CN103099684A - Ultrasonic tooth cleaning energy transducer - Google Patents

Abstract

The invention provides an ultrasonic tooth cleaning energy transducer. The ultrasonic tooth cleaning energy transducer comprises a working tip, a variable amplitude rod, a front cover plate and a piezoelectric ceramic plate which is made of a PZT-4 piezoelectric ceramic material, wherein one end of the front cover plate is sleeved into the variable amplitude rod and is connected with the variable amplitude rod, and the piezoelectric ceramic plate is sleeved outside the other end of the front cover plate; a water receiving hole and a first connecting hole are formed in the front cover plate; a first through hole and a second through hole are respectively formed in the working tip and the center of the variable amplitude rod; and the water receiving hole, the first connecting hole, the first through hole and the second through hole are communicated with one another. According to the ultrasonic tooth cleaning energy transducer, on the one hand, a full-vibration mode is selected, water is introduced to a node of the energy transducer, and the performance of the energy transducer is less influenced; and on the other hand, a high-performance PZT-4 piezoelectric material is selected to realize low-voltage driving, so that the ultrasonic tooth cleaning energy transducer has the advantages of excellent performance, high working stability and the like.

Description

A kind of ultrasonic scaling transducer

Technical field

The present invention relates to a kind of oral cavity medical apparatus field, relate in particular to a kind of ultrasonic scaling transducer.

Background technology

At present, the domestic actual ultrasonic scaling transducer that uses exists that the integral handle vibrations are large, easily heating, impedance is large, driving voltage is large.Cause the job stability of traditional ultrasonic scaling transducer inadequate, stream time is short, by analysis, and main weak point following points:

1, the physical dimension of horn is not optimized;

What 2, transducer adopted is half wave mode, and impedance is large, easily heating;

3, water flowing is in the transducer end, and water conduit is very large to the performance impact of transducer.

Summary of the invention

For the problems referred to above, the object of the present invention is to provide the better ultrasonic scaling transducer of a kind of performance, it is the all-wave vibration mode that this ultrasonic scaling transducer is selected vibration mode, impedance is little.

Technical scheme of the present invention is achieved in that

A kind of ultrasonic scaling transducer, the piezoelectric ceramic piece that comprises operation tip, horn, front shroud, PZT-4 piezoceramic material, described front shroud one end is inserted in described horn and is connected with it, the outside sheathed described piezoelectric ceramic piece of the described front shroud other end, described front shroud is provided with water receiving hole and the first connecting hole, described operation tip and described horn center are respectively equipped with the first through hole and the second through hole, and described water receiving hole, described the first connecting hole, described the first through hole and described the second through hole are interconnected.

Preferably, it further comprises back shroud, and described back shroud center is provided with the second connecting hole, and described front shroud is inserted in described the second connecting hole, and piezoelectric ceramic piece is placed between described front shroud and described back shroud.

Preferably, described the first connecting hole, described the second connecting hole and described water receiving hole are screwed hole.

Preferably, described horn external diameter is Φ 8～Φ 15mm, and axial length is 45～50mm.

Preferably, in described piezoelectric ceramic piece, ring diameter is Φ 4～Φ 6mm, and outer ring diameter is Φ 8～Φ 15mm, and thickness is 1～5mm.

Preferably, its center of described operation tip, horn, front shroud, piezoelectric ceramic piece and back shroud point-blank.

Preferably, described ultrasonic scaling transducer total length is 108～130mm.

A kind of method for designing of ultrasonic scaling transducer is characterized in that: described ultrasonic scaling transducer comprises horn and front shroud, and described horn parameter designing satisfies following formula:

$\tan k{l}_1=-\frac{\sin k{l}_1(\cos k^{\&prime;}{l}_2-{\mathrm{\&delta;}}_1\sin k^{\&prime;}{l}_2)-\cos k{l}_3({\mathrm{\&delta;}}_2\cos k^{\&prime;}{l}_2-{\mathrm{\&delta;}}_3\sin k^{\&prime;}{l}_2)}{\cos k{l}_3(\cos k^{\&prime;}{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="HDA00002880498500011.png,HDA00002880498500012.png"\; state="\{\{state\}\}">l</figure-callout>}}_2+{\mathrm{\&delta;}}_4\sin k^{\&prime;}{l}_2)-\frac{k}{k^{\&prime;}}\sin \mathrm{<figure-callout\; id="3"\; label="k\; l"\; filenames="HDA00002880498500011.png,HDA00002880498500012.png"\; state="\{\{state\}\}">k</figure-callout>}{l}_{}{}_3\sin k^{\&prime;}{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="HDA00002880498500011.png,HDA00002880498500012.png"\; state="\{\{state\}\}">l</figure-callout>}}_2}$

Wherein, k' is the wave number of horn, and k is the wave number of front shroud; δ ₁, δ ₂, δ ₃And δ ₄Proportionality constant for horn; l ₁, l ₂And l ₃Each level length for the horn structure.

The beneficial effect that the present invention produces is:

1, the ultrasonic scaling transducer of the present invention's proposition, selecting vibration mode is the all-wave vibration mode, impedance is little;

2, the present invention adopts the horn partial design frequency equation of full-wave to design the sizes at different levels of horn part, and operation mode is more excellent;

3, the present invention selects the high-performance piezoceramic material of PZT-4, and mechanical performance is high, can realize low voltage drive;

4, the present invention is in the water flowing of transducer Nodes, and node is selected in piezoelectric ceramic piece and is close to the front shroud place;

5, the present invention utilizes the admittance characteristic of electric impedance analyzer test energy converting system, the resonant frequency of detection system motion; Utilize displacement amplitude and the mode of oscillation of laser dopper flowmeter vialog test energy converting system end, with the displacement output of detection system; The size of horn obtains through optimal design, can realize that ultrasonic scaling transducer job stability is high, long time continuous working.

Description of drawings

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, the below will do to introduce simply to the accompanying drawing of required use in embodiment or description of the Prior Art, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the main TV structure schematic diagram of an embodiment of a kind of ultrasonic scaling transducer of the present invention;

Fig. 2 be in Fig. 1 A-A to the sectional structure schematic diagram;

Fig. 3 is horn part optimal design schematic diagram in Fig. 1;

In figure: 1 operation tip; 11 first through holes; 2 horn; 21 second through holes; 3 front shrouds; 31 first connecting holes; 32 water receiving holes; 4 piezoelectric ceramic pieces; 5 back shrouds; 51 second connecting holes; 6 aqueducts.

The specific embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, rather than whole embodiment.Based on the embodiment in the present invention, those of ordinary skills belong to the scope of protection of the invention not making the every other embodiment that obtains under the creative work prerequisite.

according to Fig. 1～preferred embodiment shown in Figure 3, a kind of ultrasonic scaling transducer, comprise operation tip 1, horn 2, front shroud 3, the piezoelectric ceramic piece 4 of PZT-4 piezoceramic material and back shroud 5, described front shroud 3 one ends are inserted in described horn 2 and are connected with it, the outside sheathed described piezoelectric ceramic piece 4 of described front shroud 3 other ends, described front shroud 3 is provided with water receiving hole 32 and the first connecting hole 31, described operation tip 1 and described horn 2 centers are respectively equipped with the first through hole 11 and the second through hole 21, described water receiving hole 32, described the first connecting hole 31, described the first through hole 11 and described the second through hole 21 are interconnected.Described back shroud 5 centers are provided with the second connecting hole 51, and described front shroud 3 is inserted in described the second connecting hole 51, and piezoelectric ceramic piece 4 is placed between described front shroud 3 and described back shroud 5.Described the first connecting hole 31, described the second connecting hole 51 and described water receiving hole 32 are screwed hole.Piezoelectric ceramic piece 4 is selected the PZT-4 piezoceramic material in the present embodiment, and its mechanical performance is high, can realize low voltage drive.

PZT is the abbreviation of lead titanate piezoelectric ceramics, and wherein P is the abbreviation of lead element Pb, and Z is the abbreviation of zr element Zr, and T is the abbreviation of titanium elements Ti.The PZT piezoelectric ceramics is that it has direct piezoelectric effect and reversed piezoelcetric effect with Lead oxide brown, lead zirconates, the lead titanates polycrystal that sintering forms under 1200 degree high temperature.It is that lead titanates and lead zirconates solid solution are basic constituent, and its curie point is between 300-400 degree centigrade, and is more stable in larger temperature range, and as transducer material, its piezoelectric effect is remarkable.PZT-4 is the lead with calcium, strontium or barium replacing section, a kind of material made from stannum displacement zirconium, and its curie point reduces, and dielectric constant increases.

Described the first connecting hole 31 hollows, be processed with and the sheathed female thread that is connected of described horn 2 outside it in the present embodiment, and described the second connecting hole 51 is provided with and the sheathed female thread that is connected of described front shroud 3, and it all connects by fixture.Described water receiving hole 32 is arranged at front shroud 3 sides of being close to described piezoelectric ceramic piece 4 in the present embodiment, it is screwed hole, be convenient to connect the water flowing that aqueduct is realized the toothwash process, 3 places connect at front shroud, namely in the Nodes water flowing, it at utmost reduces hyperacoustic performance impact, thereby improves the performance of this ultrasonic scaling transducer, and described aqueduct adopts HPb63-3 to make.In the present embodiment, preferred power plant is ultrasound wave, and described ultrasound wave produces by driving piezoelectric ceramic piece 4, completes the work of ultrasonic scaling transducer.

Described horn 2 one ends are connected with described front shroud 3, and the other end is connected by fixture with described operation tip 1, and in the present embodiment, preferred fixture is the bolt of M3.In the present embodiment, described operation tip 1 adopts traditional operation tip, the bohler manufacturing, and described front shroud 3 and described back shroud 5 adopt the stainless steel 304 manufacturing, and described horn 2 adopts the titanium alloy TC 4 manufacturing.

A kind of method for designing of ultrasonic scaling transducer, wherein horn part sizes at different levels are that design draws according to the horn partial design frequency equation of full-wave, the horn parameter designing satisfies formula:

$\tan k{l}_1=-\frac{\sin k{l}_1(\cos k^{\&prime;}{l}_2-{\mathrm{\&delta;}}_1\sin k^{\&prime;}{l}_2)-\cos k{l}_3({\mathrm{\&delta;}}_2\cos k^{\&prime;}{l}_2-{\mathrm{\&delta;}}_3\sin k^{\&prime;}{l}_2)}{\cos k{l}_3(\cos k^{\&prime;}{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="HDA00002880498500011.png,HDA00002880498500012.png"\; state="\{\{state\}\}">l</figure-callout>}}_2+{\mathrm{\&delta;}}_4\sin k^{\&prime;}{l}_2)-\frac{k}{k^{\&prime;}}\sin \mathrm{<figure-callout\; id="3"\; label="k\; l"\; filenames="HDA00002880498500011.png,HDA00002880498500012.png"\; state="\{\{state\}\}">k</figure-callout>}{l}_{}{}_3\sin k^{\&prime;}{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="HDA00002880498500011.png,HDA00002880498500012.png"\; state="\{\{state\}\}">l</figure-callout>}}_2}$

Wherein, k' is the wave number of horn, and k is the wave number of front shroud; δ ₁, δ ₂, δ ₃And δ ₄Proportionality constant for horn; l ₁, l ₂And l ₃Be each level length of horn structure, l ₁, l ₂And l ₃Be as shown in Figure 3 L1, L2, L3.

Selecting vibration mode in the present embodiment is full-wave, and the design procedure of horn size design formula is:

By continuous elastomeric rod member wave equation:

$\frac{{\&PartialD;}^{2}y}{\&PartialD;x^2}+\frac{1}{S}\frac{\&PartialD;S}{\&PartialD;x}\frac{\&PartialD;y}{\&PartialD;x}+k^{2}y=0---(1-1)$

Its solution is:

$y\left(x\right)=\frac{1}{\sqrt{S}}(C_1\&CenterDot;\cos \left(\mathrm{kx}\right)+{\mathrm{<figure-callout\; id="2"\; label="C"\; filenames="HDA00002880498500011.png,HDA00002880498500012.png"\; state="\{\{state\}\}">C</figure-callout>}}_2\&CenterDot;\left(\mathrm{kx}\right))---(1-2)$

The displacement of each section particle vibration is:

0＜x＜l ₁,y ₁＝a ₁coskx+b ₁sinkx

l ₁＜x＜l ₁+l ₂,y ₂＝R(x)(a ₂cosk'x+b ₂sink'x) (1-3)

l ₂＜x＜l ₂+l ₃,y ₃＝a ₃coskx+b ₃sinkx

A1 in formula, b1, a2, b2, a3, b3 is undetermined constant; In formula, k means cylinder rod member wave number, and k' is circular cone rod member wave number.

Corresponding elastic force is:

0＜x＜l ₁,F ₁＝Ek(-a ₁sinkx+b ₁coskx) (1-4)

l ₁＜x＜l ₁+l ₂,F ₂＝E[R'(x)(a ₂cosk'x+b ₂sink'x)+k'R(x)(-a ₂sink'x+b ₂cosk'x)]

(1-5)

l ₂＜x＜l ₂+l ₃,F ₃＝Ek(-a ₃sinkx+b ₃coskx)

(1-6)

Continuous according to displacement and the power of ultrasonic transmission, can list following equation:

(1) in the x=0 position:

y ₁(0)＝y _i；A ₁F ₁(0)＝-F _i， (1-7)

(2) at x=l ₁The position:

y ₁(l ₁)＝y ₂(l ₁)；A ₁F ₁(l ₁)＝A ₂F ₂(l ₁)， (1-8)

(3) at x=l ₁+ l ₂The position:

y ₂(l ₁+l ₂)＝y ₃(l ₁+l ₂)；A ₂F ₂(l ₁+l ₂)＝A ₃F ₃(l ₁+l ₂)， (1-9)

(4) at x=l ₁+ l ₂+ l ₃The position:

y ₃(l ₁+l ₂+l ₃)＝y _o；A ₃F ₃(l ₁+l ₂+l ₃)＝-F _o＝0 (1-10)

Simultaneous Equations, try to achieve the frequency equation of complex horn:

$\sin k{l}_1(\cos k^{\&prime;}{l}_2-\mathrm{\&alpha;}\sin k^{\&prime;}{l}_2)-\cos k{l}_3(\mathrm{\&beta;}\cos k^{\&prime;}{l}_2-\mathrm{\&gamma;}\sin k^{\&prime;}{l}_2)$

$+\tan k{l}_1(\cos k{l}_3(\cos k^{\&prime;}{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="HDA00002880498500011.png,HDA00002880498500012.png"\; state="\{\{state\}\}">l</figure-callout>}}_2+\mathrm{\&tau;}\sin k^{\&prime;}{l}_2)-\frac{k}{k^{\&prime;}}\sin k{\mathrm{kl}}_3\sin k^{\&prime;}{l}_2)=0---(1-11)$

Wherein,

$\mathrm{\&alpha;}=\frac{1}{k^{\&prime;}}\left[\frac{R^{\&prime;}\left(0\right)}{R\left(0\right)}\right]$

$\mathrm{\&beta;}=\frac{1}{k}[\frac{R^{\&prime;}\left(l_2\right)}{R\left(l_2\right)}-\frac{R^{\&prime;}\left(0\right)}{R\left(0\right)}]$

$\mathrm{\&gamma;}=\frac{1}{k{k}^{\&prime;}}[{k^{\&prime;}}_2+\frac{R^{\&prime;}\left(l_2\right)}{R\left(l_2\right)}\frac{R^{\&prime;}\left(0\right)}{R\left(0\right)}]$

$\mathrm{\&gamma;}=\frac{1}{k^{\&prime;}}\left[\frac{R^{\&prime;}\left(l_2\right)}{R\left(l_2\right)}\right]$

Formula (1-11) is for determining the foundation of horn part basic size, utilize computer language (Matlab) can computing formula in the provisional value of parameter.

Table 1-1 has listed the design parameter that different horn types are used.

Table 1-1

(1) verify based on the energy converting system of Finite Element

Utilize software ANSYS ANSYS that the energy converting system of being set up by the one dimension elastic wave theory is verified, obtain frequency distribution, mode of oscillation and the corresponding vibration shape of energy converting system;

(2) energy converting system processing and assembling

By the physical dimension of each parts, the energy converting system each several part is processed, utilize the assembling of pointer ergometer, follow in operating process:

Its center of described operation tip, horn, front shroud, piezoelectric ceramic piece and back shroud point-blank, described piezoelectric ceramic piece 4 is 0.02～0.06 with described horn 2 axialities, in the present embodiment, during assembling, piezoelectric ceramic piece 4 is 0.04 with the axiality of horn 2, can realize that described piezoelectric ceramic piece 4 coordinates closely with described horn 2 through holes, thereby strengthen the job stability of described ultrasonic scaling transducer.

(3) energy converting system Performance Detection

Utilize the admittance characteristic of electric impedance analyzer test energy converting system, the resonant frequency of detection system motion; Utilize displacement amplitude and the mode of oscillation of laser dopper flowmeter vialog test energy converting system end, with the displacement output of detection system.

Through optimal design, the total length of the horn 2 that the transducer performance of full-wave vibration is good is 45～50mm, and described horn 2 external diameters are Φ 8～Φ 15mm, and preferred horn 2 external diameters of the present embodiment are Φ 10mm.Ultrasonic scaling transducer total length is 108～130mm, and the external diameter of the preferred described front shroud 3 of the present embodiment is 20mm, and the transducer overall length is 110mm～120mm.

Described piezoelectric ceramic piece 4 is selected the high-performance piezoceramic material of PZT-4, its good mechanical property, can realize low voltage drive, the interior ring diameter of described piezoelectric ceramic piece 4 is Φ 4～Φ 6mm, outer ring diameter is Φ 8～Φ 12mm, thickness is 1～5mm, and in the present embodiment, preferred piezoelectric ceramic piece 4 is of a size of Φ 11.5 * Φ 5.3 * 1.25mm.

Utilize electric impedance analyzer to carry out sweep check to transducer in the present embodiment, the resonant frequency of detection system can get the operating frequency of system in the 30kHz left and right; Utilize the laser dopper flowmeter tester to detect the displacement output of transducer end, the output displacement that can get system is the 20um left and right, meets the requirement of ultrasonic tooth.

The present invention adopts full vibration mode, and impedance is little, and the size of horn obtains through optimal design, can realize that ultrasonic scaling transducer job stability is high, long time continuous working.

The above is only preferred embodiment of the present invention, and is in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, is equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims (8)

1. ultrasonic scaling transducer, the piezoelectric ceramic piece that comprises operation tip, horn, front shroud, PZT-4 piezoceramic material, it is characterized in that: described front shroud one end is inserted in described horn and is connected with it, the outside sheathed described piezoelectric ceramic piece of the described front shroud other end, described front shroud is provided with water receiving hole and the first connecting hole, described operation tip and described horn center are respectively equipped with the first through hole and the second through hole, and described water receiving hole, described the first connecting hole, described the first through hole and described the second through hole are interconnected.

2. ultrasonic scaling transducer as claimed in claim 1, it is characterized in that: it further comprises back shroud, described back shroud center is provided with the second connecting hole, and described front shroud is inserted in described the second connecting hole, and piezoelectric ceramic piece is placed between described front shroud and described back shroud.

3. ultrasonic scaling transducer as claimed in claim 2 is characterized in that: described the first connecting hole, described the second connecting hole and described water receiving hole are screwed hole.

4. ultrasonic scaling transducer as claimed in claim 1, it is characterized in that: described horn external diameter is Φ 8～Φ 15mm, and axial length is 45～50mm.

5. ultrasonic scaling transducer as claimed in claim 1 is characterized in that: in described piezoelectric ceramic piece, ring diameter is Φ 4～Φ 6mm, and outer ring diameter is Φ 8～Φ 15mm, and thickness is 1～5mm.

6. ultrasonic scaling transducer as claimed in claim 1 is characterized in that: described operation tip, horn, front shroud, piezoelectric ceramic piece and back shroud its center point-blank.

7. ultrasonic scaling transducer as claimed in claim 1, it is characterized in that: described ultrasonic scaling transducer total length is 108～130mm.

8. the method for designing of a ultrasonic scaling transducer, it is characterized in that: described ultrasonic scaling transducer comprises horn and front shroud, described horn parameter designing satisfies following formula:

$\tan k{l}_1=-\frac{\sin k{l}_1(\cos k^{\&prime;}{l}_2-{\mathrm{\&delta;}}_1\sin k^{\&prime;}{l}_2)-\cos k{l}_3({\mathrm{\&delta;}}_2\cos k^{\&prime;}{l}_2-{\mathrm{\&delta;}}_3\sin k^{\&prime;}{l}_2)}{\cos k{l}_3(\cos k^{\&prime;}{l}_2+{\mathrm{\&delta;}}_4\sin k^{\&prime;}{l}_2)-\frac{k}{k^{\&prime;}}\sin k{l}_3\sin k^{\&prime;}{l}_2}$

Wherein, k' is the wave number of horn, and k is the wave number of front shroud; δ ₁, δ ₂, δ ₃And δ ₄Proportionality constant for horn; l ₁, l ₂And l ₃Each level length for the horn structure.

Images