GB2103946A - Drive system for toy cars - Google Patents

Abstract

A toy racing car for use on a slotless car racing track has a pair of driven steerable wheels each mounted for king-pin steering and linked by a track rod so that they steer together. Each steering wheel is rotatable about its own axle, rotatably mounted by its respective track arm and has drive gear teeth at the inner end of each axle for driving the axle and its associated steering wheel. The electric drive motor is reversible and a rotatable driven gear is pivotally mounted to be movable between limit positions in which it engages and drives the drive gear teeth of one or other axle of the steering wheels. The driven gear engages with a bevel gear rotated by the drive motor and is coaxially rotatable with the axis of pivoting of the driven gear. The engagement between the driven gear and the bevel gear rotates the driven gear and urges and entrains it towards one or other limit position depending upon the direction of rotation of the motor. <IMAGE>

Description

SPECIFICATION Improvements in drive system for toy cars This invention relates to toy racing car sets. In particular, the invention relates to the drive system for the toy cars in such sets.

Various forms of toy racing car sets are known where an endless track is provided and electrically driven cars under the control of individual operators are raced against one another around the track. There are two main systems. The first is often known as slot racing since the track is provided with a slot and a corresponding pin projects down from underneath the car into the slot and guides the car around its own defined lane of the track. The other system is known by contrast as slotless racing and each car is not constrained to follow a particular lane but can swap from one lane to another. The invention relates specifically to cars for use in the slotless car racing system.

In a slotless car racing system, the car is provided with contacts which bear against continuous electrical conductors embedded in the surface of the track and in this way the car's motor receives power to drive it along. Normally two sets of three parallel strips of conductors are provided to define two lanes around the track. In this way one car can receive power from two of the conductor strips, whether it be positioned in one or other lane, whilst a second car can receive power from the third conductor strip and one of the other two conductor strips in common with the first car, again irrespective of the lane it is following.

There are various ways of causing a car remotely to switch from one lane to the other. The most common uses a change in the polarity of the driving current to the motor to change the direction of rotation of the motor. A drive system is then provided between the motor and the driving wheels which ensures that the drive wheels continue to drive the car in the forward direction irrespective of the direction of the rotation of the motor. A change in the direction of the motor however can be used to control the direction in which the car veers or steers whether to the. left or to the right so as remotely to change from one lane to the other according to the operator's wishes. In this way racing cars can follow a particular lane such as the inside lane at a bend but an operator can arrange for his car to move to the outer lane to overtake a slower car.

It is an object of the invention to provide an improved drive system between the motor and the driving wheels in such cars, the arrangement being simple in construction, reliable in operation and easy to assemble since previous drive systems have not been entirely satisfactory in these respects.

According to the invention there is provided a toy racing car comprising a pair of driven steerable wheels each mounted for king-pin steering and linked by a track rod so that they steer together, each steering wheel being independently rotatable about its own axle rotatably mounted by its respective track arm and having drive gear teeth at the inner end of each axle for driving the axle and its associated steering wheel, an electric drive motor whose direction of rotation depends upon the polarity of the current applied to energise it, a rotatable driven gear pivotally mounted to be movable between limit positions in which it engages and drives the drive gear teeth of one or other axle of the steering wheels, the driven gear engaging with a bevel gear rotated by the drive motor and coaxially rotatable with the axis of pivoting of the driven gear, the engagement between the driven gear and the bevel gear rotating the driven gear and urging and entraining it towards one or other limit position depending upon the direction of rotation of the bevel gear and accordingly the polarity applied to the motor, whereby in one direction of rotation of the motor and bevel gear the driven gear will in one limit position engage the drive gear teeth of one of the steering wheels to rotate that steering wheel in the forward direction and urge the steering wheels to steer in a direction away from the steering wheel being driven, and in the other direction of rotation of the motor and bevel gear the driven wheel will be urged and entrained by the bevel gear to the other limit position in which the other steering wheel is rotated in the forward direction and the steering wheels are urged to steer in the opposite direction away from the steering wheel now being driven.

Such an arrangement is simple and uses a relatively small number of moving parts. It therefore can be reliable in operation and relatively cheap to produce.

Desirably it is the front wheels of the car which are both driven and steered and then the rear wheels can be mounted for idle rotation on the chassis of the car.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a plan view partially section of a toy car according to the invention with its outer body removed; Figure 2 is a section taken on the line 2-2 of Figure 1; Figure 3 is a section taken on the line 3-3 of Figure 1; and Figure 4 is a diagram showing a car racing track on which cars according to the invention are driven.

The toy car 10 shown in the drawings has a chassis 1 2 on which is mounted an electric drive motor 1 4. The car has front steering and driving wheels 16 and 18. It has a pair of non-driven rear wheels 20 which are fixed to a rear axle 22 rotatably journalled in the chassis 1 2.

On the front part of the chassis is mounted an upstanding pin 30 around which is rotatably journalled a bevel gear 32. Also rotatably journalled on the pin 30 is a bush 34 having an integrally formed rod 36 which extends radially out from the bush. In turn, rotatably supported by that rod 36 is a pinion 38.

The motor 14 has an output shaft 40 on which is a drive pinion 44. The bevel gear 32 has inner and outer sets of gear teeth 46 and 48. The drive pinion 44 meshes with the outer set 48 whilst the pinion 38 meshes with the inner set 46. In this way there is a speed reduction. In some cases this may not be necessary in which case there may be only a single set 48 of gear teeth and both pinions 38 and 44 mesh with the teeth of that set.

When the motor 14 is energised, its output shaft rotates the drive pinion 44 and in turn the bevel gear 32. The latter also in turn causes the pinion 38 to rotate. Depending upon the direction of rotation of the bevel gear the freely rotatable bush 34 is entrained in a clockwise or anticlockwise direction in the sense as seen from above as in Figure 1. Thus, when the motor 14 rotates so that the pinion 44 is driven in a clockwise direction as viewed from the front of the car, the bevel gear 32 will rotate in an anticlockwise direction as seen from above entraining with it the pinion 38 away from the position shown in Figure 1. Equally, when the direction of rotation of the motor is reversed to a clockwise direction as seen from above in Figure 1 the pinion will be urged and entrained to and towards the position in which it is shown in Figure 1.

Each steering wheel 1 6 and 18 is mounted on its own sub-axle 50 to which it is firmly fixed. The sub-axle has integrally formed at its inner end an enlarged head 51 provided with an internal bevel gear 52. The pinion 38 can mesh with one or other of these bevel gears 52. The sub-axle 50 is journalled in a track arm 54 having integrally formed with it king-pins 56 which are rotatably journalled between an upper frame 58 and the chassis 12. Each steering wheel can therefore swivel about its king-pin. Each track arm 54 is pivotally linked to a track rod 60 so that both steering wheels steer together in the same direction.

In the position shown in Figure 1 the pinion 38 is to be urged in the clockwise direction as seen from above by the clockwise movement of the bevel gear 32. It therefore engages the bevel teeth 52 in the head 51 of the axle 50 joined to the right-hand steering wheel 1 6 (the right-hand sense being as seen from the rear of the car). It therefore causes the wheel 1 6 to rotate and drive the car forwardly and also causes the steering to pivot in an anti-clockwise direction about the kingpins 56 as seen from above. The car will therefore steer to the left in the sense as seen from the rear of the car, the driving wheel 1 6 being on the outside of the resuiting turn and the fact that that wheel is being driven whilst the wheel 1 8 free wheel tends to assist in the turning to the left.

When the direction of rotation of the motor 14 is reversed, the bevel gear 32 will now rotate in an anti-clockwise direction as seen from above and entrain the pinion 38 so that it now comes to bear against the head 51 linked to the steering wheel 1 8. It will therefore urge the sub-axle 50 associated with that wheel in a clockwise direction and so reverse the direction of steering until the pinion 38 becomes fully engaged with the gear teeth on that head 51 and the pinion 38 no longer reaches a limit position. The car therefore now steers to the right as seen from the rear with the steering wheel 1 8 on the outside of the bend and the fact that this wheel is now driven whilst the steering wheel 1 6 free wheels additionally tend to turn the car to the right.

This arrangement for driving and steering the car 10 is simple and uses a minimum number of moving parts. The parts are easy to assemble and because they are simple the drive system can be relatively cheap. The simplicity of the drive arrangement enhances its reliability.

Resiliently mounted and projecting downwardly from the underneath of the chassis 14 are electrical contacts 80 which are arranged to pick up electrical current from a track for driving the motor 14.

Cars 10 according to the invention can be used on a slotless racing track 200 as shown diagrammatically in Figure 4. As can be seen the track 200 is made up of a number of sections and defined into a left-hand and a right-hand lane. In each lane are embedded three parallel conductor strips and the respective conductor strips of each lane are electrically connected. Two cars 10 according to the invention are shown on the track.

The pickups 26 of the car A could for example contact the central and left-hand conductor strips whilst the car B could be positioned to contact the central and right-hand conductor strip so that each car can be individually energised.

A control box 202 is provided in which the speed of driving of the car is controlled by adjusting a resistance 204 for each car whilst the steering of each car to the left or to the right is controlled by a polarity reverse switch 206.

The track 200 has upstanding flanges 208 at its side edges. A car is steered to bear against these flanges so as to keep the car in its lane.

When the steering direction is changed, the car crosses to the other lane and then bears against the other flange.

Claims (6)

1. A toy racing car comprising a pair of driven steerable wheels each mounted for king-pin steering and linked by a track rod so that they steer together, each steering wheel being independently rotatable about its own axle in tùrn rotatably mounted by its respective track arm and having drive gear teeth at the inner end of each axle for driving the axle and its associated steering wheel, an electric drive motor whose direction of rotation depends upon the polarity of the current applied to energise it, a rotatable driven gear pivotally mounted to be movable between limit positions in which it engages and drives the drive gear teeth of one or other axle of the steering wheels, the driven gear engaging with a bevel gear rotated by the drive motor and coaxially rotatable with the axis of pivoting of the driven gear, the engagement between the driven gear and the bevel gear rotating the driven gear and urging and entraining it towards one or other limit position depending upon the direction of rotation of the bevel gear and accordingly the polarity applied to the motor, whereby in one direction of rotation of the motor and bevel gear the driven gear will in one limit position engage the drive gear teeth of one of the steering wheels to rotate that steering wheel in the forward direction and urge the steering wheels to steer in a direction away from the steering wheel being driven, and in the other direction of rotation of the motor and bevel gear the driven wheel will be urged and entrained by the bevel gear to the other limit position in which the other steering wheel is rotated in the forward direction and the steering wheels are urged to steer in the opposite direction away from the steering wheel now being driven.

2. A toy racing car as claimed in Claim 1 in which the front wheels of the car are both driven and steered and the rear wheels are mounted for idle rotation on a chassis for the car.

3. A toy racing car as claimed in either preceding claim in which for supporting each driven steerable wheel a spindle rotatably mounted in the track arm is provided, that spindle having an integrally formed enlarged head on one side of the track arm and being fixed to the steering wheel on the other side, the enlarged head being provided with internal bevel gear teeth which can be engaged by a driven gear to drive that wheel.

4. A toy racing car as claimed in any preceding claim in which upstanding from a chassis for the vehicle is a pivot pin about which the bevel gear is freely rotatable, the bevel gear having two coaxial sets of integrally formed teeth one set being engaged and driven by an output pinion from the drive motor and the other set engaging and driving the rotatable driven gear, the rotatable driven gear being rotatably mounted on a rod extending radially out from a bush freely mounted on the pivot pin.

5. A toy racing car substantially as herein described with reference to the accompanying drawings.

6. A toy racing car system comprising a track having electrical conductors embedded in its surface to provide two sets of three parallel strips of conductors defining two lanes and the track having upstanding edges, and two cars as claimed in any preceding claim provided with electrical pickups to receive power from a respective pair of the conductor strips in either lane, means for applying a variable electrical power across the respective pair of strips to vary the speed of each car, and means to alter the polarity of the electrical power to cause a car to steer in an opposite direction so as to switch from one lane to another.