hole, but with a different shape (i.e., a different code), and therefore the pin 32 of the central cubie 3 will not be able to pass through it, preventing the central cubie 3 from being pressed.

[0080] As shown in FIG. 10, the six edge peripheral cubies 5 each have, in their respective flange 51, a through hole 52, each with a different shape (a, b, c, d, e, f).

[0081] Once all the central cubies 3 can be pressed simultaneously-meaning the puzzle cube 100 is solved in the combination that enables its opening-the second part of the opening mechanism is activated, allowing the cube 100 to be separated into two halves.

[0082] When the facet 30 of a central cubie 3 is pressed-against springs not shown in the figures, which keep the facet 30 in an extended position-the column 38 connected to the facet 30 is pushed inward into the cube 100, thereby actuating the first end 31 of the lever 31 associated with the respective central cubie 3.

[0083] The opposite end 31 of the lever 31, before being actuated, engages in a recess 33 formed in the engagement ring 4a, 4b. The engagement ring 4a, 4b substantially corresponds to a maximum circumference of the spherical core 1 of the cube 100, said circumference lying perpendicular to the spatial diagonal of the cube 100, that is, the diagonal connecting two exactly opposite vertices of the cube 100.

[0084] The cube 100 is in fact composed of two halves, essentially separated by a plane perpendicular to a spatial diagonal, such that each of the two halves contains three central cubies 3 arranged symmetrically around said spatial diagonal, as illustrated for example in FIG. 3.

[0085] Each of the two halves of the cube 100, and in particular each of the two hemispherical shells 1a, 1b into which the core 1 is divided, is providednear the dividing plane (the so-called equator)with the aforementioned engagement ring 4a, 4b, which is configured to rotate about the axis defined by the spatial diagonal. However, as long as even one of the three levers 31 has not been actuated, the recess 33 in the corresponding engagement ring 4a, 4b is not released, and thus the rotation of the engagement ring 4a, 4b is prevented.

[0086] As illustrated in FIG. 14, the engagement ring 4a, 4b includes, in addition to the three recesses 33 for the levers 31, three oblique guides 33a. These are configured to receive a corresponding number of hooks 6a, 6b that protrude from the opposite hemispherical shell 1a, 1b of the core 1. During the separation of the two hemispherical shells 1a, 1b, the hooks 6a, 6b are forced to follow a linear movement parallel to the spatial diagonal, as they are guided by specific recesses 37a, 37b formed in the opposite hemispherical shell 1a, 1b, as illustrated in particular in FIGS. 15 and 16, where it can be seen that a hook 6a, 6b of one hemispherical shell 1a is guided within a recess 37b, 37a of the other hemispherical shell 1. It is therefore necessary for the engagement rings 4a, 4b to be able to rotate in order to allow the hooks 6a, 6b to perform their movement. A locked engagement ring 4a, 4b traps the opposite hook 6a, 6b in its position.

[0087] When all the levers 31 have been actuated, allowing both engagement rings 4a, 4b to rotate freely, the pulling force applied by the user to separate the two halves of the cube actuates the mechanism that enables the hooks 6a, 6b to slide within the corresponding recesses 37b, 37a of the opposite hemispherical shell 1b, 1a.

[0088] It should be noted that, when the two hemispherical shells 1a, 1b are separated from one another, and the engagement ring 4a, 4b has undergone the rotation caused by the separation of the two shells, the lever 31 is held in an extracted position with respect to the corresponding recess 33, as shown in FIG. 18. Since the first end 31 of the lever 31 has a fork-shaped configuration that retains the column 38 of the central cubie 3, the fact that the lever 31 is in an extracted position relative to the recess 33 of the engagement ring 4a, 4b causes the column 38and therefore the corresponding facet 30 of the central cubie 3to remain in the pressed position. Consequently, the shaped pins 32 also remain in the pressed position, that is, inserted into the corresponding through-holes 52, 72 of the flanges 51, 71 of the peripheral cubies 5, 7, thus holding them in place. This ensures that the peripheral cubies 5, 7 remain attached to their respective half of the cube 100 when it is separated into two halves. Otherwise, when the cube 100 is opened, the individual peripheral cubies 5, 7 could detach from the core 1, making reassembly extremely inconvenient for the user. FIGS. 4 and 5 show that the inner structure 34 of the central cubies 3 remains pressed, and therefore the pins 32 remain inserted in the holes 52, 72.

[0089] In essence, when the cube 100 is open, the coded pins 32 are held in the pressed position (as seen, the central facets 30 are retained by the levers 31, which are prevented from returning to their resting position by the engagement ring 4a, 4b).

[0090] In this way, the user is not required to actively keep the central cubies 3 pressed in order to prevent the opened cube 100 from disassembling.

[0091] It should also be noted that, in order to allow the opening of the cube 100 and its separation into two halves, it is preferable that the pins 32 of the central cubies 3 belonging to one half of the cube 100 do not retain the peripheral cubies 5, 7, which instead belong to the opposite half. To this end, as illustrated in particular in FIG. 6, the flanges 51, 71 of the peripheral cubies 5, 7 that are located along the separation plane are provided, at the position corresponding to the pins 32 of the central cubies 3 belonging to the other half of the cube 100, with open cutouts 53, 73 instead of shaped holes 52, 72. These cutouts 53, 73 are open in the direction of separation of the two cube halves and allow the peripheral cubies 5, 7 of one half of the cube 100 to slide off the pins 32 of the central cubies 3 of the opposite half.

[0092] For each face of the cube 100, among the eight coded pins 32 provided on the facet 30 of the central cubie 3, only one corner pin and one edge pin encounter the open cutouts 53, 73 instead of the coded holes 52, 72. These cutouts 53, 73 belong to peripheral cubies 5, 7 that are still controlled by one (in the case of an edge) or two (in the case of a corner) additional coded pins 32 from other faces. It is therefore ensured that only when the entire cube 100 is in a completely solved configuration is it possible to press all six central facets 30 simultaneously in order to open it.

[0093] Closing the cube 100 simply consists in reversing the opening sequence. The mechanisms are fully reversible: the three hooks 6a, 6b of one half of the cube 100, by engaging with the oblique guides 33a of the engagement ring 4b, 4a of the opposite half, cause its rotation, thereby repositioning the recesses 33 so that the ends 31 of the levers 31 can once again rest within them.

[0094] The springs (not illustrated) that tend to return the central facets 30 to their extracted resting position also draw with them the first end 31 of the levers 31connected via the fork-shaped geometry of the columns 38so that no resistance is encountered, and the cube 100 automatically returns to its original configuration, in which it can once again be manipulated (scrambled and solved) like a traditional cube.

[0095] A further feature of the puzzle cube 100 is that the facets 50, 50x, 70, 70x, 70y of the peripheral cubies 5, 7 are removable and repositionable at will. This allows the user to choose a different opening combination other than the classic solved cube with uniformly colored faces, enabling any alternative customized color scheme. Various technical solutions can be adopted to achieve this effect. For example, the facets 50, 70 may include fastening means such as small retaining tabs, generically indicated with reference numerals 58 and 78, which allow the facets to be snap-fitted or detached under pressure. Moreover, when the facets 50, 70 of the peripheral cubies 5, 7 are removed, the interior of the cubies 5, 7 becomes visible, but this does not reveal any information about the secret opening mechanism. Alternatively, the facets 50, 50x, 70, 70x, 70y of the peripheral cubies 5, 7 may comprise removable and re-applicable colored stickers.

[0096] It is also possible to equip the cube 100 with magnets to promote the correct alignment of cubies 3, 5, 7 with one another.

[0097] In an unillustrated variant of the cube 100, the portion of the flanges 51, 71 of the peripheral cubies 5, 7 that face the separation line between the two halves of the cube 100 may be intact, without cutouts and/or holes, while the central cubies 3 do not have two of the eight coded pins 32one corner pin and one edge pin. In this way, opening would be possible only if the central cubie 3 is rotated so that the positions of the missing pins 32 align with the portions of the flanges 51, 71 that are without holes. The effect is that, in order to open the cube 100, it is not sufficient to bring all the peripheral cubies 5, 7 into the correct positions; it is also necessary to correctly orient all the central cubies 3, exactly as required for solving so-called supercubes, that is, cubes that are considered solved only when the cubies are both correctly positioned and correctly oriented on their respective faces.

[0098] In a further variant, illustrated in FIG. 19, the eight pins 32 of the central facets 30 are not coded, meaning they do not have a shape selected from a plurality of shapes, but would be simple pushing pins. Instead, a coded element 172that is, an element having a shape selected from a plurality of shapeswould be housed directly in the flanges 51, 71 of the peripheral cubies 5, 7, taking care that the upper surface (i.e., the one that can be glimpsed through the gaps of the cube) does not provide any information about the underlying coding. The verification of the code would take place by means of coded holes 12, which in this case would be formed in the core 1. The operation resulting from this would be entirely equivalent to what has already been described. The advantage of this variant lies in the fact that the coded shapes of the holes 52, 72 are completely hidden from view. Indeed, in this way, the coded holes present in the flanges 51, 71 of the edge cubies 5 and corner cubies 7 cannot be seen even if the cubies 5, 7 are forced slightly apart by exploiting the inevitable tolerances and play between the parts. As a result, it is possible to prevent in advance any attempthowever laboriousto reconstruct the identity of each peripheral cubie 5, 7, which, combined with trial-and-error exploration of the central cubies 3, could otherwise allow the cube 100 to be cracked.It has been effectively found that the puzzle cube with internal secret compartment, according to the present invention, fulfils the intended purpose and objectives, as it allows the cube to be opened in order to access the secret compartment located in the central body, namely in the internal core of the puzzle cube.

[0099] Another advantage of the puzzle cube, according to the invention, lies in the fact that it can be opened-and therefore allow access to the secret compartment-only when it is solved according to a predetermined combination.

[0100] A further advantage of the puzzle cube, according to the invention, is that it features an opening mechanism that is solid and durable over time.

[0101] The puzzle cube with internal secret compartment, as conceived, is susceptible to numerous modifications and variants, all falling within the scope of the inventive concept.

[0102] Moreover, all details may be replaced by other technically equivalent elements.

[0103] In practice, the materials used-provided they are compatible with the intended use as well as the dimensions and contingent shapes, may be of any kind depending on requirements.