CN212963503U - Ultrasonic sensor - Google Patents
Ultrasonic sensor Download PDFInfo
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- CN212963503U CN212963503U CN201922380764.9U CN201922380764U CN212963503U CN 212963503 U CN212963503 U CN 212963503U CN 201922380764 U CN201922380764 U CN 201922380764U CN 212963503 U CN212963503 U CN 212963503U
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Abstract
The utility model discloses an ultrasonic sensor, which comprises a rubber sleeve, a sound wedge, a piezoelectric crystal chip and a stainless steel cap, wherein the stainless steel cap is arranged in the rubber sleeve, the sound wedge is embedded at the top end of the rubber sleeve, the piezoelectric crystal chip is arranged in the stainless steel cap, and a lead is respectively welded on the piezoelectric crystal chip and the stainless steel cap; the piezoelectric crystal chip is uniformly provided with a plurality of transverse dividing grooves and radial dividing grooves, and the piezoelectric crystal chip is uniformly divided into a plurality of square vibrators by the transverse dividing grooves and the radial dividing grooves. Has the following advantages: the piezoelectric crystal chip is divided into small vibrators to realize multipoint resonance, so that the bandwidth is increased, the multipoint resonance is facilitated, the vibration starting speed is increased, and the consistency of central frequency is facilitated.
Description
Technical Field
The utility model relates to a sensor, specific theory relates to an ultrasonic wave air sensor, belongs to sensor technical field.
Background
The sensor is a detection device which can sense the measured information and convert the sensed information into an electric signal or other information in a required form according to a certain rule to output so as to meet the requirements of information transmission, processing, storage, display, recording, control and the like. There are many kinds of sensors, for example, ultrasonic air sensors are widely used at present, and are mainly used in industry, national defense, biomedicine, etc., and an ultrasonic air sensor is a sensor that converts an ultrasonic signal into another energy signal (usually, an electrical signal).
As shown in fig. 1, a piezoelectric crystal ceramic chip of a conventional sensor is uniformly provided with a plurality of strip-shaped dividing grooves, the grooves penetrate through two ends of the ceramic chip, all the dividing grooves are arranged in the same direction, and the dividing grooves uniformly divide the piezoelectric crystal ceramic chip of the conventional sensor into a plurality of strip-shaped plate vibrators with bottoms connected together.
The sensor made of the existing piezoelectric crystal ceramic chip has narrow bandwidth, unstable receiving sensitivity and insufficient compatibility of the change of the drift impedance of frequencies at different temperatures.
Disclosure of Invention
The to-be-solved technical problem of the utility model is not enough more than to, the utility model provides an ultrasonic sensor, realize multiple spot resonance after the little oscillator is cut apart into to the piezoelectric crystal chip, be favorable to the increase of bandwidth, be favorable to multiple spot resonance, be favorable to the oscillation starting speed to increase, be favorable to central frequency's uniformity, the stability of receiving sensitivity, can adapt to the measurement requirement of various different air main control units, the increase of bandwidth is favorable to the compatibility of the change of the drift impedance of frequency under different temperatures, the stability and the uniformity of sensor have been improved greatly.
For solving the technical problem, the utility model discloses a following technical scheme:
an ultrasonic sensor comprises a rubber sleeve, a sound wedge, a piezoelectric crystal chip and a stainless steel cap, wherein the stainless steel cap is installed in the rubber sleeve, the sound wedge is embedded into the top end of the rubber sleeve, the piezoelectric crystal chip is arranged in the stainless steel cap, and a lead is welded on the piezoelectric crystal chip and the stainless steel cap respectively;
the piezoelectric crystal chip is uniformly provided with a plurality of transverse dividing grooves and radial dividing grooves, and the piezoelectric crystal chip is uniformly divided into a plurality of square vibrators by the transverse dividing grooves and the radial dividing grooves.
Furthermore, the transverse dividing groove and the radial dividing groove are both long strips penetrating through two ends of the piezoelectric crystal chip.
Further, the transverse dividing grooves and the radial dividing grooves are perpendicularly arranged in a crossed mode.
Furthermore, the upper part of the square oscillator is separated by a transverse dividing groove and a radial dividing groove, and the bottoms of the square oscillators are connected together.
Further, the length of the transverse dividing groove is the same as that of the piezoelectric crystal chip, and the length of the radial dividing groove is the same as that of the piezoelectric crystal chip.
Further, the widths of the transverse dividing groove and the radial dividing groove are 0.23mm to 0.27 mm.
Further, the depth of the transverse dividing groove and the radial dividing groove is 2.3-2.4 mm.
Further, circular through-hole has been seted up at the top of rubber sleeve, and the lower part of rubber sleeve is equipped with the annular groove, and in the annular groove was embedded into to the flange of stainless steel cap lower extreme, the upper surface on stainless steel cap top and the lower surface laminating on rubber sleeve top, the sound wedge embedding was in circular through-hole, and the upper surface on stainless steel cap top is pasted to the bottom of sound wedge, and the top of piezocrystal chip is fixed on the lower surface on stainless steel cap top.
Furthermore, the length and the width of the piezoelectric crystal chip are 7.5mm multiplied by 7.5mm, the number of the transverse dividing grooves and the number of the radial dividing grooves are 3, and the transverse dividing grooves and the radial dividing grooves divide 16 square oscillators with the same size on the piezoelectric crystal chip.
Furthermore, the length and the width of the piezoelectric crystal chip are 8.25mm multiplied by 8.25mm, the number of the transverse dividing grooves and the number of the radial dividing grooves are 4, and 25 square vibrators with the same size are divided by the transverse dividing grooves and the radial dividing grooves on the piezoelectric crystal chip.
The utility model adopts the above technical scheme, compare with prior art, have following technological effect:
the piezoelectric crystal chip is beneficial to increasing the bandwidth after being divided into small vibrators, is beneficial to multipoint resonance, is beneficial to increasing the oscillation starting speed, is beneficial to the consistency of central frequency and the stability of receiving sensitivity, can adapt to the measurement requirements of various air main control units, is beneficial to the compatibility of the change of drift impedance of the frequency at different temperatures, and greatly improves the stability and the consistency of the sensor.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the technical solutions in the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.
FIG. 1 is a schematic structural diagram of a piezoelectric crystal chip in the prior art;
fig. 2 is a schematic structural diagram of a sensor in embodiment 1 and embodiment 2 of the present invention;
fig. 3 and 4 are schematic structural views of a piezoelectric transistor chip according to embodiment 1 of the present invention;
fig. 5 is a schematic structural diagram of a piezoelectric transistor chip according to embodiment 2 of the present invention;
FIG. 6 is a graph of time difference of zero flow with temperature variation for a piezoelectric crystal chip in the prior art;
FIG. 7 is a graph of frequency and impedance curves for a prior art piezoelectric crystal chip;
FIG. 8 is a waveform diagram of an oscilloscope experiment of a piezoelectric crystal chip in the background art;
fig. 9 is a time difference graph of zero flow with temperature variation of the piezoelectric transistor chip according to embodiment 1 of the present invention;
FIG. 10 is a graph showing the frequency and impedance of a piezoelectric transistor chip according to embodiment 1 of the present invention;
fig. 11 is a waveform diagram of an oscilloscope experiment of a piezoelectric transistor chip according to embodiment 1 of the present invention;
fig. 12 is a graph showing the frequency and impedance of the piezoelectric transistor chip according to embodiment 2 of the present invention;
fig. 13 is a waveform diagram of an oscilloscope experiment of a piezoelectric transistor chip according to embodiment 2 of the present invention;
in the figure: the piezoelectric resonator comprises a stainless steel cap 1, a piezoelectric crystal chip 2, a sound wedge 3, a rubber sleeve 4, a lead 5, a transverse dividing groove 21, a radial dividing groove 22 and a square oscillator 23.
Detailed Description
Embodiment 1, as shown in fig. 2 to 4, an ultrasonic sensor, including rubber sleeve 4, acoustic wedge 3, piezoelectric crystal chip 2 and stainless steel cap 1, circular through-hole 41 has been seted up at the top of rubber sleeve 4, the lower part of rubber sleeve 4 is equipped with annular groove 42, stainless steel cap 1 is installed in rubber sleeve 4, the continuation limit of stainless steel cap 1 lower extreme is embedded into annular groove 42, the upper surface on stainless steel cap 1 top is laminated with the lower surface on rubber sleeve 4 top, acoustic wedge 3 is embedded in circular through-hole 41, the upper surface on stainless steel cap 1 top is pasted tightly to the bottom of acoustic wedge 3, piezoelectric crystal chip 2 sets up in stainless steel cap 1, the top of piezoelectric crystal chip 2 is fixed on the lower surface on stainless steel cap 1 top, the welding has a lead wire 5 respectively on piezoelectric crystal chip 2 and the stainless steel cap 1.
The piezoelectric crystal chip 2 is uniformly provided with a plurality of transverse dividing grooves 21 and radial dividing grooves 22, the transverse dividing grooves 21 and the radial dividing grooves 22 are both long strips penetrating through two ends of the piezoelectric crystal chip, the transverse dividing grooves 21 and the radial dividing grooves 22 are perpendicularly arranged in a cross mode, the piezoelectric crystal chip is uniformly divided into a plurality of square vibrators 23 by the transverse dividing grooves 21 and the radial dividing grooves 22, the upper portions of the square vibrators 23 are separated through the transverse dividing grooves 21 and the radial dividing grooves 22, and the bottoms of the square vibrators are connected together.
The length of the transverse dividing groove 21 is the same as the length of the piezoelectric crystal chip 2, and the length of the radial dividing groove 22 is the same as the width of the piezoelectric crystal chip 2.
The widths of the transverse dividing groove 21 and the radial dividing groove 22 are 0.23mm to 0.27 mm, and preferably 0.25 mm.
The depth of the transverse dividing groove 21 and the radial dividing groove 22 is 2.3-2.4 mm.
The length and the width of the piezoelectric crystal chip 2 are 7.5mm multiplied by 7.5mm, the number of the transverse dividing grooves 21 and the number of the radial dividing grooves 22 are 3, 16 square vibrators 23 with the same size are divided from the piezoelectric crystal chip 2 by the transverse dividing grooves 21 and the radial dividing grooves 22, the length and the width of each square vibrator 23 are 1.66mm-1.70mm multiplied by 1.66mm-1.70mm, and the length and the width of the square vibrator 23 are 1.68mm multiplied by 1.68mm preferably.
The piezoelectric crystal chip described in this embodiment is compared with the piezoelectric crystal chip in the prior art as follows:
as can be seen from comparison of the time differences of the zero flow rate with the temperature change in fig. 6 and fig. 9, the time difference of the zero flow rate with the temperature change of the sensor made of the 7.5 × 7.5 × 1.68 piezoelectric crystal chip divided into the strip-shaped plate in the background art is in the range of 3ns, but the repeatability of the data is poor, and the time difference of the zero flow rate with the temperature change of the sensor made of the 7.5 × 7.5 × 1.68 × 1.68 piezoelectric crystal chip divided into 16 square oscillators in example 1 is in the range of 2ns, but the time difference is smaller and more stable, and the waveform with good repeatability is good.
The impedance and graph shown in fig. 7 and 10, where the Z-curve is a frequency curve, the theta-curve is an impedance curve, by comparison, the resonance frequency of the sensor made of the 7.5 × 7.5 × 1.68 piezoelectric crystal chip which is divided into the strip-shaped plate in the background technology is 538khz, the anti-resonance frequency is 624khz, the center frequency is 580khz, the bandwidth is 86khz, whereas the 7.5 × 7.5 × 1.68 × 1.68 piezoelectric crystal chip divided into 16 square vibrators in example 1 had a resonance frequency of 392khz, an anti-resonance frequency of 592khz, a center frequency of 492khz, a bandwidth of 200khz, by comparison, it can be seen that the sensor made of the piezoelectric transistor chip in the prior art is far more deviated from the center frequency of 500khz, whereas the sensor made of the piezoelectric transistor chip in example 1 is close to the center frequency of 500khz, the bandwidth of the sensor made of the piezoelectric transistor chip in example 1 is increased by 2.3 times compared with the sensor made of the piezoelectric transistor chip in the background art.
As shown in fig. 8 and fig. 11, by comparing the waveform diagrams, it can be found that the sensor made of the 7.5 × 7.5 × 1.68 piezoelectric crystal chip divided into the strip-shaped plate in the background art needs 8 waves to reach the peak value, and the waveform peak value is 19.4mv, whereas the sensor made of the 7.5 × 7.5 × 1.68 × 1.68 piezoelectric crystal chip divided into 16 square oscillators in example 1 needs 6 waves to reach the peak value, and the waveform peak value is 28.4 mv.
To sum up, in embodiment 1, the center frequency of the sensor made of the 7.5 × 7.5 × 1.68 × 1.68 piezoelectric crystal chip divided into 16 square oscillators is closest to 500khz, the bandwidth is 200khz, the sensitivity is increased by 9 mv, the front and rear waveforms are very clean, and the clutter rejection rate is high.
The piezoelectric crystal chip 2 is uniformly provided with a plurality of transverse dividing grooves 21 and radial dividing grooves 22, the transverse dividing grooves 21 and the radial dividing grooves 22 are both long strips penetrating through two ends of the piezoelectric crystal chip, the transverse dividing grooves 21 and the radial dividing grooves 22 are perpendicularly arranged in a cross mode, the piezoelectric crystal chip is uniformly divided into a plurality of square vibrators 23 by the transverse dividing grooves 21 and the radial dividing grooves 22, the upper portions of the square vibrators 23 are separated through the transverse dividing grooves 21 and the radial dividing grooves 22, and the bottoms of the square vibrators are connected together.
The length of the transverse dividing groove 21 is the same as the length of the piezoelectric crystal chip 2, and the length of the radial dividing groove 22 is the same as the width of the piezoelectric crystal chip 2.
The widths of the transverse dividing groove 21 and the radial dividing groove 22 are 0.23mm to 0.27 mm, and preferably 0.25 mm.
The depth of the transverse dividing groove 21 and the radial dividing groove 22 is 2.3-2.4 mm.
The length and the width of the piezoelectric crystal chip 2 are 8.25mm multiplied by 8.25mm, the number of the transverse dividing grooves 21 and the number of the radial dividing grooves 22 are 4, 25 square vibrators 23 with the same size are divided from the piezoelectric crystal chip 2 by the transverse dividing grooves 21 and the radial dividing grooves 22, the length and the width of each square vibrator 23 are 1.43mm-1.47mm multiplied by 1.43mm-1.47mm, and the length and the width of each square vibrator 23 are 1.45mm multiplied by 1.45 mm.
The piezoelectric crystal chip described in this embodiment is compared with the piezoelectric crystal chip in the prior art as follows:
the impedance and graph shown in fig. 7 and 12, where the Z-curve is a frequency curve, the theta-curve is an impedance curve, comparison shows that the resonance frequency of the sensor made of the 7.5 multiplied by 1.68 piezoelectric crystal chip which is divided into the strip-shaped plate in the background technology is 538khz, the anti-resonance frequency is 624khz, the center frequency is 580khz, the bandwidth is 86khz, whereas the sensor made of the 8.25 × 8.25 × 1.45 × 1.45 piezoelectric crystal chip divided into 25 square vibrators in example 2 has a resonance frequency of 404khz, an anti-resonance frequency of 584khz, a center frequency of 494khz, a bandwidth of 180khz, by comparison, it can be seen that the sensor made of the piezoelectric transistor chip in the prior art is far more deviated from the center frequency of 500khz, whereas the sensor made of the piezoelectric transistor chip in example 2 is close to the center frequency of 500khz, the bandwidth of the sensor made of the piezoelectric transistor chip in example 2 is increased by 2.1 times compared with the sensor made of the piezoelectric transistor chip in the background art.
As shown in fig. 8 and fig. 13, it can be seen from the comparison of the waveform diagrams of fig. 8 and fig. 13 that the sensor made of the 7.5 × 7.5 × 1.68 piezoelectric crystal chip divided into the strip-shaped plate in the background art needs 8 waves to reach the peak value, and the waveform peak value is 19.4mv, whereas the sensor made of the 8.25 × 8.25 × 1.45 × 1.45 piezoelectric crystal chip divided into 25 square oscillators in example 2 needs 4 waves to reach the peak value, and the waveform peak value is 22.8 mv.
In conclusion, the center frequency of the sensor made of the 8.25 × 8.25 × 1.45 × 1.45 piezoelectric crystal chip divided into 25 square oscillators is closest to 500khz, the bandwidth is 180khz, the sensitivity is increased by nearly 3.4 mv, the sensitivity is moderate, but the oscillation starting speed is doubled.
The piezoelectric crystal chip is a functional crystal ceramic which has an energy conversion function, can convert mechanical energy into electric energy and convert electric energy into mechanical energy, is a formula formed by mixing a plurality of rare noble metals, is a functional ceramic chip formed by high-temperature synthesis and high-temperature crystallization through a complex production process, and is a positive and negative electrode chip with performance by utilizing high-pressure polarization to form crystal steering after being manufactured through the complex process.
The piezoelectric crystal chip is divided into small vibrators, so that the increase of bandwidth is facilitated, the multipoint resonance is facilitated, the starting vibration speed is facilitated, the consistency of central frequency and the stability of receiving sensitivity are facilitated, the air measurement requirements of various different requirements can be met, the increase of bandwidth is facilitated for the compatibility of the change of drift impedance of the frequency at different temperatures, and the stability and the consistency of the sensor are greatly improved.
The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to practitioners skilled in this art. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.
Claims (10)
1. An ultrasonic sensor, characterized by: the piezoelectric ceramic chip comprises a rubber sleeve (4), a sound wedge (3), a piezoelectric crystal chip (2) and a stainless steel cap (1), wherein the stainless steel cap (1) is installed in the rubber sleeve (4), the sound wedge (3) is embedded into the top end of the rubber sleeve (4), the piezoelectric crystal chip (2) is arranged in the stainless steel cap (1), and a lead (5) is welded on each of the piezoelectric crystal chip (2) and the stainless steel cap (1);
the piezoelectric crystal chip (2) is uniformly provided with a plurality of transverse dividing grooves (21) and radial dividing grooves (22), and the piezoelectric crystal chip is uniformly divided into a plurality of square vibrators (23) by the transverse dividing grooves (21) and the radial dividing grooves (22).
2. An ultrasonic transducer according to claim 1, wherein: the transverse dividing groove (21) and the radial dividing groove (22) are both long strips penetrating through two ends of the piezoelectric crystal chip.
3. An ultrasonic transducer according to claim 1, wherein: the transverse dividing groove (21) and the radial dividing groove (22) are arranged in a vertical crossing mode.
4. An ultrasonic transducer according to claim 1, wherein: the upper part of the square vibrator (23) is separated by a transverse dividing groove (21) and a radial dividing groove (22), and the bottoms are connected together.
5. An ultrasonic transducer according to claim 1, wherein: the length of the transverse dividing groove (21) is the same as that of the piezoelectric crystal chip (2), and the length of the radial dividing groove (22) is the same as that of the piezoelectric crystal chip (2).
6. An ultrasonic transducer according to claim 1, wherein: the width of the transverse dividing groove (21) and the width of the radial dividing groove (22) are 0.23mm-0.27 mm.
7. An ultrasonic transducer according to claim 1, wherein: the depth of the transverse dividing groove (21) and the radial dividing groove (22) is 2.3-2.4 mm.
8. An ultrasonic transducer according to claim 1, wherein: circular through-hole (41) have been seted up at the top of rubber sleeve (4), the lower part of rubber sleeve (4) is equipped with annular groove (42), the continuation limit of stainless steel cap (1) lower extreme is embedded into annular groove (42), the upper surface on stainless steel cap (1) top and the lower surface laminating on rubber sleeve (4) top, sound wedge (3) embedding is in circular through-hole (41), the upper surface on tight stainless steel cap (1) top is pasted to the bottom of sound wedge (3), the top of piezocrystal chip (2) is fixed on the lower surface on stainless steel cap (1) top.
9. An ultrasonic transducer according to claim 1, wherein: the length and the width of the piezoelectric crystal chip (2) are 7.5mm multiplied by 7.5mm, the number of the transverse dividing grooves (21) and the number of the radial dividing grooves (22) are 3, and the transverse dividing grooves (21) and the radial dividing grooves (22) divide 16 square vibrators (23) with the same size in the piezoelectric crystal chip (2).
10. An ultrasonic transducer according to claim 1, wherein: the length and the width of the piezoelectric crystal chip (2) are 8.25mm multiplied by 8.25mm, the number of the transverse dividing grooves (21) and the number of the radial dividing grooves (22) are 4, and the transverse dividing grooves (21) and the radial dividing grooves (22) divide 25 square vibrators (23) with the same size in the piezoelectric crystal chip (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922380764.9U CN212963503U (en) | 2019-12-26 | 2019-12-26 | Ultrasonic sensor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922380764.9U CN212963503U (en) | 2019-12-26 | 2019-12-26 | Ultrasonic sensor |
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| CN212963503U true CN212963503U (en) | 2021-04-13 |
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| CN201922380764.9U Active CN212963503U (en) | 2019-12-26 | 2019-12-26 | Ultrasonic sensor |
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