Title:
Steering Device For Sports Articles Provided With Supporting And Sliding Elements In An In-Line Arrangement
Kind Code:
A1


Abstract:
The present invention refers to a steering device for sports articles (1) adapted to slide on a supporting surface (2) by means of a plurality of supporting and sliding elements (3) provided in an in-line arrangement; the steering device comprises a chassis (5), to which there is associated at least a carriage 6a adapted to swing relative to said chassis (5), against the force of elastic means (17, 18), about an axis (7) that is inclined by an angle (x with respect to said supporting surface (2) and lies substantially on the median longitudinal plane (4) of the chassis (5). The carriage (6)a is adapted to support at least two supporting and sliding elements (3) in a manner that the respective support axes (25, 26) come to lie substantially parallel to said supporting surface (2) on opposite sides with respect to the pivoting, i.e. swinging centre (27) of said carriage 6a relative to said chassis (5).



Inventors:
Battocchio, Andrea (Romano d'Ezzelino, IT)
Application Number:
10/573594
Publication Date:
09/06/2007
Filing Date:
05/06/2004
Primary Class:
International Classes:
A63C17/06
View Patent Images:
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Primary Examiner:
PHAN, HAU VAN
Attorney, Agent or Firm:
WENDEROTH, LIND & PONACK, L.L.P. (Washington, DC, US)
Claims:
1. Steering device for sports articles (1, 101, 201, 301, 401) adapted to slide on a supporting surface (2, 102, 202, 302, 402) by means of a plurality of supporting and sliding “elements (3, 103, 203, 303, 403) provided in an in-line arrangement, said steering device comprising a chassis (5, 105, 205, 305, 405), to which there is associated at least a carriage (6a, 6b, 106a, 106b, 206a, 206b, 306a, 306b, 406a, 406b) for supporting at least one of said supporting and sliding elements (3, 103, 203, 303, 403), said carriage (6a, 6b, 106a, 106b, 206a, 206b, 306a, 306b, 406a, 406b) being adapted to swing relative to said chassis (5, 105, 205, 305, 405), against the force of elastic means (17, 18, 417), about an axis (7, 107a, 107b, 207a, 207b, 307a, 307b, 407a, 407b) that is inclined by an angle α with respect to said supporting surface (2, 102, 202, 302, 402) and lies substantially on the median longitudinal plane (4, 404) of said chassis (5, 105, 205, 305, 405), characterized in that at least two of said supporting and sliding elements (3, 103, 203, 303, 403) are supported by said carriage (6a, 6b, 106a, 106b, 206a, 206b, 306a, 306b, 406a, 406b) at respective support axes (25, 26, 125, 126, 225, 226, 325, 326, 425, 426) arranged in a manner that is substantially parallel to said supporting surface (2, 102, 202, 302, 402) on opposite sides with respect to the swinging centre (27, 127, 227, 327, 427) of said carriage (6a, 6b, 106a, 106b, 206a, 206b, 306a, 306b, 406a, 406b) relative to said chassis (5, 105, 205, 305, 405).

2. Steering device according to claim 1, wherein said chassis (5, 105, 205, 305) has, approximately in correspondence to at least one of the end portions (8a, 8b) thereof, a support member (9) that is provided with at least a surface (9a) that is inclined by an angle β relative to said supporting surface (2, 102, 202, 302), said angle β being preferably complementary to said angle α.

3. Steering device according to claim 2, wherein said carriage (6a, 6b, 106a, 106b, 206a, 206b, 306a, 306b) is provided with an arm (11) for the connection to said support member (9), said arm featuring a surface (11a) facing towards and counter-shaped, i.e. shaped complementarily, to the surface (9a) of said support member (9).

4. Steering device according to claim 3, wherein from opposite sides with respect to said arm (11) there extend a first and a second fork (13, 14), each one of which supporting a respective one of said supporting and sliding elements (3, 103, 203, 303) in correspondence to said support axes (25, 26, 125, 126, 225, 226, 325, 326).

5. Steering device according to claim 1, wherein said elastic means (17, 18) interact with said arm (11) to elastically contrast the swinging movement of said carriage (6a, 6b, 106a, 106b, 206a, 206b, 306a, 306b).

6. Steering device according to claim 5, wherein said elastic means (17, 18) are housed within respective accommodations (19, 20) provided in said support member (9), and interact with respective projections (23, 24) extending from said arm (11).

7. Steering device according to claim 1, wherein said swinging axis (7, 107a, 107b, 207a, 207b, 307a, 307b) is inclined by an angle comprised between, but not including, 0° and 90° in respect to said supporting surface (2, 102, 202, 302).

8. Steering device according to claim 7, wherein said swinging axis (7, 107a, 107b, 207a, 207b, 307a, 307b) extends approximately in correspondence to, or above, the support axis (25, 125, 225, 325) of said supporting and sliding element (3, 103, 203, 303) located adjacent the middle portion of the chassis (5, 105, 205, 305).

9. Steering device according to claim 1, wherein to said chassis (5, 105, 205, 305, 405) there are associated a first and a second carriage (6a, 6b, 106a, 106b, 206a, 206b, 306a, 306b, 406a, 406b) arranged approximately in correspondence to the end portions (8a, 8b, 408a, 408b) of said chassis (5, 105, 205, 305, 405), each such carriage supporting a pair of said supporting and sliding elements (3, 103, 203, 303, 403).

10. Steering device according to claim 9, wherein said first and second carriage (6a, 6b, 206a, 206b) are arranged to symmetrically oppose each other.

11. Steering device according to claim 9, wherein said supporting and sliding elements (3, 103, 203, 303, 403) are constituted by at least four wheels.

12. Steering device according to claim 11, wherein said wheels (3, 103, 203, 303, 403) are of a different size.

13. Steering device according to claim 9, wherein the lines (30, 330a, 330b, 430) connecting the support axis (25, 26, 325a, 326a, 325a, 326b, 425, 426) of said supporting and sliding elements (3, 303, 403) are arranged parallel to the supporting surface (2, 302, 402).

14. Steering device according to claim 12, wherein at least two front wheels (303a, 303b) located at the front of said chassis (305) have a smaller diameter than at least two rear wheels (303c, 303d) located at the rear of said chassis (305), the line (330a) connecting the support axis (325a, 326a) of said front wheels (303a, 303b) being located closer to said supporting surface (302) than the line (330b) connecting the support axis (325b, 326b) of said rear wheels (303c, 303d).

15. Steering device according to claim 12, wherein the lines (130a, 130b, 230a, 230b) connecting the support axis (125a, 126a, 225a, 226b) of said wheels (103, 203) are arranged inclined in respect to the supporting surface (102, 202).

16. Steering device according to claim 12, wherein the front wheel (103a) and the third wheel (103c) from the front of the chassis (105) are smaller in diameter than the second wheel (103b) and the rear wheel (103d), said lines (130a, 130b) being inclined along the same direction.

17. Steering device according to claim 12, wherein the wheels (203b, 203c) located central in the central portion of said chassis (205) are smaller in diameter that the front wheel (203a) and the rear wheel (203d), the lines (230a, 230b) respectively connecting the first support axis (225a, 226a) and the second support axis (225b, 226b) being oppositely inclined in respect to the supporting surface (202).

18. Steering device according to claim 12, wherein said swinging axis (407a, 407b) are arranged inclined at an angle of 90° relative to said supporting surface (402) and lying substantially on the longitudinal median plane of said chassis (405).

19. Steering device according to claim 18, wherein the wheels (403a) arranged at the front and at the rear of said chassis (405) have a width which is smaller than the width of the wheels (403b) arranged at a central portion of said chassis (405).

20. Sports article adapted to slide on a supporting surface by means of a plurality of supporting and sliding elements aligned along a same longitudinal axis, characterized in that it comprises a steering device according to claim 1.

21. Sports article according to claim 20, wherein said supporting and sliding elements comprise wheels, ice blades, short skis and the like.

Description:

The present invention refers to a steering device for sports articles adapted to slide on a supporting surface by means of a plurality of supporting and sliding elements provided in an in-line arrangement, i.e. aligned along a same longitudinal axis. These sports articles, which may for instance be constituted by in-line roller skates, ski-rolls, scooters, sledges, ski-scooters and the like, are intended for sliding either on the ground by rolling thereupon, or on a snow blanket or ice by gliding thereupon.

An important requirement that such sports articles are supposed to meet is the leading and running precision that they must ensure when re-directing the course, i.e. when the skating or sliding direction is being changed. This is particularly true in connection with such sports activities as for instance street or ice hockey or figure skating, which involve continuous and abrupt changes of the sliding course. The possibility of performing continuous turns with a curving radius as small as possible, is therefore a problem that is particularly felt when using these articles, with particular reference to in-line roller skates and ice skates.

The technical solution disclosed in U.S. Pat. No. 2,204,280, filed with a claimed Swiss priority of Aug. 17, 1937, is aimed at solving—at least partially—the above-indicated technical problem. This patent refers in fact to a skate with two in-line wheels, each one of which is supported by a respective fork that is pivotally connected—in correspondence to a lower portion thereof and outside of the vertical plane passing through the axis of the wheels—to a support member provided in an inclined arrangement relative to the chassis, so as to enable the same fork to swing transversally against the action of elastic elements; the pivoting centres of the two forks are situated on opposite sides and externally with respect to the axes of the respective wheels, so that these wheels, which are aligned with each other when running along a rectilinear course, are caused to automatically deflect into an oblique position when a curving action is being performed.

A major drawback of this prior-art approach lies in the poor stability of the skate, as well as in the difficulty that is encountered when trying to obtain a continuous, smooth curving effect owing to the distance existing from the front wheel to the rear wheel. As a matter of fact, although both of them are actually provided with a steering device of their own, the two wheels are situated too far from each other to be able to arrange themselves according to such an ideal arc of curvature as to enable the skater to curve in a smooth, continuous manner. As a result, the skater is forced to intervene with a number of progressive adjustments of the trajectory so as to be able to move over the entire curve, which is therefore performed and completed in a discontinuous manner. In addition, owing again to said distance between the wheels, when performing a curving manoeuvre the forks may be subject to vibrations due to the quite significant stresses acting upon each wheel, and these vibrations may bring about a substantial instability of the skate, with a resulting difficulty being found in leading and running the skate with the due accuracy exactly during such a critical phase as the one implying a curve, i.e. a change of direction.

A further drawback lies in the fact that the steering device of the above-cited prior-art solution is only capable of working in connection with wheels having a flat tread. In fact, it is by inclining the chassis sideways that a change of direction is obtained, thereby determining a reaction of the supporting surface on the wheels, which eventually relieves itself onto the pins that pivotally connect the forks to the support members, thereby causing the forks themselves to rotate relative to the corresponding support members.

It therefore is a main object of the present invention to overcome the above-cited drawbacks of prior-art solutions by providing a steering device for sports articles adapted to slide on a supporting surface by means of a plurality of supporting and sliding members provided in an in-line arrangement, which is reliable and safe in use.

Within the above general object, a purpose of the present invention is to provide a steering device, which enables a change of direction, i.e. a curve, to be performed in a smooth and continuous manner, while maintaining full stability and control of the article throughout the period in which said manoeuvre is being performed.

Another purpose of the present invention is to provide a steering device, which is capable of working in an optimum manner even in currently marketed sports articles, without any limitation whatsoever as far as the number and the characteristics and features of the supporting and sliding members thereof are concerned. In particular, the steering device of the invention must be capable of working in an optimum manner in those articles that are provided with wheels as supporting and sliding members having a curved tread thereof, such as for instance in-line roller skates and scooters.

A further, equally important purpose of the present invention is to provide a steering device at competitive costs, which is in addition capable of being manufactured with the use of existing techniques and equipments.

According to the present invention, these object and purposes, as well as further purposes that will be apparent in the following description, are reached in a steering device for sports articles adapted to slide on a supporting surface by means of a plurality of supporting and sliding elements provided in an in-line arrangement, i.e. aligned along a same longitudinal axis, which incorporates the characteristics as recited in the appended Claim 1.

Anyway, features and advantages of the steering device according to the present invention will be more readily understood from the description of a particular, although not sole embodiment that is given below by way of non-limiting example with reference to the accompanying drawings, in which:

FIG. 1 is a side elevational, partially cross-sectional view of a steering device according to the present invention, as applied to an in-line roller-skate;

FIG. 2 is an exploded view, similar to the one appearing in FIG. 1, of the steering device according to the present invention.

FIG. 3 is a cross-sectional view of the steering device illustrated in FIG. 1, as viewed along the sectional plane III-III;

FIG. 4 is an exploded view of the cross-sectional representation of FIG. 3;

FIG. 5 is a bottom plan view of the roller skate illustrated in FIG. 1 in a first operating position thereof,

FIG. 6 is a bottom plan view of the roller skate illustrated in FIG. 1 in a second operating position thereof.

FIG. 7 shows a second embodiment of a steering device according to the present invention;

FIG. 8 shows a third embodiment of a steering device according to the present invention;

FIG. 9 shows a fourth embodiment of a steering device according to the present invention;

FIG. 10 shows a fifth embodiment of a steering device according to the present invention;

FIG. 10a shows a particular of the steering device of FIG. 10;

FIG. 11 is a bottom plan view of the wheel arrangement for the steering device of FIG. 10;

With reference to the above-listed Figures, the reference numeral 1 is used there to generally indicate a sports article adapted to slide on a supporting surface 2 by means of a plurality of supporting and sliding elements 3 aligned along a same longitudinal axis 4 or, in other words, provided in an in-line arrangement. In the particular embodiment illustrated in the Figures, the sports article is constituted by a skate 1 provided with at least three, and preferably four, wheels 3 that perform as the elements on which the skate is capable of supporting and sliding on a supporting surface formed by the ground 2; the wheels 3 are provided in an in-line arrangement and have a curved tread.

The skate 1 comprises a chassis 5 supporting in a known manner a footwear (not shown) provided thereupon, wherein at least a carriage 6a provided to support at least a pair of wheels 3 is associated to said chassis. This carriage 6a is associated to the chassis 5 in a manner as to be able to swing about an axis 7 inclined at an angle α relative to the ground 2 and lying substantially on the longitudinal median plane of the chassis as defined by the longitudinal axis 4.

With reference to the particular embodiment illustrated in the accompanying Figures, the chassis 5 has, approximately in correspondence to at least an end portion 8a thereof, a support member 9 provided with a first through-hole 10 and having at least a surface 9a inclined relative to the ground 2 by an angle β, which is preferably complementary to the angle α.

The carriage 6a has an arm 11 for the connection thereof to the support member 9, said arm being provided with a second through-hole 12 and having a surface 11a facing towards and counter-shaped, i.e. shaped complementarily, to the surface 9a. From this arm 11 there extend, on respective, mutually opposite sides, a first and a second fork 13, 14, each one of which pivotally supports a wheel 3 in correspondence to respective support axes 25, 26.

Extending through the first hole 10 and the second hole 12 there are connecting means, such as a threaded pin 15 or the like, for pivotally connecting the carriage 6a to the support member 9; the pin 15 is locked with the aid of appropriate locking means, such as a lock-nut or bolt 16.

The configuration of the carriage 6a and the support member 9, along with the arrangement of the related connection, is such as to ensure that the supporting and sliding elements, i.e. the two wheels 3 in this case, are supported by the carriage 6a in a manner that is substantially parallel to the supporting surface 2, which is formed by the ground in this case, on opposite sides with respect to the pivoting centre 27 of the carriage 6a relative to the chassis 5, as defined by the pin 15 and the second hole 12.

Appropriate elastic means 17, 18 interacting with the arm 11 are provided to elastically contrast the swinging motion of the carriage 6a with respect to the chassis 5. According to a preferred embodiment illustrated in FIGS. 3 and 4, the above-cited elastic means 17, 18 are housed within respective accommodations 19, 20 provided in the support member 9; they are further provided with respective apertures 21, 22 for the insertion therethrough of respective projections 23, 24 extending from the arm 11. In this manner, the accommodation of these elastic contrasting means 17, 18 turns out as being extremely compact and fully contained within the carriage 6a. In an advantageous manner, the degree of elasticity of said elastic means 17, 18 may be varied with the help of appropriate adjustment means or by simply replacing said elastic means 17, 18 with other means having a different elasticity rating as required.

The swinging axis 7 preferably extends approximately in correspondence to or above the support axis 25 of the supporting and sliding element 3 situated in the neighbourhood of the middle portion of the chassis 5.

The description given above refers to a steering device comprising a single carriage 6a. However, a preferred embodiment of the device, as illustrated in FIGS. 1, 5 and 6, calls for the utilization of two carriages 6a, 6b provided in an arrangement in which they symmetrically oppose each other, approximately in correspondence to the end portions 8a, 8b of the chassis 5, wherein each such carriage supports a pair of wheels 3.

The operation of the device is as follows: from the position that is held when the article, i.e. the skate in this case, follows a rectilinear path, in which the supporting and sliding elements are arranged aligned along the longitudinal axis 4 (FIG. 5), a change in direction is obtained by the effect of a sidewise inclination that the user imparts to the article; this motion causes the carriages 6a, 6b to rotate with respect to the chassis 5 in opposite directions about the swinging axis 7 against the action of the elastic means 17, 18, as this is best shown in FIG. 6. In this manner, the supporting and sliding elements 3 are able to arrange themselves along two incident axes that can be assimilated to an arc of a circle owing to the contiguousness of the same supporting and sliding elements 3. Such an arrangement makes it possible for the change in direction to be performed in a smooth and continuous manner, thereby enabling the user to maintain the stability and the control of the article throughout the phase during which such manoeuvre, i.e. the change in direction, is being performed.

Fully apparent from the above description is therefore the ability of the in-line roller-skate according to the present invention to effectively reach the afore cited aims and advantages: in fact, the steering device according to the present invention is reliable and safe in use, while enabling the user to perform even sudden, abrupt changes of direction in a smooth and continuous manner and maintaining full stability and control of the article throughout the phase during which such manoeuvre, i.e. the change in direction, is being performed. These advantages are obtained by the user through a simple inclination of the article in the direction in which he/she wishes to turn: this in fact brings about such an interplay of forces on the carriages 6a, 6b as to cause them to rotate, i.e. swing in a mutually opposite manner about the axis 7 against the action of the elastic means 17, 18: the front carriage 6a rotates in the direction of curvature, while the rear carriage 6b rotates in the opposite direction, in such a manner as to approximately define an arc of a circle, as shown in FIG. 6, which substantially corresponds to the arc of the curve that must be performed. Furthermore, the conformation of the wheels 3 provided with a curved tread 28, which allows the article to incline, i.e. to move into its inclined posture as required in view of enabling the steering device according to the present invention to properly operate, allows for the same steering device to be used practically on all sports articles that are currently marketed with the afore-indicated features.

It shall be appreciated that the above-described steering device may of course be the subject of a number of modifications and variants, also in connection with different applications, without departing from the scope of the present invention.

For example, the embodiments shown in FIGS. 7, 8 and 9 refer to a steering device as described above applied to a sports article, such as a roller skate 101, 201, 301, having a plurality of supporting and sliding elements, such as wheels 103, 203, 303, of different size. Hereinafter the description shall refer to a steering device according to the present invention as applied to an in-line roller skate, but it is understood that the steering device can be evenly applied to any sports article having a plurality of supporting and sliding elements of a different size arranged along a line.

More in detail, FIG. 7 shows an arrangement for the supporting and sliding elements comprising four wheels 103 wherein the front wheel 103a and the third wheel 103c are smaller in diameter than the second wheel 103b and the rear wheel 103d; the wheels 103a and 103b are supported on respective first support axis 125a and 126a by a first carriage 106a which is associated to a chassis 105 in a manner as to be able to swing about a first axis 107a as already described above; similarly, the wheels 103c and 103d are supported on respective second support axis 125b and 126b by a second carriage 106b associated to the chassis 105 so as to be able to swing about a second axis 107b having an inclination in respect to a supporting surface 102 which is opposite to the inclination of the first axis 107a. In order to allow the wheels 103a and 103b, as well as the wheels 103c and 103d, to contact the supporting surface 102 along the same plane, the line 130a connecting the first support axis 125a and 126a is slightly inclined in respect to the supporting surface 102; due to the particular wheel arrangement of this embodiment, the line 130b connecting the second support axis 125b and 126b is inclined along the same direction of line 130a. This specific wheel arrangement achieves an increase in the acceleration of the skate, especially when starting, thanks to the provision of the smaller front wheel 103a which rotates at a higher rotational speed and it has a lower inertia.

The third embodiment shown in FIG. 8 refer to a different arrangement for the wheels, wherein the central wheels 203b and 203c are smaller in diameter that the front wheel 203a and the rear wheel 203d; in this case, the lines 230a and 230b connecting, respectively, the first support axis 225a, 226a and the second support axis 225b, 226b are oppositely inclined in respect to the supporting surface 202 in order to allow all the wheels to contact the supporting surface 202 along the same plane. This arrangement provides the skater with a more stable balance: in fact, the centre of balance, which is determined by the height of the ball of the foot in respect to the ground, can be lowered since the smaller second wheel 203b located under the ball of the foot allows to lower the height of the chassis 205, and in particular the height of the sole plate which supports the sole of the footwear, thus getting the foot closer to the ground.

FIG. 9 shows a further arrangement for the wheels 303, providing the front wheels 303a and 303b of a smaller diameter than the rear wheels 303c and 303d; with this arrangement the lines 330a and 330b connecting, respectively, the first support axis 325a, 326a of the front wheels 303a, 303b, and the second support axis 325b, 326b of the rear wheels 303c, 303d, are arranged parallel to the supporting surface 302 but mutually located at different heights in respect to said supporting surface 302. This wheel arrangement enhances the characteristics of acceleration of the skate, thanks to the provision of the smaller wheel 303a at the front of the skate as explained above, as well as of stability thanks to the second smaller wheel 303b located under the ball of the foot which allows to lower the centre of balance of the skater; in addition, the larger wheels 303c and 303d at the rear have an influence on the efficiency of the skate, allowing to maintain the speed acquired through the higher acceleration at a substantially constant value with a relative low power supply from the skater.

A further embodiment is shown in FIGS. 10 to 11, wherein a skate 401 comprises a first carriage 406a and a second carriage 406b each supporting at least a pair of wheels 403; the first carriage 406a and the second carriage 406b are associated to a chassis 405 approximately in correspondence of its end portions 408a, 408b, in a manner as to be able to swing about respective axis 407a and 407b arranged at an angle of 90° relative to the ground 402 and lying substantially on the longitudinal median plane of the chassis 405 as defined by the longitudinal axis 404.

With reference to FIG. 10a, the following description refers to the second carriage 406b, however it evenly applies to the first carriage 406a. The second carriage 406b has an arm 411 provided with a through-hole 412 for connection to the chassis 405, this latter being provided with a corresponding through-hole 410; connecting means, such as a threaded pin 415 or the like, extends through the holes 410 and 412 for pivotally connecting the carriage 406b to the chassis 405; the pin 415 is locked with the aid of appropriate locking means, such as a lock-nut or bolt 416.

From the arms 411 there extend, on respective, mutually opposite sides, first and second forks 413, 414 pivotally supporting the wheels 403 in correspondence to respective support axes 425, 426.

The wheels 403 have a different size: in fact the wheels 403a arranged at the front and at the rear of the skate 401 have a width which is smaller than that of the wheels 403b arranged in a central portion of the chassis 405.

Appropriate elastic means 417 interacting with the arms 411 are provided to elastically contrast the swinging motion of the first carriage 406a and of the second carriage 406b in respect to the chassis 5.

The wheel arrangement of FIGS. 10 to 11 allows to achieve a change of direction thanks to the larger width of the central wheels 403b: in fact, when the skater inclines the skate laterally toward the ground, the larger central wheels 403b remain the only wheels in contact with the ground, thus forcing the swingable carriages 406a and 406b to swing about the vertical axis 407a and 407b along opposite directions so that an ideal line of curvature is achieved.

It is understood that the materials used to manufacture the device of the present invention, as well as the shapes and the sizing thereof, may each time be selected so as to more appropriately meet the particular requirements or suit the particular application, without departing from the scope of the present invention.