Patent Application
20140323009
1. Technical Field
The present invention relates to radio control toy helicopter models. More particularly, it relates to a radio control toy helicopter model having protective rings positioned at the outer rotational circumference of corresponding propellers. The protective ring can be installed on remote control toy helicopter for safety purposes without adversely affecting the flight performance.
2. Description of Related Art
Conventional radio control toy helicopters are normally designed to have dual main rotors or propellers at two vertical levels to achieve stable flight. Generally, one of the rotors or propellers turns in one direction, and the other rotor or propeller turns in the opposite direction to cancel the torque steer effect that a single rotor or propeller inherently produces.
The rotors or propellers have to be rotated at very high speed to achieve flight, so operation of conventional remote control toy helicopters is sometimes dangerous. If the helicopter hits a person, it may cause injury from the impact of the rapidly spinning propeller blades. Also, objects nearby may be damaged if they are hit by the spinning rotors of conventional remote control toy helicopters. In addition, the light materials used to form the propeller on top of the conventional remote control toy helicopter may be damaged or break upon impact, necessitating its repair or full replacement with a new propeller.
Adding the protective ring on the propeller itself is preferable for safety purposes. However, if the protective ring is firmly fixed onto the ends of propeller blades as an integrated part, the helicopter will lose stability in its flight and crash down to the ground because of “precession.” Precession is defined as a change in the orientation of the rotational axis of a rotating body. The protective ring of the present embodiments is not firmly fixed onto the tips of the propeller blades, but rather pivotally connected to the ends of the propeller blade. The ends or tips of the propeller blades are connected to inner side of the protective ring at its pivoting points. The pivot points are aligned with the longitudinal axis of the attached propeller. Therefore, the protective ring is capable of pivoting or tilting freely at the pivot points, independent of the tilting angle of the propeller blade. The protective ring is able to restrain the “precession” and provide stable flight to the remote control toy helicopters, in addition to protecting the propeller.
These and other aspects are achieved in accordance with an implementation of the invention, where the helicopter includes a helicopter body having a rotating shaft. A propeller is connected to the shaft, and is configured to rotate in a first direction about an axis defined by the shaft. The propeller has opposing ends and a longitudinal axis transverse to the shaft axis. A protective ring has pivot points configured to connect to the protective ring to the opposing ends of the propeller. The protective ring rotates with the propeller and is capable of pivoting about the longitudinal axis of the independent of the tilt angle of propeller.
According to another implementation, the helicopter includes a first propeller connected by a shaft to a helicopter body, and being configured to rotate in a first direction about an axis defined by the shaft. The first propeller has opposing ends and a longitudinal axis transverse to the shaft axis. A second propeller is connected to the shaft above the first propeller, and is configured to rotate in a direction opposite the first direction about the shaft axis. The second propeller has opposing ends and a longitudinal axis transverse to the shaft axis. A first protective ring is connected to the opposing ends of the first propeller. A second protective ring has pivot points configured to pivotally connect the second protective ring to the opposing ends of the second propeller. The second protective ring rotates with the second propeller and is capable of pivoting about the longitudinal axis of the second propeller independent of a tilting angle of the second propeller.
According to yet another implementation, the helicopter includes a helicopter body having a rotating shaft. A first propeller is connected to the shaft, and is configured to rotate about an axis defined by the shaft in a first direction. The first propeller has opposing ends and a longitudinal axis substantially transverse to the shaft axis. A second propeller is connected to the shaft and positioned above the first propeller. The second propeller is configured to rotate in a direction opposite the first direction about the shaft axis. The second propeller has opposing ends and a longitudinal axis substantially transverse to the shaft axis. A first protective ring has pivot points configured to pivotally connect the first protective ring to the opposing ends of the first propeller. The first protective ring rotates with the first propeller and is capable of pivoting about the longitudinal axis of the first propeller independent of a tiling angle of the first propeller. A second protective ring is fixed to the opposing ends of the second propeller.
The following detailed description of the preferred embodiment is accompanied by drawings in order to make it more readily understandable. In the drawings wherein like reference numerals denote similar elements throughout the views:
The present embodiments provide a propeller assembly that includes protective rings around the propellers that provide protection during a collision, for people and objects nearby as well as for the propellers themselves. The protective rings are attached to the propellers at pivot points, allowing the rings to rotate relative to the propellers and thereby prevent the precession that would result from fixed rings.
Precession occurs when a spinning body—in this case, the propellers of the helicopter—experiences a torque. In the case of a propeller with a fixed ring, the system will act like a top or gyroscope, causing the central axis of the propeller to rotate through space. This precession causes a continuous change in the direction of thrust provided by the propeller, making the helicopter impossible to control. However, by introducing the ability for the protecting rings to rotate around an axis defined by the propellers, the torques caused by gravity can be localized to the rings, such that the propellers themselves do not precess.
Referring now to the drawings and initially to
The stabilizer 106 can be installed either above or below the first propeller 102 and can is connected to the top propeller 102 through the links 108. The stabilizer 106 is able to control the tilted angle of the first propeller 102. Notably, the length of the stabilizer 106 is shorter than the length of the propellers 102 and 104 such that the stabilizer does not need a ring of its own—the protective rings 112 and 114 are attached their respective propellers provide the intended protection. As will be shown below, however, the stabilizer 106 may also include a protective ring as well.
The first propeller 102 can be tilted in connection with movement of the stabilizer 106, but in the present embodiment the second propeller 104 cannot be tilted. Pivot points 116 are added to the protective ring to accept the ends or tips of the blades of the second propeller 104 or of both the first and second propellers 102 and 104. The protective rings 112 and/or 114 are configured to pivot freely or independently without being affected by the tilted angle of the connected propeller.
As will be evident, the propellers 112 and/or 114 include a longitudinal axis A along which the pivot points at the opposing ends of the respective propellers is aligned.
In the illustrated embodiments, the protective rings 112 and 114 are attached by a pivot point 116 that includes, e.g., a receiver 118 on the propeller and a rivet 120 that connects to the receiver 114 by passing through a receiving hole 116 in the protective rings 112 or 114. It is contemplated that those having ordinary skill in the art would be able to devise any appropriate pivot or hinge mechanism to connect the protective rings 112 and 114 to the propellers 102 and 104, respectively. For example, the rivet 120 may be replaced by a post formed integrally with the propeller. It should be noted that the range of angular motion permitted to the protective rings 112 and/or 114 should be limited to prevent them from interfering with the blades of adjacent propellers.
According to another embodiment, one of the protective rings 112 or 114 can be unmovably fixed to the propeller. In this embodiment, the protective ring may be formed integrally with the propeller itself using, e.g., injection molding.
Adding the movable protective rings on both the first and second propellers 102 and 104 is preferable. However, in one alternative embodiment, the movable protective ring 114 can be installed only to the second propeller 104, which cannot be tilted, and a fixed protective ring 112 can be attached to the first propeller 102. The first propeller 102 can be tilted in connection with the stabilizer 106.
Referring now to
Referring now to
Referring now to
While there have been shown, described and pointed out fundamental novel features of the present principles, it will be understood that various omissions, substitutions and changes in the form and detail of the methods described and devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the same. For example, it is expressly intended that all combinations of those elements and/or methods steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the present principles. Moreover, it should be recognized that structures and/or elements and/or methods steps shown and/or described in connection with any disclosed form or implementation of the present principles may be incorporated in any other disclosed, described or suggested form or implementation as a general matter or design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.
This application claims priority from U.S. Provisional application Ser. No. 61/815,315, filed on Apr. 24, 2013, the entire content of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61815315 | Apr 2013 | US |
