GB2225250A - A toy vehicle - Google Patents

Abstract

A toy vehicle, when halted by an obstruction, turns and proceeds in another direction. The vehicle includes an axle 7 to which wheel 8 is secured and to which wheel 10 is clutched through pawl/ratchet 11/9. An inertia wheel motor in a cage 16 normally drives the axle 7 through gear 18. The cage 16 is weighted at 26, 27 to normally hang in the position shown. When an obstruction prevents rotation of axle 7, the cage 16 rotates and/or oscillates around the axle, this movement together with the action of pawl/ratchet 11/9 causing the vehicle to turn away from the obstruction. <IMAGE>

Description

This invention relates to a toy and in particular to a toy vehicle.

According to a first aspect of the present invention there is provided a toy vehicle with a motor for driving the vehicle in a first direction, direction changing means being provided so that in use when the vehicle is travelling in said first direction and is prevented from further movement in that direction the vehicle will turn and then proceed in another direction different from said first direction.

According to a second aspect of the present invention there is provided a toy vehicle having a motor, and an axle arranged to be driven by the motor, two wheels being carried by the axle for driving the toy, a ratchet and pawl device being arranged to transmit drive from said axle to one of said wheels and adapted in use operatively to disengage the wheel from the axle when the said wheel is subject to an axle-torque resisting force greater than a predetermined value, the other wheel being permanently operatively connected to the axle, thereby in use to turn the vehicle when said one wheel is operatively disengaged.

According to a third aspect of the present invention there is provided a toy vehicle which vehicle includes a generally horizontal axle bearing two wheels, a first of said wheels being fixedly connected to said axle for rotation therewith in both a first and a second sense of rotation, and a second of said wheels being operatively connected to said axle for fixed rotation with the axle in said second sense of rotation only, and for frictional rotation with said axle in said first sense, a relatively massive motor device operatively connected to said axle by gearing to drive the axle in said first sense of rotation thereby to drive the vehicle in a first direction, the motor device being eccentrically mounted with respect to the axis of the axle and, in a rest position, being dependent therefrom, and the motor device being free to undergo planetary rotation around the axle in said second sense of rotation when said axle is prevented by an obstacle from rotating in said first sense being constrained against planetary rotation around the axle in said first sense of rotation but being constrained against planetary rotation around the axle in said first sense of rotation, the arrangement being such that when the motor device moves in planetary motion in said second sense about the axle and the centre of gravity of the device passes over top dead centre with respect to the axle, the motor device will be accelerated by the Earth's gravity in its planetary motion about the axle and will pass under and beyond bottom dead centre with respect to the axle, a resultant pendulum-like return of the motor device to its rest position giving the axle an impetus in said first sense of rotation which impetus drives the first wheel in rotation in said first sense but which does not drive the second wheel in rotation due to slippage between the rotating axle and the second wheel, thereby to cause the vehicle to turn to avoid a said obstacle.

Preferably the motor is supported in a cage mounted on the axle and is arranged to drive the axle in rotation by means of a plurality of gear wheels.

Other objects, advantages and preferred features of the invention will be apparent from the following description of an embodiment of a toy vehicle in accordance with the present invention, and/or from a contemplation of the claims appended hereto.

An embodiment of a toy vehicle will now be described by way of example only, by reference to the accompanying drawings, in which: Figure 1 is a crude diagramatic side elevation of an embodiment of a toy vehicle according to the present invention.

Figure 2 is a diagramatic rear elevation of the rear axle assembly of the toy vehicle of Figure 1; and Figure 3 is a diagramatic perspective view of part of the mechanism of the toy vehicle of Figures 1 and 2.

Referring to the drawings, a toy vehicle 1 comprises an upper body 2 and a lower body 3. The lower body 3 is a plastics moulding and supports for free rotation a front axle (not shown) having a pair of front wheels one of which is shown at 4. The lower body 3 also provides a pair of journals 5 for supporting a rear axle assembly 6 of the vehicle. The rear axle assembly 6 is shown in some detail in Figure 2 and comprises an axle 7. One end of axle 7 bears a road wheel 8 fixedly mounted thereupon for rotation with the axle 7. The other end of axle 7 bears a concentrically mounted ratchet wheel 9 and a road wheel 10 which is mounted for rotation on axle 7.

Wheel 10 includes a pawl 11 pivotally mounted on a pivot pin 12 and biassed by means of a spring 13 into engagement with ratchet wheel 9.

Mounted centrally of the axle 7 for fixed rotation therewith is a ratchet wheel 14. Ratchet teeth 15 are provided about a portion of the circumference of ratchet wheel 14. Mounted on ratchet wheel 14 is a cage 16. Cage 16 and ratchet wheel 14 support between them a flywheel 17 which is operatively connected to a gear wheel 18 mounted on axle 7 via a train of gears 19, 20, 21, 22, 23, 24, 25.

Also mounted on cage 16 is a pair of relatively massive weights 26, 27 which serve to bias the flywheel, gear train and cage assembly to a lowermost position beneath the axle 7.

Journal led in a forward part of the lower body 3 is a transverse shaft 28. Fixedly mounted on shaft 28 is an arm 29 including a stop surface 30. The arm 29 bears a pin 31 and a spring 32 extends between pin 31 and a pin 33 on lower body 3 to bias the arm 29 downwardly onto a transverse stop wall 34 on lower body 3. The shaft 28 also bears a pawl arm 34A so located in lower body 3 as to engage with the ratchet teeth 15 of ratchet wheel 14.

Upper body 2 is formed to have an appearance pleasing to a child, with superstructure features such as an engine compartment, a driving cabin and a driver (not shown). At the rear of upper body 2 there is a projection arranged to look like an air-dam or spoiler 35. Mounted within this air-dam or spoiler 35 is a counterweight (not shown).

In use the toy vehicle operates as follows.

A user holding the toy vehicle spins up the flywheel 17 by running the road wheels 8, 10 along a floor surface. Rotation of the wheels 8, 10 is transmitted to the -flywheel through axle 7 and through the gear train 18-25. Upon release of the toy vehicle on a floor the flywheel 17 will now impart drive to both of wheels 8, 10 via the same gear train 18-25 and axle 7. The weight of the motor/cage assembly, combined with the interaction of pawl arm 34A with ratchet teeth 15, is sufficient to keep the motor/cage assembly at a lowermost point beneath axle 7.

When the vehicle hits an obstacle, e.g. a wall, wheel 8 can no longer rotate. The axle 7 is thus also prevented from rotating. The effect is that continued rotation of fly wheel 17 now causes the motor/cage assembly to rotate in planetary fashion about axle 7. Because rotation is in an opposite sense to the interengagement of pawl arm 34A and ratchet teeth 15 there is no constraint against such rotation.

When the motor/cage assembly passes over top dead centre with respect to the axle 7, the motor/cage assembly will be accelerated downwardly under the influence of the Earth's gravity. (The transfer of the weight of the motor/cage assembly to the rear of axle 7 when added to that of the counterweight will cause the front of the vehicle to lift up, i.e. to do a "wheelie"). As the thus-accelerated motor/cage assembly passes beyond bottom dead centre, it will either continue to be driven in planetary fashion about the axle if the flywheel 17 is rotating quickly enough, or the flywheel 17 will have insufficient energy to carry the motor/cage assembly once more over top dead centre. In the latter case, because the circumference of ratchet wheel 14 is only partly provided with ratchet teeth 15 (Figure 3), pawl arm 34A does not engage operatively with any ratchet teeth 15 at this point.The result is that the motor/cage assembly will then swing backwards to pass once more beneath bottom dead centre relative to axle 7. The effect of this backward swing is to impart extra torque to axle 7. Since wheel 8 is still obstructed by the obstacle which the vehicle hit, it still cannot rotate. The additional torque however is sufficient to overcome the engagement between pawl 11 of wheel 10 and ratchet wheel 9 on axle 7. Thus, the effect is to cause the axle to move in a horizontal plane about a vertical pivot axis passing through the point of contact of wheel 10 with the ground. Thus the vehicle will turn. Continued oscillation back and forth of the motor/cage assembly beneath axle 7 will cause further turning movement of the vehicle until the vehicle has turned away from the obstacle and is free once again to move.

The stop surface 30 of the spring-loaded arm 29 is arranged to protrude into the path of rotation of a stop member 36 provided on the cage 16. The interengagement of stop surface 30 with stop member 36 is such as to prevent the motor cage assembly from continuing in planetary motion if there is insufficient flywheel energy to overcome the spring bias of arm 29. The interengagement of stop surface 30 and stop member 36 can also serve to provide a second rest position for the motor/cage assembly.

Normally the motor/cage assembly will simply depend beneath axle 7. However the aforesaid interaction can cause the motor/cage assembly to be located at an intermediate point with its centre of gravity already forward of axle 7. The effect, when combined with the aforementioned "wheel ie" phenomenon, is such that when the wheel 8 meets an obstacle, the subsequent movement in rotation of the motor/cage assembly will produce a vehicle-turning effect more quickly.

It is to be noted that even when the speed of the flywheel is such as to cause the motor/cage assembly to undergo several complete orbits about axle 7, the changes in position of the centre of gravity of the motor/cage assembly will themselves impart a back and forth motion to the vehicle which again can be sufficient to overcome the frictional engagement between pawl 11 of wheel 10 and ratchet wheel 9 of axle 7 thus to provide a vehicle-turning effect.

In a preferred embodiment of a vehicle according to the present invention other pleasing features may be driven by the flywheel 17. Thus, for example, a lever arm (not shown) may be caused to move by means of one or more radial projections (not shown) on axle 7. Movement of such a lever arm can be arranged to cause movement of further devices such as, for example, intermittent vertical movement of an "engine exhaust pipe", or intermittent movement of "front suspension members" of the vehicle.

The toy of this invention is amusing, ingenious and provides a pleasing motion when it strikes an obstacle.

It is to be understood that the invention may be performed otherwise than as has been particularly described. It is intended to include within the scope of the present invention all changes and modifications which would be apparent to one skilled in the art.

Claims (8)

1. A toy vehicle having a motor, and an axle arranged to be driven by the motor, two wheels being carried by the axle for driving the toy, a ratchet and pawl device being arranged to transmit drive from said axle to one of said wheels and adapted in use operatively to disengage the wheel from the axle when the said wheel is subject to an axle-torque resisting force greater than a predetermined value, the other wheel being permanently operatively connected to the axle, thereby in use to turn the vehicle when said one wheel is operatively disengaged.

2. A toy vehicle with a motor for driving the vehicle in a first direction, direction changing means being provided so that in use when the vehicle is travelling in said first direction and is prevented from further movement in that direction the vehicle will turn and then proceed in another direction different from said first direction.

3. A toy vehicle which vehicle includes a generally horizontal axle bearing two wheels, a first of said wheels being fixedly connected to said axle for rotation therewith in both a first and a second sense of rotation, and a second of said wheels being operatively connected to said axle for fixed rotation with the axle in said second sense of rotation only, and for frictional rotation with said axle in said first sense, a relatively massive motor device operatively connected to said axle by gearing to drive the axle in said first sense of rotation thereby to drive the vehicle in a first direction, the motor device being eccentrically mounted with respect to the axis of the axle and, in a rest position, being dependent therefrom, and the motor device being free to undergo planetary rotation around the axle in said second sense of rotation when said axle is prevented by an obstacle from rotating in said first sense being constrained against planetary rotation around the axle in said first sense of rotation, but being constrained against planetary rotation around the axle in said first sense of rotation, the arrangement being such that when the motor device moves in planetary motion in said second sense about the axle and the centre of gravity of the device passes over top dead centre with respect to the axle, the motor device will be accelerated by the Earth's gravity in its planetary motion about the axle and will pass under and beyond bottom dead centre with respect to the axle, a resultant pendulum-like return of the motor device to its rest position giving the axle an impetus in said first sense of rotation which impetus drives the first wheel in rotation in said first sense but which does not drive the second wheel in rotation due to slippage between the rotating axle and the second wheel, thereby to cause the vehicle to turn to avoid a said obstacle.

4. A toy vehicle according to claim 3, wherein the motor is supported in a cage mounted on the axle and is arranged to drive the axle in rotation by means of a plurality of gear wheels.

5. A toy vehicle, according to any one of the preceeding claims, wherein the motor is a friction flywheel motor.

6. A toy vehicle, substantially as hereinbefore described.

7. A toy vehicle, substantially as hereinbefore described, with reference to the accompanying drawings.

8. The features hereinbefore disclosed, or their equivalents, in any novel selection.