JPH0298663A - Method for measuring and detecting tree and its device - Google Patents

Abstract

PURPOSE:To miniaturize the device and to prevent the damage of a tree by measurement by forming the front end of wave transmitting and receiving ends to a sharpened horn shape, piercing the front end of the wave transmitting and receiving ends into the woody part from the outside of the bark of the tree and transmitting and receiving waves to and from the tree. CONSTITUTION:The fine end face 12b of end part 12 of wave transmitting and receiving part 10 is sharpened to about 2 to 3mm diameter and is formed to the horn shape. The fine end face 12b is pierced from the outside of the bark 1a into the woody part and is mounted thereto. A wave transmission signal is applied to the oscillator 11a of the wave transmitting part 10a which converts this signal to an ultrasonic wave signal and transmits the signal from the end face 12b into the woody part 1b of the tree 1. The signal is received in the wave receiving part 10b which is similarly mounted by piercing this part into the woody part 1b from the outside of the tree 1. The attenuation of the ultrasonic waves by the intervention of the bark 1a is obviated in this way and the flawing of the tree by removing the bark 1a is obviated, in addition the transmission loss of the ultrasonic waves is lessened and, therefore, the transmission signal can be produced with the smaller output and the device is miniaturized.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides 1.11 a method for measuring and detecting the internal state and thickness of a tree using phenomena such as transmission or reflection of ultrasonic waves, and an apparatus using the method. Regarding.

[Conventional technology]

When thinning trees in a mountain forest, it is better to leave as many good trees with good growth as possible, and select defective trees for thinning.

However, this defect may be visible from the outside or may not be visible from the outside, such as when there is internal decay or a cavity.

In order to sort out defective trees that cannot be seen by their appearance, it has been proposed to detect them using phenomena such as transmission or reflection of ultrasonic waves.

In addition, in order to examine the growth rings of trees without cutting them down, a method of detecting trees using a similar phenomenon has been proposed.

In the former case, a specific conventional method is to place the ultrasonic transducer 2 on the transmitting side at one position outside the tree 1, as shown in FIG. Route 1
01 a ・I 01 b −10 In is selected at the position of the opposing point, and the ultrasonic transducer 3 on the receiving side is placed for measurement.

This measurement is performed by comparing the signal given from the wave transducer 2 on the transmitting side and the signal obtained from the transducer 3 on the receiving side.
For example, route 101. In c, the ultrasonic wave is attenuated due to the fishing part 102 on the way, so the fishing part 102
(1) The presence of the fishing part 102 on this route can be detected because the signal obtained by the ultrasonic transducer 7 on the delivery side is considerably smaller or completely absent compared to other routes. .

[Problem to be solved by the invention]

However, the above method is hampered by the presence of the bark 1a, and cannot be measured unless a considerably high-output ultrasonic signal is applied to the ultrasonic transducer 2 on the transmitting side, which requires a large device and power source. It requires a lot of effort and cannot be put to practical use in areas such as mountains and forests.

For this reason, as shown in Fig. 4, a part of the bark 1a is removed to expose the surface of the wood 1b, and the transmitting and receiving surfaces of the ultrasonic transducers 2 and 3 are applied to this surface for measurement. It seems common sense to take this approach.

However, with this method, bark 1a is removed without distinguishing between good and bad trees, which has the disadvantage that even previously good trees become bad trees due to the damage caused by this removal. .

Therefore, there is a problem in that it is expected to provide a measurement detection method that does not have these disadvantages and a device embodying the method.

[Means to solve the problem]

In order to transmit and receive ultrasonic waves, this invention uses a method in which the transmitting and receiving ends are formed into a horn shape with a pointed tip, and the tips are pierced into the wood from outside the bark to transmit and receive waves. The above-mentioned problem can be solved, and furthermore, as an embodiment of this method, a device for transmitting and receiving waves using a horn-equipped vibrator with a sharpened horn tip is provided. This is what I did.

〔Example〕

Examples will be described below with reference to the drawings.

Fig. 3 (A) shows the configuration of the wave transmitting/receiving part IO, which is a type in which a transducer part 11 for transmitting and receiving ultrasonic waves and a wave transmitting/receiving end part 12 for transmitting and receiving waves to trees are assembled into one piece. This is a vibrator with a horn.

The vibrator portion 11 is obtained by bonding the wave transmitting/receiving surface lle of the vibrator 11a to the thick end surface 12a of the wave transmitting/receiving end portion 12 by adhesive or the like, and attaching a cable lie to connect the electric terminal 11bl of the piezoelectric vibrator 11a.

For example, a bolted Langevin type ceramic electrostrictive vibrator is used as the vibrator 11a, and an insulating stud l1g is attached using the screw hole for the tightening bolt so as to cover the other surfaces except the wave transmitting/receiving surface 11e. cover li
d is held by an insulating stud 11g, and a cable llc leading to an electric terminal 11b is pulled out via a connector Iff provided on the cover lid.

The transmitting/receiving end portion 12 is a horn that transmits the transmitting/receiving energy of the vibrator 11a between the wide end surface 12a and the narrow end surface 12b, and the narrow end surface +2b side is sharpened to a shape that makes it easy to penetrate into the wood of a tree.

The pawn is, for example, an exponenial type solid horn in which the side surface of a cone is formed into a so-called expohonsial shape, and the diameter of the narrow end surface 12b is 2 to 3IllI1.
It has a conical shape with a pointed tip.
It is formed using a steel material and hardened by nitriding or the like.

No. 3m (E> indicates the installation state of the transmitting/receiving 1f IL part 10 for detecting the condition inside the tree, and the transmitting part 10a.
Both the wave receiving part 10b and the wave transmitting/receiving part 10 in FIG. 3(A)
Attach the horn by sticking the pointed part of the narrow end surface 12b into the tree IC from the outside of the bark ib.

Figure 1 shows the configuration for measuring and detecting the internal state of trees.
The wave transmitting part 10a and the wave receiving part 10b are attached in the state shown in FIG. 3(B).

The measurement part 20 includes a transmission signal generation part 20a and an observation part 20.
It is composed of b.

The transmission signal generation portion 20a generates the transmission signal S in FIG. 2(A).
This is a pulse transmitter that generates a signal f of the vibration frequency of the vibrator 11a with a predetermined narrow pulse width TI and repeated at a predetermined period T2 as shown in FIG.

For example, the signal f is 75 kHz and the pulse width TI is 100
ps, and the period T2 is 50 m5.

This part is composed of a trigger pulse generation circuit 201a that generates a pulse signal S3 with a period T2, and a pulse wave transmission circuit 201b that is triggered by this pulse signal S3 and generates a transmission signal S1, and its output The signal, that is, the transmission signal Sl is applied to the transducer 11a of the transmission part 10a, converted into an ultrasonic signal, and the thin end surface 12b of the horn also transmits the wave into the tree part 1b of the tree l.

The ultrasonic signal propagates within the xylem, is received by the receiving part molecule ob, and is converted into an electrical signal by the vibrator 113 to obtain the delivery signal S2.

The observation section 20b is a cathode ray tube measuring instrument that measures the magnitude and delay time of the received signal S2.

Then, this part receives a part of the pulse signal S3 of the trigger pulse generation circuit 201a from the transmission signal generation part 20a, and as shown in FIG. In order to synchronize the sweep signal 201d, the pulse signal S3 is converted into a no-driger signal to synchronize it, and the pulse signal S3 is added to the amplitude image 2 on the sweep time axis 201d.
01e and display. Further, the received signal S2 is amplified to a predetermined signal strength by the amplifier circuit 202a, and this signal is displayed as an amplitude image 201f on the sweep time axis 201c.

The delay time on the sweep line from the amplitude image 201e to the starting point of the amplitude image 201f (that is, the distance is proportional to the width of the tree 1, so the thickness can be measured, and the amplitude of the amplitude image 201f is When there is no damage to the internal state of the tree, the ultrasound appears with a large amplitude, but when there is a defect inside the tree, such as a brim or cavity, the ultrasound is attenuated by the defect, so the amplitude is small or no image appears. This makes it possible to detect the internal state of the tree.

The transmission signal generating portion 20a can be configured by, for example, a pulse transmission circuit used in a well-known fish finder, etc., with a shortened pulse width and repetition period. The measuring section 20b can be configured using, for example, a portable synchronized oscilloscope.

[Transformation implemented]

This invention can be implemented in the following modified manner.

(1) The horn portion of the wave transmitting/receiving end portion I2 is made into another horn shape such as a conical horn or a stepped horn.

(2) The transmission signal 31 is made into a high-pressure discharge pulse, and the vibrator 1
1a is forcibly vibrated and the ultrasonic pulse signal to be transmitted is made into a naturally attenuated pulse, thereby making the configuration simpler and consuming less power.

(3) A/D convert the signal obtained by detecting and rectifying the delivery signal S2, converting it into a digital value, and providing a keyboard for inputting the tree number of tree 1. This digital value is printed and recorded on the printer along with the tree number, and the thinning survey is carried out. Enable document creation automatically.

(4) The delay time t of the delivery signal S2 with respect to the pulse signal S3 is counted using a clock pulse for time measurement, converted into a digital value, and this digital value is printed together with the tree number on the printer described in (3) above.

(5) The vibrator 11a is configured as a 7-elite magnetostrictive vibrator or a single ceramic electrostrictive vibrator. Also,
The cover lid part is molded with urethane rubber. Furthermore, put the cable llc out to the side,
The back of the wave transmitting/receiving part is struck with a rubber hammer or the like to make it easier for the tip of the horn to reach the wood part 1b even if the bark 1a is thick and hard.

(6) The transmitting signal generating section 20a is configured integrally with the transmitting section 1ira to reduce the number of constituent elements.

(7) Instead of the pulse signal S3 given to the cathode ray tube display, the transmitted wave signal S1 is given and displayed in the same way, so that the normality of the transmitted wave signal Sl can be monitored at the same time.

(8) The transmitting/receiving end portion 12 is made of another metal. For example, the horn should be made of stainless steel, and the sharpened tip of the horn should be hardened by bluing to prevent rust or corrosion caused by dew drops or tree sap.

〔Effect of the invention〕

According to the present invention, as described above, the wave transmitting/receiving end portion 12 is made into a horn, and the tip thereof is pierced into the wood from the outside of the bark to transmit and receive ultrasonic waves. There is no attenuation of ultrasonic waves due to interference, there is no need to remove or damage even good trees, and the ultrasonic waves are focused by the horn, and the tip of the horn bites into the xylem, so the ultrasonic waves are not attenuated. Because of the low transmission loss,
The transmitting signal can be made small in output, for example, the pulse itself can be
Since measurement and detection can be performed sufficiently with an output of about QW, the device has the advantage of being small and convenient and can be provided at low cost.

[Brief explanation of the drawing]

The drawings show an example. Fig. 1 is a configuration diagram during measurement detection work, Fig. 2 (A) is a signal waveform diagram, Fig. 2 (B) is a display image diagram, and Fig. 3 (A) is a wave transmission/reception diagram. Partial cross-sectional side view of part, 3rd
Figure (B) is a cross-sectional plan view of the installed state of the transmitting and receiving parts, and Figure 4.
FIG. 5 is a cross-sectional plan view of a conventional wave transmitting and receiving portion attached. 1...Trees 2...Ultrasonic transducer on the transmitting side 3...Ultrasonic transducer IO on the receiving side...Transmitting/receiving part 20...Measuring part Patent Applicant: Kohden Co., Ltd. Manufacturing site transmission signal generation measurement Fig. 1 Fig. 2 (A) Fig. 4//e Fig. 38! ! 1(A) Tekiuriji [11 shosho (flag)

Claims (1)

[Scope of Claims] 1. A method for measuring and detecting the internal condition and thickness of a tree using phenomena such as transmission or reflection of ultrasonic waves, comprising: a. transmitting the ultrasonic waves into the tree; or, in order to receive the ultrasonic waves in the tree, the transmitting/receiving end is formed into a horn shape with a sharp tip; b. the tip is pierced into the xylem from outside the bark of the tree, and Or a tree measurement detection method characterized by receiving waves. 2. An apparatus for detecting defective trees such as rotten trees and hollow trees using the method according to claim 1, wherein: a. The transmitting and receiving ends are formed by sharpening the tip of the horn of a vibrator with a horn. (a) a vibrator tip forming means for forming a transducer; b. one of the transmitting and receiving ends of the two horn-equipped vibrators is pierced into the tree at a different position from the other; c. transmitting/receiving end opposing means for arranging the transmitting/receiving ends of the transmitting/receiving ends; A tree internal condition detection device comprising: a detection means for detecting the defective tree by measuring a difference in magnitude of received signals. 3. An apparatus for detecting the internal state and thickness of a tree using the method according to claim 1, wherein: a) the transmitting and receiving ends are formed by sharpening the tip of the horn of a vibrator with a horn; vibrator tip forming means; b. one of the transmitting and receiving ends of the two horned vibrators is inserted into the tree at a different position from the other; sending/receiving end facing means for arranging the sending/receiving ends; c. transmitting an ultrasonic pulse signal by giving an ultrasonic pulse signal output to one of the two horn-equipped vibrators; d. generating the ultrasonic pulse signal using a pulse signal having a predetermined period as a trigger signal, and determining the time between the pulse in the trigger signal and the corresponding pulse in the received signal; Tree measurement/detection characterized by comprising a measurement/detection means that measures the thickness by measuring the interval and detects the internal state by measuring the amplitude of the pulse in the received signal. Device.