GB2186049A

GB2186049A - A spring motor

Info

Publication number: GB2186049A
Application number: GB08602661A
Authority: GB
Inventors: Louis Kam Kong Ma
Original assignee: YAT MING IND FACTORY Ltd
Current assignee: YAT MING IND FACTORY Ltd
Priority date: 1986-02-04
Filing date: 1986-02-04
Publication date: 1987-08-05
Also published as: GB8602661D0

Abstract

The rear wheels of a toy motor car are fixed to a horizontal shaft (11) connected to the driven gear (6) of a spring motor. The motor incorporates a spiral spring mounted in and connected to the housing (1), and coupled to a driving gear (2). A stepped pinion (7 and 8) is mounted in engagement with the driving gear (2) and vertically above the driven gear (6) on a shaft (9) which extends through vertical slots (10) within the housing (1). A winding cord (5) is wound around a drum (4) attached to the driving gear (2) so that when the end (17) is withdrawn from the vehicle, the gear (2) is rotated in reverse direction to wind the spring (3), and this reverse rotation lifts the stepped pinion out of engagement with driven gear (6) so that the driving wheel of the vehicle are not rotated. On release of cord (5), the spring (3) rotates the driving gear (2) in the driving direction. The resultant force transmitted from the driving gear (2) to the stepped pinions reinforces the weight of the stepped pinion in urging the stepped pinion to mesh the driven gear (6) and thus rotate the driving wheels of the car. <IMAGE>

Description

SPECIFICATION A spring motor Field of the Invention The invention relates to a spring motor for use in toy vehicles and in particular, in toy vehicles which only travel in one direction.

Background Art One known form of spring motor comprises a housing; a driving gear mounted within the housing for rotation in driving and reverse directions; spring means mounted within the housing and connected to the housing and to the driving gear; winding means for rotating the driving gear in the reverse direction so as to load the spring means and thereby store energy in the spring means; a driven gear rotatably mounted within the housing; idler gear means engageable with the driving and driven gears; and mounting means which maintain the idler gear means in driving engagement with the driving and driven gears when the driving gear is rotated in the driving direction, but permit the idler gear means to break driving engagement with at least one of the driving and driven gears when the driving gear is rotated in the reverse direction.

UK Patent Specification No. 2032 786 discloses a spring motor such as this in which the driven gear forms part of the winding means and is mounted for rotation about a transversely movable axis so as to move into and out of engagement with at least one other gear so that when the driven gear is moved from a first position to a second position, the driven gear can be rotated in first and second directions and, in both cases, the driving gear is rotated in the reverse direction so as to store energy in the spring motor.

Although this spring motor provides a very ingenious mechanism for driving a toy vehicle, this construction is quite complicated and is therefore costly.

Disclosure of the Invention It is the purpose of the present invention to reduce these disadvantages and to provide a spring motor of simpler and less expensive construction.

This is achieved by ensuring that the driven gear is mounted for rotation about a fixed axis and the winding means are independent of the driven gear.

Thus, according to the invention, there is provided a spring motor comprising a housing; a driving gear mounted within the housing for rotation in driving and reverse directions; a driven gear mounted within the housing for rotation about a fixed axis; idler means engageable with the driving and driven means; mounting means which maintain the idler gear means in driving engagement with the driving and driven gears when the driving gear is rotated in the driving direction, but permit the idler gear means to beak driving engagement with at least one of the driving and driven gears when the driving gear is rotated in the reverse direction; spring means mounted within the housing and connected to the housing and to the driving gear; and winding means which are independent of the driven gear, for rotating the driving gear in the reverse direction so as to load the spring means and thereby store energy in the spring means.

By this means, the construction is simplified in that there is no need to mount the driven gears so that it can be deflected into and out of engagement with cooperating gears and simplified winding means may be employed.

In a preferred embodiment of the invention, the driving and driven gears are mounted for rotation about parallel horizontal axes. In this case, the weight of the idler gear means can contribute to the positioning of the idler gear means relative to the driving and driven gears.

It is also preferred to provide idler gear means which comprise at least one gear which has a horizontal rotation axis of the driving gear and is disposed on one side of the driving gear and above or below the driven gear. In this case, the weight of the idler gear means acts directly to urge the idler gear means into or out of engagement with the driven gear.

With this form of construction, the idler gear means preferably comprise a compound reduction gear. This enables the driving and driven gears to be spaced sufficiently apart to ensure that they do not engage each other directly in that the part of the compound gear engaging the driving gear has a smaller radius than the part of the compound gear engaging the driven gear. However, the idler gear means can comprise a single gear or a gear train.

In one practical embodiment of the invention, the winding means comprise a drum, which is rotatable with the driving gear, and a winding cord wound around the drum. When such a spring motor is fitted to a toy vehicle having a driven shaft which is rotatable by the driven gear and at least one driven wheel rotatable with the driving shaft, it is possible to hold the vehicle stationary on a rolling surface, to withdraw the end of the winding cord, and then to release the winding cord and the toy vehicle to allow the vehicle to travel along the rolling surface, driven by the spring motor.

A spring motor, embodying the present inventon is hereinafter described, by way of example only, with reference to the accompanying drawings.

Brief Description of the Drawings Figure 1 is schematic side elevation of a spring motor; Figure 2 is a plan view of the spring motor shown in Fig. 1, Figure 3 is a schematic side elevation of a toy vehicle incorporating a motor as shown in Figs; 1 and 2.

Mode for Carrying Out the Invention As shown in Figs. 1 and 2 a main shaft 14 is mounted for rotation in a housing 1. A driving gear 2 is mounted for rotation with the main shaft 14 and a spiral spring 3 mounted within the housing 1 is connected, at opposite ends, to the housing 1 and to the main shaft 14. A drum 4 formed integral with the driving gear 2 and a winding cord attached to the drum 4 and wound around the drum 4 together constitute winding means for winding the spring motor. A compound reduction gear 7 and 8 has a shaft 9 which is movable in vertical slots 10 formed in opposite sides of the housing 1 and has a first part 7 engaging the driving gear 2 and a larger diameter second part 8 engaging a driven gear 6. Driven gear 6 meshes with an output gear 15 mounted on a driven shaft 11.

As shown in Fig. 1, compound gears 7 and 8 is disposed substantially vertically above driven gear 6 so that when the end of the winding cord 5 is withdrawn from the winding motor, the driving gear 2 and main shaft 14 are rotated in a reverse, anti-clockwise direction so as to load the spiral spring 3 to thereby store energy. This motion of the driving gear 2, in the reverse direction, causes the compound gear 7 and 8 to be lifted out of engagement with the driven gear 6 and the shaft 9 of the compound gear 7 and 8 moves upwardly along the slots 10. As a result, the driven gear 6 and the driven shaft 11 are not rotated.

When the winding cord 5 is then released, the spiral spring 3 causes the main shaft 14 and the driving gear 2 to rotate in the forward, clockwise direction. This forward motion of the driving gear urges the compound gear 7 and 8 downwards into engagement with the driven gear 6 so as to cause the driven gear 6 and the driven shaft 11 to rotate.

In the toy car 12 shown in Fig. 3, incorpoating a spring motor in accordance with that shown in Figs. 1 and 2, driven wheels 13 are mounted at opposite ends of the driven shaft 11 and constitute the rear wheels of the toy car 12. When the toy car 12 is held on a rolling surface 16 and the winding cord 5 is withdrawn from the spring motor, the spiral spring 3 is wound up without rotation of the driven gear 6, output gear 15, driven shaft 11 or driven wheels 13. When the winding cord 5 and the car 12 are then released, the spiral spring 3 drives the driving gear 2 clockwise, in the driving direction, this results in anticlockwise rotation of the output gear 15, driven shaft 11 and driven wheels 13, thus causing the toy car 12 to travel in a forward direction.

Claims

1. A spring motor comprising: a housing (1); a driving gear (2) mounted within the hous ing (1) for rotation in driving and reverse di rections; spring means (3) mounted within the hous ing (1) and connected to the housing (1) and to the driving gear (2); winding means (4 and 5) for rotating the driving gear (2) in the reverse direction so as to load the spring means (3) and thereby store energy in the spring means (3); a driven gear (6) rotatably mounted within the housing (1); idler gear means (7 and 8) engageable with the driving and driven gears (2 and 6); and mounting means (9 and 10) which maintain the idler gear means (7 and 8) in driving en gagement with the driving and driven gears (2 and 6) when the driving gear (2) is rotated in the driving direction, but permit the idler gear means (7 and 8) to break driving engagement with at least one of the driving and driven gears (2 and 6) when the driving gear (2) is rotated in the reverse direction; characterised in that: the driven gear (6) is mounted for rotation about a fixed axis (10); and the winding means (4 and 5) are independent of the driven gear (6).

2. A motor, according to Claim 1, in which the driving and driven gears (2 and 6) are mounted for rotation about parallel horizontal axes.

3. A motor, according to Claim 2, in which the idler gear means (7 and 8) comprise at least one gear (7 or 8) which has a horizontal rotational axis parallel to the rotational axis of the driving gear (2) and is disposed on one side of the driving gear (2) and above or be low the driven gear (6).

4. A motor, according to any preceding claim, in which the idler gear means (7 and 8) comprise a compound reduction gear.

5. A motor, according to any preceding claim, in which the winding means (4 and 5) comprise a drum (4), which is rotatable with the driving gear (2), and a winding cord (5) wound around the drum (4).

6. A toy vehicle (12), fitted with a spring motor according to any preceding claim, in which a driven shaft (11) is driven by the driven gear (6) and at least one driven wheel (13) is rotatable with the driven shaft (11).

7. A spring motor, substantially as herein before described with reference to and illus trated in Figs. 1 and 2 of the accompanying drawings.

8. A toy vehicle (12) substantially as here inbefore described with reference to and illus trated in Fig. 3 of the accompanying draw ings.