I was on holiday recently when I noticed a street vendor selling those pesky weasels which move back and forth as they try to manoeuvre a ball. I picked up a box, saw that it was called the “Weazel Ball®” (not “weasel”), that it was made in China, and that it claimed to be patented.

The ® suggested a registered trade mark. It is a huge help when a name is given as a search can be made for it to identify a manufacturer, although sometimes the invention comes from someone who has licensed the rights. It can also be looked for in Google Images to see if it looks like what you imagined. Sometimes the site containing the image has extra, useful information.

Neither the British nor the Community databases list any such trade mark. The official American site TESS, though, does. It gave a lot of information. It was a “battery operated motorized toy featuring a plush animal tail which when operated, gives the impression of an animal chasing and jumping a ball”, which had first been used in commerce in June 1995. It had been applied for as a trade mark in November 1995 by Dah Yang Toy Industrial Company, a Taiwanese firm.

With this hint I looked up the company to see what they had patented. 14 American patent documents were listed on Esp@cenet®. Several of these involved rolling movement, and one (by luck) actually showed the weasel in action as a representative drawing.
This was US 5934968, “Random moving toy simulating pursuit by toy animal”, which had been applied for in December 1995, my Patent of the Month.

As the patent explains, what is actually happening is that a motor inside the ball (which is attached to the weasel) is providing the motion by using an “eccentric” movement. This means that it constantly and randomly overbalances, and hence moves. A small battery using direct current provides the power.

A big problem in looking up such inventions is that often the name is not known. In this case, the search report on the front page of the patent document listing earlier similar “prior art” cites web sites and trade literature with the names Cat Trap, Crazy Critter, Squiggle Ball, Motor Balls™ and Wild Tail Pet Toy. They sound as if they could also be names for the toy.

The invention was only patented in the USA and in Germany. French patent 2742349 seems to be a slight variation on the toy by the same inventor and company. Hence it is apparently free to use in most of the world.

There is one sting in the tail in identifying this patent with the invention. When I did a little research on a business news database, the only mention I found of Weazel Ball was from the Wall Street Journal in April 1996.

It does not mention any patent or trade mark rights, but attributes the invention to a Samuel Su, who was new to me, and Toy Wonders, a Taiwanese company. Neither Su nor that company are credited with any inventions according to Esp@cenet. This is very mysterious, but the stories the article gives about the origin of the toy are intriguing.

Originally they simply had a motor-driven ball. Hoping to attract attention to the device at an international toy fair in 1994, Mr. Su's nephew placed the ball in a paper bag and let it loose on the floor. The noisy, rolling bag turned heads, he said. "So then I decided that it should look as if an animal was in the bag." At first it was a raccoon, but then the toy was adapted by removing the bag and using a weasel. Attaching the nose to the ball was the hard part, but Su’s wife finally came up with a solution. She was at a department store and saw tags hanging from clothes, and decided that the same plastic could be used to string the nose of the weasel through a hole in the plastic. 
I certainly remember seeing a version where the ball and the weasel’s head were inside a paper bag. I found that more enigmatic than the non-paper version, though it does lack the cute face, admittedly.