JPS6033922Y2 - Automatic body thickness measuring device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an apparatus for automatically measuring the thickness of a human body.

For example, in X-ray imaging equipment, the transmittance of X-rays varies depending on the body thickness of the human body (hereinafter referred to as the patient), which is the subject, so the body thickness is measured in advance and the X-ray radiant energy and dose values are adjusted accordingly. In order to take accurate pictures, the camera was able to take accurate pictures by changing the

In this case, conventional body thickness measurement involves the operator applying a caliper-like chest meter directly to the patient and measuring visually, which takes a long time to measure and also causes discomfort and pain to the patient. There was a problem of giving.

The present invention was developed to solve the above problem, and uses ultrasound to automate the measurement and enable high-speed measurement, as well as non-contact measurement, eliminating discomfort and pain for the patient. The object of the present invention is to provide an automatic body thickness measuring device.

The present invention will be specifically explained below using examples.

FIG. 1 is a schematic diagram for explaining the principle of the device of the present invention.

This device is composed of an ultrasonic device 1 including an ultrasonic oscillator IA and its receiver IB, and a control circuit 2 for controlling the ultrasonic device 1. Body thickness is measured by operating the ultrasound device 1.

That is, before positioning the human body 4 on the back plate 3, ultrasonic waves are emitted toward the back plate 3, and the time for the echoes (reflected waves) to return is determined. 3, and then, with the human body 4 positioned on the back plate 3, ultrasonic waves are emitted again toward the measurement position of the human body 4, and the return time of the echo is determined. 1 and the surface of the human body 4, and finally calculate the difference (L-Lm) between the two to obtain the body thickness ΔL.

FIG. 2 is an explanatory diagram showing an embodiment in which the device is installed in an X-ray imaging device.

This X-ray imaging device includes a rectangular fixed pedestal 5 and a rectangular fixed pedestal 5.
A rotating pedestal 6 rotatably supported approximately at the center of the pedestal, a bed device 7 fixed to the lower part of the rotating pedestal 6 that can be raised and lowered, and placed on a top plate 7A provided on the bed device 7. The X-ray tube 8 and the imaging device 9 are arranged oppositely above and below the patient 4.

Note that 10 is a diaphragm device.

The ultrasonic device 1 is attached to the side of the diaphragm device 10 of such an X-ray imaging device, and the control circuit 2 is installed at a suitable external location, and both are connected by a cable 2a.

Here, one embodiment of a specific configuration of the control circuit 2 will be described with reference to FIG.

11 is an oscillation control circuit that controls the oscillation interval of the ultrasonic oscillator IA, 12 is a sine wave generation circuit that generates a sine wave corresponding to the oscillator 1A in synchronization with the output of the oscillation control circuit 11, and 13 is the sine wave generator. A drive circuit that receives waves and drives the oscillator 1A, 14 is a simulated signal forming circuit, and is constituted by a timer that sets a time obtained based on the distance between the ultrasonic device 1 and the top plate 7A. (This time setting is done, for example, by means of a time calibration during installation of the device).

15 is a measurement start signal generation circuit that outputs a pulse-like signal in synchronization with the start of operation of the simulated signal forming circuit 14;
6 is the point in time when the output of the simulated signal forming circuit 14 stops (
In other words, this is a top plate simulated echo signal generation circuit that generates a trigger pulse at the time the timer expires.

17 is an amplification circuit that amplifies the echo signal from the patient received by the ultrasound receiver IB, 18 is a level matching circuit, and 19 is a patient echo signal latch circuit. For example, when the echo from patient 4 is received, It consists of a timer that starts operating from

20 is a distance display clock generation circuit that generates clocks at predetermined intervals, and 21 is a temperature compensation circuit for stably operating the clock generation circuit 20 against temperature changes in the speed of sound.

22 is an AND gate circuit which operates both the outputs of the patient echo signal latch circuit 19 and the clock generation circuit 20 by two people;
23 is a W counter that is controlled by the output of the measurement start signal generation circuit 15 and counts the output clock of the AND gate circuit 22; 24 is a W counter that is controlled by the output of the measurement start signal generation circuit 15; The latch circuit 25 is an LED display circuit driven by the output of the latch circuit 23 to display distance.

Reference numeral 26 denotes an interference blanking circuit which is operated by the output of the measurement start signal generation circuit 15, and uses its operation signal to prevent the patient echo signal latch circuit 19 from malfunctioning due to interference of sound waves during oscillation.

Next, the operation of such an automatic body thickness measuring device will be explained with reference to the timing chart of FIG. 4.

First, the patient 4 is placed on the top plate 7A and positioned so that the X-ray tube 8 and the imaging device 9 are placed opposite each other at a position (for example, the chest) where the patient's waist should be imaged.

Then, press a body thickness measurement start button (not shown).

At this time, a signal V11 at a predetermined interval is sent from the oscillation control circuit 11.
is generated, and in synchronization with this, a sine wave signal V□3 is generated from the drive circuit 13 to drive the ultrasonic oscillator IA.

Simultaneously with the generation of the output from the oscillation control circuit 11, the timer 14 of the simulated signal forming circuit operates, and furthermore, the measurement start signal generating circuit 15 outputs the pulse signal 15.

At this time, an interference wave is received by the receiver IB during the oscillation operation of the ultrasound oscillator IA, but at the same time, the interference blanking circuit 26 operates and generates the blanking signal V213, so the patient echo signal latch circuit The output ■1° of No. 19 maintains its initial state (low level).

Since the latch circuit 19 is at a low level, the AND
The output V22 of the gate of the gate circuit 22 is at a low level, and no clock is supplied to the counter 23.

Therefore, no counting operation is performed, and the display circuit 25 also does not operate (time t2).

Next, the ultrasonic waves emitted toward the patient 4 hit the body surface of the patient 4 and are received by the receiver 1B as an echo signal.

The received echo signal is applied to a patient echo signal latch circuit 19 via an amplifier circuit 17 and a level matching circuit 18.

In the latch circuit 19, a timer operates in synchronization with the rise of the output (18) of the level matching circuit 18, and a signal (2)9 which remains at a high level for a predetermined period of time is generated.

Then, based on the operation of the latch circuit 19, the gate of the AND gate circuit 22 is opened, and the clock signal from the clock generation circuit 20 is outputted and applied to the counter 23 (output V2□).

Therefore, the counter 23 starts counting and sends the count output to the latch circuit 24 (poetry L).

At this stage, when the timer of the simulated signal forming circuit 14 expires, a trigger pulse V16 is outputted from the top simulated echo signal generating circuit 16 in synchronization with this.

The latch circuit 24 is activated by the trigger pulse V16, and the output of the counter 23 at this point in time is latched.

The LED display circuit operates based on the latch output of the latch circuit 24, and the distance is displayed (time 14).

The distance displayed in this manner becomes the body thickness ΔL.

Finally, when the next oscillation control signal V11 is output and the measurement start signal □5 is output, the patient echo signal latch circuit 19, counter 23, latch circuit 24, display circuit 2
5 is cleared and returns to the initial state to prepare for the next measurement (time t5).

According to the apparatus described in detail above, the body thickness can be automatically measured by emitting ultrasonic waves and processing the echo signals from the tabletop and the patient's body surface, thereby increasing the speed.

At this time, since the instrument is not brought into contact with the patient's body surface, the patient will not feel discomfort or pain.

In the above embodiment, instead of measuring the distance between the top plate and the ultrasonic device at each measurement time, the distance between the top plate and the ultrasonic device is measured only once when the device is installed, and the result is stored in the simulated signal forming circuit. Since the body thickness is measured based on the measured height, the speed can be further increased.

Furthermore, the present invention can eliminate the influence of ultrasonic oscillation time on the receiving circuit side by providing the interference blanking circuit 26 on the ultrasonic receiving circuit side.

Further, the device has the advantage that it is small, inexpensive, lightweight, and easy to install.

It should be noted that the present invention is not limited to the above-mentioned embodiments; for example, in the above-mentioned embodiments, the ultrasonic device is described as having an oscillator and a receiver as separate units, but it is also possible to use a device that can perform transmission and reception with a single element. You may.

Furthermore, the specific configuration of the control circuit that controls the ultrasonic device is not limited to the embodiment described above.

Furthermore, the present invention is not limited to being applied to an X-ray imaging apparatus as in the embodiment described above, but can also be used alone.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram for explaining the principle of the inventive device, Fig. 2 is an explanatory diagram showing an embodiment of the inventive device applied to an X-ray imaging device, and Fig. 3 is a schematic diagram for explaining the principle of the inventive device. FIG. 4 is a block diagram showing an example of a specific configuration of the control circuit used, and a timing chart for explaining the operation. 1... Ultrasonic device, IA... Oscillator,
1B...Receiver, 2...Control circuit, 1
1...Oscillation control circuit, 12...Sine wave generation circuit, 13...Drive circuit, 14...
- Simulation signal forming circuit, 15... Measurement start signal generation circuit, 16... Top plate simulated echo signal generation circuit, 17... Amplification circuit, 18...・Level matching circuit, 19...Patient echo signal latch circuit, 20...Clock generation circuit, 21...
...Temperature compensation circuit, 22...-AND gate circuit, 23...Counter, 24...Latch circuit, 25...Display circuit, 26...・・・・・・
・Blanking circuit.

Claims (2)

[Scope of utility model registration request] (1) In a device for measuring the body thickness of a human body standing upright along a back plate, an oscillation circuit that generates an ultrasonic driving pulse;
an ultrasonic oscillator disposed at a predetermined distance from the back plate, which transmits ultrasonic waves toward a human body standing upright along the back plate using drive pulses supplied from the oscillation circuit; an ultrasonic device having a receiver for receiving ultrasonic echoes, a receiving circuit for generating detection pulses by the ultrasonic echoes, and an oscillation circuit configured to not generate detection pulses while the oscillation circuit generates drive pulses. an interference blanking circuit that controls the receiving circuit; and a simulation that generates a simulated pulse after the oscillation circuit generates a driving pulse, with a delay corresponding to the time that the ultrasonic waves travel back and forth between the ultrasonic device and the back plate; An automatic body thickness measuring device comprising: a signal forming circuit; and a control circuit that measures a time difference between the detected pulse and the simulated pulse. (2) The control circuit includes a counter that starts counting based on the detection pulse, a latch circuit that latches the output of the counter using the simulated pulse of the simulated circuit, and a display that converts the latch output into a length and displays it. An automatic body thickness measuring device according to claim 1 of the utility model registration claim, comprising: a circuit;