GB2152393A

GB2152393A - Toy vehicle

Info

Publication number: GB2152393A
Application number: GB08432503A
Authority: GB
Inventors: Kwai-Kau Law
Original assignee: LAW KWAI KAU
Current assignee: LAW KWAI KAU
Priority date: 1984-01-04
Filing date: 1984-12-21
Publication date: 1985-08-07
Also published as: GB8432503D0; GB8400087D0

Abstract

A toy vehicle has a periodically operating mechanism 20-24 for raising front wheel 9 clear of a running surface. Motor 11 drives rear wheel 18, but rear wheel 19 is freely rotatable, so that when wheel 9 is raised the vehicle turns. <IMAGE>

Description

SPECIFICATION Motorised toy vehicle The invention relates to a motorised toy vehicle.

According to the present invention there is provided a toy vehicle comprising: at least one front wheel; two rear wheels; a motor; and a drive coupling the motor to drive one of the rear wheels; the other rear wheel being free to rotate independently of the drive, and the vehicle being so arranged as to be capable of remaining tilted with the front wheel or wheels clear of the running surface on which the vehicle runs, the driven wheel then being effective to spin the vehicle about the free rear wheel.

In the preferred embodiment of the invention the vehicle has three wheels and is combined with an automatic, momentary lifting mechanism.

The invention will further be described with reference to the accompanying drawings, of which: Figure 1 is a schematic pian view of a toy vehicle in accordance with the invention; Figure 2 is a side elevation of the drive and lifting mechanism of the vehicle of Figure 1; Figure 3 is a rear elevation of the mechanism of Figure 2; and Figure 4 is a perspective view.

With reference to Figures 1, 2, 3 and 4, the vehicle is a motor cycle which consists of three main assemblies; a body 8-10, a drive mechanism 11-19 and an automatic lifting mechanism 20-25. A single front wheel 9 is freely pivoted between forks 8 of the body 10.

The cycle is propelled forward by means of an electric motor 11 which drive a gear meshing with a cog 13. Cog 13 is fixed to a cog 14 which meshes with a cog 15 which is bound securely to an axle 17. The axle is also bound securely to wheel 18.

However, wheel 19 is free to rotate with respect to axle 17. Hence the motor drives only wheel 18 and a suitable choice of electrical input to the motor will cause the motor cycle to move forwards.

With the front wheel on the running surface (for example the floor or a table surface) the motor cycle is driven in a straight line.

Also provided for the cycle is an automatic lifting mechanism 20-25. Gear 16, which is fixed with respect to cog 15, drives cog 20 to which is attached a cam 21. Cam 21 makes a periodical sliding contact with a plate 22. At one end of the rod 23 is a small, freely pivoted wheel which, in this mode of operation, remains in contact with the running surface whilst the other end of the rod is attached to the body of the cycle 10 at a pivot 25. The plate 22 is attached to rod 23 and is located in a suitable position between the wheel and the pivot 25.

Motion of the cycle in a forward direction, therefore, causes cog 20 and cam 21 to rotate. When the cam 21 touches plate 22 its motion is impeded and it attempts to force the plate, and thus the wheel 24, downwards. Wheel 24, however, is already in contact with the surface on which the cycle is travelling and hence the body of the cycle is lifted in a clockwise direction (as seen in Figure 2) about pivot 25. The front wheel 9 of the cycle remains airbourne whilst the cam 21 is in sliding contact with plate 22. When the plate no longer impedes the motion of the cam, the body of twe cycle falls back and the front wheel drops to the ground. Therefore, whilst the cycle is in motion the front wheel makes periodical lifts into the air.

It will be appreciated that, in this particular mode of operation, there are three primary ways in which the motion of the cycle can be varied: the speed of the cycle, the frequency of the automatic lifts and the height of the lifts. The principles involved are simple and the subsequent modification of the cycle would be simple to a person skilled in such motionised assemblies.

The cycle speed could be adjusted by changing the motor 11 or by varying the gear ratios of the assembly 12-15 or by a combination of both. It must be stressed, however, that a certain "threshold" torque is required to produce the lifting action and care is necessary to ensure this.

The frequency of the automatic lifts can be adjusted by varying the gear ratios between cogs 16 and 20 whilst the simplest method of obtaining the height of the lifts is by changing the length of the cam 21. This, however, may also alter the duration of the lifts although the duration can be altered by changing the orientation of the plate 22 in such a way as to reduce the hinderance of the cam's motion.

An important feature of the cycle is that it can be tilted to a position where it will remain with front wheel 9 and the lifting wheel 24 free of the running surface. In this condition the driven wheel 18 will drive around the free wheel 19 producing a type of spinning motion. The said tilting of the cycle into such a position has two effects. Firstly more weight is applied to the rear wheels and thus a greater reaction exists between the rear wheels and the surface which leads to an increased component of friction at these interfaces. Secondly, the frictional restriction of the front wheel against sideways movement has been removed. The overall effect is that the cycle is driven to turn about the wheel 19. Therefore, the cycle turns when the front wheel lifts.

It must be noted that the choice of rear wheels that is driven by the motor is arbitrary and similar results would be obtained if the opposite rear wheel were driven.

1. A toy vehicle comprising: at least one front wheel; two rear wheels; a motor; and a drive coupling the motor to drive one of the rear wheels; the other rear wheel being free to rotate independently of the drive, and the vehicle being so arranged as to be capable of remaining tilted with the front wheel or wheels clear of the running surface on which the vehicle runs, the driven wheel then being effective to spin the vehicle about the free rear wheel.

2. A toy vehicle as claimed in claim 1 wherein there is provided a mechanism for automatically lifting the front wheel or wheels intermittently.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Motorised toy vehicle The invention relates to a motorised toy vehicle. According to the present invention there is provided a toy vehicle comprising: at least one front wheel; two rear wheels; a motor; and a drive coupling the motor to drive one of the rear wheels; the other rear wheel being free to rotate independently of the drive, and the vehicle being so arranged as to be capable of remaining tilted with the front wheel or wheels clear of the running surface on which the vehicle runs, the driven wheel then being effective to spin the vehicle about the free rear wheel. In the preferred embodiment of the invention the vehicle has three wheels and is combined with an automatic, momentary lifting mechanism. The invention will further be described with reference to the accompanying drawings, of which: Figure 1 is a schematic pian view of a toy vehicle in accordance with the invention; Figure 2 is a side elevation of the drive and lifting mechanism of the vehicle of Figure 1; Figure 3 is a rear elevation of the mechanism of Figure 2; and Figure 4 is a perspective view. With reference to Figures 1, 2, 3 and 4, the vehicle is a motor cycle which consists of three main assemblies; a body 8-10, a drive mechanism 11-19 and an automatic lifting mechanism 20-25. A single front wheel 9 is freely pivoted between forks 8 of the body 10. The cycle is propelled forward by means of an electric motor 11 which drive a gear meshing with a cog 13. Cog 13 is fixed to a cog 14 which meshes with a cog 15 which is bound securely to an axle 17. The axle is also bound securely to wheel 18. However, wheel 19 is free to rotate with respect to axle 17. Hence the motor drives only wheel 18 and a suitable choice of electrical input to the motor will cause the motor cycle to move forwards. With the front wheel on the running surface (for example the floor or a table surface) the motor cycle is driven in a straight line. Also provided for the cycle is an automatic lifting mechanism 20-25. Gear 16, which is fixed with respect to cog 15, drives cog 20 to which is attached a cam 21. Cam 21 makes a periodical sliding contact with a plate 22. At one end of the rod 23 is a small, freely pivoted wheel which, in this mode of operation, remains in contact with the running surface whilst the other end of the rod is attached to the body of the cycle 10 at a pivot 25. The plate 22 is attached to rod 23 and is located in a suitable position between the wheel and the pivot 25. Motion of the cycle in a forward direction, therefore, causes cog 20 and cam 21 to rotate. When the cam 21 touches plate 22 its motion is impeded and it attempts to force the plate, and thus the wheel 24, downwards. Wheel 24, however, is already in contact with the surface on which the cycle is travelling and hence the body of the cycle is lifted in a clockwise direction (as seen in Figure 2) about pivot 25. The front wheel 9 of the cycle remains airbourne whilst the cam 21 is in sliding contact with plate 22. When the plate no longer impedes the motion of the cam, the body of twe cycle falls back and the front wheel drops to the ground. Therefore, whilst the cycle is in motion the front wheel makes periodical lifts into the air. It will be appreciated that, in this particular mode of operation, there are three primary ways in which the motion of the cycle can be varied: the speed of the cycle, the frequency of the automatic lifts and the height of the lifts. The principles involved are simple and the subsequent modification of the cycle would be simple to a person skilled in such motionised assemblies. The cycle speed could be adjusted by changing the motor 11 or by varying the gear ratios of the assembly 12-15 or by a combination of both. It must be stressed, however, that a certain "threshold" torque is required to produce the lifting action and care is necessary to ensure this. The frequency of the automatic lifts can be adjusted by varying the gear ratios between cogs 16 and 20 whilst the simplest method of obtaining the height of the lifts is by changing the length of the cam 21. This, however, may also alter the duration of the lifts although the duration can be altered by changing the orientation of the plate 22 in such a way as to reduce the hinderance of the cam's motion. An important feature of the cycle is that it can be tilted to a position where it will remain with front wheel 9 and the lifting wheel 24 free of the running surface. In this condition the driven wheel 18 will drive around the free wheel 19 producing a type of spinning motion. The said tilting of the cycle into such a position has two effects. Firstly more weight is applied to the rear wheels and thus a greater reaction exists between the rear wheels and the surface which leads to an increased component of friction at these interfaces. Secondly, the frictional restriction of the front wheel against sideways movement has been removed. The overall effect is that the cycle is driven to turn about the wheel 19. Therefore, the cycle turns when the front wheel lifts. It must be noted that the choice of rear wheels that is driven by the motor is arbitrary and similar results would be obtained if the opposite rear wheel were driven. CLAIMS

3. A toy vehicle as claimed in claim 1 wherein the lifting mechanism comprises a cam drive by the motor and effective to exert an intermittent downward force against the running surface.

4. A toy vehicle as claimed in claim 3 wherein the downward force is exerted through the intermediary of an arm pivoted at one end of the vehicle and running at the other end on the running surface.

5. A toy vehicle as claimed in any of the preceding claims which is a tricycle, there being only one wheel at the front.

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