GB2156695A

GB2156695A - Yo-yo type toy

Info

Publication number: GB2156695A
Application number: GB08408463A
Authority: GB
Inventors: Seung Ki Kim
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-04-02
Filing date: 1984-04-02
Publication date: 1985-10-16
Also published as: GB8408463D0

Abstract

A toy comprises a flywheel (4) having a waisted portion to which a string (7) is attached and around which the string (7) can be wound. The toy operates as a yo-yo, except that a proportion of the rotational energy of the flywheel (4) is converted into rotation of a propeller (6) by means of a gear wheel (3) and a crown gear (5). The propeller (6) is rotatably mounted on a toy helicopter body (1) and the flywheel (4) rotates in bearings formed inside the helicopter body (1). <IMAGE>

Description

SPECIFICATION A toy THIS INVENTION relates to a toy.

A previously proposed toy is known as a yoyo and comprises a comparatively heavy, for example wooden, disc having a circumferential groove defining a waisted portion to which a string (which may be elastic) is attached and around which the string can be wound. The free end of the string can be provided with a ring or knob. In use, the string is wound around the waisted portion, the ring or knob is grasped in the user's hand and the yo-yo is allowed to fall, unwinding the string. When the string is completely unwound the heavy disc, which acts as a flywheel, continues to rotate because of its own inertia, thus winding up the string in the opposite direction. The yoyo can be made to rise and fall indefinitely, the necessary additional energy being supplied for example by tugging on the string as the disc reaches its lowest point.

The present invention provides a toy comprising a flywheel and means for converting gravitational potential energy of the flywheel into rotational kinetic energy of the flywheel and vice versa, which toy further comprises a member which is movable with respect to or about the axis of rotation of the flywheel and means for transmitting a proportion of kinetic energy of the flywheel to the movable member.

Thus, the present invention enables the provision of a novel and interesting toy.

For a better understanding of the present invention, and to show how the sAme may be put into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is an exploded perspective view of a toy helicopter in accordance with the invention, Figure 2 is a vertical cross-sectional view of the toy helicopter of Fig. 1, and Figure 3 is a side elevational view of a toy aeroplane in accordance with the invention.

Referring now to Fig. 1, the toy helicopter comprises a body having a left half 1 and a right half 1', the two halves being connected to one another by means of two screws passing therethrough. A flywheel is rotatably mounted in the body by means of shafts 2 which are fixed to or integrally formed with the flywheel and seat in bearings formed on the inner surface of the helicopter body. The flywheel is integrally and coaxially formed with a gear wheel 3 and comprises a left half 4 and a right half 4' which are connected by a waisted portion 9 to which a string 7 is attached and around which the string 7 can be wound. The free end of the string 7 is provided with a knob 8.

A crown gear 5 and a propeller 6 are integrally formed with and connected by a bored cylindrical shaft which extends rotatably through an aperture formed in the top of the helicopter body so that the crown gear 5 is disposed inside, and the propeller 6 outside, the helicopter body. The crown gear 5 meshes with the gear wheel 3 and the string 7 extends through the bore of the cylindrical shaft so that the knob 8 is outside the helicopter body. The cylindrical shaft is held against axial movement by an outer collar which is integrally formed with the helicopter body and abuts the boss of the propeller 6 and an inner collar (not shown in Fig. 1) which is also integrally formed with the helicopter body and abuts the upper surface of the crown gear 5.

In use, the string 7 is wound onto the waisted portion 9, for example by rotating the propeller 6, the knob 8 is grasped in the user's hand and the helicopter body is allowed to fall, causing rotation of the flywheel as the string 7 is unwound. When the string 7 is completely unwound the flywheel continues to rotated because of its own inertia and this causes the string 7 to be wound onto the waisted portion 9 again in the opposite direction. The toy helicopter thus repeatedly rises and falls. This motion can be caused to continue indefinitely by a skilled user, for example by tugging on the string 7 when the helicopter body is at its lowest point. In this respect the toy is similar to a conventional yoyo. However, unlike a conventional yo-yo, the flywheel also transmits rotation to the propeller 6.

Turning now to Fig. 3, the toy aeroplane is constructed and operates in a manner substantially similar to that of the toy helicopter, except that the cylindrical shaft bearing the propeller 6 and the crown gear 5 extends rotatably through an aperture formed in the nose of the aeroplane body.

The toy helicopter and the toy aeroplane can be manufactured from a rigid lightweight plastics material, the flywheel preferably comprising a dense material such as wood.

1. A toy comprising a flywheel and means for converting gravitational potential energy of the flywheel into rotational kinetic energy of the flywheel and vice versa, which toy further comprises a member which is movable with respect to or about the axis of rotation of the flywheel and means for transmitting a proportion of kinetic energy of the flywheel to the movable member.

2. A toy according to Claim 1, which toy comprises a body, wherein the flywheel is rotatably mounted with respect to the body and the movable member is movably mounted with respect to the body.

3. A toy according to Claim 2, wherein the body is hollow and the flywheel is rotata

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A toy THIS INVENTION relates to a toy. A previously proposed toy is known as a yoyo and comprises a comparatively heavy, for example wooden, disc having a circumferential groove defining a waisted portion to which a string (which may be elastic) is attached and around which the string can be wound. The free end of the string can be provided with a ring or knob. In use, the string is wound around the waisted portion, the ring or knob is grasped in the user's hand and the yo-yo is allowed to fall, unwinding the string. When the string is completely unwound the heavy disc, which acts as a flywheel, continues to rotate because of its own inertia, thus winding up the string in the opposite direction. The yoyo can be made to rise and fall indefinitely, the necessary additional energy being supplied for example by tugging on the string as the disc reaches its lowest point. The present invention provides a toy comprising a flywheel and means for converting gravitational potential energy of the flywheel into rotational kinetic energy of the flywheel and vice versa, which toy further comprises a member which is movable with respect to or about the axis of rotation of the flywheel and means for transmitting a proportion of kinetic energy of the flywheel to the movable member. Thus, the present invention enables the provision of a novel and interesting toy. For a better understanding of the present invention, and to show how the sAme may be put into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is an exploded perspective view of a toy helicopter in accordance with the invention, Figure 2 is a vertical cross-sectional view of the toy helicopter of Fig. 1, and Figure 3 is a side elevational view of a toy aeroplane in accordance with the invention. Referring now to Fig. 1, the toy helicopter comprises a body having a left half 1 and a right half 1', the two halves being connected to one another by means of two screws passing therethrough. A flywheel is rotatably mounted in the body by means of shafts 2 which are fixed to or integrally formed with the flywheel and seat in bearings formed on the inner surface of the helicopter body. The flywheel is integrally and coaxially formed with a gear wheel 3 and comprises a left half 4 and a right half 4' which are connected by a waisted portion 9 to which a string 7 is attached and around which the string 7 can be wound. The free end of the string 7 is provided with a knob 8. A crown gear 5 and a propeller 6 are integrally formed with and connected by a bored cylindrical shaft which extends rotatably through an aperture formed in the top of the helicopter body so that the crown gear 5 is disposed inside, and the propeller 6 outside, the helicopter body. The crown gear 5 meshes with the gear wheel 3 and the string 7 extends through the bore of the cylindrical shaft so that the knob 8 is outside the helicopter body. The cylindrical shaft is held against axial movement by an outer collar which is integrally formed with the helicopter body and abuts the boss of the propeller 6 and an inner collar (not shown in Fig. 1) which is also integrally formed with the helicopter body and abuts the upper surface of the crown gear 5. In use, the string 7 is wound onto the waisted portion 9, for example by rotating the propeller 6, the knob 8 is grasped in the user's hand and the helicopter body is allowed to fall, causing rotation of the flywheel as the string 7 is unwound. When the string 7 is completely unwound the flywheel continues to rotated because of its own inertia and this causes the string 7 to be wound onto the waisted portion 9 again in the opposite direction. The toy helicopter thus repeatedly rises and falls. This motion can be caused to continue indefinitely by a skilled user, for example by tugging on the string 7 when the helicopter body is at its lowest point. In this respect the toy is similar to a conventional yoyo. However, unlike a conventional yo-yo, the flywheel also transmits rotation to the propeller 6. Turning now to Fig. 3, the toy aeroplane is constructed and operates in a manner substantially similar to that of the toy helicopter, except that the cylindrical shaft bearing the propeller 6 and the crown gear 5 extends rotatably through an aperture formed in the nose of the aeroplane body. The toy helicopter and the toy aeroplane can be manufactured from a rigid lightweight plastics material, the flywheel preferably comprising a dense material such as wood. CLAIMS

3. A toy according to Claim 2, wherein the body is hollow and the flywheel is rotata bly mounted inside the body.

4. A toy according to Claim 3, wherein the movable member is movably mounted outside the body.

5. A toy according to Claim 2, 3 or 4, which toy includes means for restraining the body from rotation about the axis of rotation of the flywheel.

6. A toy according to Claim 5, wherein the restraining means comprises the converting means.

7. A toy according to Claims 3 and 6, wherein the converting means comprises an elongate flexible member which is attached to, and can be wound around, a radially relatively reduced portion of the flywheel and extends through an aperture formed in the hollow body.

8. A toy according to any one of the preceding claims, wherein the movable member is rotatable with respect to or about the axis of rotation of the flywheel, and the transmission means comprises means for transmitting rotation from the flywheel to the movable member.

9. A toy according to Claim 8, wherein the axis of rotation of the movable member is perpendicular to, and intersects, the axis of rotation of the flywheel.

10. A toy according to any one of the preceding claims, wherein the transmission means comprises gear means.

11. A toy according to Claims 9 and 10, wherein the gear means comprises a gear wheel which is coaxially fixed to, or integrally formed with, the flywheel and a crown gear which is coaxially fixed to, or integrally formed with, the movable member and meshes with the gear wheel.

1 2. A toy according to Claims 4 and 11, wherein the crown gear is disposed inside the hollow body.

13. A toy according to Claims 7 and 12, wherein the movable member and the crown gear are connected by a cylindrical shaft which extends rotatably through the aperture and is restrained from axial movement relative to the body, the cylindrical shaft being provided with an axial bore through which the elongate flexible member extends.

14. A toy according to any one of the preceding claims, which is a toy helicopter.

1 5. A toy according to any one of Claims 1 to 12, which is a toy aeroplane.

1 6. A toy helicopter, substantially as herein before described with reference to, and as shown in, Figs. 1 and 2 of the accompanying drawings.

17. A toy aeroplane, substantially as herein before described with reference to, and as shown in, Fig. 3 of the accompanying drawings.

1 8. Any novel feature or combination of features described herein.