KR20010064450A - Oil hydraulic serve actuator of absolute location sensing - Google Patents

Abstract

PURPOSE: An absolute position sensing type hydraulic servo actuator is provided to realign a system at an absolute neutral position with neutral position information memorized by an absolute position sensor embedded inside a piston if the system is reoperated. CONSTITUTION: In a pair of actuators(4,5) installing a piston(7) inside a cylinder(6) to be connected with a housing(9) for connecting a rocket engine and an engine mount, an absolute position sensing type hydraulic servo actuator includes an absolute position sensor installed inside the housing and an earth end assembled body(10) for generating pulses for detecting positions, and a magnet installed at the end of the piston by a fixing member for generating a magnetic field.

Description

Oil hydraulic serve actuator of absolute location sensing

The present invention is an absolute position-sensing hydraulic servo actuator and method used in a gimbal engine position control hydraulic drive device that controls the attitude and trajectory of the rocket by adjusting the thrust direction of the engine as a device applied to a scientific observation rocket and a satellite projectile. It is about.

The liquid engine rocket, which uses liquid fuel and oxidant as propellant, controls the attitude of the rocket's pitch axis and yaw axis by following the trajectory by controlling the thrust direction by rotating the engine connected to the gimbal engine shaft in the pitch axis and yaw axis direction. .

The Gimbal Engine Position Control Hydraulic Actuator which removes the thrust direction of the Gimbal Engine for accurate rocket posture and trajectory control on the pitch axis and yaw axis direction is precise and responsive. One set each.

In the case of a general hydraulic servo actuator for position control, the current feedback information is fed back to the controller by a position feedback sensor.

Since the servo system is controlled to reduce the error signal comparing the reference control command and the feedback signal, the accuracy of the initial position information of the feedback position sensor is very important.

Therefore, the general position detection sensor is a passive device that requires power, so if the system power is removed and then applied again, the initial position information is lost. Therefore, the general hydraulic servo drive system for position control is equipped with a separate device for initial position setting. It is.

However, in the case of the hydraulic servo operating system for position control applied to the gimbal engine drive of the liquid engine rocket, if a number of separate devices are installed for initial position setting, not only the complexity of the system, but also the weight and volume increase, and the worst operation Increasing environmental and applied components can lead to a decrease in system reliability.

In addition, due to the rocket launch scenario, the gimbal engine drive must be operated 10 to 20 seconds before launch. Therefore, the hydraulic drive is operated in a steady state during this short time to perform the self-diagnosis program, as well as the ratio of the gimbal engine caused by the rocket tilt and disturbance. Performing a calibration test to realign the alignment error places a heavy burden on the rocket launch.

The present invention assembles the hydraulic servo actuator for driving the Gimbal engine to the engine mount and the engine connection part so that the rocket gas shaft and the gimbal engine shaft coincide with each other during the initial assembly of the rocket engine drive unit. If set, the system can be rearranged to the absolute neutral position from the neutral position information stored by the absolute position sensor even when the system is restarted.

The servo actuator of the present invention incorporates the absolute position sensor inside the piston of the actuator, and adjusts the gain according to the neutral position sensor to the absolute position sensor after initial setting of the kinematic neutral position.

The present invention provides an actuator for connecting a rocket engine and an engine mount by installing a piston into a cylinder to which a housing is connected, and installing an absolute position sensor that generates a pulse for detecting a position inside the housing and the earth end assembly. And, it is characterized in that the magnet to generate a magnetic field at the end of the piston to be rearranged to a predetermined neutral position.

1 is an installation state of the hydraulic servo actuator according to the present invention

2 is a front view of a hydraulic servo actuator according to the present invention.

3 is a side view of the hydraulic servo actuator according to the present invention;

4 is a cross-sectional view taken along line A-A of the hydraulic servo actuator according to the present invention;

* Explanation of symbols for the main parts of the drawings

1: rocket engine 2: gimbal engine shaft

3: engine mount 4: pitch axis control actuator

5: yaw axis control actuator 6: cylinder

7: piston 8: absolute position sensor

9 housing 10 earth end assembly

11: knuckle ring 12: magnet

13: Servo Valve 14: Rod End Bearing

According to the present invention, a pitch shaft control actuator 4 is provided on an engine mount 3 and a pitch shaft, and a yaw shaft control actuator 5 is provided on a yaw shaft.

A piston 7 inserted and operated inside the cylinder 6 and driven by a driving force applied to the outer servo valve 13 and having a rod end bearing 4 connected to a pitch shaft or a yaw shaft at a protruding portion is provided. Is installed.

The inner end of the piston 7 is fixed to the mark net 12 for generating a magnetic field for position identification using a fixing member such as a screw.

After the housing 9 is fixed to the cylinder 6, the earth end assembly 10 is connected through the knuckle ring 11.

The absolute position sensor 8 is installed inside the housing 9 so as to pass through the magnet 12 to the inside of the piston 7.

In the initial assembly of the actuators (4) (5), the rocket gas shaft and the gimbal engine shaft (2) are assembled to the pitch shaft and the yaw shaft of the engine mount (3) and the rocket engine (1).

After assembling the actuators (4) and (5), the neutral position of the piston (7) and the state of the piston (7) are completely press-fitted and extruded while the drive system is operated by applying the power to the absolute position sensor (8). Remember the position of power supply and remove power of drive system.

When power is reapplied in the drive system, the magnet 12 generates a magnetic field for position identification, and generates a pulse for position detection in the body of the absolute position sensor 8.

When the magnetic field generated by the pulse for the position detection of the absolute position sensor 8 and the external magnetic field generated by the magnet 12 meet, a distorted pulse is generated.

By detecting the time when the distorted pulse returns to the body of the sensor, the position of the piston 7 or the posture of the gimbal engine is detected.

Based on this principle, the hydraulic servo actuator for position control of the Gimbal engine is mounted on the projectile and moved to the Gimbal Engine Drive System even when the Gimbal Engine's posture changes due to the movement of the Gimbal Engine, or when the Gimbal Engine is changed due to the installation of another system. When over-power is applied, the system can be rearranged from the neutral position information stored by the absolute position sensor 8 to the absolute neutral position, and the initial position can be automatically recognized and restored.

That is, when the actuator (4) (5) is installed, the absolute neutral position of the piston (7) is memorized, and when the pulse of the absolute position sensor (8) meets the magnetic field of the magnet (12), the position of the piston (7) or gimbal If the engine posture is not matched, the hydraulic pressure is supplied to the servo valve 13 to drive the piston 7 so as to automatically recognize the initial position and restore it.

Therefore, the gimbal engine drive according to the rocket launch scenario must be operated 10 to 20 seconds before the launch, so that the misalignment error of the gimbal engine can be automatically restored during this short time.

When described in more detail through each process of the present invention below, when the control actuator (4) (5) is initially installed by applying power to the absolute position sensor 8, the neutral position of the piston (7) and press-in and extrude The location memory process of remembering the state of the closed state,

A pulse generation process of generating a pulse for position detection in the absolute position detection sensor 8,

When the magnetic field generated by the position detection pulse and the external magnetic field generated by the magnet 12 installed at the end of the piston 7 meet, a distorted pulse is generated and the distorted pulse is the body of the absolute position sensor 8. A position detection process of detecting the position of the piston 7 or the position of the gimbal engine by detecting the time to return to

Once the position is known, the initial position can be recognized and restored to offset the initial error that can occur in the rocket posture control and maximize the launch stability.

The present invention not only reduces the complexity, weight and mounting space of the system according to the installation of a separate device for initial positioning by embedding the absolute position sensor inside the piston of the actuator, but also reduces the reliability of the system by increasing the number of applied parts. Can be prevented.

The present invention is to remove the burden of performing a calibration test to realign the misalignment error of the gimbal engine caused by the rocket tilt and disturbance since the operation time of the gimbal engine drive according to the rocket launch scenario is short and impending.

The present invention memorizes the absolute neutral position when the actuator is first mounted on the projectile, before the launch even when the posture of the gimbal engine is changed due to the installation of the actuator on the projectile, moving or inclined for tilted firing, or by mounting of another system. The initial position is recognized and restored in a short time.

Claims (1)

In the actuator (4) (5), in which a piston (7) is installed inside the cylinder (6) to which the housing (9) is connected, connecting the rocket engine (1) and the engine mount (3), An absolute position sensor 8 for generating a pulse for position detection is installed in the housing 9 and the earth end assembly 10, and a magnet 12 generating a magnetic field at the end of the piston 7 is provided. Absolute position sensing hydraulic servo actuator, characterized by the installation.