Can the patent of Dyson's red curling stick be circumvented?

On October 10, 2018, Dyson released a curling hair stick called Dyson Airwrap Styler, which set off a upsurge of screen brushing and buying in China. Dyson, a small home appliance brand from the United Kingdom, has quickly become popular in China in recent years and has become synonymous with fashion and high technology. However, this newly released curling rod also changes the style of the traditional curling rod and uses the swirling air flow technology to realize automatic curling. Consumers only need to place a strand of hair next to the curling rod, and the air flow generated by the curling rod can automatically absorb the hair to the curling rod and rotate it several times to complete the curling.

Dyson officially announced that this curling stick has been developed for 6 years, with more than 230 engineers participating in research and development, and more than 100 million yuan has been invested in research and development. Airwrap Styler uses a bold design that uses the "Coanda effect" generated by the high-speed, high-voltage Dyson V9 electric motor to achieve a curling effect. The so-called "Coanda effect" refers to the tendency of fluid (air flow or water flow) to leave the original flow direction and flow with the protruding surface of the object. At present, in addition to its own function as a curling iron, this curling iron can also be converted into a hair straightener and a hair dryer. The full set price is about 3800 yuan.

In order to prevent competitors from imitating, Dyson has also made great efforts in the patent layout. From curling iron, hair straightener connector to internal motor, Dyson has applied for dozens of patent families, with more than 200 patent applications. At present, more than 100 patents have been authorized. Among them, there are 18 patent families and more than 100 patent applications for the connector of the light curling iron.

The core technology of Airwrap is to use the curling iron of whirling air flow. The key component is to form a certain angle at the air outlet of the curling iron, so that the air ejected from multiple outlets just forms a whirling, and then a strand of hair is placed beside the curling iron. These whirling air flows will drive the hair to rotate.

Among these patents, the most important invention is the invention with priority on March 20, 2014, and its US patent publication number is US20150265023A1. This patent has also applied for invention and utility model in China. At present, the patent's family has been authorized in the United Kingdom, Japan and Singapore. The authorized claim 1 is as follows:

An attachment for a hand held appliance, characterized in that the attachment comprises a body having a wall, a fluid inlet at one end of the wall and a fluid outlet through the wall, wherein the fluid outlet comprises at least one slot extending along the wall, and wherein the at least one slot is formed by the overlap of a first end of the wall and a second end of the wall.

The core component of the claim is a hollow tube body with a plurality of slits on the surface, and hot air enters through the openings and then comes out from the slits. The ingenuity of the invention is that the two sides of the air outlet are made to overlap up and down. Without this technical feature, rotating airflow cannot be formed, which is essentially no different from a hair dryer. It is precisely because of such technical features that when the air comes out of the gap, there will be a deflection angle. The air is directed to the pipe wall, forming a Coanda effect on the pipe wall. The airflow coming out of the gap is like being adsorbed on the pipe wall. The airflow coming out of each gap seems to be adsorbed by the pipe wall, forming a rotating airflow around the pipe wall as a whole. When a strand of hair is used to approach the rotating airflow, the rotating airflow will curl the hair like a miniature tornado, because the rotating airflow will continue, and the hair will be wound into a circle shape, and finally the curl will be completed.

The prior art closest to this invention at present is a Chinese patent application, published as CN1061901A, filed in 1991, and a U. S. patent application, published as US5868148A, filed in 1998. The main technical solution of the CN1061901A patent is a hair curler with a blow-drying function. This hair curler is also a hollow tube body, and the surface of the tube body also has a gap as an airflow outlet. However, this gap is only a general air outlet and has no guiding effect on the air flow. The air flow from the gap cannot be blown to the pipe wall and is blown straight to the distance, thus forming no effective Coanda effect. No rotating air flow can be formed around the curling iron, and there is no automatic curling effect. Another very close point in the patent is that the tube body is combined and consists of several overlapping tubular bodies, which can change the thickness. This shape is basically the same as the structure of Dyson's core invention point. However, CN1061901A the purpose of this overlapping structure is to change the thickness, it solves different technical problems, and in the use state, the structure will change and cannot form a rotating airflow.

The main content of the US5868148A is a hair dryer with air guide blades. The basic structure is similar to that of the present invention. The surface of the tubular body forms a gap to blow out the air flow, and a guide is arranged at the gap opening, which seems to be able to form a rotating air flow. However, the overlapping air outlet in the present invention is not disclosed, and the purpose is also different.

Therefore, these two closest comparison documents lack the characteristics that allow the airflow blown out of the gap to form a Coanda effect, forming a rotating airflow around the pipe wall. There is also a prior art in the field of hair dryers that utilizes the Coanda effect, but whether it can be used to challenge the creativity of the present invention in combination with these two comparative documents is estimated to be the point of contention whether the patent can be authorized or invalid in other countries.

As to whether the claims of this patent can be circumvented, in fact, US5868148A have hinted at a solution. The core of this invention is to realize automatic curling through rotating airflow. The key to forming Coanda effect in gap airflow is that the blown wind needs to be guided to the pipe wall. In the present invention, it is realized by overlapping end faces, but a similar effect can be achieved by a US5868148A structure without overlapping. Of course, if the invention is improved, there are more feasible solutions, because avoiding the technical feature of "overlap" is not as difficult to avoid as the functional limitation of the claim.

Source: "Rational Analysis, Can the Patent of Dyson's Red Curling Wand Go Around?"