Removable assembly for a skateboard

Abstract

A removable assembly for a skateboard comprises a base piece (1) configured for the fixing thereof to a board (40); an upper piece (7) configured for the fixing thereof in a removable manner to a wheel unit (36), the base piece (1) being coupled to the upper piece (7) such that they can rotate with respect to each other; and a torsion spring (6) arranged between the base piece (1) and the upper piece (7) to exert a force aimed at causing them to regain a neutral position.

Claims

1. A removable assembly for converting a skateboard formed by a board, a front wheel unit and a rear wheel unit, into a surfskate, the removable assembly comprising: a base piece (1) configured for the fixing thereof to the board (40) of the skateboard; an upper piece (7) configured for the fixing thereof in a removable manner to the front wheel unit (36), and a torsion spring (6) arranged between the base piece (1) and the upper piece (7); where the base piece (1) is coupled to the upper piece (7) such that they can rotate with respect to each other; and where the torsion spring (6) exerts a force aimed at causing both pieces (1,7) to regain a neutral position corresponding to a rectilinear displacement of the skateboard and where when the removable assembly is attached to the board and the front wheel unit attached to the upper piece (7), a first distance between the board (40) and the front wheel unit is increased as compared to when the front wheel unit is attached directly to the board (40), wherein a second distance between the front wheel unit and the rear wheel unit of the skateboard is unchanged when the removable assembly is disposed between the board and the front wheel unit.

2. The assembly according to claim 1, wherein the torsion spring (6) is housed in an essentially cylindrical cavity formed between a first flange (50) of the base piece (1) and a second flange (51) of the upper piece (7) which fits into the interior of said first flange such that the torsion spring (6) is fully protected from the exterior in order to prevent the entry of dirt or foreign elements which may affect the behavior thereof.

3. An assembly according to claim 2 which comprises at least one fixing washer (65, 65) which is internally fixed to one of the pieces (1, 7) through an area of the housing cavity of the torsion spring (6) by means of two fixing screws (67) which pass through two fixing holes (68) situated in said at least one fixing washer (65, 65) which also comprises at least two insertion holes (66) of different diameters which can receive a pin of the torsion spring (6).

4. The assembly according to claim 1, wherein a first pin of the torsion spring (6) is coupled to a first hole (14) of the base piece (1) and a second pin of the torsion spring (6) is coupled to a second hole (28) of the upper piece (7).

5. The assembly according to claim 4, wherein the base piece (1) comprises an auxiliary hole (13) perpendicular to the first hole (14) for the fixing of the first pin of the torsion spring (6) and the upper piece (7) comprises an auxiliary hole (27) perpendicular to the second hole (28) for the fixing of the second pin of the torsion spring (6).

6. The assembly according to claim 1, wherein the base piece (1) comprises a stop (18) which cooperates with another stop (30) of the upper piece (7) to limit the rotational angle between the base piece (1) and the upper piece (7).

7. The assembly according to claim 6, wherein the stop (18) of the base piece (1) and the stop (30) of the upper piece (7) are arranged such that they allow a rotation of between 40 and 50 to each side of the neutral position.

8. The assembly according to claim 1, wherein the rotary coupling between the base piece (1) and the upper piece (7) comprises a lower axial bearing (4) situated between the base piece (1) and the upper piece (7), an upper axial bearing (10) situated between the upper piece (7) and a single locking nut (11) of the assembly, and a bolt (2) which passes through the base piece (1), the lower axial bearing (4), the torsion spring (6), the upper piece (7) and the upper axial bearing (10), the upper piece (7) rotating in relation to the base piece (1) around said bolt (2).

9. The assembly according to claim 8, wherein the bolt (2) is fixed to the base piece (1) by means of screwing.

10. The assembly according to claim 1, wherein the upper piece (7) comprises a flat surface (25) intended for the fixing of the wheel unit (36).

11. The assembly according to claim 10, wherein the flat surface (25) comprises holes (24) for the fixing of the wheel unit (36).

12. The assembly according to claim 1, wherein the base piece (1) comprises a flat surface (23) intended for the fixing of the board (40).

13. The assembly according to claim 12, wherein the flat surface (23) comprises holes (21) for the fixing of the board (40).

14. The assembly according to claim 1, comprising a rotation-limiting element (61) which comprises a coupling recess (63) which can be coupled to a stop (30) of the upper piece (7) and fixed to the latter such that it reduces the permitted rotation between the upper piece (7) and the base piece (1).

15. The assembly according to claim 1, which comprises locking means (60) which prevent the rotation between the upper piece (7) and the base piece (1).

16. A removable assembly for converting a skateboard formed by a board, a front wheel unit and a rear wheel unit, into a surfskate, the removable assembly comprising: a base piece (1) configured for the fixing thereof to the board (40) of the skateboard; an upper piece (7) configured for the fixing thereof in a removable manner to the front wheel unit (36), and a torsion spring (6) arranged between the base piece (1) and the upper piece (7); where the base piece (1) is coupled to the upper piece (7) such that they can rotate with respect to each other; and where the torsion spring (6) exerts a force aimed at causing both pieces (1,7) to regain a neutral position corresponding to a rectilinear displacement of the skateboard and where when the removable assembly is attached to the board and the front wheel unit attached to the upper piece (7), the distance between the board (40) and the front wheel unit is increased as compared to when the front wheel unit is attached directly to the board (40), wherein the upper piece (7) includes a flat surface (25) having the front wheel unit of the skateboard affixed there to when the removable assembly is used on the board (40); a first pin of the torsion spring (6) is coupled to a first hole (14) of the base piece (1) and a second pin of the torsion spring (6) is coupled to a second hole (28) of the upper piece (7); and the base piece (1) comprises an auxiliary hole (13) perpendicular to the first hole (14) for the fixing of the first pin of the torsion spring (6) and the upper piece (7) comprises an auxiliary hole (27) perpendicular to the second hole (28) for the fixing of the second pin of the torsion spring (6).

17. The assembly according to claim 16, wherein the torsion spring (6) is housed in an essentially cylindrical cavity formed between a first flange (50) of the base piece (1) and a second flange (51) of the upper piece (7) which fits into the interior of said first flange such that the torsion spring (6) is fully protected from the exterior in order to prevent the entry of dirt or foreign elements which may affect the behavior thereof.

18. An assembly according to claim 17, further comprising at least one fixing washer (65, 65) which is internally fixed to one of the pieces (1, 7) through an area of the housing cavity of the torsion spring (6) by means of two fixing screws (67) which pass through two fixing holes (68) situated in said at least one fixing washer (65, 65) which also comprises at least two insertion holes (66) of different diameters which can receive a pin of the torsion spring (6).

19. The assembly according to claim 16, wherein the base piece (1) comprises a stop (18) which cooperates with another stop (30) of the upper piece (7) to limit the rotational angle between the base piece (1) and the upper piece (7).

Description

DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows an exploded perspective view of an exemplary assembly according to the invention.

(2) FIGS. 2A and 2B respectively show an upper view of the assembly and a section along the plane of symmetry A-A thereof.

(3) FIGS. 3A and 3B show two sections along the plane of symmetry of the base piece viewed respectively from above and from below.

(4) FIGS. 4A and 4B show two sections along the plane of symmetry of the upper piece viewed respectively from above and from below.

(5) FIGS. 5A, 5B and 5C respectively show a lower view of an assembly according to the invention fixed to a traditional wheel unit, a section along the plane of symmetry A-A thereof and a perspective view of said assembly and of the traditional wheel unit.

(6) FIGS. 6A, 6B and 6C respectively show side, bottom and perspective views of the assembly of the invention fixed to a traditional wheel unit and a board.

(7) FIGS. 7A and 7B respectively show a view of the assembly of the invention with the torsion axis in a neutral position and a complete view of the assembly of the invention fixed to a traditional wheel unit and to a board where the torsion axis is in a neutral position.

(8) FIGS. 8A and 8B respectively show a view of the assembly of the invention with the torsion axis in the more open position and a complete view of the assembly of the invention fixed to a traditional wheel unit and to a board where the torsion axis is in the more open position.

(9) FIG. 9 shows a perspective view of the upper piece mounted in a wheel unit in which locking means can be observed which allow the rotation between the upper piece and the base piece to be prevented.

(10) FIG. 10 shows a perspective view like the one of FIG. 9 with the base piece coupled and fixed to the upper piece with the rotation locked with respect to the latter by means of locking means.

(11) FIG. 11 shows a perspective view of a variant of the upper piece which incorporates a hole for the arrangement of locking means like those depicted in FIG. 9 and which comprises a stop configured for receiving fixing means for the arrangement of a rotation-limiting element.

(12) FIG. 12 shows a perspective view of an element limiting rotation to 30, provided for being fixed on the stop of the upper piece depicted in FIG. 11.

(13) FIG. 13 shows a perspective view in which an alternative for the fixing of the torsion spring has been depicted, the base piece, the torsion spring and an upper fixing washer with the respective fixing screws thereof having been depicted, but without the upper piece having been depicted.

(14) FIG. 14 shows a perspective view of an embodiment of the fixing washer.

(15) FIG. 15 shows an exploded view of the entire assembly according to the embodiment depicted in FIGS. 13 and 14.

(16) FIGS. 16 and 17 respectively show a longitudinal and transversal section of the embodiment depicted in FIG. 15.

DETAILED DESCRIPTION OF THE INVENTION

(17) FIG. 1 shows an exploded view of an exemplary removable assembly according to the present invention. The base piece (1), which in this example is obtained by aluminum gravity casting with post heat treatment, is fixed by means of threading to the lower end of a steel bolt (2) with threading at each one of the ends thereof. This bolt (2) forms the rotational axis around which the upper piece rotates (7) owing to an axial needle bearing system arranged around said bolt (2). Specifically, the bearing system is formed by two washers (3) and an axial needle bearing (4) and is arranged between the base piece (1) and the upper piece (7) to allow the rotation of the second piece with respect to the first.

(18) The torsion spring (6) is provided around the axial needle bearing system. As can be observed in greater detail in subsequent figures, the torsion spring (6) is located at the bottom of an essentially cylindrical cavity formed by a first cylindrical flange (50) of the base piece (1) and is fixed to the same owing to a first hole (14) which receives a pin of the torsion spring (6). An auxiliary hole (13) perpendicular to the first hole (14) allows for the insertion from the exterior of the assembly of a threaded fixing bolt (5) which prevents the exit of the pin from the torsion spring (6). The cavity is completed with the insertion of a second cylindrical flange (51) of the upper piece (7) in the interior of the first flange (50) of the base piece (1) until it is supported on the bottom. A space or cavity is produced in an essentially closed cylindrical manner between both flanges (50, 51) which protects the torsion spring (6) from the entry of dirt and foreign elements. What is more, this cavity formed by the first flange (50) of the base piece (1) in combination with the second flange (51) of the upper piece (7) not only houses the torsion spring (6), but also the first axial bearing system which is thus also protected. The torsion spring (6) is fixed to the upper piece (7) by means of inserting another pin into a second hole (28). An auxiliary hole (27) perpendicular to the second hole (28) allows for the insertion of a bolt for the fixing of the pin of the torsion spring (6).

(19) The upper piece (7), also obtained by aluminum gravity casting with post heat treatment rotates around a bronze bearing (8) to which it is joined under pressure and the function of which is to limit the friction during the rotation. For mounting, the bearing (8) is introduced through the upper end of the bolt (2) until it is supported on the washer (3). Then, once the upper piece (7) is installed and the torsion spring (6) fixed by means of the threaded bolts (5), a second axial needle bearing system formed by another two washers (9) and an axial needle bearing (10) is installed and they are introduced through the upper end of the bolt (2) and are fixed by means of a single self-locking nut (11).

(20) The position of all these elements when the assembly is completely mounted is observed in the section of FIG. 2A along the plane of symmetry of the complete mounted assembly shown in FIG. 2B.

(21) FIGS. 3A and 3B show two views of a section along the plane of symmetry of the base piece (1). The base piece (1) has a flat surface called base (23) intended to be supported on a board (40) of the skateboard for the fixing thereof to the same. To this end, countersunk screws are introduced by way of the threaded bores (21) of the base (23) and holes (37) corresponding to the front part or nose (38) of the skateboard. The base piece (1) also has a threaded hole (12) located in the center of the essentially cylindrical first flange (50) which receives the torsion spring (6) which serves for the fixing of the lower end of the bolt (2). The washer (3) of the first axial bearing system is supported on a horizontal circular surface (15) on the bottom of the cavity formed by the first flange (50), while the torsion spring (6) is located on a horizontal circular surface (16) with a greater radius than the previous surface. This horizontal circular surface (16) has a first vertical hole (14) intended to receive a pin of the torsion spring (6). A hole (13) perpendicular to said first vertical hole (14) allows for the introduction of a bolt (5) for fixing the pin.

(22) The base piece (1) also comprises a stop (18) which projects from the first flange (50) with the aim of limiting the amplitude of the rotation of the upper piece (7) in relation to the base piece (1), as is described in greater detail in relation to FIGS. 7 and 8. The surface (22) is the front part of the base piece (1) according to the direction of the movement of the skateboard and protects the interior of the cavity from impacts and dirt. The surface (19) is perpendicular to the rotational axis of the bolt (2). The area (20) is an empty area for reducing weight.

(23) Similarly, FIG. 4 shows two views of a section along the plane of symmetry of the upper piece (7). A flat surface can be observed which forms the base (25) intended to be supported on an equally flat surface of the traditional wheel unit (36) for the fixing thereof to the same. To this end, screws are introduced through the threaded holes (24) arranged on the base (25) and in corresponding holes of the wheel unit (36). The upper piece (7) also has a reamed bore (26) intended to receive the bearing (9) under pressure. The laterals of said bore (26) form the second essentially cylindrical flange (51) which, as previously mentioned, is introduced into the first flange (50) of the base piece (1) to protect the spring (6) and the first axial bearing system. The surface (31) of the upper end of the second flange (51) forms the support on which the washer (3) of the first axial bearing system is located. The axial spring (6) is supported on a circular surface external to said second flange (51) in which the second hole (28) is located which receives the pin of the spring. An auxiliary threaded bore (27) perpendicular to the second hole (28) allows a bolt (5) for fixing the pin of the torsion spring (6) to be introduced from the exterior of the assembly.

(24) The surface (29) is a continuation of the base surface (25), although it forms a small angle with the same. The surface (33) is located on the side opposing the upper piece (7) and is the surface from which the second flange (51) projects and where the second hole (28) is located. The surfaces (29, 33) are parallel to each other and perpendicular to the rotational axis of the bolt (2). The washer (9) of the second axial bearing system is supported on the surface (29). The surface (32) is the front part of the upper piece (7) and protects the assembly against possible impacts, in addition to providing it with rigidity. The ribs (34) also provide the assembly with rigidity. The upper piece (7) also has a stop (30) which projects from the surface (33) at a certain distance from the second flange (51), in a position corresponding to that of the stop (18) of the base piece (1). The stop (30) of the upper piece (7) cooperates with the stop (18) of the base piece (1) to limit the rotational angle of the first piece in relation to the second piece.

(25) In order to fix different torsion springs (6), which have different resistances and section diameters, alternatively to the arrangement of threaded fixing bolts (5), an embodiment is envisaged, as has been depicted in FIGS. 13 to 17 which comprises a fixing washer (65, 65) for each pin of the torsion spring such that an upper fixing washer (65) is internally fixed to the upper piece (7) at the area of the housing cavity of the torsion spring (6), while a lower fixing washer (65) is internally fixed to the base piece (1) at the area of the housing cavity of the spring (6). This fixing is carried out by means of two fixing screws (67), which pass through two fixing holes (68) situated on the fixing washers (65, 65). As can be observed in the exploded view of FIG. 15, it is envisaged that one toothed washer (69) is provided for each fixing screw (67) in order to ensure that there is no movement between each fixing screw (67) and the corresponding piece (1, 7).

(26) Each fixing washer (65, 65) comprises at least two insertion holes (66), although there may be more, preferably three, of different diameters, such that they can be passed through, minimizing the clearance through the torsion spring pins (6) of different diameters.

(27) The possibility is envisaged of the angular arrangement of the insertion holes (66) varying between the upper fixing washer (65) and the lower fixing washer (65) for the purpose of being able to resolve possible misalignments of the pins of the torsion spring (6).

(28) This alternative is more efficient when maintaining said fixing in spite of the vibrations to which it is subjected during the time of use thereof.

(29) By means of this embodiment, unlike the previous ones in which the spring (6) is directly fixed to the upper pieces (7) and base (1), because the spring (6) is made of steel, it avoids the pieces (1, 7), which are usually made of aluminum, deteriorating, therefore the fixing washers (65, 65) are preferably made of steel and since they are each bound at two points by means of the fixing screws (67) to the upper pieces (7) and base (1), this problem is avoided. This is also why the aluminum pieces (1, 7) are not threaded in the area through which the fixing screw (67) passes, but rather it is opted to fix it, preferably with toothed washers (69) as are shown in FIG. 15 since the thread with the stresses would end up wearing the aluminum and losing the function thereof.

(30) FIG. 5A shows the assembly fixed to a conventional wheel unit (36) of a skateboard. FIG. 5B shows a detail of the section along the plane A-A of FIG. 5A, and FIG. 5C shows a perspective of both elements still not joined. As was previously described, the wheel unit (36) is joined to the base surface (25) of the upper piece (7) by means of screws which are introduced into the threaded bores (24) and into the bores (35) with which the wheel unit (36) is provided.

(31) FIG. 6 shows three views of a skateboard already with the assembly mounted between the conventional wheel assembly (36) of the nose (38) of the skateboard and the board (40). The rear wheel unit (36) located at the tail (39) does not require the installation of the assembly of the invention, therefore it is recommended to elevate it by means of shims so that the nose (38) of the skateboard is not elevated too much. The rear wheel unit (36) performs a similar function to that of the keel of a surfboard during the transformation of the skateboard to a surfskate. In these figures, it is also observed how the original distance between axes of the skateboard is maintained.

(32) FIG. 7A shows a detail of the assembly with a torsion spring (6) in a neutral position corresponding to a rectilinear displacement of the skateboard. FIG. 7B shows the assembly in the same position already fixed to the board (40) and to the wheel unit (36). In this neutral position, no type of force is exerted on the longitudinal laterals of the board (40) and both the stop and the pins of the torsion spring (6) are maintained in the plane of symmetry aligned with the bolt (2) which is the rotational axis.

(33) FIG. 8A shows a detail of the assembly of the torsion spring (6) in one of the more open positions in a clockwise direction. FIG. 8B shows the assembly in the same position already fixed to the board (40) and to the wheel unit (36). In this open position of the spring, with a maximum rotation of 45, it now exerts a force F on the longitudinal lateral of the board (40). This causes the upper piece (7) to rotate with respect to the bolt (2) until the stop (30) impacts the stop (18) of the base piece (1). During this entire movement, the pins of the torsion spring (6) remain fixed respectively to the base piece (1) and to the upper piece (7).

(34) FIG. 9 shows a perspective view of the upper piece (7) mounted on a wheel unit (36) in which according to an embodiment variant, locking means (60) can be observed, which consist of two screws which allow the rotation between the upper piece (7) and the base piece (1) to be prevented, which can be implemented by the user in the case that they wish to avoid the rotation between both pieces (1, 7).

(35) FIG. 10 shows a perspective view like the one of FIG. 9 with the base piece (1) coupled and fixed to the upper piece (7) with the rotation locked with respect to the latter by means of locking means (60).

(36) FIG. 11 shows a perspective view of a variant of the upper piece (7) which incorporates a single hole for the arrangement of locking means (60) which in this case consists of a single screw in a similar manner to that depicted in FIG. 9.

(37) In addition, the upper piece (7) depicted in FIG. 11 also comprises a stop (30) which is configured for receiving fixing means for the arrangement of a rotation-limiting element (61). Said fixing means can consist of a screw passing through a fixing hole (62) of the rotation-limiting element (61) which has been depicted in FIG. 12, where a perspective view of the rotation-limiting element (61) is shown, the lateral walls of which (64) define the complete rotational angle permitted, in the case depicted it is 30. The rotation-limiting element (61) comprises a coupling recess (63) which is coupled to the stop (30) of the upper piece (7), being fixed to the latter by means of the screw passing through the fixing hole (62), thus reducing the rotation permitted between the upper piece (7) and the base piece (1) which can be selected by the user.

(38) When the force F ceases to be exerted on the longitudinal lateral of the board (40), the torsion spring returns the accumulated energy and returns the assembly to the neutral position thereof corresponding to the rectilinear displacement. By alternating the application of force on the laterals of the board, simulating the way in which the body moves on a surfboard in order to cause it to turn towards both sides, a movement towards the front of the surfskate is produced.