JPS5925976B2 - Variable angle ultrasonic probe drive circuit - Google Patents

Description

[Detailed description of the invention] The present invention relates to a variable angle ultrasonic probe drive circuit.

Conventionally, variable angle probes have been driven and rotation angle detected using combinations such as step motors and potentiometers, AC servo motors and synchro oscillators, DC motors and shaft encoders, torque motors and potentiometers, etc. In both cases, the disadvantage was that they were large. SUMMARY OF THE INVENTION An object of the present invention is to provide a small, lightweight, and simple variable-angle ultrasonic probe drive circuit that eliminates the above-mentioned drawbacks.

In the present invention, a comparison circuit is provided for the purpose of reciprocating the rotator of the variable angle probe, and a stroke setting switch is provided at one input terminal of the comparison circuit, and a scan center angle setting switch is provided at the other input terminal of the comparison circuit. The comparator circuit is configured so that the output of the comparison circuit is fed back to the stroke setting side.

Examples of the present invention will be described in detail below.

FIG. 1 is a diagram schematically showing a variable angle ultrasonic probe driven by a drive circuit of the present invention. 1 is a fixed shoe, 2 is a rotating element, 3 is a vibrator, and the rotating element can be rotated in the direction of arrow 4.

Now, when the ultrasonic beam 5 is rotated in the range θs around the angle θc, the ultrasonic beam 5 is scanned in a fan shape in the range shown by the dotted line. Note that 6 is the subject. Table 1 shows the relationship between the scanning center angle θc and the scanning stroke angle θs.

A circuit suitable for setting and driving this table is shown in FIG. In FIG. 2, 10 is a comparison circuit, and 11 is a switching circuit.

12 is a stroke setting switch, 13 is a scanning center angle setting switch, 14 is a switching transistor, 15 is a switching relay coil, 16 is a protection diode, 1?
18 is a relay contact, 18 is a manual polarity changer, 19 is a speed control resistor, 20 is a manual inch fender switch, 21 is a motor, 22 is connected to the rotating shaft of the motor via a gear, and This is a potentiometer for detecting rotation angle.

23 is a scanning center angle/setting resistor, 24 is a stroke setting resistor, 25 is a power source for the potentiometer 22 and the scanning center angle setting resistor 23, and 26 is a motor power source.

The changeover switch 13 in Table 1 has contacts C-1 to C-7.
Table A6. It corresponds to l~7, and the contact C-1 is θc=
At 45A, the contact point C-7 is θc-45.

The changeover switch 12 has contacts S-1 to S-4 for setting θs-±1 gear, and contact S-4 for setting θs-±60-. Next, the operation of this circuit will be explained step by step.

Step 1 If the contact point A of the potentiometer 22 is located to the right of the position shown in the figure (center) when facing the page, the following table (Table 2) will be applied. S. As shown in l, EA>EB, b, relay contact 1
7 becomes a, the motor 21 rotates to the left and moves the contact point A toward the center.

Step 2 Even if contact A of potentiometer 22 is at the center position, EA
Since the relationship >EB remains unchanged, the motor 21 further rotates to the left and moves the contact point A further to the left.

Step 3 When the contact A of the potentiometer 22 reaches a predetermined position on the left side, EA>EB, the collector voltage Ec of the V1 transistor 14 becomes zero voltage, the relay contact 17 becomes B, and the motor 21 rotates in the right direction. , contact A of potentiometer 22 moves toward the center.

Step 4 Even if contact A of potentiometer 22 reaches the center position, E
Since the relationship A>EB remains unchanged, the motor 21 rotates to the right, and the contact A of the potentiometer 22 further moves to the right.

Step 5 When the contact A of the potentiometer 22 reaches a predetermined position on the right side, EA>EB, and the motor 21 rotates to the left as in step 1, moving the contact A toward the center.

Step 6 When contact A of potentiometer 22 comes to the center position, E
When A>EB, the motor 21 rotates to the left as in step 2, and the contact A moves to the left.

That is, contact AlliC-1 or potentiometer 2
2 round trip.

Therefore, it is possible to set the central angle of scanning. Further, the scanning width of the reciprocating scan is equal to the voltage EB of S-1, and the lower the voltage of S-1, the smaller the scanning range, and the higher the voltage of S-1, the larger the scanning range.

Therefore, the scanning range can be determined by selecting the contacts S-1, S-2, S-3, . . . . Now, when the switch 13 is at the contact point C-1 and the switch 12 is at the contact point S-1, it means that the rotor 2 reciprocates with θc=-45 off and θs. An example of this operation is shown in FIG. That is, the horizontal axis in FIG. 3 is the scanning center angle θc, and the vertical axis is the comparison circuit 1.
The output EO is 0. The output EO corresponds to the direction of rotation of the rotor 2. E at -300. If becomes positive, the motor moves the contact of the potentiometer to the negative side, and when it becomes -6♂, EO becomes negative, the motor moves the contact of the potentiometer to the positive side, and at -30, EO becomes negative. . When D is -positive, the motor moves the potentiometer contact to the negative side and continues drawing the 31 loop. In this way, the loop 32 continues to be drawn for the combination of C-2 and S-2, the loop 33 for the combination of C-3 and S-3, and the loop 34 for the combination of C-4 and S-4. Although the present invention has made it possible to automatically drive a variable angle ultrasonic probe with a simple configuration consisting of one comparison circuit and one switching circuit, it is possible to automatically drive a variable angle ultrasonic probe using a simple configuration including one comparison circuit and one switching circuit. shall be included in the present invention even if it is used.

Furthermore, although an example of a motor is shown as a driving method, it can also be realized by an electronic circuit method. As a circuit for driving a variable angle ultrasonic probe, we provided a circuit consisting of a comparison circuit and a switching circuit.

This circuit is small, lightweight, and has a small number of parts, making it highly reliable, and has great effects such as being able to keep the angular speed of the rotor constant.

[Brief explanation of drawings]

Fig. 1 shows an overview of the variable angle ultrasonic probe. Fig. 2 is a diagram of the ultrasonic probe 1 drive circuit α of the present invention, and Fig. 3 is an example of the ultrasonic probe 1 drive circuit of the present invention. FIG. 10... Comparison circuit, 11... Switching circuit, 1
2... Stroke setting switch, 13... Scan center angle setting switch.

Claims (1)

[Claims] 1 Stroke setting switch for variable angle ultrasonic probe,
A scanning center angle setting switch for a variable angle ultrasonic probe, the output of the stroke setting switch is input to one input terminal, and the output of the scan center angle setting switch is input to the other input terminal. , a comparison circuit that generates an output depending on the magnitude relationship thereof, and means for feeding back the output of the comparison circuit to change the setting value of the stroke setting switch.