JPH06201817A - Control device of sensor angle - Google Patents

Abstract

PURPOSE:To prevent noise from being mixed by supplying one part of a rotation command supplied to a first electric motor also to a second electric motor and then providing a circuit for canceling the angle change around the other axis generated due to angle control around one axis of the crossed two axes. CONSTITUTION:Pulse motors 18 and 19 for controlling turning angle and depression angle are controlled by drive pulses P1 and P2, respectively, thus controlling the direction of a transmission/reception wave surface 30a of a transducer 30. When only the turning angle is tried to be controlled by the motor 18. a follower bevel gear 22 turns along with the transducer 30, the engagement with a drive bevel gear 21 changes, and the depression angle also changes. Therefore. one part of the pulse P1 supplied to the motor 18 is supplied also to the motor 19 via a cancellation circuit with an N divider and an adder, thus canceling the change in the depression angle due to turning of the gear 22. Neither a slip ring 23 nor a brush 24 is used for supplying current to the motor 18 in this structure, thus preventing noise from being generated at the signal of the transducer 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor angle control device used as a scanning mechanism or a tracking mechanism for sensors such as sonars and antennas.

[0002]

2. Description of the Related Art As a typical example of this type of control device, there is a sonar scanning mechanism for detecting a fish school by radiating an ultrasonic beam from the ship's bottom into the water and receiving the reflected wave.

Sonar scanning methods are roughly classified into mechanical scanning and electronic scanning. In the mechanical scanning method, as shown in FIGS. 6 to 8, by rotating a transducer mounted on the bottom of the ship a, the transmitting / receiving direction of the thin ultrasonic beam b is changed, that is, transmitting / receiving → rotation. The fish school is detected from the reflected wave obtained by repeating the operations of transmitting / receiving waves → rotating, and the detected information is displayed in PPI. Here, as shown in FIG. 6, when the ultrasonic beam b is horizontally swirled, only fish near the sea surface can be detected. Therefore, it is necessary to detect a fish in the middle layer between the sea surface and the sea floor. Needs to radiate the ultrasonic beam b in the depression direction, as shown in FIG. The depression angle θ in this case is set by the limit of the detection distance due to attenuation and refraction of the ultrasonic beam in seawater and the water depth to the seabed. When detecting a school of fish in the direction of the vertical cross section, as shown in FIG. 8, the fish is fixed in the turning direction and the transmitting / receiving direction of the ultrasonic beam b is rotated only in the depression direction.

The mechanical scanning as described above is conventionally performed by an angle control device as shown in FIG. A transducer 1 for performing mutual conversion between a high frequency voltage and an ultrasonic wave is supported by a frame 3 via a horizontal rotary shaft 2, and a depression angle control motor 4 such as a pulse motor attached to one side of the frame 3 is provided. Is rotated around the rotation axis 2 to control the depression angle of the wave transmission / reception surface 1a. The frame 3 is
The rotation force of a swing angle control motor 6 composed of a pulse motor mounted on a housing (not shown) is suspended via a vertical rotation shaft 5 and is transmitted around a rotation shaft 5 by means of a gear 7. It is rotated, and thereby the turning angle of the wave transmitting / receiving surface 1a of the transducer 1 is controlled. The input / output of high-frequency electric signals to / from the transducer 1 and the supply of the driving current and the depression angle control signal to the depression angle control motor 4 are carried out by the slip ring 8 mounted on the circumference of the rotary shaft 5 and the sliding contact with the slip ring 8. It is performed through the brush 9.

The entire structure including the transducer 1, the frame 3, the depression angle control motor 4 and the turning control motors 6 is covered with a protective dome (not shown) protruding from the bottom of the ship,
The inside of the dome is filled with a medium such as oil whose acoustic impedance is similar to that of seawater outside the dome.

[0006]

According to the above conventional control device, since the depression angle control motor 4 is turned together with the frame body 3, the inertial load of the turning angle control motor 6 for controlling the turning angle of the transducer 1 is large. As a result, there are problems that high-speed turning becomes difficult and a large-sized motor with large torque is required. Further, the number of the slip rings 8 and the brushes 9 which are brought into sliding contact with the slip rings 8 is increased by the amount of the power feeding path to the depression angle control motor 4, and the depression angle control motor 6 is provided in the signal system to the transducer 1 passing through the slip rings 8. There is a problem that noise associated with the drive current to the device may be mixed.

[0007]

A sensor angle control device according to the present invention has a frame which holds a sensor such as a transducer rotatably, and a state where the frame has a common axis and can rotate independently of each other. A first and a second rotation shaft extending at
A power transmission mechanism such as a bevel gear, a worm gear, a crown gear or the like for transmitting the rotational force of the second rotating shaft to a rotational force in the orthogonal direction and transmitting the same to a sensor supported by the frame, and the first rotating shaft. A first electric motor that controls the angle around one of the two orthogonal axes of the sensor by rotating the frame through the power transmission mechanism by rotating the second rotating shaft. A second electric motor for controlling the angle of the sensor around the other of the two orthogonal axes, and a part of the rotation command supplied to the first electric motor is also supplied to the second electric motor to achieve the orthogonality. And a canceling circuit for canceling a change in the angle around the other of the two axes that occurs with the control of the angle around the other of the two axes.

[0008]

In the case where the control device of the present invention is applied to a sonar, a transducer is rotatably held by a frame body, and first and second control means for controlling a turning angle and a depression angle of the transducer. Rotating shafts of the same extend in a state of having a common axis and being rotatable independently of each other. The rotational force applied to the first rotary shaft by the first electric motor is directly transmitted to the frame body without changing its rotational direction and changes the turning angle of the transducer held in the frame body. On the other hand, the amount of rotation given to the second rotating shaft by the second electric motor is transmitted to the transducer while being converted into the rotational force in the orthogonal direction by the power transmission mechanism such as a bevel gear, and is orthogonal to the turning angle. Change the depression angle of the transducer. First,
Since the rotational force of the second electric motor is transmitted to the sensor via the first and second rotating shafts that extend independently of each other, the electric power of one electric motor becomes a load of the other electric motor. Is eliminated.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sensor angle control device according to the present invention will be described below as an example in which it is applied to a scanning mechanism of a sonar for detecting fish school on a ship. 1 and 2, reference numeral 10 is a housing attached to the bottom portion of a ship, 11 is a frame body arranged below the housing 10 to rotatably support a transducer 30 via a horizontal shaft 12, and 13 is a frame body. It is a cylindrical rotation shaft that rotatably holds the frame body 11. This cylindrical rotating shaft 13
Is a shaft hole 1 formed in the lower end wall 10a of the housing 10.
4 and the thrust bearing 15
The housing 1 is rotatably supported via a gear train including a driven gear 16 provided at the upper end of the driven gear 16 and a drive gear 17 meshing with the driven gear 16.
Pulse motor 18 for controlling the turning angle on the lower end wall 10a of 0
Is transmitted to rotate the transducer 30 around the vertical axis through the frame 11.

In the hollow portion 13a of the cylindrical rotary shaft 13,
A rod-shaped rotary shaft 20 connected to the output shaft of a depression angle control pulse motor 19 fixed to the upper end wall 10b of the housing 10 is inserted. From the lower end of the hollow portion 13a to the frame 1
A drive bevel gear 21 is provided at the lower end of the rotary shaft 20 protruding into the inside 1. On the other hand, a semi-circular driven bevel gear 22 concentric with the horizontal shaft 12 is fixed to the rear surface 30b of the transducer 30. This driven bevel gear 2
2 meshes with the drive bevel gear 21, and the depression angle control motor 1
The rotating force of the rotating shaft 20 rotated by 9 in the turning direction is transmitted to the transducer 30 via the bevel gear trains 21 and 22 while being converted into the rotating force in the orthogonal depression direction. Accordingly, the transducer 30 has a horizontal axis 1
It is rotated around 2, and the depression angle of its transmitting / receiving surface 30a is controlled. Further, the input and output of the high frequency signal of the transducer 30 is performed by the slip ring 23 fixed to the peripheral surface of the rotary shaft 13 and the brush 2 slidably contacted with the slip ring 23.
4 through.

The entire space in which the housing 10 and the transducer 30 and the like below it are present is covered with a plastic dome (not shown) protruding from the bottom of the ship, and the lower part of the dome is made of oil or the like whose acoustic characteristics are similar to seawater. The medium is full. Between the inner peripheral surface of the shaft hole 14 of the housing 10 and the outer peripheral surface of the rotary shaft 13, and the hollow portion 13a of the rotary shaft 13.
Between the shaft and the outer peripheral surface of the rotary shaft 20, suitable shaft sealing devices 25 and 26, such as oil seals, are provided to prevent oil under the dome from rising through the gaps between the rotary shafts. is doing. A radial bearing 27 is interposed between the rotary shaft 13 and the rotary shaft 20.

As shown in FIG. 3, the pulse motor 18 for controlling the turning angle and the pulse motor 19 for controlling the depression angle are driven by
It is controlled by the number of input drive pulses P1 and P2, and as a result, the transmitting / receiving surface 3 of the transducer 30 is controlled.
The turning angle and depression angle of 0a are controlled. Here, when only the swing angle control motor 18 is rotated to control only the swing angle of the transducer 30, the transducer 30 swung by the rotary shaft 13 via the frame body 11 as well as the driven bevel gear 22 on the back surface 30b of the transducer 30. Also rotates as a unit, the meshing with the stationary drive bevel gear 21 changes. As a result, the transducer 30
The depression angle changes with the change of the turning angle. For this reason,
A part of the drive pulse P1 supplied to the turning angle control motor 18 is also supplied to the depression angle control motor 19 via a canceling circuit 31 including an N divider 32 and an adder 33.

That is, the canceling circuit 31 drives the drive bevel gear 21 by the same angle as the turning angle of the transducer 30.
Drive pulse P1 supplied to the swing angle control motor 18 is divided into 1 / N by the N divider 32, and the divided drive pulse signal .DELTA.P1 is depressed via the adder 33. Supply to the control motor 19. The frequency division ratio by the N frequency divider 32 depends on the gear ratio between the driven gear 16 of the rotary shaft 13 and the drive gear 17 of the output shaft 18a of the turning angle control motor 18 and the rotation angle per pulse of each pulse motor. Is set. As a result, the drive bevel gear 21 is rotated so as to cancel the change in the depression angle caused by the driven bevel gear 22 turning together with the transducer 30.
It is possible to control the turning of the transducer 30 while maintaining a constant depression angle. In addition, this control does not matter whether the transducer 30 is turned in any direction,
The same is done.

According to the above embodiment, the depression angle control motor 18
Is not attached to the frame 11, the inertial load that acts when the turning angle control motor 18 is driven becomes small.
Therefore, it is possible to speed up the turning angle control of the transducer 30 or downsize the turning angle control motor 18. Further, since it is not necessary to supply the drive current to the depression angle control motor 18 through the slip ring 23 and the brush 24 that is slidably contacted with the slip ring 23, the transducer that is input and output through the slip ring 23 and the brush 24. It is possible to prevent noise of the signal of 30.
Further, since the numbers of the slip rings 23 and the brushes 24 are reduced, the sliding torque is reduced and the volume of the dome covering the outside of the frame 11 can be reduced. Therefore, the turning angle control motor 18 is downsized and the slip ring 2 is
Combined with the decrease of 3, the miniaturization of the entire device is realized.
Further, since the depression angle control motor 18 does not exist in the dome, oil sealing by the shaft sealing devices 25 and 26 can be easily performed.

The rotary shaft 2 driven by the depression angle control motor 19
A power transmission mechanism including a driving bevel gear 21 and a driven bevel gear 22 for converting a turning force of 0 in the turning direction into a turning force of the transducer 30 in the depression direction is provided on the second rotating shaft 20 as shown in FIG. 4, for example. Pinion gear 2
1'and a power transmission mechanism formed by meshing of a crown gear 22 'fixed to the rear surface 30b of the transducer 30,
As shown in FIG. 5, a power transmission mechanism such as a worm gear including a worm 21 ″ provided on the second rotary shaft 20 and a worm wheel 22 ″ fixed to the rear surface 30b of the transducer 30 may be used.

The case where the sensor angle control device according to the present invention is applied to the sonar scanning mechanism has been described above as an example, but the azimuth and elevation angle control device of the antenna and light, smoke, odor, etc. are detected. It is obvious that the angle control device of the present invention can be applied to various angle control devices that control the angles around the two orthogonal axes for scanning and tracking of various sensors.

[0017]

Since the present invention is constructed as described above, the conventional drawback that one electric motor becomes the load of the other is eliminated, and high-speed control can be realized using a small electric motor of small power consumption. The effect is played. Furthermore, the rotating contact mechanism consisting of a slip ring and a brush does not require a power supply system to the electric motor, so the rotating contact mechanism is simple and the problem of noise mixing from the power supply system to the signal system is eliminated. Also, the effect that the reliability of the operation is improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment in which a sensor angle control device according to the present invention is applied to a sonar scanning mechanism.

2 is a side view of the embodiment of FIG. 1. FIG.

FIG. 3 is a conceptual diagram exemplifying a configuration of a canceling circuit that cancels a change in depression angle caused by control of a turning angle in the embodiments of FIGS.

FIG. 4 is a partial perspective view of another embodiment to which a pinion gear and a crown gear are applied as a power transmission mechanism in the present invention.

FIG. 5 is a partial perspective view of still another embodiment in which a worm and a worm wheel are applied as the power transmission mechanism in the present invention.

FIG. 6 is an explanatory diagram showing a scanning method for horizontally rotating an ultrasonic beam in fish finder.

FIG. 7 is an explanatory diagram showing a scanning method in which radiation of an ultrasonic beam is set in a depression angle direction and swirled in fish detection.

FIG. 8 is an explanatory diagram showing a scanning method in which an ultrasonic beam is changed only in the depression direction in fish finder.

FIG. 9 is a perspective view showing a conventional example of an angle control device for a transducer in a fish-finding sonar of a ship.

[Explanation of symbols]

 11 Frame 13 Cylindrical Rotating Shaft 18 Turning Angle Control Motor 19 Depression Angle Control Motor 20 Rotating Shaft 21 Drive Bevel Gear 21 'Pinion Gear 21 "Worm 22 Driven Bevel Gear 22' Crown Gear 22" Worm Wheel 30 Transducer (Sensor) 31 Offset Circuit

Claims (1)

[Claims] 1. A sensor angle control device for independently controlling the angles of two transducers, an antenna and other sensors around two orthogonal axes, wherein a frame for holding the sensor rotatably and a common axis are provided. First and second rotating shafts that have and extend independently of each other, and the frame body while converting the rotating force of the second rotating shaft into a rotating force in an orthogonal direction. A power transmission mechanism that transmits to the held sensor, and a first electric motor that controls an angle around one of the two orthogonal axes of the sensor by rotating the frame through the first rotation shaft. And a second electric motor that controls the angle around the other of the two orthogonal axes of the sensor via the power transmission mechanism by rotating the second rotation shaft, and supplies the second electric motor to the first electric motor. Part of the rotation command is the second
Of the two orthogonal axes by supplying the electric motor to the electric motor, the offset circuit for canceling the change in the angle around the other of the two orthogonal axes is provided. .