GB2158401A - Skateboard - Google Patents

Abstract

A manually powered skateboard includes a rear wheel axle 40 on which is mounted a transmission wheel 36 connected to a rear hub 37 through a one way clutch 38. A drive input wheel 29 drives the transmission wheel 36 and is mounted on auxiliary shaft 26 which is parallel to the rear wheel axle 40. A cable 33 is wound on the drive input wheel 29 and is pullable by a user to rotate the drive wheel 29 and in turn the transmission wheel 36. A spring 34 acts on the drive wheel 29 to wind up the cable 33 thereon. A brake member 41 cooperates with the drive input wheel 29 through a clutch 25 selectively to rotate with the drive wheel 29 to effect braking action on the rim 42 of the rear wheel 39. The clutch 25 is actuated by a brake pedal (not shown) disposed at the front of the skateboard platform. Thus the braking action is effected only by clutching the drive input wheel 29 to the brake member 41. The concurrent operations of pressing on the brake pedal to engage the clutch and pulling the cable 33 to turn the wheel 29, enables the user to keep his balance when the skateboard is braked, and the forward tilting of the user's body is counterbalanced by the backward pulling of the cable. <IMAGE>

Description

SPECIFICATION Skateboard The present invention relates to a skateboard which is manually powered.

Unpowered skateboards rely for their movement on the user pushing against the ground with one foot, and/or the force of gravity when the skateboard is used on a sloping surface. In U.K. Patent Application No.

8324770 invented by this inventor, a skateboard is disclosed which can be driven by the user on a level surface, i.e. without the aid of gravity, with both of the user's feet on the board. In the above-referenced application, a skateboard is designed to have a manually powered drive means for driven wheel thereof, comprising a drive wheel coaxial with a rear hub member mounting said driven wheel and connected thereto through a oneway clutch, a flexible tension element wound on said drive wheel and pullable by a user to rotate the drive wheel and thereby to drive said driven wheel, and spring means acting on the drive wheel to wind up the tension element. Adjacent said hub member, a brake shoe is disposed for braking said hub member.A brake operating lever is pivotally mounted under the skateboard platform at the front thereof and has one end operatively connected to said brake shoe and another end extending above the front end of the platform and formed as a pedal engageable by a user's foot. Such a skateboard has the disadvantage that whenever braking is needed, the pressing action of the user's foot on the pedal located at the far front end of the platform undesirably causes the user's body to tilt forward. In particular, when the skateboard is abruptly braked the user is liable to slip off due to the difficulty of keeping the body balanced.

Therefore, an improvment on the known manually powered skateboard is attempted.

It is an object of the present invention to provide a skateboard which is safer to the user when braking action is actuated.

According to the invention there is provided a skateboard having manually powered drive means for a driven wheel thereof, comprising a transmission wheel coaxial with said driven wheel and connected thereto through a oneway clutch, a drive input wheel arranged to drive said transmisson wheel, a flexible tension element wound on said drive input wheel and pullable by a user to rotate the drive input wheel. thereby to drive said transmission wheel and through the one-way clutch said driven wheel, spring means acting on the drive input wheel to wind up the tension element, and brake means arranged to cooperate through clutch means with said drive input wheel so as to selectively to rotate therewith to effect braking action on said driven wheel.

Prererably said driven is a rear wheel of the skateboard and is mounted on a ear hub member mounted on a rear wheel axle which also mounts the said transmisson wheel.

Preferably said drive input wheel is mounted on an auxiliary shaft which is parallel to said rear wheel axle.

Preferably said braking action is effected on the rim of said rear wheel.

Preferably said brake means includes a brake member fixedly mounted on said auxiliary shaft to engage with the rim of said rear wheel of effect braking action.

Preferably said auxiliary shaft is of noncircular cross section, and said drive input wheel is rotatably mounted thereon by a bearing member.

Preferably said clutch means includes a clutch ring mounted on said auxiliary shaft and arranged to be axially shiftable thereon, said clutch ring having a clutch plate for engagement with a side surface of said drive input wheel.

An embodiment of the invention will now be described by way of example and with reference to the accompaying drawings, in which: Figure 1 is a schematic side view in partial section of a skateboard according to the present invention; Figure 2 is an underneath plan view in partial section of the rear region of the skateboard; Figure 3 is a rear vertical view in partial section of the rear region of the skateboard shown in Fig. 2.

As shown in Fig. 1, the skateboard includes a pair of front wheels 1 and a pair of rear wheels 2. In Fig. 1, only one of each pair is depicted. A front frame 4 rotatably mounting a front wheel axle 3 is steered by a steering shaft 5. The steering shaft 5 extends rotatably through a platform 6 and pivotally mounts a steering plate 7. In this embodiment the steering plate 7 also acts as a brake pedal 7. The rear portion of the brake pedal 7 is biassed upwardly be a spring 8. The front edge of the front portion of the brake pedal 7 is formed as a hook 9 for engaging an end of a brake operating lever 10 which extends downwardly through the platform 6. It will be noted that the braking action is effected by means of a clutch mechanism. Thus, some elements incorporated in the braking operation will be designated in terms of clutch function.A clutch operating cable 11 has one end connected to the brake operating lever 10 at the front of the skateboard, and the other end connected to a clutch operating lever 20 at the rear of the skateboard as shown in Fig. 2.

Pressing action on the rear portion of the brake pedal 7 is thereby transmitted to pull the clutch operating lever 20. The clutch operating cable 11 is preferably guided by a pulley 1 2 disposed underneath the platform 6.

As shown in Figs. 2 and 3, an ellipse shaped cam plate 21 is pivotally mounted on a cam shaft 22. A helical spring 23 is sleeved on the cam shaft 22 and has one end connected to the cam plate 21 and the other end connected to the underside of the platform 6, thereby biassing the cam plate 21 against the rotation caused by actuating the clutch operation lever 20. Two stud members 24 are symmetrically disposed either side of the centre of the ellipse shaped cam plate 21 and on the major axis of the ellipse. A pair of clutch rings 25 are mounted on an auxiliary shaft 26 of square cross section and are free to move only in the axial direction of the auxiliary shaft 26. Each clutch ring 25 includes two spaced annular plates 27 coaxial with a clutch plate 28.Each stud member 24 is disposed in the space between the two annular plates 27 for shifting each clutch ring 25 towards the respective drive input wheel 29. A plurality of protrusions 31 and recesses are separately disposed annularly on the opposing faces of the clutch plate 28 and the drive input wheel 29 for engagement and disengagement of these two members. The mechanism for driving the skateboard is shown in Figs. 2 and 3 and is described as follows. The drive input wheel 29 is rotatably mounted on the drive shaft 26 by a ball bearing 32 and is driven by the user pulling a cable 33 wound on the drive input wheel 29.

A coil spring 34 is disposed coaxially of the drive input wheel, having one end secured to a rear frame 35 and the other end secured to the drive input wheel 29. The coil spring 34 acts on the drive input wheel 29 to wind up the cable 33 thereon when the user's pull on the cable is released. On the rim of the drive input wheel 29 a toothed portion is provided for meshing with a corresponding toothed portion on the rim of a transmission wheel 36 which is connected to a rear hub member 37 through a one-way clutch 38. As a result the rotation of the drive input wheel 29 caused the user pulling the cable 33 is transmitted through the toothed portion to the transmission wheel 36. By means of the one-way clutch 38, drive may only be transmitted in one direction from the transmission wheel 36 to the rear hub member 37 so as to drive the rear wheel 39 forwards.The rear hub member 37, the transmisson wheel 36 and the rear wheel 39 are coaxially mounted on a rear wheel axle 40 which is disposed in parallel relationship with the auxiliary shaft 26. A brake member 41 is fixedly mounted on the auxiliary shaft 26 adjacent the rim 42 of the rear wheel 39 so as to be movable into braking engagement therewith.

The braking operation of the skateboard is effected as follows. When the user's foot presses down on the rear portion of the brake pedal 7, the cable 11 is pulled and the cam plate 21 is pivotted to a position as shown in phantom line. This causes the stud member 24 to shift the annular plates 27 towards the drive input wheel 29. As the clutch plate engages the adjacent side wall of the drive input wheel 29, the clutch ring 25 and the drive shaft 26 are fixed to rotate with the drive input wheel. Thus, if the cable 33 is now pulled by the user's hand to rotate the drive wheel 29, brake member 41 is rotated into contact with the rim of the rear wheel to effect the braking action. In these circumstances, forward leaning of the user's body caused by pressing on the brake pedal at the front of the skateboard is counterbalanced by pulling on the cable 33 to rotate the drive input wheel 29. As a consequence, the gravity of the body can easily be kept in a desired balance position.

Claims (18)

1. A skateboard having manually powered drive means for a driven wheel thereof, comprising a transmission wheel coaxial with said driven wheel and connected thereto through a one-way clutch, a drive input wheel arranged to drive said transmission wheel, a flexible tension element wound on said drive input wheel and pullable by a user to rotate the drive input wheel, thereby to drive said transmission wheel and through the one-way clutch said driven wheel, spring means acting on the drive input wheel to wind up the tension element, and brake means arranged to cooperate through clutch means with said drive input wheel so as selectively to rotate therewith to effect braking action on said driven wheel.

2. A skateboard as claimed in claim 1, wherein said driven wheel is a rear wheel of the skateboard and is mounted on a rear hub member mounted on a rear wheel axle which also mounts the said transmission wheel.

3. A skateboard as claimed in claim 2, wherein said drive input wheel is mounted on an auxiliary shaft which is parallel to said rear axle.

4. A skateboard as claimed in claim 3, wherein said braking action is effected on the rim of said rear wheel.

5. A skateboard as claimed in claim 4, wherein said brake means include a brake member fixedly mounted on said auxiliary shaft to engage with the rim of said rear wheel to effect braking action.

6. A skateboard as claimed in claim 5, wherein said auxiliary shaft is of non-circular cross section, and said drive input wheel is rotatably mounted thereon by a bearing member.

7. A skateboard as claimed in claim 6, wherein said clutch means includes a clutch ring mounted on said auxiliary shaft and arranged to be axially shiftable thereon, said clutch ring having a clutch plate for engag ment with a side surface of said drive input wheel.

8. A skateboard as claimed in claim 7, wherein a plurality of protrusions are annu larly disposed on said clutch plate and a corresponding plurality of recesses are annu larly disposed on said side surface of said drive wheel, the protrusions and recesses meshing together when the clutch is engaged.

9. A skateboard as claimed in claim 8, wherein a cam plate is pivotally disposed under the skateboared platform for shifting said clutch ring in the axial direction.

10. A skateboard as claimed in claim 9, wherein said clutch ring includes two spaced annular plates coaxial with said clutch plate, and said cam plate has a stud member disposed between said two plates so that when said cam plate is pivoted, said stud member shifts either one of said annular plates to engage or disengage said clutch plate with or from said said drive input wheel.

11. A skateboard as claimed in claim 10, wherein spring means is arranged between said cam plate and said platform for biassing said clutch plate away from said drive input wheel.

1 2. A skateboard as claimed in claim 11, wherein said cam plate has a clutch operating lever for pivotting the cam plate to actuate the braking action.

1 3. A skateboard as claimed in claim 12, wherein a clutch operating tension element is provided for pulling said clutch operating lever.

1 4. A skateboard as claimed in claim 13, wherein a pulley is disposed under a front portion of said skateboard platform for guiding said clutch operating tension element upwardly of said platform.

1 5. A skateboard as claimed in claim 14, wherein a brake pedal is further pivotally disposed above a front region of said skateboard platform in operative connection with said clutch operating tension element, said brake pedal being operable by the user's foot.

16. A skateboard as claimed in claim 15, wherein said clutch opeating tension element is pulled by depressing a rear portion of said brake pedal toward said platform.

1 7. A skateboard as claimed in claim 16, wherein the rear portion of said brake pedal is spring biassed upwardly.

18. A skateboard as claimed in claim 17, wherein said brake pedal is a steering plate and is connected to a front wheel axle by a steering shaft extending rotatably through said platform.

1 9. A skateboard substantially as hereinbefore described with reference to the accompanying drawings.