GB1568700A

GB1568700A - Wind-up spring drive mechanism

Info

Publication number: GB1568700A
Application number: GB4685276A
Authority: GB
Original assignee: Shinsei Industries Co Ltd; Shinsei Kogyo KK
Current assignee: Shinsei Industries Co Ltd; Shinsei Kogyo KK
Priority date: 1976-05-11
Filing date: 1976-11-10
Publication date: 1980-06-04
Also published as: HK10281A; JPS52151894U

Description

(54) WIND-UP SPRING DRIVE MECHANISM (71) We, SHINSEI KOGYO COMPANY LIMITED, a Japanese Company, of 27-23, 2-chome, Sumida, Sumida-ku, Tokyo, Japan 131, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a wind-up spring drive mechanism particularly, although not exclusively, for a toy wheeled vehicle of the type having power stored in a spring which is wound up by drawing the toy backwards with the vehicle wheels pressed against the floor or ground, the vehicle being propelled forward by the drive wheels driven by the power stored in the spring, when the hand is released.

According to the present invention there is provided a wind-up spring drive mechanism comprising a driven spindle rotatably mounted in a frame, first and second gear wheels mounted coaxially on a winding spindle in the frame for rotation re1ative to the frame and to each other, a coil spring located around the winding spindle between the first and second gear wheels and having one end connected for rotation with the first gear wheel and the other end connected for rotation with the second gear wheel so that relative rotation of the first and second gear wheels in one direction winds up the spring, the second gear wheel being provided with non-reverse means acting between it and the frame to permit rotation of the second gear wheel relative to the frame only in one direction corresponding to winding up of the spring, the first and second gear wheels being drivingly connected with the driven spindle by respective first and second gear trains one of which consists of an even number of gears and the other of which consists of an odd number of gears, the second gear train including an intermediate gear which is mounted disengageably in such a way that rotation of the driven spindle by external means in one direction causes the said disengageable gear of the second gear train to become engaged and the first and second gear wheels are rotated simultaneously in mutually opposite directions to wind up the spring, and the said disengageable gear is moved automatically to its disengaged position by rotation of the driven spindle, under the drive of the spring, in the other rotary direction via the first gear train and remains in the disengaged position when the driven spindle is rotated by external means in the said other direction. In practice, where the drive mechanism is employed as the drive unit for a toy wheeled vehicle, the external means for rotating the driven spindle in the said one direction to cause the spring to be wound up is constituted by a person drawing the vehicle backwards with the vehicle wheels contacting the floor.

Preferably, the first gear train comprises four gears consisting of the said first gear wheel, a pinion on the driven spindle and two intermediate gears, and the second gear train comprises three gears consisting of the said second gear wheel, a pinion on the driven spindle and the said disengageable intermediate gear. This provides a particularly simple arrangement which is inexpensive to manufacture.

Advantageously, an intermediate gear of the first gear train is disengageably mounted in such a way that it is automatically engaged when the driven spindle is rotated in the said one direction to wind the spring and when the driven spindle is driven by the spring in the other rotary direction, and is automatically disengaged when the spring is unwound and the driven spindle is rotated by external means in its said other rotary direction.By virtue of this feature, when the drive mechanism is employed as the drive unit of a toy wheel vehicle, the vehicle is permitted to continue to run forward under its own momen tum after the spring is completely unwound, with the drive wheels of the vehicle and the driven spindle free wheeling out of driving conection with either the said first or second gear wheels Preferably, a spring drum is provided in which the spring is located, and conveniently the drum is connected to the second gear wheel for rotation therewith; for example the first gear may be mounted for rotation with the winding spindle and the spring drum, conveniently formed integrally with the second gear wheel, may be mounted rotatably relative to the winding spindle, the inner end of the spring being secured to the winding spindle and the outer end of the spring being connected to the circumferential portion of the drum.

To prevent the spring being over-wound, i.e. wound so tight that it may be broken, its outer end is preferably provided with an abutment and the inside of the drum circumference provided with a plurality of spaced abutments, whereby the spring abutment engages one of the abutments on the drum in a manner permitting the spring abutment to jump from abutment to abutment of the drum when the first and second gear wheels are rotated further in the winding direction once the spring is fully wound.

The invention may be carried into practice in a number of ways but one specific embodiment will now be described by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a plan view of a wind-up spring drive mechanism, in accordance with the invention, constituting the drive unit for a toy wheeled vehicle, Figure 2 is a section taken on the line II-II of Figure 1, Figure 3 is a section taken on the line Ill-Ill of Figure 1, Figure 4 is a cross-section of the spring and the spring drum of the mechanism of Figure 1, and Figure 5 is a perspective view of part of the mechanism of Figure 1.

The drive unit, for a toy wheeled vehicle, as illustrated consists of: a winding spindle 2 and a wheel spindle 3 rotatably supported by a chassis 1; a take-up gear wheel 4, comprising a first gear wheel, fixed to the winding spindle 2 and a dual width pinion 5 fixed to the wheel spindle 3; a spring drum 6, provided with a plurality of engaging grooves 14 inside its circumferential wall and made of hard synthetic resin, carried by the winding spindle 2 for rotation relative to the spindle 2; and furthermore, a spring 7 located inside the spring drum 6 with its inner end 15 secured to the winding spindle 2 and with an engagement abutment 16 formed by a bend, at the outer end 15' of the spring 7, engaging with one of the engaging grooves 14 in a manner permitting the engagement abutment to jump from groove 14 to groove 14 to prevent the spring 7 being over-wound if an attempt is made to wind up the spring further once it is fully wound. In addition, a ratchet gear wheel 8, comprising a second gear wheel, is formed integrally with one side of the spring drum 6, and a pawl 9, consisting of spring-loaded tongue 25 having a toothed part 26 and formed of synthetic plastics material having slight elasticity, is pivoted on the chassis 1 for cooperation with the ratchet wheel 8.A pin 27 limits the pivotal movement of the pawl 9 in one direction and a further pin 28 presses against the spring-loaded tongue 25, both pins being affixed to the chassis 1.

Between the pinion 5 and the take-up gear wheel 4 there is provided an intermediate gear 10, to ensure that the first gear wheel 4 and the wheel spindle 3 rotate in opposite rotary directions when they are drivingly connected, and a clutch gear 11 adapted to be engaged while the spring 7 is being wound up and unwinding and to be disengaged when the spring 7 is completely unwound as will be further explained below; the take-up gear wheel 4, the intermediate and clutch gears 10 and 11, and the pinion 5 constitute a first gear train. An arm 20 is pivotally mounted cn the wheel spindle 3, the arm having a pin shaft 19 located at the end of the arm 20, disposed parallel to the wheel spindle 3 and with one end fitting freely into an arcuate slot 21, having the wheel spindle 3 as the centre, in a side wall of the chassis 1.A further clutch gear 12, borne rotatably by the pin shaft 19 engages the pinion 5 in all positions of the arm 20. The arm 20 is adapted to pivot between a position in which the clutch gear 12 meshes with the ratchet wheel 8 and a position in which the clutch gear 12 is disengaged from the ratchet wheel 8. This arrangement is such that the clutch gear 12 will engage with the ratchet wheel 8 when the spring 7 is being wound up, and will disengage from the ratchet wheel 8 when the spring 7 is unwinding to drive the wheel spindle 3 via the first gear train; it will also remain disengaged when the spring 7 is unwound and the wheel spindle 3 continues to rotate in the forward drive direction. The freely pivoting mounting of the arm 20 is assisted by the provision of a counterweight 20A (see Figure 5) at the opposite end of the arm 20 from the end at which the clutch gear 12 is carried: as will be appreciated from Figure 3, - owing to the free pivoting action of the arm 20, when the pinion 5 is rotated clockwise the clutch gear 12 will be lifted into engagement with the ratchet wheel 8, so that the ratchet wheel 8, the clutch gear 12 and the pinion 5 form a second gear train, and when the pinion 5 is rotated anticlockwise the clutch gear 12 will be urged down out of engagement with the ratchet wheel 8.

The engagement and disengagement of the clutch gear 11 in the first gear train is afforded by the provision of a slot 18 for supporting the spindle 11' on which the clutch gear 11 is carried. As will be appreciated from Figure 3, the slot 18 is such that the clutch gear 11 always remains in mesh with the take-up gear wheel 4 but will be disengaged from the intermediate gear 10 when the clutch gear 11 is in its upper position.If the pinion 5 is rotated by external means in a clockwise direction, the consequent anticlockwise rotation of the intermediate gear 10 will cause a downward force to be exerted on the clutch gear 11 and will thus cause the clutch gear 11 to be retained in or move to its lower position and if the take-up gear 4 is driven in rotation by the unwinding spring 7 in a clockwise direction again a downward force will be exerted on the clutch year 11 so that the latter will also be retained in or moved to its lower positoin during driving; however if the pinion 5 is rotated by external means in an anticlockwise direction, as would occur during free-wheeling, the consequent clockwise rotation of the intermediate gear 10 will exert an upward force on the clutch gear 11 and this upward force will cause the clutch gear 11 to be lifted by movement of its spindle 11' in the slot 18, out of drive engagement with the intermediate gear 10 so breaking the drive connection in the first gear train to allow freewheeling; in this condition the teeth of the intermediate gear 10 simply slide under the teeth of the clutch gear 11 keeping the latter gear lifted.

For use as the drive unit of a toy wheeled vehicle, the wheel spindle 3 is provided with drive wheels 23 which will constitute the rear wheels of the vehicle, and a pair of freely rotatable front wheels 22 are also provided.

The modes of operation are as follows: when at first, the rear and front wheels 22 and 23 are pressed against, for example, the floor and the whole toy is pulled backwards, the rear wheels 23, the wheel spindle 3, and the pinion 5 will turn in the direction of the arrows of Figures 2 and 3, the clutch gears 11 and 12 will become engaged, and the torque of the pinion 5 will be transmitted through the intermediate gear 10, the clutch gear 11, the take-up gear wheel 4, and the winding spindle 2, to the inner end of the spring 7, and also through the clutch gear 12, the ratchet wheel 8, and the spring drum 6, to the outer end of the spring 7, thus storing power by winding up the spring 7 in two opposite directions from the respective inner end and outer end at the same time.The op- posite directions of rotation of the take-up gear 4 and the drum and ratchet wheel 8 are achieved by virtue of there being an odd number of gears (three) in the second gear train and an even number of gears (four) in the first gear train. When the spring 7 is fully wound the engagement abutment 16 will jump from groove 14 to groove 14 on the inside of the spring drum 6 thus preventing breakage of the spring 7 or the damaging of other parts which might result from overwinding the spring 7.Subsequently the whole toy is left on the floor, and the releasing force of the spring 7 will be transmitted through the winding spindle 2, the take-up gear wheel 4, the clutch gear 11 and the intermediate gear 10 to the pinion 5 thereby to drive the wheel spindle 3 in a direction so that the drive wheels 23 propel the vehicle forwards; the starting of rotation of the pinion 5 causes the clutch gear 12 automatically to become disengaged from the ratchet wheel 8. The ratchet wheel 8 will be prevented from rotating in its reverse direction, i.e. to unwind the spring 7, by the pawl 9 engaging the ratchet wheel and abutting the stop 27.

After the spring 7 is completely unwound the clutch gear 11 will become disengaged because the take-up gear 4 will no longer be exerting a downward force on the clutch gear 11 and the intermediate gear 10 will be rotated clockwise by the wheels to exert an upward force on the clutch gear 11, thereby lifting it to break the connection between the take-up gear 4 and the wheel spindle 3 and allowing the rear wheels 23, the wheel spindle 3, the pinion 5, and the intermediate gear 10 to be rotated freely as the momentum of the vehicle carries it forwards and thus allow the continued running of the toy until all the momentum is lost.

Since the running top is capable of storing power by winding up the spring from the two opposite directions of rotation of the inner and outer ends of the spring, the invention has the advantage, when storing power, to accomplish winding up of the spring with about half the amount of winding rotations of the wheel spindle compared with a toy of this type winding up the spring at one end only; furthermore, the clutch gears of the first and second gear trains become enraged or disengaged entirely automatically under the action of the rotation of the various gears and spindles.

WHAT WE CLAIM IS: - 1. A wind-up spring drive mechanism

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. wheel 8, so that the ratchet wheel 8, the clutch gear 12 and the pinion 5 form a second gear train, and when the pinion 5 is rotated anticlockwise the clutch gear 12 will be urged down out of engagement with the ratchet wheel 8. The engagement and disengagement of the clutch gear 11 in the first gear train is afforded by the provision of a slot 18 for supporting the spindle 11' on which the clutch gear 11 is carried. As will be appreciated from Figure 3, the slot 18 is such that the clutch gear 11 always remains in mesh with the take-up gear wheel 4 but will be disengaged from the intermediate gear 10 when the clutch gear 11 is in its upper position.If the pinion 5 is rotated by external means in a clockwise direction, the consequent anticlockwise rotation of the intermediate gear 10 will cause a downward force to be exerted on the clutch gear 11 and will thus cause the clutch gear 11 to be retained in or move to its lower position and if the take-up gear 4 is driven in rotation by the unwinding spring 7 in a clockwise direction again a downward force will be exerted on the clutch year 11 so that the latter will also be retained in or moved to its lower positoin during driving; however if the pinion 5 is rotated by external means in an anticlockwise direction, as would occur during free-wheeling, the consequent clockwise rotation of the intermediate gear 10 will exert an upward force on the clutch gear 11 and this upward force will cause the clutch gear 11 to be lifted by movement of its spindle 11' in the slot 18, out of drive engagement with the intermediate gear 10 so breaking the drive connection in the first gear train to allow freewheeling; in this condition the teeth of the intermediate gear 10 simply slide under the teeth of the clutch gear 11 keeping the latter gear lifted. For use as the drive unit of a toy wheeled vehicle, the wheel spindle 3 is provided with drive wheels 23 which will constitute the rear wheels of the vehicle, and a pair of freely rotatable front wheels 22 are also provided. The modes of operation are as follows: when at first, the rear and front wheels 22 and 23 are pressed against, for example, the floor and the whole toy is pulled backwards, the rear wheels 23, the wheel spindle 3, and the pinion 5 will turn in the direction of the arrows of Figures 2 and 3, the clutch gears 11 and 12 will become engaged, and the torque of the pinion 5 will be transmitted through the intermediate gear 10, the clutch gear 11, the take-up gear wheel 4, and the winding spindle 2, to the inner end of the spring 7, and also through the clutch gear 12, the ratchet wheel 8, and the spring drum 6, to the outer end of the spring 7, thus storing power by winding up the spring 7 in two opposite directions from the respective inner end and outer end at the same time.The op- posite directions of rotation of the take-up gear 4 and the drum and ratchet wheel 8 are achieved by virtue of there being an odd number of gears (three) in the second gear train and an even number of gears (four) in the first gear train. When the spring 7 is fully wound the engagement abutment 16 will jump from groove 14 to groove 14 on the inside of the spring drum 6 thus preventing breakage of the spring 7 or the damaging of other parts which might result from overwinding the spring 7.Subsequently the whole toy is left on the floor, and the releasing force of the spring 7 will be transmitted through the winding spindle 2, the take-up gear wheel 4, the clutch gear 11 and the intermediate gear 10 to the pinion 5 thereby to drive the wheel spindle 3 in a direction so that the drive wheels 23 propel the vehicle forwards; the starting of rotation of the pinion 5 causes the clutch gear 12 automatically to become disengaged from the ratchet wheel 8. The ratchet wheel 8 will be prevented from rotating in its reverse direction, i.e. to unwind the spring 7, by the pawl 9 engaging the ratchet wheel and abutting the stop 27. After the spring 7 is completely unwound the clutch gear 11 will become disengaged because the take-up gear 4 will no longer be exerting a downward force on the clutch gear 11 and the intermediate gear 10 will be rotated clockwise by the wheels to exert an upward force on the clutch gear 11, thereby lifting it to break the connection between the take-up gear 4 and the wheel spindle 3 and allowing the rear wheels 23, the wheel spindle 3, the pinion 5, and the intermediate gear 10 to be rotated freely as the momentum of the vehicle carries it forwards and thus allow the continued running of the toy until all the momentum is lost. Since the running top is capable of storing power by winding up the spring from the two opposite directions of rotation of the inner and outer ends of the spring, the invention has the advantage, when storing power, to accomplish winding up of the spring with about half the amount of winding rotations of the wheel spindle compared with a toy of this type winding up the spring at one end only; furthermore, the clutch gears of the first and second gear trains become enraged or disengaged entirely automatically under the action of the rotation of the various gears and spindles. WHAT WE CLAIM IS: -

1. A wind-up spring drive mechanism

comprising a driven spindle rotatably mounted in a frame, first and second gear wheels mounted coaxially on a winding spindle in the frame for rotation relative to the frame and to each other, a coil spring located around the winding spindle between the first and second gear wheels and having one end connected for rotation with the first gear wheel and the other end connected for rotation with the second gear wheel so that relative rotation of the first and second gear wheels in one direction winds up the spring, the second gear wheel being provided with non-reverse means acting between it and the frame to permit rotation of the second gear wheel relative to the frame only in one direction corresponding to winding up of the spring, the first and second gear wheels being driving'y connected with the driven spindle by respective first and second gear trains one of which consists of an even number of gears and the other of which consists of an odd number of gears, the second gear train including an intermediate gear which is mounted disengageably in such a way that rotation of the driven spindle by external means in one direction causes the said disengageable gear of the second gear train to become engaged and the first and second gear wheels are rotated simultaneously in mutually opposite directions to wind up the spring, and the said disengageable gear is moved automatically to its disengaged position by rotation of the drive spindle, under the drive of the spring, in the other rotary direction via the first gear train and remains in the disengaged position when the driven spindle is rotated by external means in the said other direction.

2. A drive mechanism as claimed in claim 1, in which the first gear train comprises four gears consisting of the said first gear wheel, a pinion on the driven spindle and two intermediate gears, and the second train - comprises three gears consisting of the said second gear wheel, a pinion on the driven spindle and the said disengageable intermediate gear.

3. A drive mechanism as claimed in claim 2, in which the disengageable intermediate gear of the second gear train is mounted on a pin shaft disposed parallel to the driven spindle and carried at one end of an arm which is pivotally mounted on the drive spindle so that the intermediate gear is in constant mesh with the pinion on the driven spindle, the arm being pivotable between a position in which the intermediate gear meshes with the said scond gear wheel and a position in which the intermediate gear is out of mesh with the said second gear wheel.

4. A drive mechanism as claimed in claim 3, in which a pin on the arm is located in an arcuate slot of the frame, the arcuate slot defining the pivoting movement of the arm.

5. A drive mechanism in as claimed in claim 3 or claim 4, in which in the intended use position of the drive mechanism the arm is generally horizontal, and in which a counterweight is provided at the other end of the arm from the intermediate gear at the other side of the pivotal axis of the arm.

6. A drive mechanism as claimed in any one of claims 1 to 5, in which an intermediate gear of the first gear train is disengageably mounted in such a way that it is automatically engaged when the driven spindle is rotated in the said one direction to wind the spring and when the driven spindle is driven by the spring in the other rotary direction, and is automatically disengaged when the spring is unwound and the driven spindle is rotated by external means in its said other lotary direction.

7. A drive mechanism as claimed in any one of claims 2 to 5 and claims 6, in which the disengageably mounted intermediate gear of the first gear train is that meshing with the first gear wheel.

8. A drive mechanism as claimed in claim 7, in which the said disengageably mounted intermediate gear of the first gear train is adapted to move into and out of meshing engagement with the other intermediate gear of the first gear train.

9. A drive mechanism as claimed in any one of the preceding claims in which there is provided a spring drum in which the spring is located.

10. A drive mechanism as claimed in claim 9, in which the spring drum is connected to the second gear wheel for rotation therewith.

11. A drive mechanism as claimed in claim 10, in which. the first gear is mounted for rotation with the winding spindle, and in which the spring drum and second gear wheel are mounted rotatably, relative to the winding spindle, the inner end of the spring being secured to the winding spindle and the outer end of the spring being connected to the circumferential portion of the spring drum.

12. A drive mechanism as claimed in claim 11, in which the outer end of the spring is provided with an abutment, and the inside of the circumference of the spring drum is provided with a plurality of abutments spaced therearound, whereby the spring abutment engages one of the abutments in the drum in a manner permitting the spring abutment to jump from abutment to abutment of the spring drum when the first and second gear whee's are rotated further in the winding direction once the spring is fully wound, thereby to prevent the spring being overwound.

13. A drive mechanism as claimed in claim 12, in which the abutments provided in the spring drum are afforded by grooves or recesses in the circumferential wall of the drun

14. A drive mechanism as claimed in any one of claims 9 to 13, in which the spring drum and the second gear wheel are integral.

15. A drive mechanism as claimed in any one of the preceding claims, in which the non-reverse means acting between the second gear wheel and the frame comprises a pawl carried by the frame for cooperating with the second gear wheel as a ratchet wheel.

16. A drive mechanism as claimed in any one of the preceding claims, adapted to serve as the drive unit of a toy wheeled vehicle, the driven spindle being provided with wheels.

17. A toy wheeled vehicle having a drive unit comprising a drive mechanism as claimed in claim 16, the mechanism being adapted so that when the vehicle is drawn backwards over a surface the wheels are rotated and the driven spindle rotates in the said one direction, thereby to wind the spring, and when the toy is released with the spring wound, the latter causes the vehicle to be propelled forward.

18. A wind-up spring drive mechanism substantially as specifically described herein with reference to the accompanying drawings.

19. A toy wheeled vehicle having a drive mechanism as claimed in claim 17.