NL2023422B1 - Four-wheeled pedal go-kart, and use thereof - Google Patents

Abstract

The invention relates to a four-wheeled pedal go-kart comprising a go-kart frame and a driven rear wheel shaft rotatably suspended in the frame. The rear wheel shaft is provided with a rear sprocket rotationally coupled thereto in both a forward and a rearward rotational direction. The go-kart further comprises a drive shaft rotatably suspended in the frame by means of bearings, which is drivable by means of two pedals. The go-kart comprises a chain or a belt for transferring rotational movement of the front sprocket to the rear sprocket and vice versa. The drive shaft includes a bush rotatably suspended in the frame by the bearings, and a crankshaft extending through the bush. A front sprocket is rotationally coupled to the bush in both a forward and a rearward rotational direction. The crankshaft defines two ends provided with a respective crank provided with a respective one of the two pedals. The drive shaft is arranged to be brought from a first state in which the bush is rotationally coupled to the crankshaft into a second state in which the bush is uncoupled from the crankshaft such as to allow the bush to freely rotate about the crankshaft.

Description

P122502NL00 Title: Four-wheeled pedal go-kart, and use thereof The invention relates to a four-wheeled pedal go-kart, in particular a relatively compact pedal go-kart arranged for relatively young children of about two to five years old, more in particular toddlers.

A pedal go-kart or so-called pedal kart or so-called pedal car is a four-wheeled human-powered vehicle which usually is used as an outdoor toy. Pedal go-karts are usually intended to be used by children. Although some of these known pedal go-karts are arranged and intended for somewhat older children, nowadays there are also pedal go-karts intended and arranged for relatively young children of about two to five years old, more 1n particular toddlers, whom, in contrast to such somewhat older children, are not really able to play with a go-kart independently.

Such pedal go-karts for relatively young children such as toddlers are known. For example, the Dutch company BERG Toys sells such a pedal go-kart under the name BERG Buzzy, which is a relatively compact go-kart arranged for a child aged two to five years. This known BERG Buzzy go-kart comprises a frame in which a front wheel shaft and a rear wheel shaft are rotatably suspended. Each of said wheel shafts supports two respective wheels, i.e. each of said wheel shafts supports a left wheel and a right wheel. At least one wheel supported by the rear wheel shaft is rotatably coupled to said rear wheel shaft, and the other rear wheel may be freely rotatable about the rear wheel shaft, such that the two rear wheels do not need to rotate with the same rotational speed thereby enabling to facilitate making turns with the go-kart. The rear wheel shaft is provided with a rear sprocket rotatably coupled to said rear wheel shaft. By means of a drive chain, said rear sprocket is connected to a front sprocket which is provided on, and rotatably coupled to, a crank shaft rotatably suspended in the frame. Said crankshaft can be driven by means of two pedals each provided at a respective one of two cranks provided on the crankshaft. The transmission between the pedals and the rear wheel rotatably coupled to the rear shaft is formed by a so-called fixed-gear drivetrain which is free of a freewheel mechanism. As a result, when the toddler, or other relatively young child, pedals, the wheel rotatably coupled to the rear shaft is driven such as to ride forwards. On the other hand, when, for instance in case an adult is pushing the go-kart, said rear wheel is made to rotate, said rear wheel will drive the pedal cranks. This is contrary to a freewheel mechanism that includes an internal ratcheting mechanism and that prevents that the rear wheel will drive the pedal cranks, but which will allow that the pedal cranks drive the rear wheel. Such fixed-gear drivetrain may be advantageously utilized in a pedal go-kart for a toddler or other relatively young child, because when a parent or a guardian pushes the child on the pedal go-kart, the rear wheel driving the pedals will help the child to get started. Moreover, when the go-kart has got started and has some momentum, said fixed-gear drivetrain helps the child riding the go- kart to continue pedaling, as a result of which the pedal go-kart is easy to ride by relatively young children. Furthermore, the fixed-gear drivetrain also enables to ride the go-kart rearwards. It is noted that the fixed-gear drivetrain causes that the child cannot keep his legs still while riding, as when the child stops pedaling and keeps his legs still, the rear wheel will stop rotating and causes the go-kart to come to a halt in slightly slipping manner. It is noted that this can be a huge advantage, as toddlers or other relatively young children with Little experience will usually instinctively stop pedaling when they want to stop the go-kart, but are usually not capable of actively operating a brake when a situation occurs in which they should swiftly stop the go-kart.

It will be appreciated by the skilled person that, for instance as a toddler or other young child riding a pedal go-kart may become tired relatively soon, or may be relatively stubborn when he doesn’t feel like pedaling anymore, it can easily happen that the child and his parent(s) are stranded somewhere, and that it then can be relatively hard for the parent(s) to get the child and the go-kart back home, for instance as it may be a relatively heavy effort to carry both the child and the go-kart at the same time.

It is an object of the present disclosure to provide an alternative four-wheeled pedal go-kart, in particular an alternative pedal go-kart which counteracts at least one disadvantage of a prior art pedal go-kart at least partly. More in particular, it can be an object of the present disclosure to provide a pedal go-kart that may help an adult to move both the pedal go-kart and a toddler or other relatively young child when the child does not feel like pedaling the go-kart himself (anymore). Thereto, it can be desirable that an adult can pull or push the drive-kart, especially by means of a pushrod, which may be arranged more or less just like one used with a tricycle for toddlers or other relatively young children of for instance about two to four years old. However, the applicant found that it is not sufficient to simply add a pushrod to a conventional pedal go-kart arranged for relatively young children such as the known BERG Buzzy go-kart, because such a relatively compact and relatively light-weighted pedal go-kart which is provided with a fixed-gear drivetrain in order to facilitate a toddler or other relatively young child, of for instance only two years old, is arranged such that the pedals will keep rotating when said pedal go-kart is pushed forwards. This may not only be annoying to the relatively young child seated on the go-kart, but may even be dangerous and may, for instance therefore, be forbidden by local regulations or legislations.

The present disclosure provides for a four-wheeled pedal go-kart, comprising a go-kart frame; a driven rear wheel shaft rotatably suspended in the frame, the driven rear wheel shaft being provided with a rear sprocket rotationally coupled to said rear wheel shaft in both a forward and a rearward rotational direction; a drive shaft rotatably suspended in the frame by means of bearings, the drive shaft being drivable by means of two pedals, and the drive shaft being provided with a front sprocket; and a chain or a belt for transferring rotational movement of the front sprocket to the rear sprocket and vice versa, wherein the drive shaft includes a sleeve or a so-called bush rotatably suspended in the frame by means of the bearings, and the front sprocket is rotationally coupled to said bush in both a forward and a rearward rotational direction, wherein the drive shaft further includes a crankshaft extending through the bush, said crankshaft defining two ends, each of which is provided with a crank provided with a respective one of the two pedals, and wherein the drive shaft is arranged to be brought from a first state in which the bush is rotationally coupled to the crankshaft into a second state in which the bush is uncoupled from the crankshaft such as to allow the bush to freely rotate about the crankshaft.

By arranging the drive shaft such as to be brought from the first state in which the bush is rotationally coupled to the crankshaft into a second state in which the bush is uncoupled from the crankshaft such as to allow the bush to freely rotate about the crankshaft, a pedal go-kart that includes said drive shaft can be brought from a first mode, especially a pedal mode, in which the pedal go-kart can enjoy the above-mentioned advantages of a fixed-gear drivetrain into a second mode, especially a push and/or pull mode of the go-kart, in which pedals of the go-kart can be kept still and are not driven by the rear wheel when an adult pushes or pulls the go-kart.

By arranging the pedal go-kart such that the bush of the drive shaft, which bush is provided with the front sprocket, is rotatably suspended in the frame by means of the bearings, portions of forces exerted on the pedal go-kart by pushing it forwards, which portions of forces may be transmitted to the front sprocket, may be dissipated via the bush and the bearings to the frame, in particular in such a manner that substantially no part of such portions of forces will be transmitted to the pedals. For instance therefore, it may be highly advantageous that the drive shaft, which includes the bush rotatably suspended in the frame by means of the bearings, further includes the crankshaft extending through said bush.

In the second mode, which in particular can form a push and/or pull mode of the go-kart, chain tension which can work on the bush may 5 thus be dissipated via the bearings into the frame. Therefore, the crankshaft can then be kept substantially unloaded. This can be highly advantageous, for instance as it may counteract relatively well that the pedals start turning along when the go-kart is pushed forward by a grown-up.

It will be appreciated that the crankshaft and the bush may be substantially aligned such that they may extend substantially coaxially with each other.

Further, it will be appreciated that the bush may extend substantially coaxially with the bearings.

The front sprocket, which may, at least in embodiments, be considered as part of the drive shaft, may extend substantially coaxially with the bush and/or the crankshaft.

The drive shaft may be provided with a clutch for rotationally coupling and decoupling the bush and the crankshaft to each other and from each other, respectively.

Preferably, the clutch includes a first engagement member associated with the bush and a second engagement member associated with the crankshaft, wherein said second engagement member can cooperate with the first engagement member such as to substantially couple the first engagement member to the second engagement member in rotational direction.

By arranging the pedal go-kart such that the bearings by means of which the bush of the drive shaft is rotatably suspended in the frame include a first bearing and a second bearing, wherein said first bearing and said second bearing are offset from each other in an axial direction of the drive shaft, and wherein, seen in said axial direction of the drive shaft, the first engagement member and the second engagement member, at least in the first state of the drive shaft, are located between said first bearing and said second bearing, it can be facilitated that, at least in the first state of the drive shaft when the bush is rotationally coupled to the crankshaft, at least portions of forces that are exerted on the crankshaft by means of pedaling can be transmitted from the crankshaft to the front sprocket at a location between said two bearings.

It may be particularly advantageous when these forces, or at least portions thereof, are transmitted at a location, which in the axial direction of the crankshaft, is located relatively close to said front sprocket.

Thereto, the pedal go-kart may be arranged such that, in the first state of the drive shaft, the first engagement member and the second engagement member can be coupled in rotational direction at a location, which in the axial direction of the crankshaft, is located between said two bearings and relatively close to said front sprocket, for instance not being offset more than 3 cm, preferably no more than 2 cm, such as for instance at most 1 cm, from said front sprocket.

Preferably, the pedal go-kart can include a control, for instance a control knob, for operating at least one of the engagement members of the clutch, wherein, seen in the axial direction of the drive shaft, at least in the first state of the drive shaft, a first one of the two bearings is located between the control and the respective one of the engagement members of the clutch, such that, at least in the first state of the drive shaft, said control and said respective engagement member are located at opposite lateral sides of said respective one of the two bearings.

Further, the present disclosure also relates to the use of such a pedal go-kart, which, although it may be used in a home setting, may for instance also be used at a creche, kindergarten or primary school.

Advantageous embodiments according to the present disclosure are described in the appended claims.

By way of non-limiting examples only, an embodiment of the present invention will now be described with reference to the accompanying figures in which: Fig. 1 shows a schematic perspective view of an embodiment of a four-wheeled pedal go-kart according to an aspect of the invention; Fig. 2 schematically shows a partly cut-a-way perspective view of the go-kart of Fig. 1 in which its drivetrain is visible relatively well; Fig. 3 shows a schematic exploded view of a drive shaft forming part of the drivetrain shown in Fig. 2 of the go-kart shown in Fig. 1; and Fig. 4 shows a schematic perspective view of a detail of the drivetrain shown in Figs. 2 and 3 in which a control knob is partly cut away.

It is noted that the figures show merely a preferred embodiment of a pedal go-kart according to an aspect of the invention. Further it is noted that, in the figures, the same or similar reference signs or numbers refer to equal or corresponding parts.

Figure 1 shows an embodiment of a four-wheeled pedal go-kart 1, which may be ridden by rotatably driving pedals 15. Here, said go-kart 1 is formed as a completely assembled pedal go-kart which for instance may be provided with go-kart parts such as one or more of: four wheels 2; a steering arrangement 91, which may comprise a handlebar 92 or a steering wheel; a seat 94; a brake 95, in particular a hand brake 95; and further go-kart parts. However, in alternative embodiments, the four-wheeled pedal go-kart 1 may for instance be a go-kart chassis, which for instance may not yet be provided with its wheels 2 and/or may not yet be provided with one or more other go-kart parts 94 of the completely assembled go-kart.

The four-wheeled pedal go-kart 1 may be intended and/or arranged to be used by a toddler or other relatively young child, for instance a child of about two to five years old, for which parental supervision may be necessary. Thereto, the go-kart may be relatively small and/or relatively light-weighted, such as to facilitate that a relatively small and/or relatively young child, of for instance only about 2 years old and/or only about 90 cm tall and/or only about 12 kg heavy, may be able to drive the go-kart 1 by means of pedaling.

Further, the go-kart 1, which may be intended and/or arranged for use by a toddler or other relatively small child, may be arranged to be used in at least two modes, in particular at least a first mode, in particular a so-called pedal mode, in which a child seated on the go-kart 1 can pedal and a second mode in which the go-kart can be pushed or pulled by an adult when a toddler or other child is seated on said go-kart. As will be elucidated below, the pedal go-kart 1 may be arranged such that it can be brought from the so-called pedal mode. in which the pedal go-kart 1 may be adapted to function as a go-kart having a fixed-gear drivetrain, into the second mode in which the pedals 15 can be kept still when an adult pushes or pulls the pedal go-kart 1.

In the here shown embodiment, the go-kart 1 comprises a push handle 50 such that said pedal go-kart 1 is arranged for enabling an adult to push the pedal go-kart 1. For example, the push handle 50, or so-called push bar, push rod or adult steer 50, may be removably attachable to a frame 12 of the go-kart 1, for instance in order to have it removed in the pedal mode.

Additionally or alternatively, the push handle 50 may be adjustable, for instance in order to adjust its height and/or the extent to which it sticks out to the rear.

In order to facilitate an adult to push the go-kart 1 in its second mode relatively conveniently, the go-kart 1 may in embodiments comprise a steering lock 93 for temporarily locking the steering arrangement 91 in a certain position. For instance as the four-wheeled pedal go-kart 1 may be intended and/or arranged for relatively small children such as toddlers, the go-kart 1 may have dimensions that are relatively small. For example, the go-kart 1, excluding a push rod or push handle 50 if any, may have a length L1 not exceeding 120 cm, preferably not exceeding 100 cm, in particular between 65 cm and 100 cm, more in particular between 70 cm and 95 cm, yet more in particular between 75 cm and 90 cm, such as for instance between 80 cm and 85 cm.

Additionally or alternatively, the pedal go-kart 1 may have a relatively low weight. Preferably, the pedal go-kart 1 may have a weight which is relatively low with respect to the weight of the relatively young child riding the go-kart 1 during use, in particular in the pedal mode. Preferably, the weight of the pedal go-kart 1 may be not substantially exceeding the weight of the child, and may preferably be at most 80% of the weight of the child, more preferably at most 75% of the weight of the child, or even less. In embodiments, the go-kart 1, excluding the push rod or push handle 50 if any, may have a weight of at most 15 kg, preferably at most 12 kg, more preferably at most 10, such as about 8 kg or about 7 kg, or even less. By arranging that the go-kart 1 has a relatively low weight, it can not only be facilitated that the toddler or other relatively small child can pedal relatively easily, but it may also be counteracted that the inertia of the moving go-kart will be relatively large, as a result of which such relatively low weight can facilitate enabling that the child may be able to stop the moving go-kart, in particular in a relatively convenient manner.

As can be seen in Fig. 1, the pedal go-kart 1 comprises a go-kart frame 12. The go-kart 1 further comprises a driven rear wheel shaft 13 rotatably suspended in the frame 12, which may be provided with two wheels 2. In embodiments, such as in the embodiment shown here, said driven rear wheel shaft 13, may form a rear axis 13 of the go-kart 1 which can be provided with two rear wheels 2A. Further, the frame 12 may be provided with two rotatably suspended front wheels 2, 2B which may be steerable by means of a steering arrangement 91.

As can be seen in Fig. 2, the driven rear wheel shaft 13 is provided with a rear sprocket 19. Said rear sprocket 19 is rotationally coupled to said rear wheel shaft 13 in both a forward D1 and a rearward D2 rotational direction, and is preferably fixedly mounted to said rear wheel shaft 13. The go-kart 1 further comprises a drive shaft 14 which is rotatably suspended in the frame 12 by means of bearings 20, in particular rolling-element bearings 20 or so-called rolling bearings 20, such as for example ball bearings or roller bearings. The drive shaft 14 is drivable by means of the two pedals 15, in particular foot pedals 15.

It will be appreciated that the drive shaft 14 can be formed as an assembly of parts. The drive shaft 14 includes a crankshaft 4 which defines two ends, each of which is provided with a respective crank 17, i.e. a left crank and a right crank, respectively. Here, as can be seen in Fig. 3, the cranks 17 and the crankshaft 4 are formed as integral portions 17, 4 of the same part. Each of the left crank and the right crank is provided with a respective one of the two pedals 15.

As can be seen relatively well in Figs. 3 and 4, the drive shaft 14 also includes a sleeve 3 or a so-called bush 3 which is rotatably suspended in the frame 12 by means of the bearings 20. The crankshaft 4 extends through said bush 3 or so-called bushing 3. For instance in order to facilitate assembly of the drive shaft 14, the bushing 3 or so-called sleeve 3 may comprise multiple parts 31, 32 which may be mounted such as together form the sleeve 3. Here, the bush 3 is formed from two complementary parts 31, 32, but the bush 3 may alternatively for instance also be made out of more than two parts.

Further, the drive shaft 14 is provided with a front sprocket 16. Said front sprocket 16 is rotationally coupled to said bush 3 or so-called sleeve 3 in both a forward D1’ and a rearward D2’ rotational direction. For example, the front sprocket 16 may be mounted to a flange 34 which radially protrudes from the bush 3. In embodiments, the front sprocket 16,

which may be mounted to multiple parts 31, 32 of the bush 3, may be used to mount these multiple parts 31, 32 with respect to each other. Additionally or alternatively, the bush 3 may be arranged for mounting a front sprocket 16 thereto.

For example, the bush 3, in particular multiple parts 31, 32 thereof, may be provided with at least one stop 315, e.g. defined at least partly by a flange 34, against which at least one stop 315 a side surface 161 of said front sprocket 16 may rest.

Additionally or alternatively, the bush 3, in particular its parts 31, 32, may define a support 314 for facilitating to substantially align the center lines of the front sprocket 16 and the bush 3 with respect to each other. Said support 314 may define a substantially cylindrically surface 314 having a diameter which may correspond with, and which then preferably can be slightly smaller than, an inner diameter of a central opening in the front sprocket 16. When mounting said sprocket 16, a surface 164 defined by said central opening can then be placed on or over the support 314. Additionally or alternatively, the bush 3, in particular its parts 31, 32, may comprise one or more holes 349, for instance provided with internal screw thread, which may preferably be located at the flange 34 if any. The front sprocket 16 may be provided with one or more corresponding holes 169, such that said front sprocket 16 can be mounted to the bush 3 by means of fasteners 9, in particular screws 9 or bolts extending through said corresponding holes 169, 349. The pedal go-kart 1 further comprises a chain 18 or a belt for transferring rotational movement of the front sprocket 16 to the rear sprocket 19 and vice versa. Further, the drive shaft 14 is arranged such that it can be brought in a first state in which the bush 3 is rotationally coupled to the crankshaft 4 in both a forward rotational direction D1’ and a rearward rotational direction D2’. The go-kart 1 is arranged such that the drive shaft 14 can be brought from the first state into a second state in which the bush 3 1s uncoupled from the crankshaft 4. In the second state, the bush 3 can thus freely rotate about the crankshaft 4. This means that when an adult, such as a parent or a guardian, pushes the go-kart 1 or pulls the go-kart 1, the pedals 15 can be kept still and are not driven when a rear wheel 2A’ rotationally coupled to the rear wheel shaft 13 is rotated as a result of pushing or pulling the pedal go-kart 1. It is noted that preferably at least one rear wheel 2A’ supported by the rear wheel shaft 13 is rotatably coupled to said rear wheel shaft, and that the other rear wheel 2A may preferably be freely rotatable about the rear wheel shaft 13, such that the two rear wheels do not need to rotate with the same rotational speed thereby enabling to facilitate making turns with the go-kart 1.

In the first state of the go-kart 1, in which the bush 3 is rotationally coupled to the crankshaft 4 in both a forward rotational direction D1’ and a rearward rotational direction D2’, the transmission between the pedals 15 and the rear wheel 2A’ rotatably coupled to the rear shaft 13 can then be formed like a so-called fixed-gear drivetrain which is then free of a freewheel mechanism. As a result, when the toddler, or other relatively young child, pedals when the go-kart 1 is in said first state, the wheel 2A’ rotatably coupled to the rear shaft 13 is driven such as to ride forwards. On the other hand, when, for instance in case an adult is pushing the go-kart 1, said rear wheel 2A’ is made to rotate when the go-kart 1 is in its first state, said rear wheel 2A’ will drive the pedal cranks 17 and thus the pedals 15. As a result, when a parent or a guardian then pushes the toddler or other relatively small child seated on the pedal go-kart 1, the rear wheel 2A’ driving the pedals 15 will help the child to get started. Moreover, when the go-kart has got started and has some momentum, said drivetrain acting as a fixed gear drivetrain in the first state of the go-kart 1 helps the child riding the go-kart 1 to continue pedaling, as a result of which the pedal go-kart 1 can be relatively easy to ride by relatively young children. Furthermore, the drivetrain also enables to ride the go-kart rearwards by rearward pedaling in the first state of the go-kart. Moreover, the drivetrain acting as a fixed gear drivetrain in the first state of the go-kart 1, can facilitate that the go-kart 1 can be stopped by the child by simply holding still the pedals 15 by just simply stopping pedaling.

The drive shaft 14, which includes the crankshaft 4 and the bush 3 that can be releasably coupled to each other in two opposite rotational directions D1’, D2, can include a clutch 5, which is be arranged for rotationally coupling the bush 3 and the crankshaft 4 to each other and is also arranged for rotationally decoupling them from each other.

Thereto, the clutch 5 may for instance include a first engagement member 61 which is associated with the bush 3. In Fig. 3, an embodiment of such first engagement member 61 is shown, which is formed such as to include a slide 61, but which may be formed differently in alternative embodiments. The clutch 5 may further include a second engagement member 41 which is associated with the crankshaft 4. Said second engagement member 41 can cooperate with the first engagement member 61 such as to substantially couple the first engagement member 61 to the second engagement member 41 in rotational direction, in particular in both rotationally directions D1’, D2’ of the drive shaft 14.

In embodiments, at least one of the two engagement members 61, 41 of the clutch 5, and preferably the first engagement member 61 which preferably is associated with the bush 3, may be movable along the drive shaft 14, for instance in a linear direction D4, D5 and/or substantially in the axial direction D3 of the drive shaft 14. The other one of the two engagement members 61, 41 of the clutch 5, preferably the second engagement member 41 which preferably is associated with the crankshaft 4, may be fixed with respect to the part 4, 3 with which it is associated, and may preferably, such as is shown in the exemplary embodiment of Fig. 3, be rotationally fixed to the crankshaft 4. Said second engagement member 41 may comprise an opening 42 or so-called recess 42 arranged for receiving at least a part of the first engagement member 61, which preferably can be associated with the bush 3. Said opening 42 can for example be formed as a blind hole, a through hole, a slit 42 or other indentation which does not need to be limited at all its peripheral sides, and can for instance be open at its outer side.

As noted above, the first engagement member 61, which preferably can be associated with the bush 3, may for example be formed such as to include a slide 61. In embodiments, the clutch 5 may include a coupling member 6 that includes the first engagement member 61. The bush 3 can then be provided with a sliding channel 33, which for instance may be formed as a slit, slot or groove.

Said sliding channel 33 is arranged for allowing at least a part 61, 62 of the coupling member 6 to slide there through at least partly, preferably in a manner in which the coupling member 6 is guided by guiding surfaces 331, 332 defined by the bush 3. Although the sliding channel 33 can extend substantially in the axial direction D3 of the drive shaft 14, this is not necessary, and actually the sliding channel 33 does not need to be straight either, as it for instance may be curved and can then for instance guide a curved coupling member, or as it for instance can guide a coupling member 6 which at least partly is flexible to some extent and can thus adapt to some extent to the shape of such sliding channel.

Besides, it is noted that although the coupling member 6 may be formed as an integral element comprising multiple integrally formed parts 61, 62, 63, the coupling member 6 may alternatively be formed out of separate parts.

The clutch 5 can be arranged such that, at least in the first state of the drive shaft 14, the coupling member 6 is substantially prevented from rotating with respect to the bush 3 about the crankshaft 4.

With respect to the bearings 20, by means of which the bush 3 of the drive shaft 14 can be rotatably suspended in the frame 12, it is noted that these bearings 20 may preferably include a first bearing 21 and a second bearing 22. Preferably, said first bearing 21 and said second bearing 22 can be offset from each other in an axial direction D3 of the drive shaft

14. Advantageously, the pedal go-kart 1 is arranged such that, at least in the first state of the drive shaft 14, the first engagement member 61 and the second engagement member 41 are, when seen in said axial direction D3 of the drive shaft 14, both located between said first bearing 21 and said second bearing 22. In particular, the first bearing 21 may be located at the left-hand side of the said two engagement members 61, 41, whereas the second bearing 22 may be located at the right-hand side of said engagement members 61, 41. As a result, it may be facilitated that, at least in said first state of the drive shaft 14 when the bush 3 is rotationally coupled to the crankshaft 4, at least portions of forces that are exerted on the crankshaft 4 by means of pedaling can be transmitted from the crankshaft 4 to the front sprocket 16 at a location between said two bearings 21, 22. This may be advantageous, for example as such forces, or at least portions thereof, can then be transmitted at a location, which in the axial direction D3 of the crankshaft 4, is located relatively close to said front sprocket 16. It 1s noted that the bush 3, in particular its parts 31, 32, may define a cavity 341 for accommodating the second engagement member 41 which is associated with the crankshaft 4. As can be seen in Fig. 3, the location of said cavity 341 is here, in axial direction D3 of the drive shaft 14, located relatively close to the location 316, here defined by the support 314 and the stop 315, at which the front sprocket 16 is to be mounted. When the clutch 5 is rotationally coupled, in this embodiment by sliding the first engagement member 61 into an opening 42 of the second engagement member 41, the engagement members 61, 41 engage each other at the location at which the second engagement member 41 is located within said cavity 341 formed in the bush 3. In the first state of the drive shaft 14, the first engagement member 61 and the second engagement member 41 can be coupled in rotational direction D1’, D2" at a location, which in the axial direction D3 of the crankshaft 14, is located between the two bearings 21, 22 and which is thus also relatively close to said front sprocket 16. In particular, in said axial direction D3, an offset between a central plane of the front sprocket 16 and a most nearby location at which the engagement members 61, 41 are engaged can be chosen such that said offset is at most 4 cm, preferably at most 3 cm, such as for instance at most 2 cm.

Preferably, the coupling member 6 may comprise a first part 61 defining the first engagement member 61, which, at least in the first state of the drive shaft 14, and preferably also in its second state, is located between the two bearings 21, 22. The coupling member 6 may then comprise a second part 62 which extends through one 21 of the bearings 20, thereby enabling that the coupling member 6 may be operated at a location which, with respect to said bearing 21, is located at the opposite side than the side at which the first engagement member 61 engages the second engagement member 41 in the first state of the drive shaft 14. Said second part 62 of the coupling member 6 may at least partly extend through the sliding channel 33. In embodiments, such as for instance in the embodiment shown in the figures, see especially Fig. 4, at least a portion of the sliding channel 33 can be open at its top side, in particular at least at a portion 35 of the bush 3 that during use is accommodated within the respective bearing 21. By doing so, it can be enabled that, seen in a radial direction of the crankshaft 4, almost the entire distance between an outer surface 40 of said crankshaft 4 and an inner surface 210 of said bearing 21 can be utilized for allowing the second part 62 of the coupling member 6 to slide through said bearing 21. In other words, the height of said second part 62 can be almost the same as the local wall thickness 36 of said portion 35 of the bush 3 located within said bearing 21. As a result, the local wall thickness 36 of said portion 35 of the bush 3 can be kept relatively small, thereby enabling that the inner diameter of an opening defined by said bearing 21 can be relatively small, whereas the diameter of the cross-section of the crankshaft 4 can be relatively large. As a result, such an at least partly open sliding channel 33 can thus enable using a relatively thick and strong crankshaft 4, and can simultaneously still enable using a relatively small and compact bearing 21, without compromising the height, and thus the strength, of the second part 62 of the coupling member 6 to a relatively large extent.

Further, said first part 61 of the coupling member 6, or another part of the coupling member 6, may protrude from a second part 62, for example in a direction transverse to a direction D5 in which at the coupling member 6 can be slidable, and may then form a stop, which for instance can cooperate with the bush 3, in particular to prevent that the coupling member 6 can be pulled out of the bush 3.

Additionally or alternatively, the pedal go-kart 1 may, at least in embodiments, include a control 7 for operating at least one 61 of the engagement members 61, 41 of the clutch 5. In particular, when seen in the axial direction D3 of the drive shaft 14, at least in the first state of the drive shaft 14, a first one 21 of the two bearings 20 can then be located between the control 7 and the respective one 61 of the engagement members 61, 41 of the clutch 5, such that, at least in the first state of the drive shaft 14, said control 7 and said respective engagement member 61 are located at opposite lateral sides of said first one 21 of the two bearings 21, 22. The control 7, in particular a rotary control knob 7, can thus be located at or near a lateral end of the drive shaft 14, and may for instance preferably be located substantially outside of a chain guard 99.

For instance like the bush 3, the rotary control knob 7 may be formed from two or more than two parts which can be mounted together, for example by means of fasteners 79, such as for instance screws 79 or the like.

This may be advantageous, for example in order to facilitate installing the knob 7, which during use may be located substantially coaxially with the crank shaft 4, around the crank shaft 4, in particular when the crank shaft 4 and the cranks 17, that may extend transverse with respect to the axial direction of the crank shaft 4, are integrally formed.

Said control 7 may for instance be formed as a control switch, a control knob 7, or a control button, and may for instance be arranged to be operated by tilting it, sliding it, rotating it, or pressing it. Advantageously, the go-kart 1, in particular its drive shaft 14, may be arranged such as to translate the motion of the operated control 7 into a desired motion, preferably a substantially linear motion, of the first engagement member 61.

For example, as is the case in the shown embodiment, the control 7 can include and/or be formed as a rotary knob 7 which is rotatable with respect to a central axis A14 of the drive shaft 14, whereas the pedal go-kart 11s then arranged such that at least a part of rotation motion of said rotary knob 7 can be translated to a substantially linear motion of the first engagement member 61 associated with the bush 3. As for instance can be seen in Fig. 3, the control knob 7, which can define a substantially cylindrically shaped cavity 77 for accommodating a respective portion 37 of the bush 3, may thereto be provided with a control element 71 cooperating with the coupling member 6.

Said control element 71, which may move along with the control knob 7 in a rotational direction D1’, D2’ when said knob 7 is rotated about the central axis A14 of the drive shaft 14, may for instance define a hook portion 71 or other portion which can hook behind an engagement portion 63 of the coupling member 6 and which can pull, or can push, the coupling member 6 in a direction D4, D5 in which the first engagement member 61 is pulled, or pushed, away from, or alternatively pulled, or pushed, towards, the second engagement member 41, when said control element is moved in said direction D4, D5. In the here shown embodiment, the control element 71 pulls the first engagement member 61 in an outward direction D5, but the go-kart 1 could be arranged in an alternative manner, for instance such that the control element 71 pulls or pushes the first engagement member 61 in an inward direction D4. With respect to the engagement portion 63 of the coupling member 6, it is noted that it is formed as a flange 63 in the embodiments shown in the figures, but that it could be formed differently in alternative embodiments.

Here, the flange defines a hooking surface 64 behind which the hook portion 71 of the control element 71 can hook, and along which it can slide in the rotational direction D1’, D2’ upon rotation of the control knob 7. Said hooking surface 64 is here extending substantially in a plane transverse to the central axis A14 of the drive shaft 14, such that when the control element 71 moves in an outward direction D5, it pulls the coupling member 6, and thus the first engagement member 61, in an outward direction D5. However, the hooking surface 64 may be designed differently, and may for instance define a run-on surface that is arranged such that when the knob 7 is rotated without moving the knob and/or its hook portion 71 in the outward direction D5 or inward direction D4, the coupling member 6 and thus the first engagement member 61 can still be pulled outwardly, or moved differently in direction D4, D5 substantially along the drive shaft 14. The four-wheeled pedal go-kart 1, in particular the assembly forming the drive shaft 14, may be arranged to move the rotary knob 7, or at least the control element 71, in a direction D5 along the drive shaft 14 upon rotation of said rotatory knob 7 about the central axis A14 of said drive shaft 14. For example, the bush 3 may be provided with a run-on surface 39 for engagingly cooperating with a engaging element 72 associated with the control knob 7. Although said engaging element 72 and the control element 71 may be formed by the same integral part 70, they could alternatively be formed by different parts.

For example, in an alternative embodiment, the control knob’s inner surface defining the substantially cylindrically shaped cavity 77 for accommodating the respective portion 37 of the bush 3 may be provided with screw thread that engages corresponding screw thread provided at an outer surface of said respective portion 37 of the bush 3.

Such as is the case in the here shown embodiment, the first engagement member 61 may be biased in a direction D4 towards the second engagement member 41, in particular by means of one or more spring elements 8, which may form part of the clutch 5, and/or which may be housed in the bush 3, in particular in cavity 38. Although the clutch 5 may thus be biased towards its coupled state, it may alternatively be biased towards its uncoupled state, and may, as a further alternative, not be biased to one of such states at all.

In the here shown embodiment, upon rotation of the control knob 7 in an uncoupling direction D2’, the run-on surface 39 can force the engaging element 72 associated with the control knob 7, against a biasing force provided by the one or more spring elements 8, in an outward direction D5 to some extent, thereby moving said knob 7 and its hook portion 71 defining control element 71 also in said outward direction D5 to some extent. The hook portion 71 pulls the engagement portion 63 of the coupling member 6 along, and the first engagement member 61 associated with the bush 3 is then pulled out of engagement with the second engagement member 41 which is associated with the crankshaft 4, thereby rotationally uncoupling the bush 3 from the crankshaft 4 such as to allow the bush 3 to freely rotate about the crankshaft 4.

In order to counteract that the rotary control knob 7 may unintentionally rotate backwards, in a direction D1’ opposite to the uncoupling direction D2’, the bush 3 can be provided with a hollow, which, when seen in the uncoupling direction D2’, can be located behind the end 390 of run-on surface 39, and which end 390 thus may form a hurdle 390 that may facilitate holding the rotary control knob 7 in a position in which the clutch 5 is uncoupled. Hence, upon uncoupling the clutch 5, the engaging element 72 may get stuck in said hollow into which it can be held by means of the one or more spring elements 8. In order to couple the clutch 5 in order to bring the pedal go-kart 1 back into its pedal mode, in which a child seated on the go-kart 1 can pedal, the rotary control knob 7 can be rotated in a coupling direction D1’ which 1s contrary to the uncoupling direction D2’. The user operating the control knob 7 could then push the control element 71 over the hurdle 390. When the knob 7 is further rotated, e.g. by said user and/or by means of a biasing force exerted by one or more spring elements 8, the knob 7 and its control element 71 move in the inward direction D4, thereby allowing that said one or multiple spring elements 8 can pull or push the first engagement member 61 associated with the bush 3 and the second engagement member 41 associated with the crankshaft 4 towards each other in order to let them engage each other.

In case said engagement members 61, 41 are not coincidentally aligned in the manner shown in Fig. 3 and do not directly couple, they may couple for instance upon a slight rotation of the crankshaft 4, for instance when a child seated on the go-kart 1 starts pedaling, as the one or more spring elements 8 will namely keep pulling or pushing the first engagement member 61 towards the opening 42 formed by the second engagement member 41. Such coupling of the engagement members 61, 41 may also take place upon slight rotation of the bush 3, for instance when an adult pushes the go-kart 1 to get the child started and the bush 3 is driven by the respective rear wheel 2A’ via the rear sprocket 19, chain 18 and front sprocket 16.

It is noted that for the purpose of clarity and a concise description features are described herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features described.

Further, it 1s noted that the invention 1s not restricted to the embodiments described herein.

It will be understood that many variants are possible.

Such variants will be apparent for the person skilled in the art and are considered to lie within the scope of the invention as formulated in the following claims.

Claims (16)

Conclusions A four-wheeled pedal go-kart (1), comprising: a go-kart frame (12); a driven rear wheel axle (13) rotatably suspended in the frame (12), the driven rear wheel axle (13) having a rear sprocket (19) which is rotationally coupled to the rear wheel axle (13) in both a forward (D1) as well as a backward (D2) direction of rotation; a drive shaft (14) rotatably suspended in the frame (12) by means of bearings (20), the drive shaft (14) being drivable by means of two pedals (15), and the drive shaft (14) being provided with a front sprocket (16); and a chain (18) or a belt for transmitting rotational motion from the front sprocket (16) to the rear sprocket (19) and vice versa, the drive shaft (14) comprising a sleeve (3) or a so-called sleeve (3) which rotatably suspended in the frame (12) by means of the bearings (20), and wherein the front sprocket (16) is rotationally coupled to the bush (3) in both a forward (D1) and a reverse (D2) rotational direction , the drive shaft (14) further comprising a crankshaft (4) extending through the bushing (3), the crankshaft (4) defining two ends each of which is provided with a crank (17) provided with a respective one of the two pedals (15), and wherein the drive shaft (14) is arranged to be brought from a first state in which the bush (3) is rotational coupled to the crankshaft (4) to a second state in which the bush (3) is disengaged from the crankshaft (4) to allow the bushing (3) to rotate freely about the crankshaft (4). The pedal go-kart (1) according to claim 1, wherein the drive shaft (14) is provided with a coupling (5) for rotational coupling and uncoupling of the bush (3) and the crankshaft (4) to each other and from each other, respectively. The pedal go-kart (1) according to claim 2, wherein the clutch (5) comprises a first engagement member (61) associated with the sleeve (3) and comprising a second engagement member (41) associated with the crankshaft (4), said second engagement member (41) may cooperate with the first engagement member (61) to substantially couple the first engagement member (61) in rotational direction to the second engagement member (41). The pedal go-kart (1) according to claim 3, wherein the bearings (20) by means of which the bushing (3) of the drive shaft (14) is rotatably suspended in the frame (12) a first bearing (21) and a second bearing ( 22), wherein the first bearing (21) and the second bearing (22) are spaced from each other in an axial direction (D3) from the drive shaft (14), and wherein, viewed in the axial direction (D3) ) of the drive shaft (14), the first engagement member (61) and the second engagement member (41), at least in the first state of the drive shaft (14), between the first bearing (21) and the second bearing (22) located. The pedal go-kart (1) according to claim 4, further comprising an operating element (7) for operating at least one of the engagement members (61, 41) of the coupling (5), wherein, viewed in the axial direction (D3) of the drive shaft (14), at least in the first state of the drive shaft (14), a first one (21) of the two bearings (20) is located between the operating element (7) and the respective one (61 ) of the engagement members (61, 41) of the coupling (5), such that, at least in the first state of the drive shaft (14), the operating element (7) and the respective engagement member (61) on opposite lateral sides of the first one (21) of the two bearings (21, 22) are located. The pedal go-kart (1) according to any one of claims 3-5, wherein at least one of the engagement members (61, 41) of the coupling (5), and then preferably the first engagement member (61) associated with the sleeve (3) ) is movable along the drive shaft (14). The pedal go-kart (1) according to claim 6, wherein the coupling (5) comprises a coupling member (6) comprising the first engagement member (61) associated with the sleeve (3), and wherein the sleeve (3) is provided with a sliding channel (33) configured to allow at least a portion (61, 62) of the coupling member (6) to at least partially slide therethrough. The pedal go-kart (1) according to claim 6 or 7, wherein the coupling (5) is arranged such that, at least in the first state of the drive shaft (14), it is substantially prevented that the coupling member (6) is the bush (3) rotates around the crankshaft (4). Pedal go-kart (1) according to claim 8, wherein the second engaging member (41) associated with the crankshaft (4) is rotationally fixed on the crankshaft (4). A pedal go-kart (1) according to any one of claims 3-9, and in particular according to claim 9, wherein the second engagement member (41) comprises an opening (42) adapted to receive at least a portion of the first engagement member. (61) belonging to the bush (3). A pedal go-kart (1) according to any one of claims 3-10, wherein the first engagement member (61) is biased towards the second engagement member (41), in particular by means of a spring (8). Pedal go-kart (1) according to any one of claims 3-11, in particular according to claim 11, wherein the operating element (7) comprises a rotary knob (7) which is rotatable with respect to a central axis (A14) of the drive shaft ( 14), and wherein the pedal go-kart (1) is arranged such that at least part of the rotational movement of the rotary knob (7) can be converted into a substantially linear movement of the first engaging member (61) associated with the sleeve (3) . The stair go-kart (1) according to claim 12, wherein the stair go-kart (1) is arranged such that the linear movement of the first engagement member (61) is directed in a direction (D5) away from the second engagement member (41). A step go-kart (1) according to any one of the preceding claims, wherein the step go-kart (1) forms a mounted step go-kart. A pedal go-kart (1) according to any preceding claim, further comprising a push handle (50) such that the pedal go-kart (1) is adapted to allow an adult to push the pedal go-kart (1). Use of the four-wheeled pedal go-kart (1) of any of the preceding claims, preferably wherein a toddler or other relatively small child, having a weight exceeding the weight of the pedal go-kart, is seated on the pedal go-kart (1).