Light weight helicopter

• US 20050098682A1
• Filed: 02/07/2001
• Published: 05/12/2005
• Est. Priority Date: 02/07/2001
• Status: Abandoned Application

• Current Assignee: Council of Scientific & Industrial Research
• Original Assignee: Council of Scientific & Industrial Research
• Inventors: Pai, Bhaskar Ramchandra
• Application Number:
  US10/380,904
• Publication Number:
  US 20050098682A1
• Time in Patent Office: Days
• US Class Current: 244/17.11
• CPC Class Codes: B64C 27/10 arranged coaxially
• CPC Class Codes: B64C 31/028 Hang-glider-type aircraft; Microlight-type aircraft
• CPC Class Codes: B64C 39/026 for use as personal propulsion unit

Abstract

The present invention relates to a lightweight helicopter, comprising of a rotary wing (1) unit and a frame assembly (2), the rotary wing consists of an engine (3) with a primary gear box (7), mounted below a keel post (8) and the keel post attached to a triangular control frame (28), the base of which forms the control bar (29), and is also provided with a tail plane (12) having one or more vertical articulable flaps (34). A secondary gearbox is provided with means capable of transmitting the rotary movement of the said engine to two horizontal rotors (9, 10) capable of pitch change. The rotary wing unit is suspended by means to a frame assembly having means (47) for pilot seating, landing gear (46) and provided with means for control of the engine, rotors, tailplane and landing gear.

Claims

1-8. -8. (canceled)

9. A light weight helicopter which comprises a rotary wing unit (1) having an engine (3) with a primary gearbox (4) being connected through flexible coupling (5) and centrifugal clutch (6) to a secondary gear box (7), the said engine, the primary and the secondary gearbox assemblies being mounted below a horizontal keel post (8) using mounting means (20), the said keel post being also rigidly attached to a triangular control frame (28), a base portion of which forms a control bar (29), the said keel post being fixed to a fuel tank (11) and being connected to said engine, the said keel post being also provided with a tail plane (12) having one or more articulated vertical flap (34) capable of being articulated by cable means (40), the said secondary gearbox being provided with freewheeling clutch (18), pinion gear (17) and bevel gears (15&

16) capable of transmitting the rotary movement of the said engine to two contra rotating vertical concentric shafts (13&

14) each of which being fixed by pitch bearing (22) on the teetering plates (23) and teetering hinges (24) to horizontal rotors (9, 10), the said horizontal rotors having at least two rotor blades of airfoil cross section (21) capable of pitch change through rotary movement of pitch horn (25), the said pitch horn on each rotor blade being connected to star and turnbuckle mechanism (26) and stationary control fork (19), the said rotary ring unit being attached to a tricycle assembly (2) through a landing gear (46) and provided with means for control of the said engine, rotors, tail plane and landing gear, said tricycle assembly having a triangular frame composed of a rear beam (35), a horizontal beam (36) and a front tube (37), the said horizontal beam supporting a front fork (38) in a pivot, the said front fork being provided with footrest (39) for the pilot, the said front fork being attached to cables (40) linking to the said articulated vertical flap, such that the rotation of the said front fork resulting in the hinge movement of the flap, the said horizontal tube also supporting a plurality of landing gear tubes (41), which are kept in position trough tensioned cables (43), (44) and (45), the said landing tubes and the front fork supporting landing gear (46), the pilot being seated in a seat (47) fixed on the said horizontal beam and secured firmly to the seat through seat belts (48).

10. A lightweight helicopter as claimed in claim 9 wherein, the engine used is selected from a 2-stroke reciprocating petrol engine, or a Wankel rotary engine of high power to weight ratio as herein described.

11. A light weight helicopter as claimed in claim 9 wherein, a triangular control frame articulates the rotary ring unit through a control bar held by the pilot.

12. A light weight helicopter as claimed in claim 9 wherein, the means for activating the change in rotor blade mean pitch is a rotatable twist grip located on the control bar and controlled by the pilot.

13. A lightweight helicopter as claimed in claim 9 wherein, the landing gear is selected from tyred wheels, skids or floats.