High-voltage generator and method of its manufacture

FIELD: electricity.

SUBSTANCE: invention relates to piezoelectronics. Essence of the invention: the working body of the high-voltage generator is formed by inertial mass and a package of the plates of polarised composite ferroelectric materials with high values of piezoelectric voltage coefficient and compressive strength pre-set for each plate. The distances between the conducting surfaces applied on the plates is set such that their values multiplied by values of mechanical stress and piezoelectric stress coefficient be identical to each plate in the package. The method comprises the manufacture of each batch of the plates polarised composite ferroelectric materials by consecutive execution of the following operations: preparation of moulding powder of the synthesised material, preparation of mix of moulding powder of the synthesised material and pore agent, moulding from mix of work-pieces and their high-temperature processing by an agglomeration method, machining, metallisation, polarisation and measurement of parameters. The pre-set compressive strength for each batch of plates is achieved by a porosity variation due to change of concentration of pore agent in the plate.

EFFECT: conversion of mechanical compression stress to electric energy without explosive, reduction of time of formation and increase of occurring electric charge in unit of volume of the working body at high values of potential difference.

2 cl, 2 dwg, 2 ex

 

The invention relates to electronics, and more specifically, to piezoelectronic, converters of mechanical energy into electrical energy, to the sources of the electric charge of high voltage-based piezoelectric ceramics.

Known piezoelectric devices - mechanical energy Converter into electrical energy. The transformation of energy by deformation of the piezoelectric element consisting of a polarized ferroelectric ceramics, occurs in the piezoelectric sensors (V. V. Ancic. Piezoelectric transducers. Rostov-on-don, Publishing house "SFU", 2010), and in household appliances - pezozazhigalok - formed high-voltage discharge. When the longitudinal relative to the residual vector polarized, deformation of the compression-tension of the piezoelectric element under the action of a force applied normal to the planes of the electrodes by a piezoelectric effect, the electrodes of the charge.

Known explosive generators for meteorological applications, which converts the mechanical energy of the shock wave propagating in the working medium, high voltage electrical energy (Presedence A. B., D. V. Tretyakov, Sekachev M. V. the energy Balance of the explosive piezoelectric oscillator frequency. Proceedings of the conference "Magagawa and Meg�voltage application technology", Sarov, VNIIEF, 1997, p. 954÷958). The main element of such generators is the working medium, for execution as a batch of n wafers polarized ferroelectric material coated with conductive surfaces. The shock wave in the working medium is formed by a special explosive charge. The advantages of the considered devices are compact and can be completely Autonomous from external power sources.

The explosive shock wave has a greater intensity, and the dominant process in the conversion of mechanical energy of the shock wave into electrical energy is the transition of ferroelectric paraelectric state in.

Source current iEand the resulting charge Q, under the assumption about linearity of the material properties of the working fluid, can be estimated by the formulas:

where: n is the number of plates of the ferroelectric material coated with conductive surfaces;

Δ - leap of polarization at the shock front;

uE- the velocity of the shock wave front, uEequate to the speed of sound in the working medium;

SE- the area of the contact surfaces of the ferroelectric working body;

δ=nh - the path of the shock wave ferroelectric working body;

h - the distance between the contact�and ferroelectric surfaces of the plates;

t=δ/uEthe current flow.

Known explosive piezoradiator (patent RF №2154888, prototype) comprises a shock wave generator, a piezoelectric transducer shock wave energy into electrical energy, in the form of one piezoplates with electrodes on two opposite faces parallel to the direction of propagation of the shock wave.

The disadvantages of these designs include a high voltage generator:

- in the presence of explosive generators explosives and the accompanying system initialization to create a shock wave;

- the presence of a source of electrical energy (battery, batteries and electronic components for the formation of high voltage;

- relatively small values of emerging charge per unit volume of the working fluid when high values of the potential difference applied between the plates of the conductive surfaces.

Task to be solved by the present invention is, while maintaining the advantages (compactness and full autonomy), the achievement of the technical result is:

- in the creation of a high-voltage generator, which excludes the presence of explosives, which converts the mechanical shock in high voltage electrical energy through working�about the body of piezoelectric high voltage generator under the influence of a shock wave for example, in shot volume type VOG-25 grenade launcher type GP-25;

- reduced time of education and increase the value of emerging electric charge per unit volume of the working fluid at high values of the potential difference applied between the plates of the conductive surfaces.

The problem is solved in piezoelectric high voltage generator consisting of an inertial mass and laminations polarized ferroelectric composite materials with high piezoelectric voltage coefficient and defined for each plate compressive strength, mechanically connected in series so that the resulting plate at impact mechanical stresses are added together and electrically connected in parallel so that the cumulative arising in plates electric charges with the same potential difference, which is the distance between a deposited conductive plate surfaces are set such that their values are multiplied by the values of mechanical stress and piezoelectric voltage coefficient, were the same for each plate in the package, and the working fluid is subjected to a shock wave; and placed, for example, in shot volume type VOG-25 grenade launcher t�PA GP-25.

The inventive high-voltage generator and the properties of its constituent elements illustrated by Fig. 1 and 2, Tab. 1.

Fig. 1A is a Mechanical diagram of a piezoelectric high voltage generator.

Fig. 16 is an Electric circuit of a piezoelectric high voltage generator.

Fig. 1B - dimensions shots VOG-25.

M0- inertial mass.

1÷6 - plate density ρkpolarized ferroelectric composite materials with high values of the piezoelectric voltage coefficientand specified for each k-th plate compressive strength

7 - electrodes,

8 - mounting tape silver,

9 - inserts - electrode current collector,

10 - the case of porous polymeric material,

11 - the polarization direction of each plate,

- the direction of movement of the generator at the Ular,

- the direction of compression forces (inertia) at impact.

Fig. 2 the dependence of the properties of piezoelectric ceramics with closed porosity (connectivity 3-0) from porosity.

Fig. 2A. The dependence of pesumably d of the porosity P of the piezoelectric ceramics with closed porosity.

d33- longitudinal piezomodule;

dvvolume piezomodule;

d31- cross piezomodule.

Fig. 2�. The dielectric permittivityε33Tfrom porosity P of piezoceramic with closed porosity.

Fig. 2B. The dependence of the compressive strength of TSGfrom the porosity P of the piezoelectric ceramics with closed porosity.

Table 1. Characteristics properties of piezoplates the working fluid of the high-voltage generator.

Table 2. Characteristics properties of the plates of the working body, made of a polarized ferroelectric material.

k - serial number plates;

Pk- the porosity of the k-th plate, %;

ρkis the density of the k-th plate, kg/m3;

T33k- mechanical stresses arising in the k-th plate, 108PA;

ε33Tk- the dielectric constant of the k-th wafer;

g33kis the piezoelectric voltage coefficient of the k-th plate,·m/N;

hk- the distance between the conductive surfaces of the k-th plate, m;

Qkthe charge arising in the k-th plasti�e, CL;

Uk- the potential difference of charges on the conductive surfaces of the k-th wafer;

Xk- the concentration of blowing agent input for the k-th plate with a specified compressive strength, wt. %. In polarized ferroelectric composite materials connectivity 3-0, which corresponds ceramics with closed porosity, while increasing its porosity P from ≈0 to ≈50% piezomodule d33is almost constant, and dielectric constantε33Tand the compressive strength of TSGdecrease, as shown in Fig. 2A), 26) and 2B) and in the range 0≤P≤30% change of ε33(P), g33(P) and TSG(P) determined experimentally and are described by formulas:

whereε33T1,g331,TCW1- characteristics of "non-porous ceramics, which corresponds to a sintered without blowing agent.

The characteristics of the "non-porous" to�ramici, the respective sintered without blowing agent to the models appearing in line 1 of Table 1 and shown in Fig. 2.

In the proposed design of the high-voltage generator (Fig. 1A), placed, for example, in shot volume type VOG-25 (Fig. 1B), the working fluid represents the inertial mass M0and the batch of n wafers polarized ferroelectric composite materials (Fig. 1B) the density ρkwith high values of the piezoelectric voltage coefficientand specified for each k-th plate having a compressive strength ofTCWkand mechanical plate are connected in series so that the resulting plate upon impact with velocity V mechanical stressT33ksummed up, but electrically connected in parallel so that the cumulative arising in plates electric charges with the same potential difference Uk, what distance hkbetween applied to the conductive plate surface area of Skset such that the values of hkmultiplied by the values of the mechanical stresses T33kand piezoelectric voltage coefficientg33kin the same wayfor each plate of the working fluid.

Characteristics of the k-th plate of the high voltage generator according to previously identified and presented experimental regularities and constants are described by the following formulas

Plates in the package are connected mechanically in series so that the mechanical stressesT33kin the k-th plate upon impact of the generator parallel to the direction of polarization, and their maximum values in the plates are:

- for "header", the n-th plate (k=n)

- for the k-th plate

where a is the acceleration voltage of the generator at a blow;

Sn- contact surface, "upper", the n-th plate.

Equating for the k-th inserts the value ofT33kthe value of compressive strength of TCWkaccording to the dependency characteristics of polarized ferroelectric composite materials from porosity Pkshown in formulas (3) (4) and (5) determine the desired porosity Pkcomposite and porosity corresponding to that permittivity valuesε33Tk.

Plates are connected electrically in parallel so that summarized the emerging electric charges with the same potential differencefor what value of the distance hkdetermined from the continuity condition worksfor each plate.

The maximum time of occurrence of charges with the same potential difference Ukit can be estimated at the time of passage of the shock wave (compression wave) at the plate with a maximum value of hkthat is substantially less than the transit time of a wave of compression consistently across all plates.

When the acceleration values that contribute to the excess of the compressive strength, the process of conversion of mechanical energy of compression into electrical energy occurs simultaneously in all the plates of the working fluid and with�avoideda leap of polarization on the wave front of the compression in the transition of ferroelectric paraelectric state in.

The increase in the value of emerging electric charge per unit volume of the working fluid at high values of the potential difference applied between the plates of the conductive surfaces follows from the dependences in Fig. 2A) and 2B).

Fig. 2A schematically shows the dependence of pesumably d33and d31and dvfrom porosity R. If the values of the transverse piezomodule d31with increasing porosity decreases, the volumetric piezomodule dvgrows, the amount of longitudinal piezomodule d33that determines the charge remains practically unchanged, and the value of the coefficient of the voltage is proportional towith increasing porosity increases.

Thus, the hallmark of a high voltage generator that converts the energy of the shock wave mechanical compression into electrical energy, is the working fluid that is subjected to a shock wave, for example, in shot volume type VOG-25 grenade launcher type GP-25, which represents an inertial mass and the laminations of polarized ferroelectric composite materials with high piezoelectric voltage coefficient and defined for each plate compressive strength, mechanically connected in series so that who�typewriter in plates under impact, the mechanical stresses are summed, and electrically connected in parallel so that the cumulative arising in plates electric charges with the same potential difference, which is the distance between a deposited conductive plate surfaces are set such that their values are multiplied by the values of mechanical stress and piezoelectric voltage coefficient were the same for each wafer in the batch.

The specified set of distinctive features of the invention allows to achieve a technical result consists in:

- the establishment of a piezoelectric high voltage generator charge, for example, in shot volume type VOG-25 grenade launcher type GP-25, which converts the mechanical compressive stress arising from the shock generator to electrical energy and eliminating any explosive substance;

- reduction of time of education and increase the value of emerging electric charge per unit volume of the working fluid at high values of the potential difference applied between the plates of the conductive surfaces.

The formation of the electric charge occurs simultaneously in all the plates and can be assessed at the time of passage of the compression wave on the plate with the greatest distance between the conductive surfaces. Difference p�of tentelow charges on the conductive surfaces of the plates are the same and equal to

A method of manufacturing the inventive high-voltage generator. The process of manufacture of high voltage generators includes the manufacture of:

- plates of polarized ferroelectric composite materials with high piezoelectric voltage coefficient and defined for each plate compressive strength;

packages of plates mechanically connected in series (in a column) so that arise in the plates during acceleration mechanical stresses are added together and electrically connected in parallel so that the cumulative arising in plates electric charges;

build a high voltage generator in the case of a porous polymeric material, including Assembly of the working fluid from the inertial mass and the package of plates and current collectors, in the case of a porous polymeric material.

The process of manufacturing plates of porous piezoelectric ceramics for generator starts with the preparation of batches of mixtures of press powder synthesized material powder and a blowing agent, e.g. corn starch or methylcellulose. Press the powder of the synthesized material, for example PZT-46, is made from powder synthesized material having a total specific surface area in the range of (1±0,1) m2/g device PSC-4, and the size zere� powders organic blowing agent, for example methylcellulose, Ø=6±1 µm. For each plate a batch of a mixture prepared separately in the apparatus of the mixing vortex layer (ABC), where the chaotic motion of magnetic working media, such as steel needles for gramophones, is determined by the rotating magnetic field of the stator three-phase motor. Volumetric content of blowing agent in the mixture is laid during loading and is controlled by the value of the bulk weight of the mixture.

Pressing batches of mixtures of powders produced in the moulds, the size of which take into account shrinkage during sintering up to 45% and the required machining allowances.

The sintering of the preforms is carried out in a lead-containing filling for special temperature-time mode, which provides the temperature rise at a rate of 25±3°C/h, holding at the temperature of 450±10°C for a 2.0±0.1 hour to burn off the ligaments and blowing agent powder; sintering is carried out at a temperature of 980±10°C for 3 hours.

Sintered workpiece is polished by diameter and, as a purely in-plane, with an allowance for height up to 5 mm.

On the grinded workpieces determine the density of geometrically as the ratio of mass to volume (weighing in the balance with an error of not more than 0.1%, the sizing of the caliper with a scale division of 0.01 mm. the Total error of determining the density is estimated as not offset�sort of 1.0%. Polished billet optionally, up to 10% of each batch is made probes, determine electrophysical parameters and subjected to compression in a hydraulic press, determining the compressive strength.

Billet parties with different density (porosity) grind in size according to the height defined by the probes, in accordance with the computed values.

The metallization of porous flat surfaces of the workpieces is carried out in the traditional way, with the application of silver paste through screen printing with edges and a silver-containing brazing paste with the value of porosity up to 25% when the porosity is closed. In the blanks with open (through) porosity (greater than 25%) by brazing with silver metallization occurs only pads, and then sprayed through a mask with silver edges on all flat surfaces.

The polarization of the workpieces is carried out on the modes selected on the probes, for example at a temperature of 120±3°C and the field strength of 2.0±0.1 kV/mm in an hour.

The described method uses known technology, but does not ensure the production of plates with the required set of parameters.

The problem to be solved by the present invention is the achievement of the technical result

in support of the technological capabilities of manufacturing layer�n polarized ferroelectric composite materials with high piezoelectric voltage coefficient and defined for each plate compressive strength with such distances between plotted plate on conductive surfaces, so that their values are multiplied by the values of mechanical stress and piezoelectric voltage coefficient were the same for each batch of plates.

The problem is solved when using the method of manufacturing a piezoelectric high-voltage generator consisting of a body of porous polymeric material with embedded electrodes, current collectors and the working fluid, comprising an inertial mass and the laminations of polarized ferroelectric composite materials with high piezoelectric voltage coefficient and defined for each plate compressive strength, and the production of each batch of plates of polarized ferroelectric composite materials with specified compressive strengths include: - preparation of press powder synthesized material, mixing press powder synthesized material and the blowing agent, extrusion of a mixture of workpieces and high temperature treatment (sintering), machining, plating, polarization and measurement of parameters, characterized in that:

- the party mix press powder with a blowing agent for the k-th plate with a specified compressive strength ofTC kand porosity PKcontains a blowing agent at a concentration of XKwt. cent;

whereKICob- coefficient of volumetric shrinkage of the piezoelectric materialKICob=1,455;

ρn/Ris the density of the blowing agent ρn/R=1.2 g/cm3;

ρWG- x-ray density of the piezoelectric material, ρWG=8,02 g/cm3;

ρPR- compaction, ρPR=5.2 g/cm3;

a Pkis calculated from the dependence of the

whereTCW1- the compressive strength of "non-porous" ceramics first, the most remote from the inertial mass, plate,TCW16108Pa;

and acceleration at impact a=(1,3÷1,5)·106m/s2;

ρ1density - b�sporitel" first ceramics, the most remote from the inertial mass of the plate, ρ1=7,8·103kg/m3;

ρkis the density of the k-th plate ρkWG·(1-Pk/100),

hk- the distance between applied to the wafer conductive surfaces,

- UK- the potential difference of charges on the conductive surfaces of the plates Uk≈105In;

but all these boil down to a work Table 1, the values of the parameters in which check on the probes;

for the first, the most remote from the inertial mass of the plate, the values of the parameters given in the first line of Table 1, with the parameters of the inertial masses are determined from the formulas:

F=T33nSn=M0a; M00Snh0therefore

M0=T33nSn/aand h0=M0(P0Sn)

where: ρ0is the density of inertial mass,

h0- the height of the inertial mass,

T33n - the compressive strength of the top plate adjacent to the inertial mass (k=n=6);

Sn- contact surface, "upper", the n-th plate.

Sample calculations in the manufacture of piezoelectric high-voltage generators.

Acceleration and arising in the plates upon impact of the high-voltage generator is estimated as=(1,2÷1,5)106m/s2(~105g).

Example 1. Piezoelectric high voltage generator for converting mechanical energy into electricity, in which the working fluid represents the inertial mass M0and the laminations of polarized ferroelectric composite material, wherein each plate has its own corresponding values for density, compressive strength and dielectric constant.

Piezoelectric high voltage generator converts the mechanical compressive stress, resulting from an impact oscillator with acceleration a=1,282·106m/s2to electrical energy with a potential difference of charges on the conductive surfaces of the plates Uk=105V.

The acceleration a=1,282·106m/s2corresponds to the change in generator speed to 70 m/s to zero at a distance L=1,9·10-3m for 5,46·10-5S.

Overall dimensions: diameter D=38 mm, height h<65 mm.

p> These dimensions satisfy the Seating size of the shot type VOG-25 grenade launcher type GP-25 (Fig. 1B).

Features polarized composite "non-porous" ferroelectric material when the value of the porosity P1≈0-2,7%:

the mechanical compressive strength ofTCW1=6108Pa.

The values of compressive strength and dielectric constant of each of the plates of polarized ferroelectric composite materials with the porosity values of Pkin the range 0≤Pk≤30% determined by the formulas (3), (4) and (5).

Emerging in the plates when the acceleration a mechanical stress are summarized, and their maximum values in the plates are:

- for "header", the n-th plate (k=n)

- for the k-th plate

for the first, the lower plate

At the same time for the first plate, the maximum value ofT331=TCWand brushless�Tiki composite "non-porous" ferroelectric material corresponding to the above values when the porosity P≈0-2,7%:

To obtain the potential difference Uk=105In the first plate, with the porosity P1≈0-2,7%, the distance h1between the conductive surfaces will be:

Charge

For the second plate

This value is the limit of compressive strength, in accordance with formula (5), describes a composite with a porosity of P2=8,2%, for which the main parameters in accordance with formula (3), defined as:

d33=500·10-12TC/N;

To obtain the potential difference of charges on the conductive surfaces of the plates Uk=105In the distance h2between the conductive surfaces of the second polarized plate of composite material with a porosity of P2≈8.2 percent will be equal to

Charge

For the third and subsequent wafers calculations carried out analogously, the results are shown in Table 1.

The number of plates in the unit is limited to 6, since the porosity of the plate No. 7 will be more than 30% and is beyond the scope of formula (3), (4) and (5).

The mechanical stress acting on the surface 6 of the plate is equal to 3.56·108PA corresponds to the inertial mass of M0=0,315 kg, which can produce a� material layer height 35.6 mm at a density of 7800 kg/m 3.

The total height of the reporting unit, excluding the thickness of the electrodes, 64,4 mm, which corresponds to the imposed conditions.

Fig. 1 shows a diagram of the device according to the example 1.

- the direction of the velocity vectors and stress.

Example 2. A piezoelectric device for converting mechanical energy into electrical energy, characterized in that the working body is the inertial mass M0andthe laminations "non-porous" polarized ferroelectric material.

The piezoelectric device converts the mechanical compressive stress arising from the acceleration of the device and=1,282·106m/s2to electrical energy with a potential difference of charges on the conductive surfaces of the plates Uk=105V.

Characteristics of a polarized ferroelectric material is the same for all plates of the device:

d33=500·10-12TC/N;

ε33T=2000;

ρ=7,8·103kg/m3;

the mechanical compressive strength of TSG≥6·108PA

Overall dimensions: diameter D=38 mm, height h<65 mm.

Also, in the p�moat example, emerging in plates under acceleration and mechanical stresses are summarized, and their maximum values in the plates are:

- for "header", the n-th plate

- for the k-th plate

for the first, the lower plate

For the first plateT331=TCW1and the distance h1between the conductive surfaces, which corresponds to the potential difference Uk=105In, is defined as

Charge

For the second plate

Since other parameters of the second plate identical to the first plate, the distance h2necessary for the potential difference U2=105B, is defined as

The charge for the second plate

Similarly defined byT33k, hkand Qkfor plates with k=3, 4, 5 and 6; these values are summarized in Table 2. The parameter values for the plate with k=7

(h7=0,157 m) exceed�have overall dimensions of the device.

The mechanical stress acting on the surface 6 of the plate is equal to 0,23·108PA corresponds to the inertial mass of M0=0.02 kg, which can create a layer of material with a height of 2.3 mm at a density of 7800 kg/m3.

The total height of the reporting unit, excluding the thickness of the electrodes,<60,1 mm, which corresponds to the imposed conditions.

In the device discussed in example 1 (composite material), the values of emerging electric charge per unit of the total volume of the working fluid in 1,13 more than the device discussed in example 2 (without composite material). If you compare the volume of ferroelectric materials, the advantage of the device in the first example will be 2.28 times.

A method of manufacturing

The technological process of manufacturing the high voltage generator includes three stages.

1.) 1) the First stage is the production of plates of polarized ferroelectric composite materials with high values of the piezoelectric voltage coefficient and defined for each plate compressive strength,

2) the Second stage is the manufacturing of laminations, mechanically connected in series so that arise in the plates during acceleration mechanical stresses are added together and electrically connected in parallel so that emerged are summarized�incorporate in plates electric charges

3) Third stage - production of the generator in the case of a porous polymeric material, including Assembly of the working fluid from the inertial mass and the package of plates and current collectors in the housing.

1) the First stage is the production of plates of polarized ferroelectric composite materials

The process of manufacturing plates of porous piezoelectric ceramics includes

1.1. preparation of powder of the synthesized material, for example PZT-46, having a total specific surface area in the range of 1.0±0.1 m2/g device PSC-4;

1.2. preparation of press powder from the powder synthesized material;

1.3. calculating the concentration of the blowing agent according to the formula:

whereKICob- coefficient of volumetric shrinkage of the piezoelectric materialKICob=1,455;

Pn/Ris the density of the blowing agent, Pn/R=1.2 g/cm3;

PWG- x-ray density of the piezoelectric material, PWG=8,02 g/cm3;

Pnp- compaction, Pnp=5.2 g/cm3;

and Pkthe porosity is defined for each of participa values in column 2 of Table 1 to provide the required parameters of the party of piezoelectric elements.

1.4. Cooking parties are a mixture of powder of the synthesized material and the blowing agent in the apparatus of the vortex layer (ABC), where the chaotic motion of magnetic working media, such as steel needles for gramophones, is determined by the rotating magnetic field of the stator three-phase motor.

1.5. Pressing batches of mixtures of powders is carried out in molds, the dimensions of which take into account shrinkage during sintering up to 20-45% and the required machining allowances.

1.6. The sintering of the preforms is carried out in a lead-containing filling for special temperature-time mode, which gives the temperature rise at a rate of 25±3°C/h, holding at the temperature of 450±10°C for a 2.0±0.1 hour to burn off the ligaments and blowing agent powder; sintering at a temperature of 980±10°C for 3 hours.

1.7. Grinding the sintered billets diameter in size 38-0,1mm and, as a purely in-plane, with an allowance for height up to 5 mm.

1.8. Determination of the density of each batch of workpieces geometrically as the ratio of mass to volume (weighing in the balance with pogreshnosti not more than 0.1%, the sizing of the caliper with a scale division of 0.01 mm.)

1.9. The manufacturer for each batch of samples, determination of physical parameters, pressure on the hydraulic press and the determination of the compressive strength.

1.10. Cone�WAC billets parties with different density (porosity) in size, in height, determined on the samples, in accordance with the values in column 7 of table 1,

1.11. Metallization of the porous flat surfaces of the workpieces in the traditional way, with the application of silver paste through a silk stencil with edges and a silver-containing brazing paste with the value of porosity up to 25% when the porosity is closed. In the blanks with open (through) porosity (greater than 25%) by brazing with silver metallization occurs only pads, and then sprayed through a mask with silver edges on all flat surfaces.

1.12. The polarization of the blanks on the modes selected on the probes, for example at a temperature of 120±3°C and the field strength 2±0.1 kV/mm in an hour.

Thus, the distinguishing feature of the method of manufacturing a piezoelectric high-voltage generator consisting of a body of porous polymeric material with embedded electrodes, current collectors and the working fluid, comprising an inertial mass and the laminations of polarized ferroelectric composite materials with high piezoelectric voltage coefficient and defined for each plate compressive strength, and the production of each batch of plates of polarized ferroelectric composite materials with specified compressive strength includes Opera�AI: - preparation of press powder synthesized material, mixing press powder synthesized material and the blowing agent, extrusion of a mixture of workpieces and high temperature treatment (sintering), machining, plating, polarization and measurement of parameters, characterized in that:

- the party mix press powder with a blowing agent for the k-th plate with a specified compressive strength ofTCWkand porosity PKcontains a blowing agent at a concentration of Xkwt. cent;

whereKICob- coefficient of volumetric shrinkage of the piezoelectric materialKICob=1,455;

Pn/Ris the density of the blowing agent, Pn/R=1.2 g/cm3;

PWG- x-ray density of the piezoelectric material, PWG=8,02 g/cm3;

ρnp- compaction, ρnp=5.2 g/cm3;

a Pkis calculated from the dependence of the

where TCW1- the compressive strength of "non-porous" ceramics first, the most remote from the inertial mass, plate,

and acceleration at impact a=(1,3÷1,5)·106m/s2,

ρ1- the density of non-porous ceramics first, the most remote from the inertial mass of the plate, ρ1Is 7.8·103kg/m3;

ρkis the density of the k-th of the plate, ρkWG·(1-PK/100);

hk- the distance between plotted on the k-th conductive plate surfaces

- UK- the potential difference applied between the plates of the conductive surfaces UK≈105In;

and all the data are in a spreadsheet type of table 1, the values of the parameters in which check on the probes; wherein the parameters of the inertial masses are determined from the formulas:

where ρ0is the density of inertial mass;

h0- the height of the inertial mass;

T33n- the compressive strength of the top plate adjacent to the inertial mass (k=n=6);

Sn- square pin�th surface, "top", the n-th plate.

For the first, the most remote from the inertial mass of the plate parameter values given in the first line of Table 1.

1. The high-voltage generator with a working body consisting of a polarized ferroelectric material, characterized in that the generator housing is made of a porous polymer material with embedded electrodes, current collectors, and the working fluid further comprises an inertial mass, wherein the ferroelectric material is a pack of plates of polarized ferroelectric composite materials with high piezoelectric voltage coefficient and defined for each plate compressive strength, so
- for "header", the n-th plate (k=n)

- for the k-th plate

whereTCWnandTCWk- the compressive strength of the n-th plate and the k-th wafer;
TCWnandT33k - emerging in the n-th plate and the k-th plate mechanical stresses upon impact with acceleration and inertial mass M0;
Sn- contact surface, "upper", the n-th wafer;
ρ and h is the density of the plate and the distance between the contact surfaces of the plate respectively,
mechanically connected in series so that the resulting plate at impact mechanical stresses are added together and electrically connected in parallel so that the cumulative arising in plates electric charges with the same potential difference, which is the distance between a deposited conductive plate surfaces are set such that their values are multiplied by the values of mechanical stress and piezoelectric voltage coefficient were the same for each wafer in the batch.

2. A method of manufacturing a piezoelectric high-voltage generator consisting of a body of porous polymeric material with embedded electrodes, current collectors and the working fluid, comprising an inertial mass and the laminations of polarized ferroelectric composite materials with high values of the piezoelectric voltage coefficient and defined for each plate compressive strength containing the manufacture of each batch of plates field�Savannah ferroelectric composite materials with a specified compressive strength, including operations: preparation of press powder synthesized material, preparation of a mixture of press powder synthesized material and the blowing agent, extrusion of a mixture of workpieces and heat treatment by sintering, machining, plating, polarization and measurement of the parameters, characterized in that the technological process of manufacturing the high voltage generator includes three stages:
the first stage is the production of plates of polarized ferroelectric composite materials with high values of the piezoelectric voltage coefficient and defined for each plate compressive strength;
the second stage is the manufacturing of laminations, mechanically connected in series so that arise in the plates during acceleration mechanical stresses are added together and electrically connected in parallel so that the cumulative arising in plates electric charges;
the third stage is production of the generator in the case of a porous polymeric material, including Assembly of the working fluid from the inertial mass and the package of plates and current collectors in the body,
the party mix pressporoshka with the blowing agent for the k-th plate with a specified compressive strength ofTCWk and porosity Pkcontains a blowing agent at a concentration of Xkwt. %

whereKICob- coefficient of volumetric shrinkage of the piezoelectric materialKICob=1,455;
ρn/Ris the density of the blowing agent ρn/R=1.2 g/cm3;
ρWG- x-ray density of the piezoelectric material, ρWG=8,02 g/cm3;
ρnp- compaction, ρnp=5.2 g/cm3;
a Pkis calculated from the dependence of

whereTCW1- the compressive strength of non-porous pottery first, the most remote from the inertial mass, plate,TCW16108Pa
and acceleration at impact a=(1,3÷1,5)·106m/s2
ρ1- the density of non-porous ceramics first, Nai�more remote from the inertial mass, plate, ρ1=7,8·103kg/m3;
ρkis the density of the k-th plate,
hk- the distance between applied to the wafer conductive surfaces,
Uk- the potential difference applied between the plates of the conductive surfaces UK≈105In;

and all the data are in the worksheet, the values of the parameters in which check on the probes,
with the parameters of inertial mass is its mass M0and height h0defined

where ρ0is the density of inertial mass,
h0- the height of the inertial mass,
T33n- the compressive strength of the top plate adjacent to the inertial mass (k=n=6),
Sn- contact surface, "upper", the n-th plate.



 

Same patents:

FIELD: electricity.

SUBSTANCE: method contains connection by plains of single-domain monocrystal plates of lithium niobate or lithium tantalat such that directions of spontaneous polarisation in plates will be opposite to each other. For this preliminary polished connected surfaces of plates out of lithium niobate or lithium tantalat are cleaned such that to ensure their hydrophilic properties. Then the plates are connected by the planes, plates are compressed until disappearance of the interference rings, then they are annealed to create double-domain plate. To the opposite surfaces of the plates the electrodes are applied out of the material resistant to high temperatures.

EFFECT: possibility to ensure anhysteretic actuators with linear characteristic operable in wide range of temperatures, improved produceability.

2 cl, 5 dwg

FIELD: chemistry.

SUBSTANCE: method of obtaining a material for a high temperature mass-sensitive piezoresonance sensor based on a monocrystal of lanthanum-gallium aluminium tantalate, the composition of which corresponds to formula La3Ta0.5Ga5.5-xAlxO14, where x=0.1-0.3, characterised by the electric resistance not less than 109 Ohm at a temperature of 20-600°C, includes growing of monocrystals from a melt of oxides its component constituents in an atmosphere of an oxidiser-containing inert gas, and additional annealing in air at a temperature of 1050-1150°C for 41-43 hours.

EFFECT: increase of exploitation properties, such as the electric resistance of the material itself, increased by more than an order, and extension of the work temperature range to room temperature.

4 cl, 2 dwg, 5 tbl

FIELD: electricity.

SUBSTANCE: method includes formation of volume current leads (VCL) on contact sites of a primary converter (PC) of crystalline type by the method of thermosonic microwelding with subsequent installation of the PC onto the board of the secondary converter of microelectromechanical devices and systems (MEMS). At the same time they previously perform high-temperature assembly of the PC made of a sensitive element SE and other functional elements of MEMS, which is carried out at temperature of not more than 500°C, afterwards to volume current leads made on contact sites of the PC, made of alternating metal layers Cr - Au with thickness of not more than 0.4 mcm, current leads are welded, in the form of a wire of gold by the method of contact welding. Then the PC produced in the specified manner is connected by the produced current leads in the form of a wire by the method of contact welding to contact sites of the secondary converter (SC) of MEMS.

EFFECT: increased reliability of functioning under conditions of high complex external impact.

2 dwg

FIELD: radio engineering, communication.

SUBSTANCE: method of making surface acoustic wave resonators involves etching a quartz substrate, depositing a metal coating on the substrate, making resonator structures, mounting resonators in a housing and dry treatment in two steps, the first step involving removal of organic residues from the surface of the resonators in the plasma of a mixture of oxygen and an inert gas, the inert gas used being either helium, neon or argon, with high-frequency power density of 0.02-0.08 W/cm3 and pressure of 80-150 Pa, oxygen content of 3-15 vol. %, inert gas content of 85-97 vol. %, and the second step involving tuning the frequency of the resonators by reactive ion-beam etching in a fluorine-containing discharge.

EFFECT: longer frequency stability of surface acoustic wave resonators owing to removal of organic residues from the resonators and higher degree of purity by adding an inert gas into oxygen plasma and by tuning frequency of the resonators via reactive ion-beam etching in a fluorine-containing discharge.

3 ex, 1 tbl

FIELD: measuring equipment.

SUBSTANCE: method includes measuring the containers of free piezoelectric elements contained directly in the product and containers of piezoelectric elements partially clamped by bonding during manufacture of the product. The difference of the containers of free and tanks partially clamped piezoelectric elements is determined. According to the difference of these containers the conformance of the product to the specified parameters is determined. In particular, the difference of the containers of piezoelectric elements caused by their partial clamping at their connection to the bimorph is determined, or the difference of the containers of the piezoelectric element caused by its partial clamping at its glue joint with the mounting seat - the membrane.

EFFECT: increasing the percentage yield and reduction of the cost of the products.

3 cl

FIELD: physics.

SUBSTANCE: invention relates to making magnetoelectric converters used as a base for magnetic field sensors, microwave electronic devices, for magnetoelectric information recording technology and for electromagnetic energy and vibration energy storages. The method involves forming a stack of alternating magnetostrictor and piezoceramic layers. Said stack is formed in three steps: first, electroconductive contacts are deposited on the entire surface of magnetostrictors; all surfaces of magnetostrictors and piezoceramic, except end surfaces, are coated with a layer of electroconductive epoxy adhesive, after which a stack of alternating magnetostrictor and piezoceramic layers is formed. The layers are joined by pressing at temperature of 60-100°C and excess pressure of (1.3-2.6)·105 Pa. The multilayer ceramic heterostructure contains 9-11 magnetostrictor and piezoceramic layers. The piezoeceramic layer has thickness of 0.10-0.13 mm and the magnetostrictor layer has thickness of 0.25-0.30 mm.

EFFECT: low power consumption and high sensitivity.

2 cl, 2 tbl, 4 dwg

FIELD: chemistry.

SUBSTANCE: method of forming polydomain ferroelectric monocrystals with a charged domain wall involves using a workpiece in form of plate of ferroelectric monoaxial monocrystal of the lithium niobate and lithium tantalate family, which is cut perpendicular to the polar axis, one of the surfaces of which is irradiated with ion flux to form high concentration of point radiation defects in the surface layer, which results in high electroconductivity of the layer, after which an electric field is formed in the plate, directed along the polar axis, the polarity and value of which enable formation of domains on the surface of the plate which is not exposed, and their growth deep into the plate in the polar direction up to the boundary of the layer with high conductivity, which leads formation of a charged domain wall with an irregular shape, wherein the depth of the layer is determined by the value of the energy and dose of ions, and the shape of the wall is determined by the value of the electric field formed.

EFFECT: invention enables to form a charged domain wall, having an irregular three-dimensional shape with given geometric parameters, lying at a given depth in a monocrystalline ferroelectric plate without heating the plate or cutting a workpiece for making the plate.

4 cl, 7 dwg

FIELD: physics.

SUBSTANCE: acoustic line is made in form of a rectangular prism. Further, optically antireflecting coatings are deposited via vacuum deposition onto the faces of the rectangular prism. A first adhesive layer is then deposited on one of the faces of the rectangular prism by vacuum deposition. Using vacuum deposition, a first gold layer is deposited on said first adhesive layer. Further, a first indium layer is deposited on said first gold layer by vacuum deposition. Also, using vacuum deposition, a second adhesive layer is deposited on one of the larger faces of each of two plates made from lithium niobate of the (Y+36°)-section. Using vacuum deposition, a second gold layer is then deposited on said second adhesive layer. Using vacuum deposition, a second indium layer is deposited on said second gold layer. The acoustic line is the joined with the lithium niobate plates by pressing the lithium niobate plates with the pressure of each lithium niobate plate of the second indium layer to the corresponding first indium layer. Each of the lithium niobate plates is then ground off to the required thickness which corresponds to the operating frequency band. Using vacuum deposition, a third adhesive layer is deposited on each free large face of each lithium niobate plate. A third gold layer is then deposited on said third adhesive layer via vacuum deposition. The method is characterised by that the acoustic line material used is a TeO2 monocrystal, wherein the faces of the rectangular prism are directed perpendicular to the crystallographic direction [001], , [110], and deposition of optically antireflecting coatings is carried out on faces of the rectangular prism which are perpendicular to the the crystallographic direction ; when joining the lithium niobate plates to the acoustic line, the projections of polar axes of the lithium niobate plates are directed onto the same plates in opposite sides; the first adhesive layer is deposited on one of the faces of the rectangular prism (001); the first, second and third adhesive layers are made from chromium; said pressure lies in the range of 50-100 kg/cm2, during at least part of the time when the lithium niobate plates are pressed to acoustic line; voltage of 10-50 V is applied across each lithium niobate plate at antiresonance longitudinal vibrations of the corresponding lithium niobate plate for 1-3 minutes; the resulting workpiece, which is in form of an acoustic line with antireflection coatings, first adhesive layer, first gold layer and first indium layer lying successively on the acoustic line, and successively lying second indium layer, second gold layer, second adhesive layer of one of the lithium niobate plates and the lithium niobate plate itself, as well as the nearby successively lying second indium layer, second gold layer, second adhesive layer of another lithium niobate plate and the lithium niobate plate itself, as well as the third adhesive layer and third gold layer lying on each of said lithium niobate plates, is cut into separate elements in parallel to planes (110) of the TeO2 monocrystal.

EFFECT: high efficiency of the device while simultaneously increasing efficiency of the manufacturing process.

1 cl, 3 dwg

FIELD: physics.

SUBSTANCE: at the first stage of manufacture preparation of component parts and assemblies takes place that is manufacture of an armour ring of spring steel, of a ring nozzle with a conic external facet of a tungsten alloy, a titanium hexagonal foundation and a cup-type body with a coaxial connector or a cable. The second stage involves fixation of the assembly in the vertical axial fixture of the electroerosion wire-cutting machine-tool, making three vertical grooves in fixed positions, mounting sensor elements, press-fitting or hot shrink fit of the armour ring on the ring nozzle with piezoelectric elements, making horizontal radial sections under the armour ring for an inertial mass formation and installation and fixation of the body and connection to the outlet of the preliminary amplifier of the connector.

EFFECT: invention allows to use in the transducer various materials for the foundation and inertial masses which enables to deliver small-scale sizes combined with high sensitivity and self frequency due to addition of a preliminary amplifier to the transducer design which amplifier is connected to the sensor elements while the manufacture method proper involves a minimum quantity of operations.

5 dwg

FIELD: chemistry.

SUBSTANCE: method involves evacuation and treating substrates in oxygen-containing plasma. Substrates are treated in a plasma mixture of oxygen and inert gas containing 5-12 vol. % oxygen and 88-95 vol. % inert gas. The inert gas is helium, neon or argon and treatment is carried out at temperature in the reaction chamber equal to 80-140 Pa, radio-frequency power equal to 0.02-0.06 W/cm3 and exposure time of 3-15 minutes.

EFFECT: invention improves electrophysical parametres of piezoelectric devices owing to more complete removal of organic residue from piezoelectric substrates after different processes.

3 ex

FIELD: electricity.

SUBSTANCE: shock pick-up includes piezoelectric working medium and recording system. The working medium is made of piezoceramics with cohesion of 3-0 with maximum values of voltage index g33. At that the pick-up has an additional a resonating piezoelectric cell for calibration, which surface is coupled to the working medium surface.

EFFECT: increasing sensitivity of the piezoelectric pick-up at minimum weight, potential calibration and functional check in zero gravity conditions.

4 cl, 3 dwg, 1 tbl

FIELD: physics.

SUBSTANCE: invention relates to making magnetoelectric converters used as a base for magnetic field sensors, microwave electronic devices, for magnetoelectric information recording technology and for electromagnetic energy and vibration energy storages. The method involves forming a stack of alternating magnetostrictor and piezoceramic layers. Said stack is formed in three steps: first, electroconductive contacts are deposited on the entire surface of magnetostrictors; all surfaces of magnetostrictors and piezoceramic, except end surfaces, are coated with a layer of electroconductive epoxy adhesive, after which a stack of alternating magnetostrictor and piezoceramic layers is formed. The layers are joined by pressing at temperature of 60-100°C and excess pressure of (1.3-2.6)·105 Pa. The multilayer ceramic heterostructure contains 9-11 magnetostrictor and piezoceramic layers. The piezoeceramic layer has thickness of 0.10-0.13 mm and the magnetostrictor layer has thickness of 0.25-0.30 mm.

EFFECT: low power consumption and high sensitivity.

2 cl, 2 tbl, 4 dwg

FIELD: physics.

SUBSTANCE: piezoelectric multilayer component has a stack (1) of piezoceramic layers (2) and electrode layers (3) arranged one above the other. At least one piezoceramic layer is printed with a layer (4) structured according to a predefined configuration in a piezoelectrically inactive zone of the stack. The structured layer has at least one connecting element (4a) by which piezoceramic layers which are adjacent in the stacking direction are mechanically connected to each other with a first strength. The structured layer has interspaces (4b) filled at least in part with piezoceramic material of the adjacent piezoceramic layers. The adjacent piezoceramic layers in the interspaces are mechanically connected to each other with a second strength, which is less than the first strength.

EFFECT: longer extension and period of operation.

15 cl, 1 tbl, 4 dwg

FIELD: physics.

SUBSTANCE: acoustic line is made in form of a rectangular prism. Further, optically antireflecting coatings are deposited via vacuum deposition onto the faces of the rectangular prism. A first adhesive layer is then deposited on one of the faces of the rectangular prism by vacuum deposition. Using vacuum deposition, a first gold layer is deposited on said first adhesive layer. Further, a first indium layer is deposited on said first gold layer by vacuum deposition. Also, using vacuum deposition, a second adhesive layer is deposited on one of the larger faces of each of two plates made from lithium niobate of the (Y+36°)-section. Using vacuum deposition, a second gold layer is then deposited on said second adhesive layer. Using vacuum deposition, a second indium layer is deposited on said second gold layer. The acoustic line is the joined with the lithium niobate plates by pressing the lithium niobate plates with the pressure of each lithium niobate plate of the second indium layer to the corresponding first indium layer. Each of the lithium niobate plates is then ground off to the required thickness which corresponds to the operating frequency band. Using vacuum deposition, a third adhesive layer is deposited on each free large face of each lithium niobate plate. A third gold layer is then deposited on said third adhesive layer via vacuum deposition. The method is characterised by that the acoustic line material used is a TeO2 monocrystal, wherein the faces of the rectangular prism are directed perpendicular to the crystallographic direction [001], , [110], and deposition of optically antireflecting coatings is carried out on faces of the rectangular prism which are perpendicular to the the crystallographic direction ; when joining the lithium niobate plates to the acoustic line, the projections of polar axes of the lithium niobate plates are directed onto the same plates in opposite sides; the first adhesive layer is deposited on one of the faces of the rectangular prism (001); the first, second and third adhesive layers are made from chromium; said pressure lies in the range of 50-100 kg/cm2, during at least part of the time when the lithium niobate plates are pressed to acoustic line; voltage of 10-50 V is applied across each lithium niobate plate at antiresonance longitudinal vibrations of the corresponding lithium niobate plate for 1-3 minutes; the resulting workpiece, which is in form of an acoustic line with antireflection coatings, first adhesive layer, first gold layer and first indium layer lying successively on the acoustic line, and successively lying second indium layer, second gold layer, second adhesive layer of one of the lithium niobate plates and the lithium niobate plate itself, as well as the nearby successively lying second indium layer, second gold layer, second adhesive layer of another lithium niobate plate and the lithium niobate plate itself, as well as the third adhesive layer and third gold layer lying on each of said lithium niobate plates, is cut into separate elements in parallel to planes (110) of the TeO2 monocrystal.

EFFECT: high efficiency of the device while simultaneously increasing efficiency of the manufacturing process.

1 cl, 3 dwg

FIELD: electricity.

SUBSTANCE: piezoelectric device consists of a number of stacked layers of piezoceramic material. Each layer has two flat inner electrodes with engagement factor less than 100%; they contact in sequence with either left or right external electrodes which are located at side wall of the device. The device also contains additional uniformly distributed layers of material with high thermal conductivity, for example, aluminium nitride (AlN), beryllium oxide (BeO) or silicon carbide (SiC) or similar materials. Thickness of additional layers is not less than thickness of piezoceramic layers. Number of additional layers is determined by ratio for product of thickness, number of layers and thermal conductivity of main and additional layers.

EFFECT: reduction of inner temperature gradients, improvement of reliability and operating life.

2 cl, 1 dwg

FIELD: electricity.

SUBSTANCE: piezoelectric drive with 3D packet piezoelement for installation on basic structure has at least one surface of packet piezoelement, which is exposed to 2D or 3D profiling perpendicularly to layers of packet, and this at least one profiled surface is fit to circuit of basic structure, at which drive should be installed.

EFFECT: invention provides for high capacity of piezoelement and piezoelectric drive with simultaneous elimination of piezoelement damage risk in process of installation onto part.

17 cl, 12 dwg

FIELD: electricity.

SUBSTANCE: radiator of plane ultrasonic wave represents coaxial construction containing the set of piezoelements in the form of plane rings, which is enveloped on two sides with parts made in the form of bushes. In holes of piezoelements and bushes, along the construction axis there arranged is resonant waveguide acoustic transformer. This transformer serves as tie bar as well. At that, projection of connection of tie bar and the second bush to radiator axis includes the point belonging to the plane of equal amplitudes of coupled vibrations of itself and the construction tied with it if it can be assumed solid and when there is no that connection. Radiator can include several sets of piezoelements alternating with bushes and tied with common tie bar, which increases mechanical radiation power proportionally to the number of those sets.

EFFECT: increasing efficiency owing to decreasing energy losses in mechanical connections of its vibrating system.

1 tbl, 4 dwg

FIELD: piezoelectric drives.

SUBSTANCE: proposed piezoelectric drive characterized in high economic efficiency has housing accommodating thin-walled piezoelectric cylinder, electrodes exciting resonance-tuned bending vibrations, and at least two multilayer cylinders shielded by wear-resistant flexible shells within housing. Multilayer cylinders are assembled by inserting one into other for alternate vibration in convexo-concave manner relative to one another thereby varying cylinder-to-cylinder space filled with material in the form of liquid or air. This material in the form of liquid or air brought to water hammer condition in conjunction with hydraulic ram or supersonic air speed creates superfluidity of material in the form of liquid or air. In addition, proposed device is distinguished by high mechanical endurance at system resonance ensuring superconductivity; the latter and multilayer cylinders jointly provide for minimal voltage requirement for exciting and passing maximal current.

EFFECT: enhanced economic efficiency, ability of handling considerable forces and displacements.

2 cl, 2 dwg

FIELD: flaw inspection of rolling stock and tubes.

SUBSTANCE: ultrasonic transducer lattice has base, piezoids, grounded and pulse electrodes for connection to respective probing-pulse generators; it can be assembled, for instance, of plurality of equal-size piezoids fully insulated from one another; base is made in the form of one- or two-sided organic glass prism whose surfaces are stepped; each piezoid is glued to step parallel to other step partially overlapping the latter; idle parts of piezoids are depolarized; lattice is potted in compound; installation and overall dimensions of piezoids meet following equations: a = 1.2b to 100b, where a is piezoid length; b is piezoid thickness; d > (1 to 10)p, where d is distance between axes of piezoid effective parts; p is length of piezoid effective part; d = 0.2 to 10 mm.

EFFECT: simplified design of ultrasonic transducer lattice.

1 cl, 1 dwg

FIELD: piezoelectric electromechanical drives or packaged sensory components.

SUBSTANCE: proposed drive or sensory component has several piezoelectric ceramic layers. Electrode layer and electrical connector protruding outside are disposed between two layers whose surfaces are facing one another and directly abutting against one another. At least one of two piezoceramic layer surfaces facing one another is provided with groove to receive at least part of electrical connector.

EFFECT: enhanced precision under impact of high temperatures and heavy steady state and transient loads.

15 cl, 7 dwg

FIELD: optics.

SUBSTANCE: proposed converter designed for operation as actuating device in adaptive optical systems has multilayer stack of plates electrically connected in parallel with double-layer ferroelectric ceramic plate with diffused phase transition. One layer of double-layer plate has slot of depth equal to thickness of this layer. Axes of slots in adjacent double-layer plates are disposed in relatively perpendicular planes.

EFFECT: elongated travel distance of operating element, enhanced time and temperature stability.

1 cl, 2 dwg

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