JPS591639B2 - Vibration suppressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to helicopter vibration isolation, preferably a structure that provides isolation while operating in a focused rotor mode.

The vibrations of a helicopter are particularly severe in a two-blade system.

Rigid vibration input through the pylon to the fuselage is caused by variations in the force applied to the rotor of the lift device.

Proposals have been made to try to dampen or eliminate unwanted movements of the torso through the strength of the vibrations.

U.S. Pat. No. 3,845,917 describes a system in which a lifting device is connected to a load-bearing fuselage only at its vibration node points (hereinafter simply referred to as vibration node points).

The transmission of vibrational energy from the lifting device to the suspended fuselage at the node point is thus minimized or significantly reduced.

The present invention is an improvement on the device described in U.S. Pat. No. 3,845,917.

It is an object of the invention to provide focused rotor operation while minimizing weight and space requirements.

U.S. Pat. No. 3,845,917 describes conditions for locating vibration nodes outside the fuselage section spanned by each drive linkage.

This arrangement reduces the space requirements of the device.

The present invention provides a novel helicopter system having a multi-blade main rotor assembly having a nodal module containing a beam driven in response to a strike force on the blades.

The fuselage is connected to the beam only at vibration nodes.

The beam includes two rigid arms extending toward each other from each node point.

Multiple layers of flexible beam sections interconnect each arm member to accommodate beam curvature.

Next, a rigid member is attached to each arm member in supporting relationship from the lifting device at a drive point intermediate the points of each node.

Each rigid member preferably connects the lift device to the fuselage in a focus rotor geometry relationship.

Embodiments of the vibration suppressing device of the present invention will be described in detail below with reference to the accompanying drawings.

Pylon or helicopter tower pillar 1 as shown in Figure 1
0 extends upward from the drive power transmission device 11 .

A multi-blade helicopter rotor is indicated by the vane portion 12.13.

The transmission 11 is connected by a link 14.15 to a pin joint 16.17 of a nodalized beam 18 (hereinafter simply referred to as beam).

Beam 18 is connected to fuselage mounts 20, 21 by pins.

Beam 18 consists of three main parts.

That is, two rigid arm members 18a. 18b is the mounting tool 20
．． It extends from 21.

Further, the intermediate beam section 18c has a somewhat high elasticity and is fixed to each arm member 18a, 18b.

Link 14.15, pin joint 16.17 and beam 1
8 constitute a joint module.

As the structure of FIG. 1 vibrates in response to the forces indicated by arrows 22, these forces are applied through column 10 to transmission 11 and then through each link 14, 15 to composite beam 18.

The beam 18 oscillates in its central portion which is subjected to periodic beam bending effects.

When properly configured, beam 18 attaches to fixture 2.
Since each point connected to 0.21 vibrates as a node of vibration, the motion represented by arrow 22 is the same as that of fixtures 20, 2.
It does not join the fuselage to which 1 is attached.

The present invention is particularly directed to suitable beam structures and linkages in combination with such beam structures which provide focused rotor operation and which apply torque from the rotor attachment to the fuselage.

In FIG. 2, the tower column 10 and the transmission device 11 are shown in an exploded view.

The connection between the transmission 11 and the fuselage is provided by a pair of composite beams.

The first beam 30 comprises rigid end beams 3L32 interconnected by a flexible central beam section 33.

The flexible central beam section 33 is the end beam 31.3.
In the cup-shaped end 34.35 of 2 there is an opening.

The end of the end beam 31 opposite the flexible central beam section 33 is connected to an attachment 37 fixed to the fuselage by means of a pin 36.
It is connected to.

The end of the end beam 32 opposite the flexible central beam section 33 is connected to a fixture 39 by a pin 38.

The fitting 39 is fixed to or forms part of the fuselage.

A rigid link or arm member 40 extends from a pin 41 of the end beam 31 to a pin 42 fixed to the transmission 11.

Rigid links or arm members 43 similarly connect end beams 3 to
It is connected to the second pin 44 and is attached to the transmission device 11 by a pin 45.

Similarly, the second beam 50 has a rigid end beam 51.5.
2 and a flexible C soft beam section 53 interconnecting the ends thereof.

A second beam 50 is connected to each fixture 57,59.

Links or arms 60, 63, respectively, serve to connect the end beams 51, 52 to the transmission 11.

The links 40, 43 are inclined so that their upper ends extend toward each other, and the intersection of their center lines is a straight line 7.
It should be along the line 0.

Similarly, the center line of each link 60, 63 intersects the straight line 70.

The straight line 70 passes through the center of vibration due to the shock of the column 10, thereby minimizing the pitching that would normally occur in the fuselage if the straight line 70 were displaced from the center of vibration due to the shock of the column 10.

The links 40, 60 are tilted relative to each other so that their respective center lines intersect the straight line 71 below the assembly.

Similarly, each link 43.63 intersects on straight line 71.

A straight line 70 extends across the fuselage.

Straight line 71 extends in the longitudinal direction of the fuselage. Straight line 71 passes through the center of gravity of the aircraft.

That is, each beam 30.50 with a nodal point makes it possible to attach the column 10 and the transmission 11 to the nodal point while retaining the use of a focusing rotor system.

In this embodiment, a pair of torque links 80, 81 are connected to the lower part of the transmission 11 by suitable pins and extend generally along a plane perpendicular to the axis of the column 10.

Link 80 connects to toggle 82.

The toggle 82 is connected by a link 83 to an elastomeric mounting member 84 secured to the fuselage.

Similarly, link 81 is connected to toggle 85.

Toggle 85 links 8 to elastomeric body member 87
It is connected by 6.

Each toggle 82,85 is then interconnected by a link 88.

The torque in the horizontal plane that occurs in the tower column 10 is the link mechanism 80-
88, the effect of each beam 30.50 on producing a nodal point is transmitted unchanged to the fuselage.

The rigid movement indicated by the arrow 22 present in the transmission 11 is caused by each link 40, 43, 60, 63 in each beam 3.
Add to 0.50.

Because the central beam section 33 and the soft beam section 53 are curved, points such as pin 36 are at nodes of vibration and little, if any, of the motion indicated by arrow 22 is transmitted to the fuselage.

The structure of beam section 33 according to a preferred embodiment of the invention is shown in FIG.

In this embodiment, the cup-shaped end 35 of the beam section 32 serves to accommodate one end of the beam section 33.

The cup-shaped end 35 is provided with a rectangular metal lining 90.

Beam section 33 consists of ten metal layers, such as layer 91.

Between each adjacent surface of each layer 91 is a layer 9 of elastomeric material.
2 is glued together.

That is, the beam section 33 includes each adjacent metal layer 91.
In between is an elastomeric adhesive beam with layer 92.

In this way, the beam can be bent without mutual displacement due to friction of one metal surface.

In the curved configuration, the ends 93 are stepped to transmit shear forces to the elastomeric layer 92.

A lower metal layer 91 is adhered to the upper surface of a pillow block 94 of elastomeric material.

The lower surface of pillow block 94 is adhered to the inner surface of cup-shaped end 90.

The upper metal plate 95 of the beam section 33 is glued to the underside of a similar upper pillow block 96.

The top surface of the pillow block 96 is made of product name Teflon (TEEL).
ON) and is not bonded to the cup-shaped end 90.

In this way the end 93 of the beam section 33 has a cup-shaped end 9
0, but allows substantial relative movement in response to bending forces at the top of the cup-shaped end 90.

In one embodiment of the invention, each beam arm 31.32 was 16.8 inches long.

Beam section 33 was 5 inches long.

Beam sections 33 are each 0.1 inch thick and 2.0 inch wide.
It was made from layers 91 and 95 (seven bar members) with a length of 10 inches.

The elastomeric layer sandwiched between the metal layers 91,95 was made of rubber and had a thickness of 0.03 inches in the unstressed state.

The composite beam, consisting of each beam arm 31, 32 and beam section 33, was driven once with pins 41, 44 by links 40° 43 at each point 34 inches apart from each other.

The spacing between each pin 38.36 in FIG. 2 was 38.5 inches.

- Angle a in Figure 2 was 130°.

The angle in Figure 2 was less than 30°.

In the modification shown in FIG. 4, the beam is provided with a loading section to change its natural frequency and further shorten the distance between the nodal points 100, 101.

This beam has a more flexible central beam section 10
It consists of rigid end beams or beam arms 102, 103 interconnected by 4.

The cutout portion of the beam arm member 103
3 shows the extension of the central beam section 104 to the cup-shaped end 105 of FIG.

Arm member 106 attaches to beam arm member 103 at its cupped end 10.
It is fixed near 5.

The load applied by the arm member 106 is applied to the beam arm member 102,
Changing the frequency of the beam section 104 and the arm member 103,
The distance between the node points 100 and 101 can be shortened.

The end of the beam arm member 103 opposite to the beam arm member 102 is connected to a fixture 107 fixed to the body by a node 100, ie, a pin.

The end of the beam arm member 102 opposite to the beam arm member 103 is connected to a fixture 108 by a node 101, that is, a pin.

The fitting 103 is fixed to or forms part of the fuselage.

A rigid link or arm 109 extends from pin 110 into beam arm 102 .

Link or arm 111 is similarly attached to beam arm 103 by pin 112.

FIG. 5 shows the application of the invention to a single beam unit with nodes.

The column 10 and the transmission 11 are shown in broken lines.

The connection between the transmission 11 and the fuselage is by a single composite beam.

This beam has a more flexible central beam section 123.
It consists of rigid end beams or beam arms 121, 122 interconnected by.

The central beam section 123 includes each beam arm member 121, 12.
The cup-shaped ends 121a, 122a of the two are covered.

The ends of the beam arm members 121 opposite the beam arm members 122 are connected by suitable pins to links 125 and 126 respectively attached to the fuselage.

Similarly, the end of the beam arm member 122 opposite to the beam arm member 121 is connected to a link 127 attached to the body, respectively.
128 by a suitable pin.

A rigid link or arm 129 is connected to the beam arm 121 by a suitable pin and extends to a pin 130 fixed to the transmission 11.

A link or arm 131 is likewise attached to the beam arm 121 by a suitable pin and extends to a pin 132 fixed to the transmission 11.

Similarly, the rigid risks or arms 133, 134 serve to connect the beam arm 122 to the transmission 11.

In this embodiment, a single torque link 135 is connected to the lower portion of the transmission 11 by a suitable pin.

Links 135 connect to elastomeric attachments 136 and 137 attached to beam arms 122.

The end of the beam arm member 121 opposite to the beam arm member 122 is connected to a rigid link 1 fixed to the body by a suitable pin.
It is connected to 38,139.

The end of the beam arm member 122 opposite to the beam arm member 121 is connected to a rigid link 1 fixed to the body by a suitable pin.
It is connected to 40.

Torques in the horizontal plane that occur in the column 10 are transmitted to the fuselage by the links 138 and 140 without altering the action of the nodes on the beam 120.

That is, according to the present invention, in response to a vertical force generated by a lift device including a multi-blade helicopter main rotor device and a wing,
A helicopter with a nodal module containing a driven beam has a fuselage unit connected to the beam only at the nodal points of vibration along the beam.

The connection between the lifting device and the fuselage includes two rigid arms forming a beam and extending toward each other from each node point.

A multilayer flexible beam section interconnects each arm member to accommodate the beam curvature of the flexible section.

Each arm member is fitted with a rigid member at each drive point between each nodal point in supporting relationship from the lifting device.

In a preferred form, the beam has an elastomeric multilayer intermediate section embedded with a plurality of longitudinally extending spring plates parallel to each other for controlling the elastic contact of the beam.

It goes without saying that the present invention can be modified in various ways without departing from its spirit.

[Brief explanation of the drawing]

Fig. 1 is a diagrammatic front view showing the relationship between the articulated lift module and the fuselage of the focus rotor of a helicopter, Fig. 2 is a perspective view of one embodiment of the vibration suppression device of the present invention, and Fig. 3 is a FIG. 4 is an enlarged vertical cross-sectional view of a part of the beam of the vibration suppressor shown in FIG. 4. FIG. 4 is a partially cutaway perspective view of one modification of the beam shown in FIG. 2, and FIG. It is a perspective view showing the application of the method to a single beam node forming unit. 10... Column, 11... Transmission device, 3
0... Beam, 31, 32... Beam arm member, 33... Beam section, 34, 35...
...End, 36, 38...Pin (node point)
, 40.43... Link (member), 41.44
...Pin (driving point).

Claims (1)

[Claims] 1 Used in a helicopter equipped with a lifting device having a multi-blade rotor system driven by a pylon from a transmission device, and a joint module connected to the fuselage and driven by the vertical force generated by the blades. In the vibration suppressing device, (a) end beams extending vertically toward each other from a pair of front pivot nodes and a pair of rear pivot nodes provided front and rear with a spaced interval laterally on the fuselage; (b) a flexible beam section interconnecting opposite ends of the end beams so that the end beams oscillate vertically; and (c) one side of the transmission. a pair of rigid arm members having lower ends pivotally connected to longitudinally spaced nodes on the end beam; (e) a pair of rigid arm members whose lower ends are pivotally connected to vertically spaced nodes provided on the transmission beam; longitudinally tilting the rigid arm members toward each other such that the axis of the rigid arm members intersects a transverse line passing through the center of vibration due to the impact of the lifting device; pivot means for connecting the upper ends of the arm members of the transmission device to the transmission; (f) the axes of the pair of rigid arm members on the other side of the transmission device; pivot means for coupling the upper ends of the arm members to the transmission with their axes tilted longitudinally towards each other so as to intersect a transverse line; tilting the two rigid arm members from side to side such that the axes of the two rigid arm members located at the rear intersect a longitudinal line passing through the center of gravity of the aircraft below the lifting device; A vibration suppressing device characterized in that the two rigid arm members are inclined from side to side so that their axes intersect with the vertical line below the lifting device.