I was randomly reading an article on Verge the other day about the 11 millionth patent recently issued (bit of drama about it being given to a particular thing as opposed to a soy bean), and after having a bit of a browse around the USPTO website, thought I’d take a look into any Tonka patents, as you do! On the bottom of the old clutch poppers is “Patent Pend”, meaning they filed for a patent, so thought I should be able to find the original documents. After a bit of sleuthing, sure enough I think I found 2 patents, both assigned to Tonka and within a year of each other, which combined together cover the clutch popper motor as built. Regardless of what you think about patents, and whether they restrict creativity or not, they are interesting documents for whatever field of interest you may have where patents have been filed. If you have just a passing interest in flywheel motors, read some of the summary stuff further down this post, if you have deep interest, open the links, if you have no interest stop reading now or you may lose the will to live:)
Back to these 2 patents, it is a pretty unique little motor in these cars and as expected there is some fairly detailed gearing mechanism design going on there, described in great detail in the patent documents, much of which I struggle to understand:) It took the patent office 5 years to approve the second one by the looks of it. The first patent, from inventor Ohashi Yutaka, is Running toy with a flywheel – Patent 4,130,963 (here is the link to the USPTO page) , and is basically the motor that was released in the Tonka Quickshifter 1977, this provided two separate transmission lines of 9 gears (in 4 gear sets) with a slip mechanism for both engaging the axle and dropping to neutral on sudden stop without damaging the motor. Overlayed over this design was patent 4,422,263, from inventor Hiroshi Masubuchi – Gear changing mechanism for toy vehicle driving devices (here is the link to the USPTO page), filed in 1978, and it added the clutch mechanism and a small modification to the gearing.
Here are a couple of extracts from those patents as summary.
Running toy with a flywheel
The running toy with a flywheel of the invention has a toy driving unit to form a first transmission path with a first gear ratio to energize and rotate the flywheel at a high speed when driving wheels are rubbed against a floor for drive, and a second transmission path to rotate the driving wheels with the flywheel as a drive source at a speed reduced by a second gear ratio different from the first gear ratio when the drive of the driving wheels is stopped, thereby running the running toy at a speed different from the speed at time of energizing of the flywheel, a frictional rotation transmitting section provided in the second transmission path to yield a slip when the driving wheels are applied with overload.
BACKGROUND OF THE INVENTION
This invention relates to a running toy with a flywheel in which the driving wheels are driven to rotate and energize the flywheel at a high speed, and then the driving wheels are rotated making use of the rotation by inertia of the flywheel, thereby running the toy.
There have conventionally been known running toys making use of the rotation by inertia of the flywheel as stated above. However, such conventional toys have been subject to various defects. For example, a first defect is that the running toy cannot move at a speed higher than the speed corresponding to the rotating speed of the driving wheels yielded by the flywheel because the flywheel and the driving wheels are coupled securely by a set of gear train. Accordingly, when the flywheel is energized by rubbing the toy automobile against e.g. a floor surface, the running speed of the toy automobile driven by the flywheel is equal to or lower than the moving speed of the toy automobile at energizing of the flywheel.
Meanwhile, a second defect is that as the flywheel and the driving wheels are coupled securely by the gear train, so, when the driving wheels are stopped while the toy automobile is running or applied with overload, the rotating parts on their relevant portions may be distorted by the large energy of rotation possessed by the flywheel or the teeth of the gears used may be broken.
A first object of this invention is to provide a running toy with a flywheel free from the aforesaid defects possessed by the conventional running toys with flywheel in which the driving wheels start rotation at a speed different from the rotating speed of the driving wheels at energizing the flywheel, thus allowing the running toy to start running at a speed different from the moving speed equivalent to the rotating speed of the driving wheels at energizing of the flywheel.
The running toy with the above-mentioned construction of this invention may be run at a speed different from higher lower speed than the energizing speed when the running toy is rubbed against e.g. a floor surface by selecting the first and second gear ratios properly. Further, by providing the second transmission path of the running toy with a rotation transmitting section employing a friction coupling, the large torque, which may be produced according to the high-speed rotation of the flywheel when the driving wheels of the running toy are applied with overload or stopped, can be dissipated through the friction coupling, thereby avoiding damage to the relevant portions.
It then goes on to describe, in intricate detail, the relationship between the 9 internal gears and the 2 primary transmission paths. Read at your own leisure if you are super interested in low level gearing and flywheel inertia mechanics:)
Gear changing mechanism for toy vehicle driving devices
A toy vehicle is disclosed including a gear changing mechanism for use in conjunction with a flywheel driving device. The mechanism comprises a gear changing lever pivotally mounted to a frame by means of a pin. The lever is biased in one direction by means of a first spring member to hold the axle of an idle gear in engagement with one end of an elongated opening formed in the frame. The gear changing lever is adapted to pivot by a depressing action against the force of the first spring member to disengage the idle gear axle from the one end of the elongated opening so as to allow a second spring member to urge the idle gear axle against the other end of the elongated opening.
And that, in summary, is way more than I ever thought anyone ever needed to know about flywheel motors with clutch mechanisms, of which of course, this is the only known example:)