JP5689447B2 - Electric actuator - Google Patents

Description

The present invention relates to a working fluid supply device capable of supplying a working fluid and an electric actuator using the working fluid supply device.

  Conventionally, as an electric actuator using a working fluid supply device capable of supplying a working fluid, one described in Patent Document 1 is known. The electric actuator includes an electric motor, a pump that outputs oil according to the rotation of the electric motor, a cylinder that receives oil output by the pump, and a control unit that controls the rotation of the electric motor according to the movement of the cylinder, And a backup valve for circulating oil output from the pump to the cylinder. And when the pressure of the oil input into a cylinder becomes a pressure more than predetermined pressure, a backup valve prevents distribution of the oil outputted by the pump. According to this configuration, since the backup valve faces the load applied to the cylinder by preventing the oil output from the pump from flowing, it is not necessary for the pump to supply oil to the cylinder.

JP 2002-54604 A

  However, in the electric actuator described in Patent Document 1, when high pressure oil is supplied from a pump, it is necessary to drive the electric motor so that high torque can be output. That is, it is necessary to apply a large current to the electric motor that drives the pump. In this case, the amount of heat generated by the motor and the control means of the motor increases. When the temperature of the electric motor or the like rises due to this heat generation, there is a concern that the reliability of the electric actuator may be reduced, such as a problem in drive control of the electric actuator. To solve this problem, a sufficient heat radiation area is required, and the volume and weight of the electric actuator tend to increase. Further, since it is necessary to energize the electric motor with a large current, the power consumption of the electric actuator becomes large, which is a problem.

  In view of the above circumstances, an object of the present invention is to provide a working fluid supply device capable of supplying a working fluid having a low pressure and a high pressure, and an electric actuator capable of exerting a large force at a low current.

Means and effects for solving the problems

  The present invention relates to a working fluid supply device capable of supplying a working fluid and an electric actuator using the working fluid supply device. And the working fluid supply apparatus and electric actuator which concern on this invention have the following some features in order to achieve the said objective. That is, the working fluid supply apparatus and the electric actuator of the present invention are provided with the following features alone or in combination as appropriate.

  In order to achieve the above object, the first feature of the working fluid supply apparatus according to the present invention includes a variable speed electric motor, a variable displacement pump driven by the variable speed electric motor and capable of discharging the working fluid, and set An electric motor controller for controlling the variable speed electric motor so as to achieve a rotation speed; and the variable displacement pump so that a discharge volume of the variable displacement pump decreases as a discharge pressure of the variable displacement pump increases. And a pump control unit for controlling.

  According to this configuration, the discharge pressure of the variable displacement pump can be increased without excessively increasing the current flowing through the variable speed electric motor. Furthermore, the flow rate of the working fluid discharged from the variable displacement pump can be increased without excessively increasing the rotational speed of the variable speed electric motor.

  Further, a second feature of the working fluid supply apparatus according to the present invention is that, in the working fluid supply apparatus having the first feature, the pump controller is configured to increase the discharge pressure of the variable displacement pump. The variable displacement pump is controlled so that the discharge volume of the variable displacement pump is reduced proportionally.

  According to this configuration, the relationship between the discharge pressure and the discharge volume is not complicated, and the variable product pump can be easily controlled.

  Further, a third feature of the working fluid supply device according to the present invention is that, in the working fluid supply device having the first or second feature, the pump control unit is configured to control the working fluid discharged from the variable displacement pump. An operating member that moves when pressure acts to increase or decrease the discharge volume of the variable displacement pump; and an elastic member that biases the operating member against the pressure of the working fluid that acts on the operating member; Is.

  According to this configuration, the pump controller that controls the variable displacement pump can be realized with a simple configuration so that the discharge volume of the variable displacement pump decreases as the discharge pressure of the variable displacement pump increases.

  The fourth feature of the working fluid supply apparatus according to the present invention is that a variable speed motor, a variable displacement pump driven by the variable speed motor and capable of discharging working fluid, and a desired rotational speed are provided. When the discharge pressure of the motor controller for controlling the variable speed motor and the variable displacement pump is smaller than a predetermined pressure, the variable volume pump is configured so that the discharge volume of the variable displacement pump becomes the first discharge volume. And when the discharge pressure of the variable displacement pump reaches the predetermined pressure, the discharge volume of the variable displacement pump is set to a second discharge volume smaller than the first discharge volume. And a pump control unit that controls the variable displacement pump.

  According to this configuration, the variable displacement pump is controlled to have the second discharge volume, so that the discharge pressure of the variable displacement pump can be increased without excessively increasing the current flowing to the variable speed electric motor. . Furthermore, the flow rate of the working fluid discharged from the variable displacement pump is increased without excessively increasing the rotation speed of the variable speed motor by controlling the variable displacement pump so as to have the first discharge volume. be able to.

  The fifth feature of the working fluid supply apparatus according to the present invention is that, in the working fluid supply apparatus having the fourth feature, the pump controller is operated by the pressure of the working fluid discharged from the variable displacement pump. An operating member that moves to increase or decrease the discharge volume of the variable displacement pump, an elastic member that biases the operating member against the pressure of the working fluid acting on the operating member, and the variable A first switching position provided between the positive displacement pump and the actuating member and blocking a flow path communicating the variable positive displacement pump and the actuating member; and communicating the variable positive displacement pump and the actuating member. A switching valve switchable to the second switching position, and the switching valve is held at the first switching position when the discharge pressure of the variable displacement pump is smaller than the predetermined pressure, Said It is that the discharge pressure of the variable displacement pump is switched to the second switching position and reaches the predetermined pressure.

  According to this configuration, when the discharge pressure of the variable displacement pump is smaller than a predetermined pressure, the variable displacement pump is controlled so that the discharge volume of the variable displacement pump becomes the first discharge volume, When the discharge pressure of the variable displacement pump reaches the predetermined pressure, the pump control unit that controls the variable displacement pump has a simple configuration so that the discharge volume of the variable displacement pump becomes the second discharge volume. realizable.

  A sixth feature of the working fluid supply apparatus according to the present invention is that the variable speed motor, the variable displacement pump driven by the variable speed motor and capable of discharging the working fluid, and a desired rotational speed are provided. An electric motor control unit that controls the variable speed motor, and the variable displacement pump so that the discharge volume of the variable displacement pump becomes the first discharge volume until a predetermined time elapses after the rotation speed of the variable speed motor becomes stable. When a predetermined time elapses after the displacement pump is controlled and the rotation speed of the variable speed motor is stabilized, the discharge volume of the variable displacement pump becomes a second discharge volume smaller than the first discharge volume. And a pump controller for controlling the variable displacement pump.

  According to this configuration, the discharge pressure of the variable displacement pump can be increased without excessively increasing the current flowing through the variable speed motor after a predetermined time has elapsed since the rotation speed of the variable speed motor has stabilized. it can. Furthermore, before the predetermined time has elapsed since the rotation speed of the variable speed motor has stabilized, the flow rate of the working fluid discharged from the variable displacement pump is increased without excessively increasing the rotation speed of the variable speed motor. Can be made.

  The seventh feature of the working fluid supply apparatus according to the present invention is the working fluid supply apparatus having the sixth feature. In the working fluid supply apparatus, the pump controller is operated by the pressure of the working fluid discharged from the variable displacement pump. An operating member that moves to increase or decrease the discharge volume of the variable displacement pump, an elastic member that biases the operating member against the pressure of the working fluid acting on the operating member, and the variable A first switching position provided between the positive displacement pump and the actuating member and blocking a flow path communicating the variable positive displacement pump and the actuating member; and communicating the variable positive displacement pump and the actuating member. A switching valve switchable to the second switching position, and the switching valve is held at the first switching position until a predetermined time elapses after the rotational speed of the variable speed motor is stabilized. ,Previous Rotational speed of the variable speed motor is to switch to the second switch position and a predetermined time elapses after stable.

  According to this configuration, the variable displacement pump is controlled so that the discharge volume of the variable displacement pump becomes the first discharge volume until a predetermined time elapses after the rotation speed of the variable speed motor is stabilized, When a predetermined time elapses after the rotation speed of the variable speed motor is stabilized, a pump control unit that controls the variable displacement pump so that the discharge volume of the variable displacement pump becomes the second discharge volume is simplified. It can be realized by configuration.

  An eighth feature of the working fluid supply apparatus according to the present invention is the working fluid supply apparatus having the third feature, the fifth feature, or the seventh feature, wherein the pump control unit is the variable displacement pump. And a pressure adjusting unit that adjusts the pressure of the working fluid that acts on the operating member from the variable displacement pump.

  According to this configuration, the pressure acting on the operating member can be adjusted. Thereby, the freedom degree of design of the said operation member and the said elastic member in the pump control part which controls the discharge volume of the said variable displacement pump can be raised.

  The first feature of the electric actuator according to the present invention is that the working fluid output from the working fluid supply device having the combination of the first to eighth features or any one of the features and the variable displacement pump is provided. And an actuator that operates upon input.

  According to this configuration, since the working fluid supply device can supply a working fluid having a low current and a high pressure to the actuator, a large force can be exhibited with a low current. Furthermore, since the flow rate of the working fluid discharged from the variable displacement pump can be increased without excessively increasing the current flowing to the variable speed motor, a large flow rate of working fluid is supplied to the actuator at a low current. Thus, the actuator can be driven.

  Moreover, the 2nd characteristic in the electric actuator which concerns on this invention is using in order to drive the control surface of the wing of an aircraft in the electric actuator which has a 1st characteristic.

During the flight of the aircraft, a high load due to air resistance acts on the control surface provided on the wing of the aircraft (hereinafter, the high load acts on the control surface during the flight, and the actuator is positioned against the load. The held state is called a stalled state.) Therefore, in the stall state, the actuator that drives the control surface is required to generate a large force against a load due to air resistance. On the other hand, for example, in a state where the load acting on the control surface is small, such as a standby state before takeoff, it is desired to adjust the control surface position at a higher operating speed.
In this regard, according to this configuration, since a working fluid having a low current and a high pressure can be supplied to the actuator, it is possible to reduce the power consumption in the stall state and to suppress the heat generation of the variable speed electric motor. Furthermore, the operating speed can be increased when the load acting on the control surface is small.

It is a figure which shows the hydraulic circuit of the electric actuator which concerns on 1st Embodiment of this invention. It is a figure which shows the aircraft provided with the electric actuator shown in FIG. It is a figure which shows the relationship between the discharge pressure and discharge volume of the variable displacement pump shown in FIG. FIG. 2 is a schematic diagram showing a relationship between an axial force and an operating speed of the actuator and a relationship between an axial force and a motor current in the electric actuator shown in FIG. 1. It is a figure which shows the relationship between the discharge pressure of the variable displacement pump in a modification, and a discharge volume. It is a figure which shows the hydraulic circuit of the electric actuator which concerns on 2nd Embodiment of this invention. It is a figure which shows the hydraulic circuit of the electric actuator which concerns on 3rd Embodiment of this invention. It is a figure which shows the relationship between the discharge pressure and discharge volume of the variable displacement pump shown in FIG. It is a figure which shows the hydraulic circuit of the electric actuator which concerns on 4th Embodiment of this invention. It is a figure which shows the relationship between the discharge pressure and discharge volume of the variable displacement pump shown in FIG.

(First embodiment)
Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a hydraulic circuit of the electric actuator according to the first embodiment of the present invention.
In FIG. 1, an EHA (Electro Hydrostatic Actuator) 1 as an electric actuator is driven by a hydraulic pressure supply device 10 (working fluid supply device) according to an embodiment of the present invention and the pressure of oil supplied from the hydraulic pressure supply device 10. And a hydraulic cylinder 20 as a hydraulic actuator.

  The hydraulic pressure supply device 10 includes a servo motor 11 (variable speed electric motor) and a variable displacement pump 12 that can output oil (working fluid) to two paths (an oil path 41a and an oil path 42a) according to the rotation of the servo motor 11. A motor control device 13 (electric motor control unit) that controls the servo motor 11 to have a set rotational speed, a pump control device 14 (pump control unit) that controls the discharge volume of the variable displacement pump 12, It has.

  As the variable displacement pump 12, for example, a swash plate type axial piston pump can be used. In this case, the drive shaft of the servo motor 11 is connected to the cylinder block of the variable displacement pump 12.

  Further, the drain oil discharged from the variable displacement pump 12 can pass through the drive mechanism of the servo motor 11 and be discharged to the oil passage 40 to which the accumulator 30 is connected. Thereby, the drain oil of the variable displacement pump 12 can be discharged, and the servo motor 11 can be cooled, lubricated, and the like.

  The hydraulic cylinder 20 is a cylinder to which the oil output from the variable displacement pump 12 is input. The hydraulic cylinder 20 includes a cylinder body 21, a piston 22 disposed in the cylinder body 21, and a rod 23 that is integrally engaged with the piston 22. The cylinder body 21 and the piston 22 form an oil supply chamber 20a to which oil is supplied through an oil passage 41b and an oil supply chamber 20b to which oil is supplied through an oil passage 42b.

  A switching valve 50 is provided between the variable displacement pump 12 and the hydraulic cylinder 20. The switching valve 50 can be switched between the first switching position 50A and the second switching position 50B by, for example, an electromagnetic valve or a pilot pressure operation type mode valve. The first switching position 50A is a switching position that connects the oil passage 41a and the oil passage 41b and connects the oil passage 42a and the oil passage 42b. The second switching position 50B blocks the oil path 41a and the oil path 41b, blocks the oil path 42a and the oil path 42b, and connects the oil path 41b and the oil path 42b via the throttle path. This is a switching position for communication. For example, when a solenoid valve is used, the switching valve 50 is configured to be energized from an external control device (not shown), and is switched to the first switching position 50A in the energized state and is switched to the first in the non-energized state. 2 Switch to the switching position 50B.

  The servo motor 11 is provided with a sensor (not shown) for detecting the rotational position of the servo motor 11 and can calculate the rotational speed. For example, a resolver, a Hall effect element, a pulse generator, or the like is used as the sensor.

  The motor control device 13 is provided with a speed command generator (not shown) for setting the rotation speed of the servo motor 11. Then, the motor control device 13 supplies a predetermined current to the servo motor 11 based on the speed command signal and the speed information obtained from the position signal of the sensor provided in the servo motor 11. Feedback control is performed so that the rotation speed of the motor becomes a desired rotation speed.

  Further, the motor control device 13 includes means for detecting the position of the rod 23 (for example, a linear type actuating transformer is disposed on the hydraulic cylinder 20 and the rod 23, and the motor control device 13 is provided with an excitation section of the linear type differential transformer, Etc.), a speed command for the servo motor 11 is generated based on the position information, and a current corresponding to the difference between the speed command and the speed feedback is output to the servo motor 11 to generate a hydraulic pressure. The rotation of the servo motor 11 can be controlled according to the movement of the cylinder 20.

  The pump control device 14 includes an inclination angle adjusting cylinder 17, an oil passage 41 communicating with the oil passage 41 a and the oil passage 42 a, and the inclination angle adjusting cylinder 17, a check valve 181 provided in the oil passage 18 and a reverse valve. A stop valve 182. The oil passage 18 includes an oil passage 18a branched from the oil passage 41a, an oil passage 18b branched from the oil passage 42a, and an oil passage 18c that joins and communicates with the inclination angle adjusting cylinder 17.

  The check valve 181 is provided in the oil passage 18a, allows oil flow from the oil passage 41a to the inclination angle adjustment cylinder 17, and blocks oil flow from the inclination angle adjustment cylinder 17 to the oil passage 41a. The check valve 182 is provided in the oil passage 18b, allows oil to flow from the oil passage 42a to the inclination angle adjustment cylinder 17, and blocks oil flow from the inclination angle adjustment cylinder 17 to the oil passage 42a. .

  The tilt angle adjusting cylinder 17 includes a cylinder body 71, a piston 72 (operation member) disposed in the cylinder body 71, a rod 73 (operation member) integrally engaged with the piston 72, and the piston 72. And a spring 74 (elastic member) to be energized. The cylinder body 71 and the piston 72 form a first oil supply chamber 17a to which oil is supplied via the oil passage 18c, and a second oil supply chamber 17b capable of discharging oil to the oil passage 43. . The piston 72 is formed with a throttle passage 72a that communicates the first oil supply chamber 17a and the second oil supply chamber 17b.

  The rod 73 can advance and retract from the cylinder body 71 as the piston 72 reciprocates within the cylinder body 71. The rod 73 is connected to the swash plate of the variable displacement pump 12. When the rod 73 moves from the cylinder main body 71 in the direction of advancement (hereinafter referred to as the advancement direction), the inclination angle of the swash plate decreases, and the direction of the rod 73 retracting into the cylinder main body 71 (hereinafter referred to as the retraction direction). The inclination angle of the swash plate is increased when the movement is performed. That is, when the rod 73 moves in the advancing direction, the discharge volume (hereinafter simply referred to as the discharge volume), which is the volume (capacity) of oil discharged when the variable displacement pump 12 is rotated once by the servo motor 11 decreases. However, when the rod 73 moves in the retracting direction, the discharge volume increases.

  The spring 74 is disposed in the second oil supply chamber 17b and biases the piston 72 in a direction (retracting direction) in which the first oil supply chamber 17a is narrowed. When no hydraulic pressure is generated in the first oil supply chamber 17a, the piston 72 is biased by the spring 74 toward the retracting direction, and comes into contact with the inner end surface of the cylinder body 71 to move in the retracting direction. The movement of is restricted. Further, when the piston 72 comes into contact with a convex seat formed on the inner peripheral wall of the cylinder body 71 at a position moved by a predetermined amount in the advance direction, the movement of the piston 72 in the advance direction is restricted. It is comprised so that.

  Further, the EHA 1 includes an accumulator 30 that supplies oil through the oil passage 31 when the flow rate of the oil flowing through the oil passage 41a, the oil passage 42a, the oil passage 41b, and the oil passage 42b is insufficient. . The accumulator 30 and the servo motor 11 communicate with each other through an oil passage 40. An oil passage 43 communicates from the oil passage 40 to the second oil supply chamber 17 b of the tilt angle adjusting cylinder 17.

  The EHA 1 includes an oil passage 41a, an oil passage 42a, an oil passage 41b, and a check valve 183, a check valve 184, a check valve 185 that prevent oil from flowing into the accumulator 30 from the oil passage 42b. And a check valve 186 is provided. Moreover, EHA1 is provided with the relief valve 32 which prevents that the pressure of the oil which each distribute | circulates the oil path 41a and the oil path 42a becomes more than a setting pressure.

  Further, when the amount of oil stored in the accumulator 30 decreases, the oil can be supplied from an oil supply source connected to the oil supply path 60. Specifically, an oil supply path 60 is connected to the oil path 31 communicating with the accumulator 30. The oil supply path 60 is provided with a filter 61, a check valve 62, and an electromagnetic valve 63. Then, by energizing the electromagnetic valve 63, the oil supply source and the oil passage 31 communicating with the accumulator 30 can be communicated with each other. The flow of oil from the accumulator 30 to the oil supply source is blocked by the check valve 62. Further, the oil supply path 60 includes a relief valve 65 that discharges the oil to the tank 64 when the pressure of the oil flowing through the oil supply path 60 becomes equal to or higher than a set pressure.

  Further, an arm 25 is connected to the rod 23 of the EHA 1 via a rotation fulcrum 24, and the arm 25 is connected to a control surface 110 (for example, an aileron, etc.) of the aircraft 100 as shown in FIG. Flight control surfaces such as flaperons, spoilers, elevators, ladders, etc.). The control surface 110 is configured to be swingable by the EHA1. In addition to EHA 1, another actuator used for operation in the case of a failure of the EHA 1 is connected to the control surface 110.

  In FIG. 2, the aircraft 100 flies in the direction of arrow Z, and the control surface 110 receives a load due to air resistance in the direction of arrow Y1 or Y2 in FIG. Here, when the control surface 110 receives a load due to air resistance in the direction of arrow Y1, the rod 23 (see FIG. 1) receives the load in the direction of arrow X1 shown in FIG. Moreover, the rod 23 (refer FIG. 1) receives a load in the direction of the arrow X2 shown in FIG. 1, when the control surface 110 receives the load by an air resistance in the direction of the arrow Y2.

Next, the operation of the EHA 1 according to the first embodiment will be described.
In order to cause the rod 23 of the hydraulic cylinder 20 to generate an axial force in the direction of the arrow X2 in FIG. 1 (that is, an axial force that opposes the air resistance acting in the direction of the arrow Y1 in FIG. 2), the servo motor 11 Thus, the variable displacement pump 12 is driven to discharge oil to the oil passage 42a side. Then, the switching valve 50 is switched to the first switching position 50A. Thereby, oil is supplied to the oil supply chamber 20b through the oil passage 42a and the oil passage 42b, and an axial force in the direction of the arrow X2 can be generated in the rod 23. At this time, the oil in the oil supply chamber 20a is supplied to the variable displacement pump 12 via the oil passage 41b and the oil passage 41a.

  Further, by driving the variable displacement pump 12 to discharge oil to the oil passage 41a side, it is possible to generate an axial force on the rod 23 of the hydraulic cylinder 20 in the direction of the arrow X1 in FIG.

  In the EHA 1 according to the first embodiment, the pressure of oil discharged from the variable displacement pump 12 (hereinafter referred to as discharge pressure) is passed through the oil passage 18 (oil passage 18a, oil passage 18b, oil passage 18c). Acting on the piston 72. When the discharge pressure exceeds a predetermined pressure P1, the piston 72 moves in a direction (advancing direction) to narrow the second oil supply chamber 17b against the biasing force of the spring 74. As the discharge pressure increases, the amount of movement of the piston 72 in the advance direction increases. The predetermined pressure P1 is determined according to the biasing force of the spring 74.

  That is, as shown in FIG. 3 showing the relationship between the discharge pressure and the discharge volume of the variable displacement pump 12, the discharge volume is constant at Dmax until the discharge pressure reaches a predetermined pressure P1. When the discharge pressure exceeds a predetermined pressure P1, the discharge volume of the variable displacement pump 12 is proportionally decreased as the discharge pressure increases.

  Further, the EHA 1 is configured such that the relief valve 32 opens when the discharge pressure exceeds a predetermined pressure Pmax. Therefore, the discharge pressure does not exceed the predetermined pressure Pmax. In FIG. 3, when the discharge pressure is the pressure Pmax, the discharge volume D1 is shown to be about 20% of Dmax. However, D1 is set to 5 of Dmax according to the performance required for EHA1. If it is set between% and 70%, a sufficient effect can be obtained.

  When the discharge pressure decreases in a state where the discharge pressure is higher than the predetermined pressure P1, the piston 72 moves in the retracting direction and the first oil is supplied through the throttle passage 72a formed in the piston 72. The oil moves from the chamber 17a to the second oil supply chamber 17b.

  FIG. 4 shows the relationship between the axial force of the actuator (the axial force transmitted by the rod 23) and the operating speed of the actuator (the moving speed of the rod 23 in the hydraulic cylinder 20) in the EHA 1 according to the first embodiment. FIG. 5 is a schematic diagram showing the relationship between the axial force of the actuator and the motor current (current flowing through the servo motor 11). As a comparative example, the above relationship when the discharge volume of the variable displacement pump 12 is kept constant is also shown.

  As shown in FIG. 4, when the rotational speed of the servo motor 11 is controlled to be a predetermined rotational speed (for example, the maximum rotational speed), for example, when the axial force of the actuator becomes larger than F1, the actuator The operating speed of the is reduced proportionally. That is, the greater the air resistance acting on the control surface 110, the lower the operating speed of the actuator. The axial force F1 is an axial force of the actuator when the discharge pressure of the variable displacement pump 12 is a predetermined pressure P1.

  At this time, the motor current increases to the maximum value Imax and then decreases as the axial force of the actuator increases. Here, the torque required to drive the variable displacement pump 12 is proportional to the product of the axial force (ie, discharge pressure) of the actuator and the discharge volume. That is, for example, if the discharge volume is constant, the torque increases as the axial force of the actuator increases. If the axial force of the actuator is constant, the torque increases as the discharge volume increases.

  The EHA 1 of the first embodiment is configured such that the discharge volume decreases as the axial force of the actuator increases (that is, the discharge pressure increases). Therefore, at least a part of the increase in the torque due to the increase in the axial force of the actuator is offset by the decrease in the torque due to the decrease in the discharge volume. Thereby, the increase rate of the motor current until the axial force of the actuator reaches the predetermined axial force F2 can be reduced.

  Further, when the axial force of the actuator becomes larger than the predetermined axial force F2, the decrease in the torque due to the decrease in the discharge volume becomes larger than the increase in the torque due to the increase in the axial force of the actuator. Therefore, as the axial force of the actuator increases, the torque required to drive the variable displacement pump 12 decreases, and the motor current also decreases following the fluctuation of the torque.

  On the other hand, when the discharge volume is kept constant (comparative example), the operating speed of the actuator is kept constant even if the axial force of the actuator increases. At this time, the motor current increases proportionally as the axial force of the actuator increases. This is because the torque to be output by the servo motor 11 increases in proportion to the axial force of the actuator, and the motor current increases in proportion to the torque.

  As an example of this embodiment, when the actuator exhibits a predetermined maximum axial force Fmax (that is, when the discharge pressure is Pmax), the discharge volume D1 of the variable displacement pump 12 is when the axial force of the actuator is zero. The first discharge volume Dmax is about 20% of the first discharge volume Dmax. In this case, the maximum value Imax of the motor current can be reduced to half or less of the maximum value Imax ′ of the motor current when the discharge volume is constant (comparative example). In addition, according to the comparison in a state in which the actuator exhibits the predetermined maximum axial force Fmax, it is further reduced. The setting of D1 is changed according to the performance required for the actuator. For example, the effect can be obtained by setting D1 between 5% and 70% of Dmax, and the effect becomes larger as D1 is smaller than Dmax. Become.

  As described above, the hydraulic pressure supply device 10 according to the embodiment of the present invention includes the servo motor 11, the variable displacement pump 12 that is driven by the servo motor 11 and can discharge oil, and the servo motor 11. A motor controller 13 that controls the rotational speed to be a rotational speed, and a pump that controls the variable displacement pump 12 such that the discharge volume of the variable displacement pump 12 decreases as the discharge pressure of the variable displacement pump 12 increases. And a control device 14.

  According to this configuration, the discharge pressure of the variable displacement pump 12 can be increased without excessively increasing the current flowing through the servomotor 11. Furthermore, the flow rate of the oil discharged from the variable displacement pump 12 can be increased without excessively increasing the rotation speed of the servo motor 11.

  Further, in the hydraulic pressure supply device 10, the pump control device 14 is configured such that when the discharge pressure is equal to or higher than the predetermined pressure P1 and equal to or lower than the predetermined pressure Pmax, the variable displacement pump The variable displacement pump 12 is controlled so that the discharge volume of 12 decreases proportionally.

  According to this configuration, the relationship between the discharge pressure and the discharge volume of the variable displacement pump 12 is not complicated, and the control of the variable displacement pump 12 is facilitated.

  Further, in the hydraulic pressure supply device 10, the pump control device 14 is moved by the pressure of the oil discharged from the variable displacement pump 12, and the rod 73 and the piston that increase and decrease the discharge volume of the variable displacement pump 12. 72 and a spring 74 that urges the piston 72 against the pressure of oil acting on the piston 72.

  According to this configuration, the pump controller 14 that controls the variable displacement pump 12 so that the discharge volume of the variable displacement pump 12 decreases proportionally as the discharge pressure of the variable displacement pump 12 increases can be simplified. It can be realized by configuration.

  Further, the EHA 1 according to the first embodiment includes a hydraulic pressure supply device 10 and a hydraulic cylinder 20 that operates by receiving the working fluid output by the variable displacement pump 12.

  According to this configuration, since the hydraulic pressure supply device 10 can supply low pressure and high pressure oil to the hydraulic cylinder 20, a large axial force can be exhibited with a low current. Furthermore, since the flow rate of the oil discharged from the variable displacement pump 12 can be increased without excessively increasing the rotational speed of the servo motor 11, a large amount of oil is supplied to the hydraulic cylinder 20 at a low current. Thus, the rod 23 can be driven at a high speed. As described above, since the current flowing through the servo motor 11 can be suppressed and the heat generation of the servo motor 11 can be suppressed, the entire EHA 1 can be reduced in size and weight. Furthermore, the load of the motor control device 13 can be reduced and the reliability can be improved.

  The EHA 1 is used for driving a flight control control surface 110 provided on an aircraft wing (main wing, vertical tail, horizontal tail, etc.).

  During the flight of the aircraft, a high load due to air resistance continues to act on the control surface 110 provided on the wing of the aircraft. Therefore, in the stalled state, the hydraulic cylinder 20 that drives the control surface 110 is required to generate a large force against a load due to air resistance. On the other hand, for example, in a state where the load acting on the control surface 110 is small, such as a standby state before takeoff, it is desired to adjust the position of the control surface 110 at a higher operating speed. In this regard, EHA1 can supply high pressure oil with a low current to the hydraulic cylinder 20, so that power consumption in the stalled state can be reduced and heat generation of the servo motor 11 can be suppressed. Further, when the load acting on the control surface 110 is small, the speed at which the control surface 110 is driven can be increased.

  As described above, in an aircraft, when the load acting on the control surface 110 is small, the control surface 110 can be operated at high speed, and even when a large load is applied, the control surface 110 is resisted against the load. It is required to be configured to operate. The relationship between the load acting on the control surface 110 and the required operation speed of the control surface 110 is such that the operation speed decreases approximately proportionally as the load increases.

  In this regard, in the EHA 1 that drives the control surface 110 according to the first embodiment, the pump control device 14 allows the discharge pressure of the variable displacement pump 12 when the discharge pressure is equal to or higher than the predetermined pressure P1 and equal to or lower than the predetermined pressure Pmax. As the flow rate increases, the discharge volume of the variable displacement pump 12 decreases proportionally so as to satisfy the above-described relationship between the load acting on the control surface 110 and the required operating speed of the control surface 110. Thus, the variable displacement pump 12 is controlled. Therefore, the EHA 1 is particularly suitable for controlling the control surface 110.

  In the hydraulic pressure supply device 10, the variable displacement pump 12 is controlled so that the discharge volume becomes constant until the discharge pressure reaches the predetermined pressure P1, but the present invention is not limited to this case. For example, as shown in FIG. 5, the discharge volume may be reduced when the discharge pressure is generated. Further, as shown in FIG. 5, the discharge volume may be set to 0 at a predetermined pressure Pmax at which the relief valve 32 is opened.

(Second Embodiment)
Next, EHA2 which concerns on 2nd Embodiment of this invention is demonstrated. FIG. 6 is a diagram showing an EHA 2 according to the second embodiment of the present invention. The EHA 2 (electric actuator) according to the second embodiment is different from the EHA 1 in the first embodiment in the configuration of the pump control device in the hydraulic pressure supply device. Since other configurations are the same as those of the first embodiment, the same members are denoted by the same reference numerals and description thereof is omitted.

The pump control apparatus 200 in the EHA 2 includes a spool valve 220 (pressure adjusting unit) between the variable displacement pump 12 and the tilt angle adjusting cylinder 17.
That is, the pump control apparatus 200 according to the second embodiment is provided in the inclination angle adjustment cylinder 17, the oil passage 41 a that communicates the oil passage 41 a and the oil passage 42 a, and the inclination angle adjustment cylinder 17, and the oil passage 230. A check valve 181, a check valve 182, and a spool valve 220. The oil passage 230 includes an oil passage 18a branched from the oil passage 41a, an oil passage 18b branched from the oil passage 42a, an oil passage 230a in which these join and communicate with the spool valve 220, and a spool valve 220 and an inclination angle adjustment. The oil passage 230 b communicates with the cylinder 17, and the oil passage 230 c communicates between the spool valve 220 and the oil passage 43. The oil passage 230a communicates with a pilot chamber for switching the spool valve 220 to the second switching position 220B. Further, the biasing force of the spring acts in the direction of switching the spool valve 220 to the first switching position 220A.

  When the oil pressure of the oil passage 230a is smaller than the predetermined pressure P2, the spool valve 220 communicates the oil passage 230b and the oil passage 230c connected to the oil passage 43, and the first switching that blocks the oil passage 230a. When switching to the position 220A and the oil pressure of the oil passage 230a is equal to or higher than the predetermined pressure P2, the oil passage 230a and the oil passage 230b communicating with the first oil supply chamber 17a of the tilt angle adjusting cylinder 17 are communicated. Then, it switches to the second switching position 220B that blocks the oil passage 230c. The spool valve 220 is configured so that the oil passage 230a, the oil passage 230b, and the oil passage 230c are temporarily connected when the spool position is switched.

According to this configuration, the discharge pressure of the variable displacement pump 12 acts on the spool valve 220 via the oil passage 230a. If the pressure (discharge pressure) of the oil passage 230a is smaller than the predetermined pressure P2, the spool valve 220 is held at the first switching position 220A. In this case, the piston 72 of the tilt angle adjusting cylinder 17 is held at a fixed position.
On the other hand, when the discharge pressure increases and the pressure in the oil passage 230a reaches a predetermined pressure P2, the spool valve 220 is switched to the second switching position 220B. At this time, since the oil passage 230a, the oil passage 230b, and the oil passage 230c are temporarily connected, it is possible to prevent the pressure acting on the piston 72 of the inclination angle adjusting cylinder 17 from rapidly increasing. Thereafter, the piston 72 of the tilt angle adjusting cylinder 17 moves to the end position of the movable range in the advance direction, and is held at that position.

  Further, when the discharge pressure is decreased from the state of P2 or higher to a pressure smaller than P2, the spool valve 220 is switched from the second switching position 220B to the first switching position 220A. Then, the piston 72 moves in the retreat direction while discharging the oil from the first oil supply chamber 17a through the oil passage 230b. Thereby, the movement of the piston 72 in the retracting direction is quickly performed.

  As described above, the EHA 2 according to the second embodiment can adjust the pressure acting on the piston 72 by providing the spool valve 220 between the variable displacement pump 12 and the piston 72. In this embodiment, since the pressure acting on the piston 72 from the variable displacement pump 12 can be reduced, it is possible to prevent the pressure acting on the piston 72 from rapidly increasing. Thereby, it can suppress that the discharge volume of the variable displacement pump 12 becomes unstable. Further, by adjusting the pressure with the spool valve 220, the degree of freedom in designing the tilt angle adjusting cylinder 17 can be increased.

(Third embodiment)
Next, the EHA 3 according to the third embodiment will be described.
FIG. 7 is a diagram showing an EHA 3 according to the third embodiment of the present invention. FIG. 8 is a diagram showing the relationship between the discharge pressure and the discharge volume of the variable displacement pump shown in FIG.
The EHA 3 (electric actuator) according to the third embodiment is different from the EHA 2 in the second embodiment in the configuration of the pump control device in the hydraulic pressure supply device. Since other configurations are the same as those of the second embodiment, the same members are denoted by the same reference numerals and description thereof is omitted.

The pump control device 300 in the EHA 3 includes a switching valve 320 between the variable displacement pump 12 and the tilt angle adjusting cylinder 370.
In other words, the pump control device 300 according to the third embodiment is provided in the inclination angle adjustment cylinder 370, the oil passage 330 that communicates the oil passage 41 a and the oil passage 42 a, and the inclination angle adjustment cylinder 370, and the oil passage 330. The check valve 181 and the check valve 182 and the switching valve 320 are provided. The oil passage 330 includes an oil passage 18a branched from the oil passage 41a, an oil passage 18b branched from the oil passage 42a, an oil passage 330a in which these join and communicate with the switching valve 320, and a switching valve 320 and an inclination angle adjustment. An oil passage 330 b that communicates with the cylinder 370 and an oil passage 330 c that communicates the switching valve 320 and the oil passage 43 are provided. The oil passage 330a communicates with a pilot chamber for switching the switching valve 320 to the second switching position 320B. The oil passage 330b communicates with a pilot chamber for switching the switching valve 320 to the first switching position 320A.

  When the pressure difference ΔP obtained by subtracting the oil pressure of the oil passage 330b communicating with the first oil supply chamber 370a of the inclination angle adjusting cylinder 370 from the oil pressure of the oil passage 330a is smaller than the predetermined pressure difference ΔP3. When the pressure difference ΔP is equal to or greater than the predetermined pressure difference ΔP3, the oil path 330b and the oil path 330c connected to the oil path 43 are communicated and switched to the first switching position 320A that blocks the oil path 330a. Then, the oil passage 330a and the oil passage 330b are communicated with each other via the throttle passage, and the second switching position 320B is switched to block the oil passage 330c. The predetermined pressure difference ΔP3 is determined according to the urging force of a spring that urges the switching valve 320 to be held at the first switching position 320A.

  The tilt angle adjusting cylinder 370 includes a cylinder body 371, a piston 372 (operation member) disposed in the cylinder body 371, a rod 373 (operation member) integrally engaged with the piston 372, and the piston 372. And a spring 374 (elastic member) for urging. The cylinder body 371 and the piston 372 form a first oil supply chamber 370a to which oil is supplied via the oil passage 330b and a second oil supply chamber 370b that can discharge oil to the oil passage 43. .

  The spring 374 in the tilt angle adjusting cylinder 370 is a spring that urges the piston 372 with a force that can move the piston 372 in the retracting direction when no hydraulic pressure is generated in the first oil supply chamber 370a. . And when oil_pressure | hydraulic is transmitted to the 1st oil supply chamber 370a, it is comprised so that the piston 372 may move to the most extreme position of the range which can move in the advance direction. In the state where the piston 372 has moved to the extreme end position in the advancing direction, the second discharge volume D3 of the variable displacement pump 12 is about 50% of the first discharge volume Dmax before the piston 372 has moved. It is comprised so that it may become. The second discharge volume D3 is not limited to about 50% of the first discharge volume Dmax, and may be changed to a discharge volume capable of discharging at least a predetermined amount of oil.

According to this configuration, the discharge pressure of the variable displacement pump 12 acts on the switching valve 320 via the oil passage 330a. In the state where the variable displacement pump 12 is not driven, the discharge pressure does not act on the switching valve 320, so that the switching valve 320 is held at the first switching position 320A. In this case, the piston 372 of the tilt angle adjusting cylinder 370 is held at a fixed position. Therefore, as shown in FIG. 8, the discharge volume of the variable displacement pump 12 is constant at Dmax until the discharge pressure from the variable displacement pump 12 reaches a predetermined pressure P3. The predetermined pressure P3 is a pressure at which the pressure difference ΔP becomes the predetermined pressure difference ΔP3.
On the other hand, when the discharge pressure increases to the predetermined pressure P3 and the pressure difference ΔP reaches the predetermined pressure difference ΔP3, the second that communicates the oil passage 330a and the oil passage 330b via the throttle passage. It switches to the switching position 320B. In this case, the piston 372 of the tilt angle adjusting cylinder 370 moves to the end position of the movable range in the advance direction and is held at that position. Therefore, as shown in FIG. 8, when the discharge pressure is P3 or more, the discharge volume of the variable displacement pump 12 is constant at D3.

  Further, when the pressure difference ΔP decreases from a state where the pressure difference ΔP is equal to or larger than the predetermined pressure difference ΔP3 to a pressure difference smaller than ΔP3, the switching valve 320 is switched to the first switching position 320A. Then, the piston 372 moves in the retracting direction while discharging the oil from the first oil supply chamber 370a through the oil passage 330b. As a result, the piston 372 is quickly moved in the retracting direction.

  As described above, the EHA 3 according to the third embodiment has the servo motor 11, the variable displacement pump 12 that is driven by the servo motor 11 and can discharge oil, and the servo motor 11 has a set rotation speed. When the discharge pressure of the motor control device 13 and the variable displacement pump 12 controlled as described above is smaller than the predetermined pressure P3, the variable displacement pump is set so that the discharge volume of the variable displacement pump 12 becomes the first discharge volume Dmax. When the pump 12 is controlled and the discharge pressure of the variable displacement pump 12 reaches the predetermined pressure P3, the discharge volume of the variable displacement pump 12 becomes the second discharge volume D3 which is half of the first discharge volume Dmax. And a pump control device 300 for controlling the variable displacement pump 12.

  According to this configuration, the variable displacement pump 12 is controlled so as to have the second discharge volume D3, thereby increasing the discharge pressure of the variable displacement pump 12 without excessively increasing the current flowing through the servo motor 11. be able to. Furthermore, by controlling the variable displacement pump 12 so as to have the first discharge volume Dmax, the flow rate of oil discharged from the variable displacement pump 12 can be reduced without excessively increasing the rotation speed of the servo motor 11. Can be increased.

  In EHA3, the pump control device 300 moves due to the pressure of the oil discharged from the variable displacement pump 12, and moves the piston 372 and the rod 373 to increase the discharge volume of the variable displacement pump 12. A spring 374 that urges the piston 372 against the pressure of oil acting on the piston 372 and a flow that is provided between the variable displacement pump 12 and the piston 372 and communicates the variable displacement pump 12 and the piston 372. There is provided a switching valve 320 that can be switched to a first switching position 320A for blocking the path, and a second switching position 320B for communicating the variable displacement pump 12 and the piston 372. The switching valve 320 is held at the first switching position 320A when the discharge pressure of the variable displacement pump 12 is smaller than the predetermined pressure P3, and the second when the discharge pressure of the variable displacement pump 12 reaches the predetermined pressure P3. It switches to the switching position 320B.

  According to this configuration, when the discharge pressure of the variable displacement pump 12 is smaller than the predetermined pressure P3, the variable displacement pump 12 is controlled so that the discharge volume of the variable displacement pump 12 becomes the first discharge volume Dmax. When the discharge pressure of the variable displacement pump 12 reaches a predetermined pressure P3, the pump controller 200 that controls the variable displacement pump 12 so that the discharge volume of the variable displacement pump 12 becomes the second discharge volume D3. This can be realized with a simple configuration.

  In the third embodiment, the oil passage 330b communicates with a pilot chamber for switching the switching valve 320 to the first switching position 320A. However, the configuration is not limited to this case, and the pilot chamber is not provided. It is good. In this case, the pressure acting from the oil passage 330a on the pilot chamber for switching the switching valve 320 to the second switching position 320B, the spring biasing force acting in the direction of switching the switching valve 320 to the first switching position 320A, Based on the above, the switching valve 320 is switched.

(Fourth embodiment)
Next, EHA4 according to the fourth embodiment will be described.
FIG. 9 is a diagram showing an EHA 4 according to the fourth embodiment of the present invention. FIG. 10 is a diagram showing the relationship between the discharge pressure and the discharge volume of the variable displacement pump 12 shown in FIG. The EHA 4 (electric actuator) according to the fourth embodiment is different from the EHA 3 according to the third embodiment in the configuration of the pump control device in the hydraulic pressure supply device. Since other configurations are the same as those of the third embodiment, the same members are denoted by the same reference numerals and description thereof is omitted.

The pump control device 400 in the EHA 4 includes an electromagnetic switching valve 420 provided between the variable displacement pump 12 and the tilt angle adjusting cylinder 370, and a valve switching device 421 that can be switched by energizing the electromagnetic switching valve 420. It is equipped with. (Valve switching device 421 can also be incorporated in motor control device 13 as required.)
In other words, the pump control device 400 of the fourth embodiment is provided in the inclination angle adjustment cylinder 370, the oil passage 430 that connects the oil passage 41 a and the oil passage 42 a, and the inclination angle adjustment cylinder 370, and the oil passage 430. The check valve 181 and the check valve 182, the electromagnetic switching valve 420, and the valve switching device 421 are included. The oil passage 430 includes an oil passage 18a branched from the oil passage 41a, an oil passage 18b branched from the oil passage 42a, an oil passage 430a that joins and communicates with the electromagnetic switching valve 420, and an electromagnetic switching valve 420 that is inclined. The oil passage 430b communicates with the angle adjusting cylinder 370, and the oil passage 430c communicates with the electromagnetic switching valve 420 and the oil passage 43.

  In the non-energized state, the electromagnetic switching valve 420 communicates with the oil passage 430b and the oil passage 430c, is held at the first switching position 420A that blocks the oil passage 430a, and is energized from the valve switching device 421. The oil passage 430a and the oil passage 430b communicate with each other via the throttle passage, and the second switching position 420B is switched to block the oil passage 430c.

  The valve switching device 421 is configured to energize the electromagnetic switching valve 420 when a predetermined time elapses after the rotation speed of the servo motor 11 is stabilized.

  As a result, the electromagnetic switching valve 420 is held at the first switching position 420A until a predetermined time elapses after the rotation speed of the servo motor 11 is stabilized. In this case, the piston 372 of the tilt angle adjusting cylinder 370 is held at a fixed position. Therefore, as shown in FIG. 10, the discharge volume of the variable displacement pump 12 is constant at Dmax until a predetermined time elapses after the rotation speed of the servo motor 11 is stabilized. When a predetermined time has elapsed from the start of rotation of the servo motor 11, the servo motor 11 switches to the second switching position 420B. In this case, the piston 372 of the tilt angle adjusting cylinder 370 moves to the end position of the movable range in the advance direction and is held at that position. Therefore, as shown in FIG. 10, after a predetermined time has elapsed since the rotation speed of the servo motor 11 is stabilized, the discharge volume of the variable displacement pump 12 becomes constant at D3.

  Further, when the rotation of the servo motor 11 is changed again after a predetermined time has elapsed after the rotation speed of the servo motor 11 is stabilized, the electromagnetic switching valve 420 is switched to the first switching position 420A. Then, the piston 372 moves in the retracting direction while discharging the oil from the first oil supply chamber 370a through the oil passage 430b. As a result, the piston 372 is quickly moved in the retracting direction.

  As described above, the EHA 4 according to the fourth embodiment has the servo motor 11, the variable displacement pump 12 that is driven by the servo motor 11 and can discharge oil, and the servo motor 11 has a set rotation speed. The variable displacement pump so that the discharge volume of the variable displacement pump 12 becomes the first discharge volume Dmax until a predetermined time elapses after the rotation speed of the servo motor 11 is stabilized. 12 and a pump control device 400 that controls the variable displacement pump 12 so that the discharge volume of the variable displacement pump 12 becomes the second discharge volume D3 when a predetermined time has elapsed from the start of rotation of the servo motor 11. .

  According to this configuration, the discharge pressure of the variable displacement pump 12 can be increased without excessively increasing the current flowing through the servomotor 11 after a predetermined time has elapsed since the rotation speed of the servomotor 11 has stabilized. it can. Furthermore, before the predetermined time has elapsed since the rotation speed of the servo motor 11 is stabilized, the flow rate of the oil discharged from the variable displacement pump 12 is increased without excessively increasing the rotation speed of the servo motor 11. be able to.

  In EHA4, the pump control device 400 is moved by the pressure of the oil discharged from the variable displacement pump 12, and moves the piston 372 and the rod 373 to increase or decrease the discharge volume of the variable displacement pump 12. A spring 374 that urges the piston 372 against the pressure of oil acting on the piston 372 and a flow that is provided between the variable displacement pump 12 and the piston 372 and communicates the variable displacement pump 12 and the piston 372. There is provided an electromagnetic switching valve 420 that can be switched to a first switching position 420A for blocking the path, and a second switching position 420B for communicating the variable displacement pump 12 and the piston 372. The electromagnetic switching valve 420 is held at the first switching position 420A until a predetermined time elapses after the rotational speed of the servo motor 11 is stabilized by the valve switching device 421, and after the rotational speed of the servo motor 11 is stabilized. When the predetermined time elapses, the position is switched to the second switching position 420B.

  According to this configuration, the variable displacement pump 12 is controlled so that the discharge volume of the variable displacement pump 12 becomes the first discharge volume Dmax until a predetermined time elapses after the rotation speed of the servo motor 11 is stabilized, When a predetermined time elapses after the rotation speed of the servo motor 11 is stabilized, the pump controller 400 that controls the variable displacement pump 12 so that the discharge volume of the variable displacement pump 12 becomes the second discharge volume D3 is simplified. Can be realized with a simple configuration.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims.

(1) The variable displacement pump is not limited to a swash plate type axial piston pump that rotates a cylinder block, but a rotary swash plate type piston pump that rotates a swash plate. An oblique axis type piston pump and other variable displacement pumps can be used. Further, in the swash plate type pump, it is possible to use a structure in which bearings are embedded in the swash plate without using a shoe (slipper) and the piston head contact surface is allowed to rotate.

(2) As in the third embodiment and the fourth embodiment, the discharge volume is not limited to two stages, but may be changed to a plurality of stages.

(3) The pump control unit is not limited to the case of using the tilt angle adjusting cylinder 17 or the like that is operated by the pressure of the oil discharged from the variable displacement pump. For example, the discharge volume of the variable displacement pump may be changed based on a measurement result from a hydraulic pressure measuring device that measures the discharge pressure of the variable displacement pump.

(4) By providing a damper on the piston 72 of the tilt angle adjusting cylinder 17, a rapid movement of the piston 72 can be suppressed, and safety can be improved.

(5) The variable speed electric motor can use various motors such as a surface magnet type or embedded magnet type brushless motor, a switched reluctance motor, a synchronous motor, and a brushed motor. Further, the motor control unit for controlling the variable speed motor may be configured integrally with the variable speed motor or may be provided separately.

(6) The electric actuator of the present invention is not limited to the case where it is used for driving the control surface of a wing of an aircraft, but can be applied to other uses. Moreover, the working fluid supply apparatus of the present invention is not limited to the case where the working fluid is input and actuated by an actuator, and can be applied to other uses.

(7) The present invention can be applied not only to the configuration using oil as the working fluid but also to a compressed air supply device using air as the working fluid.

1 EHA (electric actuator)
10 Hydraulic supply device (working fluid supply device)
11 Servo motor (variable speed electric motor)
12 Variable displacement pump 13 Motor controller (motor controller)
14 Pump controller (pump controller)
17 Inclination Angle Adjustment Cylinder 71 Cylinder Body 72 Piston (Operating Member)
73 Rod (actuating member)
74 Spring (elastic member)
100 Aircraft 110 Control surface 220 Spool valve (pressure adjustment part)

Claims (4)

A variable speed electric motor,
A variable displacement pump driven by the variable speed motor and capable of discharging a working fluid;
An electric motor controller that controls the variable speed electric motor so as to achieve a desired rotational speed;
When the discharge pressure of the variable displacement pump is lower than a predetermined pressure, the variable displacement pump is controlled so that the discharge volume of the variable displacement pump becomes the first discharge volume, and the variable displacement pump A pump controller that controls the variable displacement pump such that when the discharge pressure reaches the predetermined pressure, the discharge volume of the variable displacement pump becomes a second discharge volume smaller than the first discharge volume;
An actuator that is operated by receiving the working fluid output by the variable displacement pump;
An electric actuator comprising:
The pump control unit is driven by the discharge pressure of the variable displacement pump, and has an inclination angle adjustment cylinder that increases or decreases the discharge volume of the variable displacement pump ,
The tilt angle adjusting cylinder is driven so that the discharge volume decreases as the axial force of the actuator increases, and when the axial force of the actuator becomes larger than a predetermined axial force, the axial force of the actuator is reduced. An electric actuator that is driven such that a decrease in the torque due to a decrease in the discharge volume is greater than an increase in torque required to drive the variable displacement pump due to the increase. The tilt angle adjusting cylinder includes:
An operating member that moves by the action of the pressure of the working fluid discharged from the variable displacement pump to increase or decrease the discharge volume of the variable displacement pump;
An elastic member for biasing the operating member against the pressure of the working fluid acting on the operating member;
With
The pump controller
A first switching position provided between the variable displacement pump and the operating member and blocking a flow path communicating the variable displacement pump and the operating member; the variable displacement pump and the operating member; And a switching valve that can be switched to a second switching position that communicates with
The switching valve is held at the first switching position when the discharge pressure of the variable displacement pump is smaller than the predetermined pressure, and the discharge valve of the variable displacement pump reaches the predetermined pressure when the discharge pressure reaches the predetermined pressure. The electric actuator according to claim 1, wherein the electric actuator is switched to a two-switching position. The pump controller
The electric actuator according to claim 2 , further comprising a pressure adjusting unit that is provided between the variable displacement pump and the operation member and adjusts the pressure of the working fluid that acts on the operation member from the variable displacement pump. The electric actuator according to any one of claims 1 to 3, wherein the electric actuator is used for driving a control surface of a wing of an aircraft.

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