JP2915577B2 - Helicopter - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a helicopter having low vibration and noise in a cabin and excellent ride comfort. More specifically, the present invention relates to a helicopter having a floating cabin.

BACKGROUND ART Conventionally, various vibration reduction devices have been put into practical use or developed to reduce helicopter vibration. The largest source of vibration in the helicopter cabin is the rotation of the main rotor. Normally, the rotation speed of the main rotor (main rotor) is about 4 to 6 per second. However, when the rotor blades are normally adjusted and balanced, the vibration of this rotation speed (one rotation per rotation) (Referred to as "1 / rev" in meaning)
As such, it does not pose a problem to the passenger. What is most problematic is a vibration called a "high frequency vibration" of a vibration frequency N / rev obtained by multiplying the vibration 1 / rev of the rotation speed by the number N of the rotor blades. Normally, the number of rotor blades is four (N = 4), so N / rev is 15 to 20 Hz. Therefore, to reduce the helicopter vibration,
The vibration level of the vibration frequency N / rev of a helicopter that does not apply any vibration reduction device is 0.5G (G is the unit of vibration acceleration). ). This vibration level is obviously large enough to cause discomfort to the occupant, and some measures for vibration reduction are required.

FIG. 19 is an explanatory diagram of a conventional helicopter vibration reducing device. One of the main causes of the excitation force due to the rotation of the main rotor is in-plane and out-of-plane vibration of the blade 51. For this reason,
A vibration absorbing device using the pendulum 53 is attached to the vicinity of the root of each blade 51 or to the rotor head 52 to reduce the vibration of the blade 51. Also, according to the vibration frequency N / rev, the spring 55
A vibration absorbing device in which the weight and the weight 54 are adjusted is attached to the body to reduce the vibration of the body.

However, in the conventional helicopter vibration reducing apparatus as described above, the pendulum 53 and the weight 54 having a considerable weight are required to achieve a large vibration reducing effect, and the air resistance is also increased. In addition to these, various helicopter vibration reduction devices have been developed, but any of those currently in practical use have a small vibration reduction effect. An ideal vibration reduction device that can be expected to have a large vibration reduction effect has many disadvantageous elements such as system complexity or a large power source for control.

To design a more comfortable helicopter,
Main vibration frequency N / re in helicopter cabin
not only greatly reduce the vibration level of v and further reduce the noise transmitted through the aircraft, but also achieve a large vibration reduction effect without complicating the structure of the vibration reduction device,
Does not increase static movement while insulating vibration, does not impair flight safety, does not require large power for control, always has good vibration reduction effect even when flight conditions and cabin weight change Is required to be satisfied.

Under such circumstances, a helicopter having a relatively simple system of vibration reduction device is disclosed in US Pat. No. 3,857,534.
And British Patent 1,368,187. All of these inventions are related to the same inventor, and separate the floor of the helicopter cabin from the body of the helicopter and connect this floor via a two-stage cantilever to the nodal point of vibration of the body of the body.
The vibration is prevented from being transmitted to the cabin by being supported by.

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a low-vibration helicopter that is easy to put into practical use.

Therefore, the present invention provides a helicopter employing the following configuration.

(1) a main rotor having a plurality of blades, an engine for driving the main rotor, an airframe main body including the engine therein and having a cabin support, a spring and an actuator installed in the cabin support, A cabin supported by the cabin support via the spring and the actuator, and a body body including a cabin support in parallel with the actuator so as to limit an interval between the cabin support and the cabin due to vibration to within a certain range. A stopper provided between the cabin, a vibration state quantity sensor provided in the cabin, and a vibration damping signal which receives an output of the sensor and inputs a vibration damping signal obtained by multiplying the output value by a gain K to the actuator. A helicopter having a controller.

(2) The helicopter according to the above (1), further including interval maintaining means for fixing the interval between the aircraft body and the cabin in the machine axis direction substantially constant.

(3) The helicopter according to (1) or (2), wherein the actuator is a hydraulic actuator, and the hydraulic actuator and the spring are arranged in series to support the cabin.

(4) The helicopter according to (2), wherein the actuator is an electromagnetic actuator, and the electromagnetic actuator and a spring are arranged in parallel on the cabin support to support the cabin.

(5) The helicopter according to (1), (2), (3) or (4), wherein a damper is provided in the cabin support in parallel with the actuator to support the cabin.

(6) The helicopter according to (5), wherein the damper is a variable damper provided with an electrode in its cylinder and filled with an electrorheological fluid.

(7) A cabin weight detector, a co-oscillation frequency calculator for obtaining a spring resonance frequency from an output from the detector, a comparator for comparing the spring resonance frequency with the rotation speed of the main rotor, and a comparison result. And a damper controller for inputting the obtained variable attenuation adjustment signal to the variable damper.

(8) The helicopter according to (7), further including a main rotor rotation speed detector, and inputting the rotation speed obtained from the detector to the comparator.

(9) The helicopter according to (5), wherein the cabin is modularized and a modularized cabin can be mounted according to the purpose of flight.

In a helicopter, a rotor is rotated by an engine, and the aircraft is lifted up into the air by its lift to fly. In the helicopter according to the present invention, the cabin on which the passenger or the crew member rides is structurally separated from the body of the body having the engine or the rotor that is the vibration source. Then, the cabin is installed on the cabin support section of the body of the machine via both the spring and the actuator.

The purpose of separating the cabin and the fuselage main body is to structurally insulate vibration transmission from the fuselage main body to the cabin. Since the cabin needs to be supported by the main body, the cabin is supported by interposing an actuator and a spring between the cabin and the main body. This spring mainly generates a high frequency vibration (frequency =
N × (1 / rev) is passively absorbed to suppress propagation to the cabin. Similarly, the vibration by the rotor blade (frequency = 1 / rev) and the low-frequency resonance generated by the spring [frequency = (1 / 2π (k / m) ^1/2 , where k
Is the spring constant, m is the cabin weight.
It reduces the propagation of these vibrations to the cabin.

In order to perform this active vibration suppression, in the present invention, a vibration state is detected as acceleration or displacement from a vibration state quantity sensor in the cabin, and this value is input to a vibration suppression controller, and a gain K
By calculating the product of this value and a vibration suppression signal, and inputting the signal to the actuator, uncomfortable vibration of the cabin due to low-frequency resonance vibration is reduced.

When a hydraulic actuator is employed in the present invention, a lightweight, compact and powerful actuator can be obtained simply by using the conventional hydraulic system around the engine as it is. By utilizing the strong driving force of the normal hydraulic system, a sufficient force can be obtained even when the entire weight of the cabin is loaded on the hydraulic actuator. High frequency vibration and low frequency vibration can be reduced in a complex manner while supporting the entire weight.

Also, when the electromagnetic actuator is adopted in the present invention,
By providing a spring in parallel with the electromagnetic actuator, the spring can support the entire weight of the cabin and simultaneously absorb high-frequency vibrations. As a result, the electromagnetic actuator operates to eliminate only low-frequency resonance without supporting the cabin weight. Although an electromagnetic actuator originally has a quick response, it has a relatively small power, but if it is not necessary to support the cabin weight as described above, the advantage of the quick response can be effectively utilized.

As the spring, a coil spring, an air spring, or the like can be used according to its characteristics.

In the present invention, a damper can be provided in parallel with the actuator to support the cabin. When the cabin is supported by the spring and the actuator, if a soft spring is used so that high-frequency vibrations can be absorbed as much as possible, vibrations corresponding to the excitation force due to the rotation of the main rotor exist near the resonance frequency of the spring. Therefore, if the resonance peak (amplitude) of the spring is large, the amplitude is increased by this exciting force, and control by the actuator may become difficult. Therefore, by providing a damper, the resonance peak can be suppressed to a controllable degree. Even if the actuator stops operating due to a failure due to the provision of the damper, a certain amount of vibration can be suppressed by absorbing the damper.

It goes without saying that a normal damper having a constant damping force can be adopted as the damper. Alternatively, a variable damper capable of arbitrarily changing the damping force by providing an electrode in the cylinder of the damper, filling the electrorheological fluid and applying a voltage, is further adopted for the following reason. It is effective. That is, when the resonance frequency [fn = (1 / 2π) (k / m) ^1/2 ] of the spring and the frequency (1 / rev) of the vibration of the main rotor are close to each other, if the damper is provided, the lower frequency side becomes lower. The resonance peak certainly becomes gentle. However, at the same time, the gradient of the frequency-response curve itself becomes gentle, so that the absolute value of the response near the high-frequency harmonic component (N / rev) accompanying the rotation of the rotor blade becomes high, and the high-frequency vibration is reduced. The effect is somewhat reduced. Therefore, when the resonance frequency fn of the spring is not close to the frequency (1 / rev) of the main rotor, it is preferable to reduce the damping rate of the damper to some extent in order to reduce high-frequency vibration. As the helicopter changes the cabin weight m depending on the number of passengers and the weight of the luggage, measure the cabin weight at least before the flight, compare the resonance frequency fn of the spring with the frequency of the main rotor vibration (1 / rev) and compare If so, the voltage is adjusted so that the damping force of the variable damper is increased, and if the distance is large, the damping force of the variable damper is reduced. This makes it possible to reduce both low-frequency vibration and high-frequency vibration in a well-balanced manner.

In order to automate the adjustment of the above-mentioned variable damper,
The helicopter itself has a cabin weighing scale, and the output of the cabin weighing scale is input to a control device, and the resonance frequency fn of the spring is
And the frequency of the main rotor vibration (1 / rev) are compared and determined in the same manner as described above, and the result can be input as the voltage of the variable damper. By automating the adjustment of the variable damper in this way, both low-frequency vibration and high-frequency vibration can be automatically reduced with good balance.

In general, the rotation speed of the main rotor of a helicopter is generally constant, and it is possible to handle the rotation as it is input to the memory as a constant. However, FADEC (Full Auth
ority Digital Electronic Control (Digital Electronic Engine Control) to make the rotation speed of the main rotor variable, and to take off and land adjacent to a house, reduce the rotation speed to reduce the vibration noise to the surroundings, There is a helicopter that can increase the rotation speed and fly at high speed when cruising away from a house. In such a helicopter, a rotational speed detector of the main rotor is provided, and the frequency (1 / rev) of the main rotor vibration obtained as a result is compared with the resonance frequency fn of the spring obtained by the above method. ,
The damping force of the variable damper can be increased or decreased in the same manner as described above. In this manner, both the low-frequency vibration and the high-frequency vibration can be automatically reduced with good balance.

In addition, a stopper is provided between the cabin support portion or the body of the vehicle and the cabin so that the two do not spread beyond a certain distance, so that even if a large displacement other than vibration or an excessive load is applied, An excessive load is not applied to the actuator and the spring.

The helicopter vibration is the largest in the vertical direction,
Next, although the left-right direction is large, there is little in the front-back direction, that is, the machine axis direction. Therefore, the actuator and the spring
It is better to arrange the largest number of actuators so that the axes of the actuators are oriented in the vertical direction, and then to arrange several actuators in the horizontal direction, but they are often unnecessary in the front-rear direction. Therefore, by providing interval maintaining means for fixing the interval in the machine axis direction between the aircraft body and the cabin substantially constant, while suppressing the transmission of vibration to the cabin, and so that the cabin does not turn forward in front. , Can increase safety.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1a is a perspective view of a helicopter according to a first embodiment of the present invention, and FIG. 1b is a block diagram of a control system including a computer according to the present invention.

2a is a front view of a rod that can be used in the practice of the present invention, 2b is a side view of a hybrid actuator,
FIG. 2c is a schematic view showing a stopper for suppressing the movement of the cabin in the front-rear direction.

FIG. 3 is a flowchart of control of the hybrid actuator according to the first embodiment of the present invention.

FIG. 4 is a frequency-response characteristic diagram illustrating the effect of the present invention.

FIG. 5 is a side view of an actuator and a spring of a helicopter according to a second embodiment of the present invention.

FIG. 6 is a schematic side view of a helicopter according to a third embodiment of the present invention.

FIG. 7 is a graph illustrating the frequency of the effect of the helicopter of FIG.
It is a response characteristic diagram.

FIG. 8 is a schematic side view of a helicopter according to a fourth embodiment of the present invention.

FIG. 9 is a schematic sectional view of a variable damper used in the helicopter of FIG.

FIG. 10 is a frequency-response diagram illustrating the effect of the fourth embodiment.

FIG. 11 is a block diagram for explaining damper control of a helicopter according to the fifth embodiment of the present invention.

FIG. 12 is a block diagram for explaining damper control of a helicopter according to the sixth embodiment of the present invention.

FIG. 13 is a schematic perspective view of a helicopter according to a seventh embodiment of the present invention.

14a and 14b are enlarged side and front views, respectively, of the vicinity of the joint of the seventh embodiment.

 FIG. 15 is an explanatory diagram of cabin replacement according to the seventh embodiment.

FIG. 16 is a schematic side view of the cabin connecting portion of the seventh embodiment.

FIG. 17 is a schematic perspective view of a helicopter according to an eighth embodiment of the present invention.

18a, 18b and 18c show a helicopter according to another embodiment of the present invention, wherein FIG. 18a is a suspension type, FIG.
18c is a schematic side view of an internal helicopter.

19a and 19b show a conventional helicopter vibration reduction device.

BEST MODE FOR CARRYING OUT THE INVENTION FIGS. 1 to 4 are explanatory views of a helicopter according to a first embodiment of the present invention.

In FIG. 1, a helicopter includes a cabin 1 and a fuselage body 2.
And are structurally separated into The main body 2 is provided with a main rotor 21 that is rotated by an engine (not shown). The main rotor 21 is provided with four rotor blades (not shown), and by these rotations, a lift force for floating the helicopter is obtained. A tail rotor (not shown) is provided at the tail of the body 2 and the tail rotor is also driven by the engine. A cabin support 2 ′ on which the cabin 1 is placed is provided at the front of the body 2. This cabin support 2 '
Two beams (not shown) are protruded in parallel from the center of the body 2 and two beams are vertically provided on the beams to form a frame.

On such a frame of the cabin support 2 ', a hybrid actuator 3 in which a coil spring 6 and a hydraulic actuator 7 are combined in series as shown in FIG. 2b is mounted via a thin plate. At both ends of the hybrid actuator 3, there are mounting portions 8,9. The mounting portion 8 on the side of the coil spring 6 includes the hydraulic actuator 8 together with the coil spring 6.
Is supported by the cylinder shaft 13. These mounting parts 8,9
Is screwed to the body 2 and the other is screwed to the cabin 1 to support the cabin 1 on the body 2. The hydraulic actuator 7 is small but powerful.
The entire load of the cabin 1 can be borne. The hydraulic actuator 7 is driven and controlled by a servo valve 14.

Since the cabin 1 and the body 2 are structurally separated, vibration and noise can be cut off. And
High frequency vibration (frequency = N / rev) is passively absorbed by the coil spring 6. Further, the low frequency resonance that may occur in the coil spring due to the exciting force accompanying the rotation of the main rotor is actively reduced by the hydraulic actuator 7.

As shown in FIG. 2B, large displacements other than normal vibrations and excessive loads are received by stoppers 12 provided between the cabin 1 and the body 2 so that they are not applied to the hybrid actuator 3. Has become.

In this embodiment, four hybrid actuators 3 are provided vertically for reducing vertical vibration, and two hybrid actuators are provided horizontally for reducing horizontal vibration, and the cabin 1 is supported. Thereby, the vertical and horizontal vibrations of the cabin 1 are controlled. Since the vibration level is originally small in the front-rear direction, the vibration level is not particularly suppressed. As shown in FIG. 2c, the front-rear distance between the cabin 1 and the body 2 is substantially constant by the rod 11. The rod 11 is of a universal joint type that does not restrict movement other than in the front-rear direction.

An instruction system such as an electric wiring of a control device (not shown) of the cabin 1 is attached to the rod 11 or supported by the body 2 by a mechanism similar to the rod 11. Thereby, the electric wiring and the like can be prevented from being affected by the relative vibration between the cabin 1 and the body 2.

The cabin 1 includes an acceleration sensor 4 as a vibration state quantity sensor in addition to a steering device and a seat for an occupant. For the control of the hydraulic actuator 7, digital control is optimally performed by the control computer 5.

 Hereinafter, the optimal control will be described in detail.

The spring constant k of the coil spring 6 is set to a small value so as to absorb the vibration at the frequency N / rev of the high frequency vibration of the helicopter. When the spring constant k is set to a small value in this manner, the resonance frequency [(1 / 2π) (k
/ m) ^1/2 ] is very close to the frequency 1 / rev of the low frequency vibration of the helicopter. If high-frequency vibrations are reduced in current helicopters, the remaining low-frequency vibrations can cause discomfort. Furthermore, if the coil resonates with the coil spring 6, the fluctuation becomes considerably large, and the vibration becomes more unpleasant than the original high-frequency vibration.

Therefore, in order to reduce the low frequency vibration (1 / rev), the hydraulic actuator is actively driven. The control for this will be described with reference to FIGS. The vibration acceleration in the cabin 1 is detected by the acceleration sensor 4. The thus obtained acceleration is converted into a digital quantity by an A / D converter 5a in the control computer 5, and further converted into a state quantity in accordance with the calculation inside the computer (5b). This state quantity is multiplied by a predetermined gain K (5
c) The conversion from internal variables to physical quantities (5d) and analog quantities (5e) is performed again. Finally, a command signal is input to the hydraulic actuator portion of the hybrid actuator 3 that controls vibration.

Here, the gain K is, for example, a known optimal control theory LQG (L
inear Quadratic Method). For example, the equation of state: = AX + BU The gain K is determined in advance by the Hamilton equation or, in some cases, the Riccati equation so as to minimize the evaluation function J according to the following two equations.

FIG. 4 shows an example of a quantitative effect obtained by performing such control. High frequency vibration of about 20 Hz has already been absorbed by the coil spring 6. However, the rotation speed of the helicopter blade is
When the hydraulic actuator 3 was not used, the resonance peak of the coil spring 6 due to the low frequency vibration was about 0.5 G as shown by the dotted line. On the other hand, in the present embodiment using the controlled hydraulic actuator 3, the vibration acceleration was reduced to about 0.1 G as shown by the dashed line c. In FIG. 4, a solid line b shows a case where the hydraulic actuator 3 is not used but a damper is used.
Shows a case where both a hydraulic actuator and a damper are used.

When flying a helicopter equipped with such a vibration control device, the weight of the cabin 1 is detected based on the sinking amount of the cabin 1 by a displacement sensor 10 as a cabin weight detector before the flight, and the height of the cabin 1 is increased. The hydraulic actuator 7 is adjusted in advance so that the position of the hydraulic actuator 7 matches the position of the stopper 12. Since the amplitude of both the high-frequency vibration (frequency = N / rev) of the helicopter and the movement of the hydraulic actuator 7 at the low frequency is small, it is sufficient that the distance between the stoppers 12 is about several mm. As a result, even if there is a large displacement or a static load is applied, the load exceeding a certain range is
Since the stopper 12 receives, there is no problem with the strength of the aircraft,
Flight safety is not compromised. In addition, since the coil spring 6 suppresses high-frequency vibration and the hydraulic actuator 7 controls only low-frequency vibration, the power for performing active control is small, and the control system can be simplified and effective. . Further, the problem of vibration isolation of the conventional main gear box is solved.

In this way, vibration is reduced from low frequency to high frequency, and safe maneuverability is ensured by a maneuvering device that is not affected by relative vibration between the cabin 1 and the body 2.

Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, instead of a hybrid actuator in which a coil spring and a hydraulic actuator are provided in series, an air spring 16 and an electromagnetic actuator 17 are provided in parallel, and the cabin 1 is supported on the body body 2.

In this case, the air spring 16 supports the entire weight of the cabin 1 and absorbs high-frequency vibrations. Then, the electromagnetic actuator 17 is activated to lower the resonance peak of the low frequency. Since the cabin weight can be supported by the air spring 16, the capability of the electromagnetic actuator 17 may be relatively small. Therefore, a sufficiently small and lightweight electromagnetic actuator 17 can be used as a component of the helicopter. Further, by utilizing the quick response of the electromagnetic actuator 17, the vibration of the cabin 1 can be more effectively reduced. In addition, since it is a parallel type, not only the air spring 16 but also the electromagnetic actuator 17 itself must have a function of not transmitting high-frequency vibration. However, the fast-acting electromagnetic actuator 17 drives the actuator 17 only at the peak of low-frequency vibration, and
F can be in a non-operating state in which there is no actuator function and no vibration is transmitted. By using the electromagnetic actuator having good responsiveness, it becomes possible to absorb the high frequency vibration only by the air spring 16 while suppressing the resonance peak of the low frequency vibration by the electromagnetic actuator 17.

In the above example, since the control becomes somewhat complicated, the electromagnetic actuator 17 is also provided with a spring for absorbing high-frequency vibration in series to form a hybrid actuator, and an air spring 16 for supporting the load of the cabin 1 is provided in parallel with the hybrid actuator. Is more preferable. Further, in the above example, only the spring and the actuator have been described, but it goes without saying that the other configuration and operation are the same as in the first embodiment.

Next, a third embodiment for supporting the cabin 1 using a damper in addition to the above-described spring and actuator will be described with reference to FIG.

FIG. 6 shows the spring 16 and the actuator of the second embodiment of FIG.
In addition to 17, dampers 18 are provided in parallel. As a result, the resonance peak of the low frequency caused by the spring 16 to be controlled by the actuator 17 becomes lower, so that the cabin 1
Is more effectively reduced. And, by any chance,
Even when a failure of the actuator 17 occurs and the resonance peak of the low frequency is not suppressed, it is possible to prevent an excessive response by the damper 18, so that the helicopter can be more comfortable to ride.

In the third embodiment shown in FIG. 6, an example is described in which the damper 18 is applied to a configuration in which the spring 16 and the actuator 17 are used in parallel for convenience of explanation. Dampers 18 in parallel with those of FIGS.
The same effect can be obtained by providing. Further, when the damper 18 and the actuator 17 are installed in parallel as in the above example, the damping effect on the movement of the entire cabin 1 is greater. Therefore, if it is physically parallel, it is not necessary to be at a specific position.However, it is possible to mount the damper 18 adjacent to the mounting part of the actuator 17 in the sense of arranging the equipment in the same place considering the ease of maintenance of the body. desirable.

FIG. 6 is a schematic diagram showing only the positional relationship of the damper 18 with respect to the actuator 17 and the spring 16, and the illustration is omitted except for this point. Needless to say, the same maintenance and the same functions and effects as those of the first and second embodiments are provided.

Next, a helicopter in which the damping capacity of the damper 18 of the third embodiment is variable will be described as a fourth embodiment of the present invention, focusing on the differences from the above embodiments with reference to FIGS. .

FIG. 7 is a frequency-response characteristic diagram, in which the vertical axis shows the response to vibration (log scale), and the horizontal axis shows the frequency of vibration. Line 21 in the figure shows a case where no damper is used,
Line 22 shows the characteristics when a damper is used. As can be seen from the figure, when the damper is used, in the low frequency vibration region near the resonance peak of the spring, the peak decreases from the point 211 to the point 221. However, the gradient of the entire response curve becomes gentle. Conversely, at about 20 Hz), the absolute value of the response becomes larger from point 214 to point 224 in the figure when the damper is used. This means that a considerable part of the spring 6,16
However, the use of the damper 18 enables the high frequency vibration (N / re
v) means increased response to cabin 1
It means that improvement is required to improve ride comfort.

As described in the third embodiment, the damper 18 includes the springs 6, 16
The main purpose is to reduce the resonance peak when the resonance occurs due to the low-frequency vibration (1 / rev) accompanying the rotation of the rotor. Therefore, in a situation where the resonance peak is relatively small, the damping capacity of the damper 18 is reduced. It can be small. Therefore,
As shown in FIG. 8, there is an advantage that the damper 18 of the third embodiment is changed to a variable damper 19.

Specifically, as shown in FIG.
The electrode 27 is provided inside, and the electrorheological gas is
The one filled with 28 is referred to as a variable damper 19. In the drawings, the variable damper 19 has a piston portion 26, and the holes of the cylinder 25 and the piston 26 are fixed to the body 2 and the cabin 1, respectively. A seal 29 and an orifice 30 are provided at a portion where the piston 26 and the cylinder 25 are in contact with each other. Here, the electrorheological fluid is a fluid whose technical progress is still remarkable at present, but is generally manufactured by dispersing and mixing particles suitable for the purpose, such as starch, cellulose, and silica gel, among others. It shows a characteristic that the flow resistance (attenuation) increases as the applied voltage increases.

Next, how to use the variable damper 19 will be described.

As described above, the damper changes the helicopter rotor speed (1 / rev) so that the resonance frequency of the spring 16 [fn = (1 / 2π) (k /
m) ^1/2 ], the vibration of the spring 16 is suppressed from becoming extremely large, and the purpose is to suppress the vibration to such an extent that the actuator 17 can control the vibration. Therefore, the resonance frequency fn of the spring 16 changes with the change in the weight (m) of the cabin 1 due to the change in the occupant or the load, or the rotor speed (1 / rev) itself changes, thereby changing the rotor speed (1).
/ rev) and the resonance frequency (fn) of the spring, there is no need for damping. Therefore, the voltage of the variable damper 19 is reduced, the damping rate is reduced, and the response at high frequencies is also reduced. Can be done. As a result, a quiet cabin 1 with low vibration can be realized for both high frequency and low frequency.

Specifically, after the load and the passengers board, the displacement sensor 10 in FIGS. 1 and 2 detects the weight of the cabin 1 and adjusts the position of the actuator 7 to match the position of the stopper 12. At this time, the resonance frequency fn of the spring 6
(1 / 2π) (k / m) ^1/2 ] is also calculated and compared with a known rotation speed 1 / rev of the helicopter blade. If these values are close, the voltage of the variable damper 19 is turned on. ,
Take action such as turning off or weakening the voltage if it is far away.

The response when the cabin weight changes will be described with reference to the frequency-response characteristic diagram of FIG.

In the helicopter according to the third embodiment using the damper 18 having a constant damping rate, if the response of the cabin 1 is relatively light as shown by the line 22 when the cabin 1 is relatively light, the response curve becomes linear even if the weight increases. As shown in Fig. 24, it only shifts to the left of the figure. That is, in the helicopter of the third embodiment, the response at the low frequency (approximately 5 Hz) corresponding to the exciting force of the rotor blade is a response indicated by points 223 and 463, respectively, while the high frequency of approximately 20 Hz In vibration (N / rev), point 22
4. High responsiveness as shown by point 244.

On the other hand, in the helicopter of the fourth embodiment using the variable damping damper 19, the cabin 1 is relatively light, and the resonance frequency (fn) of the spring (point 221) and the vibration force of the rotor blade are approximately equal. When the low frequency of 5Hz is close,
The response is as shown by line 22 by the damper 19. However, when the weight increases and the resonance frequency (fn) moves away to the point 231, the response response corresponding to the low frequency of the rotor blade (about 5 Hz) decreases to the point 233, so that particularly strong damping is required. Instead, by weakening the variable damper 19, the response is as shown by the line 23. As a result, the response of the rotor blade in the high-frequency vibration 24 decreases from the point 244 to the point 234 as compared with the case where the damping is performed.

Similarly, the case where the rotation speed of the rotor blade is variable will be described with reference to the frequency-response characteristic diagram of FIG. When the rotation speed of the rotor blade is low, for example, 5 Hz, the high frequency vibration by the four blades is 20 Hz,
Since the rotation frequency of the rotor blade is close to the resonance frequency of the spring (frequency at point 221), damping is required to avoid resonance, and as a result, the response curve is as indicated by reference numeral 22.

Next, when the rotation speed of the rotor blade of the helicopter is increased to 7 Hz, the rotation speed is considerably higher than the resonance frequency of the spring (the frequency at the point 221), so that the influence of the resonance is reduced. As a result, the necessity of damping is reduced, and if the applied voltage of the variable damper 19 is reduced or set to zero,
The response is as shown by curve 21. The peak at the resonance frequency increases as indicated by the reference numeral 211, but decreases near the rotation speed (7 Hz) of the rotor blade as indicated by a point 212, and the high-frequency vibration, which is a higher harmonic, increases to about 28 Hz. It can be seen that the response of the spring decreases.

In this way, by using the variable damper 19 in combination, the cabin 1 is supplied to the cabin 1 in both low-frequency vibration and high-frequency vibration even when the operating conditions change, such as the weight of the cabin and the rotation speed of the rotor blade. Vibration can be reduced.

Next, a helicopter in which the control of the variable attenuation damper 19 is automated will be described with reference to FIGS.

FIG. 11 shows the fifth case where the rotation speed of the rotor blade is constant.
In the embodiment, the rotation speed is stored in a memory 37 in the control computer 5. FIG. 12 shows a sixth embodiment applied to a helicopter in which the rotation speed of a rotor blade can be arbitrarily changed by FADEC or the like. As the rotation speed changes,
A rotation speed detector 39 is provided instead of the eleven memories 37.
In any case, after outputting the rotation speed of the rotor blade to the comparator 36, the same processing is performed.

The cabin 1 is mounted on the body 2 via a spring 16, an actuator 17 and a variable damper 19.
The rear portions are supported by rods 11, respectively. A displacement sensor 10 is provided at a lower portion of the cabin 1 to detect a load or a cabin weight m with a passenger on board.
The cabin weight detection signal 33 is input to a resonance frequency calculator 35 in the control computer 5, and calculates the resonance frequency fn of the spring 16 by the above-described calculation formula. The determined resonance frequency fn is input to the comparator 36, and the rotation speed (1 / re of the rotor blade) input from the memory 37 or the rotation speed detector 39.
v) is compared with The result of the comparison is input to the damper controller 38, and when the two values are close to each other, the damping efficiency of the damper 19 is increased, and when the difference between them is large, the variable damping adjustment is performed so as to decrease the damping rate of the damper 19. Variable attenuation damper for signal 34
Output to 19.

Since the weight of the cabin 1 usually does not change after the helicopter starts flying, in the fifth embodiment shown in FIG. 11, the setting of the above-mentioned attenuation rate is completed before the flight starts. On the other hand, in the sixth embodiment shown in FIG. 12, the rotation speed of the rotor blade may need to be changed during flight depending on the flight condition, and the attenuation rate is corrected in real time even during flight.

If the number of rotations of the rotor blade can be changed during flight as in the sixth embodiment, a relatively quiet flight is performed by reducing the number of rotations where there are many houses, and the number of rotations is small where there are few houses. As a result, a high-speed flight is possible, so that a helicopter that can maintain an environment with relatively little vibration and noise not only for the occupants in the cabin 1 but also for people outside the helicopter can be realized.

Further, in the present invention, since the cabin 1 is structurally separated from the body 2 of the vehicle, as shown in the seventh embodiment in FIG. 13, the passenger cabin 1a, the luggage cabin 1b, and the emergency medical activity cabin 1c. As described above, the cabin 1 having the same shape can be used as a module in which the interior of the cabin is set in advance for each application. In this case, as shown in FIG. 14 and FIG.
Provided is a small opening 43 convenient for the work of connecting to (the state where the small door attached to this opening 43 is opened in FIG. 15),
The mounting portion 8 is a simple one such as a pin or a bolt, which is easy to replace.

Also, the connecting portion of the steering device to the body 2 side is a bolt or pin connection at a specific portion as much as possible. In particular,
As shown in the partially enlarged view of FIG. 16, the steering linkage 50 is basically attached to the machine body 2 side, and the hinge point 49 is provided on the cabin 1 side to the steering stick 40 that finally comes close to the pilot rod. Is done. Therefore, when the cabin 1 is separated, the cabin 1 is attached and detached at the hinge point 49 on the cabin side. The electric cable 48 is connected between the cabin 1 and the body 2
A connector 47 is provided between them. The hydraulic system is basically provided only in the body 2 of the machine.

The modularized cabin 1 is replaced by lifting the hook fitting 46 of the cabin 1 with the crane 45. Fig. 15
When the rail-shaped stopper 44 is provided on the cabin support 2 'of the body 2 as described above, the cabin 1 can be easily replaced by sliding the cabin 1 from the front. In the above example, the cabins 1 have the same shape. However, as long as the weight and the center of gravity of the cabin 1 and the position and size of the mounting portion 8 are substantially the same, there is no particular problem even if they are not the same shape.

As described above, if the cabin 1 can be modularized,
In addition to the above-mentioned vibration reduction effect, a special-purpose cabin is used, making it an efficient and easy-to-use helicopter. In addition, the work of changing the cabin equipment for each application is greatly simplified and speeded up, and many more different applications are used. Therefore, there is a merit that utilization efficiency of one helicopter is improved.

In each of the above-described embodiments, particularly, the configuration of each object has been mainly described, and therefore, for parts that are not directly related to this description, illustration and description of the configuration, operation, and effects may be omitted. Each of the above embodiments also has the same configuration as the helicopter of the first embodiment or the second embodiment, and it goes without saying that the same operation and effect can be obtained.

Further, in each of the embodiments, the arrangement of the spring and the actuator is described as an example of only one of the series and the parallel for the sake of space. However, any of them can be used either in series or in parallel. .

Further, various arrangements of the hybrid actuator 3 in FIG. 1 may be considered depending on the scale of the airframe main body 2, the weight of the cabin 1, the shape of the airframe main body 2, and the like. When the helicopter is small and the cabin 1 is light, FIG. As shown in FIG. 7, even with a small number of hybrid actuators 3, a good vibration reduction effect can be obtained. In the case of the helicopter shown in FIG. 17, since the cabin 1 is lightweight and compact, the hybrid actuator 3 can be used instead of the rod 11.

In addition, there are various cases in which the cabin 1 and the fuselage main body 2 are separated depending on the form of the fuselage, and various types are considered as shown in FIG. You can choose.

FIG. 18a shows a type in which the cabin 1 is suspended from the fuselage body 2 via the hybrid actuator 3, and a strong stopper (12 in FIG. 2b) is provided near the hybrid actuator 3, although not shown. Cabin 1 when the hybrid actuator 3 is damaged
Is safely suspended. Further, a rod 11 is provided so that the cabin 1 does not move in the front-rear direction.

FIG. 18b is also of the suspension type, but the cabin 1 is not suspended directly on the body 2 of the vehicle, but is suspended via the hybrid actuator 3 provided on the legs 41. In this case, an L-shaped cabin support portion 42 is provided further below the cabin 1 of the leg 41 so that the cabin 1 will not drop even if the hybrid actuator 3 is broken. .

FIG. 18C shows a case in which a cylindrical cavity is provided in the front part of the body 2 and the cabin 1 is supported in the cavity from above, below, left and right by a hybrid actuator (not shown). Together with a rod (not shown) provided at a deep portion of the body of the body 2, the helicopter is more secure.

As described above, the embodiment of the present invention functions and produces effects as follows.

In the above-mentioned helicopter of the present invention, by separating the cabin 1 from the body 2, vibrations including the vibration of the helicopter at the vibration frequency N / rev in the cabin 1 are greatly reduced, and at the same time, the noise transmitted through the body And a comfortable ride is realized. That is, the cabin 1 is supported by the hybrid actuator 3 in which the coil spring 6 and the hydraulic actuator 7 are combined, or by the air spring 13 and the electromagnetic actuator 14, and the high frequency is controlled by the spring and the low frequency is controlled by the actuator. The effect of vibration reduction larger than in the case can be easily obtained without using a complicated system as in the case of controlling only by the actuator. Further, by providing the stopper 12 between the cabin 1 and the body 2, static movement is suppressed, and the body can easily withstand a large displacement and an excessive load. Note that the division of the cabin 1 by the stopper 12 and other safety devices has no effect on flight safety. Further, since high-frequency vibration is suppressed by a spring and the actuator controls only low-frequency vibration, the power for driving the actuator may be small, and the control system is simplified. In addition, by using digital optimal control for controlling the actuator, a large vibration reduction effect can always be maintained even when there are changes in the flight conditions, the weight of the cabin 1, and the like. As described above, the helicopter according to the present invention can cut off vibration and noise that a passenger in the cabin feels uncomfortable, and can realize a comfortable ride.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 60-124384 (JP, U) JP 2-9988 (JP, B2) JP-B 55-47658 (JP, B2) JP 5-205 4472 (JP, Y2) US Patent 5044455 (US, A) US Patent 3,857,534 (US, A) EP 530075 (EP, A1) EP 511055 (EP, A2) EP 382171 (EP, B1) (58) Search Field (Int.Cl. ⁶ , DB name) B64C 27/04 B62D 27/04 F16F 9/50

Claims (9)

(57) [Claims] 1. A main rotor having a plurality of blades, an engine for driving the main rotor, an airframe main body having the engine therein and having a cabin support, a spring and an actuator provided alongside the cabin support, A cabin supported by the cabin support via the spring and the actuator; and a cabin support in parallel with the actuator so as to limit a distance between the cabin support and the cabin due to vibration to within a certain range. A stopper provided between the body of the machine and the cabin; a vibration state quantity sensor provided in the cabin; a control for receiving an output of the sensor and inputting a vibration damping signal obtained by multiplying the gain by a gain K to the actuator; A helicopter comprising: a vibration controller. 2. The helicopter according to claim 1, further comprising a gap maintaining means for fixing the gap between the body and the cabin in the machine axis direction substantially constant. 3. The helicopter according to claim 2, wherein the actuator is a hydraulic actuator, and the hydraulic actuator and a spring are arranged in series to support the cabin. 4. The helicopter according to claim 2, wherein the actuator is an electromagnetic actuator, and the cabin is supported by disposing the electromagnetic actuator and a spring in parallel with the cabin support. 5. The helicopter according to claim 1, wherein a damper is provided in the cabin support portion so as to support the cabin in parallel with the actuator. 6. The helicopter according to claim 5, wherein said damper is a variable damper, an electrode is provided in a cylinder thereof, and said cylinder is filled with an electro-rheological fluid. 7. A cabin weight detector, a resonance frequency calculator for obtaining a spring resonance frequency from an output from the detector, a comparator for comparing the spring resonance frequency with the rotation speed of the main rotor, and a result of the comparison. 7. The helicopter according to claim 6, further comprising: a damper controller that outputs a variable attenuation adjustment signal obtained from the variable damper to the variable damper. 8. The helicopter according to claim 7, further comprising a main rotor rotation speed detector, and outputting the rotation speed obtained from the detector to the comparator. 9. The helicopter according to claim 5, wherein the cabin is modularized and a modularized cabin can be mounted according to the purpose of flight.