179 results about "Elasticity coefficient" patented technology

The invention discloses an elastically-driven modular joint with force feedback control. comprising assembly components such as a motor stator, a motor rotor, a harmonic speed reducer and the like, so that the design flexibility and compactedness of the joint can be increased; and due to the design of an air routing shaft, the joint is convenient to route, so that the joint is more succinct, the moving range of the joint can be preferably enlarged, and the running reliability of the joint can be improved. Due to the introduction of a first absolute type angle sensor and a second absolute type angle sensor, the angle deviation between an output shaft and an output end cover can be obtained, and the angle deviation is multiplied by the elasticity coefficient of an elastic torsion spring, so that a moment value applicable to the joint can be obtained, for an input feedback value of a joint signal; and a reliable moment feedback signal can be provided for the joint, so that the elastic torsion spring can be deformed, the smoothness can be provided for the joint, and an energy storing mechanism can be further provided for the joint, and the elastically-driven modular joint is applicable to a robot, so that the interaction capability between the robot and the environment can be enhanced, and the running efficiency of the robot can be improved.

The invention provides a device and method for detecting the interior initial stress of a steel structural member based on the ultrasonic method. According to the method for detecting the interior initial stress of the steel structural member based on the ultrasonic method, the interior initial stress sigma of the steel structural member is solved by firstly calibrating the acoustic elasticity coefficient B of the fixed sonic path distance of a replica of the steel structural member in service and then detecting the change of the acoustic time t of ultrasonic waves in the steel structural member in service. An existing method for nondestructive detection of the stress of a steel structural member mainly has the disadvantages that only the change of the stress can be detected, and the intensity of the stress in the current state can not be detected; only the stress of the positions located on the surface of the steel structural member and the stress of the positions at most dozens of microns below the surface of the steel structural member can be detected, and the intensity of the stress of positions with depths of several millimeters can not be detected. The method for detecting the interior initial stress of the steel structural member based on the ultrasonic method can overcome the defects of the existing method and can be used for nondestructive detection of the interior initial stress of various steel structural members. Detections results are verified, the precision is high, the error requirement of practical engineering can be met, and the structural member can not be damaged during detection.

The present invention is an apparatus, method and system for determining the coefficient of elasticity of a target by detecting determining simultaneously two or more critical-angle reflections of an ultrasound wave from the target using an ultrasound transducer that includes a transmitter and two or more receivers and calculating the elasticity coefficients of the target.

The present invention reduces exhaust emissions at startup, provides improved fuel pressure control performance in a low-load region, and detects high-pressure fuel system abnormalities. Disclosed is a high-pressure fuel system control device which includes a high-pressure pump for pressurizing fuel and discharging the pressurized fuel to a fuel rail, an injector for injecting the fuel stored in the fuel rail, and a fuel pressure sensor for measuring the pressure of the fuel stored in the fuel rail, and controls the high-pressure pump and the injector in accordance with an output generated from the fuel pressure sensor. The high-pressure fuel system control device includes a homo-elasticity coefficient estimation section for estimating a homo-elasticity coefficient of fuel in accordance with a pressure change which occurs when a fuel discharge amount of the high-pressure pump is not smaller than a predetermined value; a fuel pressure estimation section for estimating fuel pressure within the fuel rail in accordance with the homo-elasticity coefficient and control target values for the high-pressure pump and the injector; and a fuel control section for correcting an injection pulse of the injector in accordance with the fuel pressure estimated by the fuel pressure estimation section.

A liquid crystal display includes a first substrate having a display area and a peripheral area and including a plurality of pixels formed in the display area, a second substrate facing the first substrate, and a plurality of first groups of bead spacers and a plurality of second groups of bead spacers disposed between the first substrate and the second substrate. The first groups of bead spacers have a different size or different elasticity coefficient than the second groups of bead spacers, and include a plurality of bead spacers, respectively.

The invention provides an AFM (Atomic Force Microscope)-based device and method for performing nanoindentation measurement on the surface of a microparticle. The device is composed of an AFM system, a sheet-shaped plane for holding a sample to be measured is arranged on a sample platform at the top of a scanatron, a double faced adhesive tape for sticking and fixing the sample to be measured is arranged on the sheet-shaped plane, and a nanoindentation needle tip for scanning and nanoindentation operation is fixed in a needle tip holder and arranged above the sample to be measured. When the device is in use, the sample to be measured is adhered to the sheet-shaped plane with the double faced adhesive tape; the sheet-shaped plane is placed on the sample platform at the top of the scanatron; and then the nanoindentation needle tip fixed in the needle tip holder performs scanning and nanoindentation operation above the sample to be measured, wherein the nanoindentation needle tip is a diamond needle tip and has an elasticity coefficient remained between 100N / m and 300N / m and an resonance frequency of 35-65khz. According to the invention, nanoindentation measurement is successfully carried on the surface of a detected powdery microparticle sample with the particle size of 20-80 micrometers.

An ultrasonic method for measuring residual stress of a cambered workpiece comprises the following steps: S1, performing stress testing to obtain a function curve t0x=M (x) between a propagation distance x and the propagation time t0x of a longitudinal critical refraction wave in a zero-stress plate calibration block; S2, performing stress testing to obtain a function curve Kx=F (x) of a nominal acoustic elasticity coefficient Kx corresponding to the propagation distance x; S3, measuring the propagation time t of the longitudinal critical refraction wave in a cambered workpiece; S4, measuring a propagation distance a of the longitudinal critical refraction wave in the cambered workpiece; S5, according to the function curve t0x=M (x) and the function curve Kx=F (x), obtaining the propagation time t0a and a nominal acoustic elasticity coefficient Ka corresponding to the propagation distance a in a zero-stress state, and then according to a formula sigma=K (t-t0), working out the residual stress of the cambered workpiece to be measured. By the ultrasonic method, the residual stress of the cambered workpiece can be measured conveniently and fast; meanwhile, the problem that in the prior art, calibration is inaccurate is solved, so that the ultrasonic measurement accuracy of the residual stress of the cambered workpiece is greatly improved.

This invention discloses one kind of standing erect washer suspension unit, by the go-between, the shock absorber wrap, reduces inspires the circle, above two pendulum spring, at least an anchor constitution, a go-between end fixes in the position which the washer does not revolve, the shock absorber method on the go-between, and fixes in the spot which in the washer revolves, the go-between fixes and inserts in the shock absorber set, reduces inspires the circle cirumferential surface and a shock absorber set of in week surface contact, reduces inspires the circle when washes clothes the barrel position variation to have the friction force to do reduces inspires the function, is pendulum spring pocket outside the go-between, is located reduces inspires the circle and between the shock absorber set. In order to fixedly hanging on the go-between spring position, in pendulum spring side and the breast forms the anchor. In order to define forms has the anchor to be hanging the spring free migration distance, lengthens the anchor in a shock absorber set of center which forms to hang the end. The washer when washes and the dehydration, is pendulum spring by the different elasticity coefficient work, can fully reduce the vibration which exerts from exterior.

The present invention reduces exhaust emissions at startup, provides improved fuel pressure control performance in a low-load region, and detects high-pressure fuel system abnormalities. Disclosed is a high-pressure fuel system control device which includes a high-pressure pump for pressurizing fuel and discharging the pressurized fuel to a fuel rail, an injector for injecting the fuel stored in the fuel rail, and a fuel pressure sensor for measuring the pressure of the fuel stored in the fuel rail, and controls the high-pressure pump and the injector in accordance with an output generated from the fuel pressure sensor. The high-pressure fuel system control device includes a homo-elasticity coefficient estimation section for estimating a homo-elasticity coefficient of fuel in accordance with a pressure change which occurs when a fuel discharge amount of the high-pressure pump is not smaller than a predetermined value; a fuel pressure estimation section for estimating fuel pressure within the fuel rail in accordance with the homo-elasticity coefficient and control target values for the high-pressure pump and the injector; and a fuel control section for correcting an injection pulse of the injector in accordance with the fuel pressure estimated by the fuel pressure estimation section.

The invention discloses a design method of a two-degree-of-freedom piezoelectric vibrator for realizing broadband response. The method comprises the following steps of: step 1, respectively taking upper and lower limits of a prospective frequency band as inherent frequency initial values of two single-degree-of-freedom cantilever beams, and determining the elasticity coefficients k1 and k2 of thetwo single-degree-of-freedom cantilever beams and the masses m1 and m2 of two single-degree-of-freedom cantilever beam piezoelectric vibrators; step 2, determining the initial value of the elasticitycoefficient k3 of a connection spring according to the prospective ratio of the first order resonance frequency to the second order resonance frequency of the two-degree-of-freedom vibrator; step 3, based on above parameters, establishing a finite element model of the two-degree-of-freedom piezoelectric vibrator, under constraints of frequency band, structure size and material characteristics, for the aim of realizing maximum output power, regulating four parameters including thickness of a piezoelectric layer, thickness of the cantilever beams, size of mass blocks and elasticity coefficient of the connection spring. The method realizes the broadband response of the two-degree-of-freedom piezoelectric vibrator under the premise of keeping high-efficiency energy conversion.

The invention discloses a method for modeling and simulating a door lock system based on vehicle crash safety. The method comprises the following steps of: A, preliminarily modeling the door lock system: performing geometry processing modeling and meshing on the door lock system, and exerting a motion relation restraint on components of the door lock system; B, simulating a pull rope mechanism: simulating the pull rope mechanism by using a mechanism with an equivalent synthesized spring and deducing expressions of an initial torque and an elasticity coefficient of the equivalent synthesized spring; C, inputting parameter information into the door lock system, wherein the parameter information comprises spring information, material information of the system components and quality information of the system components; and D, transferring the current door lock system model into a whole vehicle crash finite element calculation model and performing crash simulation calculation, and determining the crash safety performance of the door lock system by analyzing a simulation result. By the method, mechanism motion and component deformation of the door lock system at the moment of vehicle crash can be simulated precisely, so that the crash safety performance can be evaluated and analyzed accurately, the product design period can be shortened and the experimental cost is saved; therefore, the practicability is high.

The invention relates to a method for improving surface stress sensitivity of a resonant ultrathin cantilever beam sensor, and belongs to the technical field of micro-mechanical sensing. The method is particularly characterized in that self-assembling monomolecular sensitive films capable of identifying selection specificity can be grown on the upper surface and the lower surface of an ultrathin resonant cantilever beam sensor; after specificities of sensitive molecules and target molecules to be detected are combined, interaction among the target molecules generates surface stress on the surfaces of the cantilever beam; and the combined action of the upper surface stress and the lower surface stress causes change of elasticity coefficient of the cantilever beam so as to change inherent resonance frequency of the cantilever beam, and achieve detection for the target molecules through measuring the change of the resonance frequency. Compared with the prior method for sensitivity test by using a mass adsorption method, the method for improving the surface stress sensitivity can carry out biochemical trace test, and the sensitivity can be improved by one order of magnitude. The method has the characteristics of simple principle, high sensitivity and easy realization.

The invention discloses a crank torsion sensing device and a crank torsion detection method. The crank torsion sensing device is arranged at a five-way shaft of a power-assisted electric vehicle; a backward pull is generated at the pivot of the five-way shaft through a reacting force borne by a chain driven by a big fluted disc when a pedal is treaded, and the torsion value generated when the pedal is treaded can be acquired by measuring the magnitude of the backward pull; and the magnitude of the backward pull borne by the five-way shaft is acquired on the basis of the similar principle of a spring platform scale, by measuring the displacement of the five-way shaft and according to the set elasticity coefficient and the deformation of a spring. The displacement generated by the five-way shaft due to stress enables a detector to generate a voltage or current signal, the electric signal is used as a sensing control signal, and the control signal can determine the magnitude of the driving power, so that the purpose of power-assisted drive is fulfilled.

The invention discloses the package structure, comprising the first cushion material and the second cushion material. The first cushion material possesses the first contact surface, and the second cushion material possesses the second contact surface. The first contact surface and the second contact surface are used to contact articles. The first contact surface is exposed out of the second contact surface, and the second contact surface is projected out of the first contact surface. The first cushion material possesses the first elasticity coefficient and the first damper coefficient. The second cushion material possesses the second elasticity coefficient and the second damper coefficient. The first elasticity coefficient is the same with second elasticity coefficient, and the damper coefficient is different from the second damper coefficient.

The invention provides a bolt fastening force ultrasonic detection and key detection parameter determination method based on finite elements. The method is suitable for bolting force ultrasonic soundtime nondestructive measurement. The finite element theory and the acoustic elasticity principle are combined, and a bolt fastening force ultrasonic detection principle model is established. A bolt finite element model and a static simulation are established, the bolt axial stress distribution rule on the ultrasonic propagation path is obtained, so that the shape factor of the bolt is determined.The ultrasonic detection coefficient of the bolt fastening force is calculated by combining the acoustic elasticity coefficient of the bolt material measured by the critical refraction longitudinal wave. The method is low in cost and good in adaptability, and the detection coefficient can be accurately and quickly determined.

A liquid crystal display includes a first substrate having a display area and a peripheral area and including a plurality of pixels formed in the display area, a second substrate facing the first substrate, and a plurality of first groups of bead spacers and a plurality of second groups of bead spacers disposed between the first substrate and the second substrate. The first groups of bead spacers have a different size or different elasticity coefficient than the second groups of bead spacers, and include a plurality of bead spacers, respectively.

The present invention relates to a system and method for the system and method for modeling demand by consumer segments. In some embodiments a segment data organizer may receive transaction data. Transaction data may include transaction logs (T logs) from point of sales records from a retailer. These transaction logs, for the most part, include identification information for each transaction. The segment data organizer may also receive customer identification data which includes groupings of customers by consumer segments. The identification information within the transaction logs may be cross referenced by the customer identification data in order to generate groupings of transactions belonging to consumers in each segment. The organizer may then also aggregate the transaction logs by location, time series and product. The aggregated data may be supplied to an econometric engine capable of generating elasticity coefficients for each set of aggregate data. These coefficients may be stored or utilized to generate optimized pricing, lifts, and demand models.

The present invention relates to a variable-area capacitor for a micromechanical sensor, a micromechanical comb grid capacitor accelerometer and a micromechanical comb grid capacitor gyroscope. Among them, the variable-area capacitor structure comprises of a movable and a fixed electrodes in each capacitor unit; a front surface of aforesaid movable electrode is parallel to that of aforesaid fixed electrode; the front surface of aforesaid movable electrode is in a rectangular shape, and the front surface of the fixed electrode is in a triangular or sawteeth shape or the front surface of the movable electrode is in a triangular or sawteeth shape, and the front surface of the fixed electrode is in a rectangular form; the triangular front surface is only overlapped with one long side of aforesaid rectangular front surface. Micromechanical sensors with variable-area capacitor structures of the invention can adjust elasticity coefficient as compared with present technology.

The invention provides a device for analyzing cardiovascular and cerebrovascular characteristics and blood characteristics and a detecting method, belonging to the field of medical equipment. The device comprises a pressure pulse wave sensor, a carotid artery and vertebral artery rheogram inductance electrode, an electrocardiogram inductance electrode, a cardiophonogram sensor, a signal receiver, a main processor and an in-out part. The device can realize the cardiovascular and cerebrovascular noninvasive detection, and biomechanically analyzes each branched blood vessel of the cardiovascular and cerebrovascular system by measuring the blood pressure and the blood flow volume of a left cervical vertebra artery, a right cervical vertebra artery, a cerebrum front artery, a cerebrum middle artery, a cerebrum back artery, a left coronary artery and a right coronary artery, obtains biomechanics indexes such as the elasticity coefficient, the compliance, the blood resistance, the blood flow volume and the like of each branched blood vessel of the cardial blood vessel and the brain blood vessel, has an important significance for the early diagnosis of the myocardial infarction and the cerebral thrombosis by taking as equipment for the cardiography, the magnatic resonance imaging MRI, the CT and the like and supplementary equipment between the TCD and the ECG.

The invention provides a liquid crystal compound and a preparation method thereof as well as a liquid crystal mixture containing the liquid crystal compound and an application of the liquid crystal mixture. The liquid crystal compound has a general formula I as shown in the specification, wherein R1 and R2 are independently selected from one of H, alkyl with 1 to 15 carbon atoms, halogenated alkyl, alkoxy and alkenyl, one or more CH2 radicals in R1 and R2 can be independently substituted by -O-, -S- or -Cis equivalent toC-, and any adjacent two CH2 radicals can not be substituted by -O-O-; n1, n2, n3 and n4 are independently selected from 0 or 1, and at least one of n1 and n4 is 1; any one of X1, X2, X3 and X4 is F, and the others are H. The liquid crystal compound has good chemical, thermal and light stabilities; the addition of cyclopentyl can improve the ratio of a macroaxis to a brachyaxis of the liquid crystal compound and the value of degree of order S of the liquid crystal compound to ensure that the liquid crystal compound has a nematic phase with a wide temperature range and a high elasticity coefficient K.

The invention discloses a multi-elasticity quantitative segmentation method for driving factors influencing runoff changes. The method comprises the following steps: collecting long-term hydro-meteorological data of a river basin; calculating potential evaporation amount and actual evaporation amount; then calculating parameters representing basin characteristics by using a single-parameter Budyko equation; analyzing the change extent of each hydro-meteorological variable of the basin relative to a long-time average annual value; calculating the elasticity of runoff relative to seven driving factors; determining the abrupt change point of annual runoff process, wherein a period before the abrupt change point is a reference period and a period after the abrupt change point is a changing period; and analyzing the contribution rates of the seven driving factors to the runoff changes based on the elasticity coefficients of the hydro-meteorological variables and the differences of the hydro-meteorological variables in the changing period relative to the hydro-meteorological variables in the reference period. According to the invention, a climate elasticity process is applied to multi-elasticity analysis of the influence of rainfall, highest temperature, lowest temperature, wind speed, sunlight, relative humidity and basin characteristics on runoff changes based on the changes of hydro-meteorological elements of the basin, so the influence of each driving factor on the runoff changes is quantitatively identified. The method has good applicability and is more comprehensive and more scientific in calculated results.

A measurement apparatus includes a workbench, a loading mechanism fixed to the workbench, a deformation measuring mechanism, and a stress meter. The deformation measuring mechanism includes a slide beam, and a displacement meter. The loading mechanism includes a guiding shaft extending through a to-be-tested coil spring. A measuring pole of the stress meter, the sliding beam, and the guiding shaft are coaxial. Opposite ends of the coil spring are respectively abutted the slide beam and the loading mechanism. A measuring pole of the displacement meter is connected to the sliding beam. When the stress meter slides towards the slide beam, the displacement of the detecting pole of the displacement member is equal to a change of a length of the coil spring, and recorded by the displacement meter, and a value of a force applied to the coil spring is recorded by the stress meter.

The invention discloses a correcting method for evaluating material stress by influencing ultrasonic waves through grain sizes, and belongs to the technical field of ultrasonic harmless evaluation. According to the method, on the basis of energy attenuation analysis of ultrasonic waves in samples, a dual-ultrasonic probe constant in transmission distance is prepared, samples of different grain sizes are obtained through a heat treatment method, and the relation between the time difference of ultrasonic signals of the samples of different grain sizes and the stress is calculated and established through an ultrasonic acoustic elasticity coefficient calibration experiment, ultrasonic acoustic elasticity coefficients of the samples of different grain sizes are obtained through a linear fitting function, the function between the ultrasonic acoustic elasticity coefficients and the grain sizes is obtained through power function fitting, and correction for evaluating material stress by influencing ultrasonic waves through grain sizes is achieved. The harmless method is provided for evaluating material stress influenced by grain sizes and has the advantages of being rapid, convenient to implement, safe, capable of achieving online evaluation and the like.

The invention discloses a method for calculating plane wave reflection coefficients in an elastic multi-layered medium. The method comprises the following steps: (1) if plane harmonic waves enter into a target layer series from a medium n+1, generating reflected longitudinal waves and reflected transverse waves in the n+1 medium, generating transmitted longitudinal waves and transmitted transverse waves in a medium 1, and writing each medium layer in a scalar potential form and a vector potential form; (2) determining relation among the displacement, stress and bit shift; (3) loading the scalar potential and vector potential of the step (1) into the step (2) to obtain a displacement and stress relation expression between the (n+1)th layer and the first layer; and (4) obtaining a displacement and stress transfer matrix containing elasticity coefficients of each layer according to the displacement and stress relation expression, which is obtained in the steps (3), between the (n+1)th layer and the first layer, solving, and obtaining reflection and transmission coefficients. According to the method, the influence of multiple waves and transformed waves of the elastic layer series as well as thickness and frequency on the reflection coefficient is considered fully, so that the method is applicable to thin-layer AVO (Amplitude Variation with Offset) analytical simulation and is high in calculation efficiency.

To provide a method of measuring the viscoelasticity coefficients of a material and a device for the viscoelasticity coefficients of a material with which it is possible to represent information of the viscoelasticity of an adsorbent material with coefficients G and G which are typically used in representing viscoelasticity, and with which it is further possible to compute the viscoelasticity coefficients in real time. In a system wherein a material is adsorbed and a film formed, either upon the surface of a piezoelectric element in solution, or on a film which is fixed upon the piezoelectric element in solution, using at least two of N overtones of the piezoelectric element, and for each N overtone, employing at least two of the resonant frequency FS and half-value frequencies F1, F2 (where F2 > F1) having half the conductance value of the conductance value of the resonant frequency, the mass load term, the viscoelasticity term, the viscoelasticity term, and the viscoelasticity term are computed, and the viscoelasticity coefficients G (stored modulus portion) and G (loss modulus portion) of the film are computed.

The invention discloses a manual spring tension and compression testing machine which aims to solve the problems that spring elasticity coefficients are detected by special equipment mostly made of electronic components currently and the special equipment is not applicable to field operation and the like. The manual spring tension and compression testing machine comprises a frame, a measuring mechanism, a transmission mechanism and a tension and compression clamp mechanism. The measuring mechanism comprises a wide-range vernier caliper (12), a small-range vernier caliper (16) and a spring (5). The spring (5) is sleeved on an upper pressing plate guide rod (3), the upper end of the spring (5) is fixed with a middle crossbeam (6), the lower end of the spring (5) is fixed with an upper spring pressing plate (15) of the tension and compression clamp mechanism, an upper measuring jaw of the small-range vernier caliper (16) is fixed with the middle crossbeam (6), a lower measuring jaw of the small-range vernier caliper (16) is fixed with the lower surface of the upper spring pressing plate (15), an upper measuring jaw of the wide-range vernier caliper (12) is fixed with the upper surface of an upper crossbeam (10), and a lower measuring jaw of the wide-range vernier caliper (12) is fixed with the lower surface of the upper spring pressing plate (15).

[Problem] To provide a dicing sheet with a protective film forming layer, provided with a precut and hardened protective film forming layer, wherein when the dicing sheet is fabricated, the protective film forming layer is not deformed even when subjected to die punch processing using a die cutter. [Solution] This dicing sheet with a protective film forming layer (10) is characterized in that a hardened protective film forming layer (4) is temporarily affixed, so as to be peelable, to the inner circumference of a support body (3) having an adhesive section on the outer circumference thereof, and the storage elasticity coefficient of the protective film forming layer at 23°C prior to hardening is 0.6-2.5 GPa.

The invention provides an oil-gas spring, a wheel steering mechanism provided with the oil-gas spring, a wheel provided with the oil-gas spring and a vehicle adopting the wheel. The oil-gas spring comprises an oil cylinder, an elastic damping unit and an oil path unit, wherein the oil cylinder comprises a piston rod and multiple stages of cylinder barrels nested stage by stage; an annular oil chamber is formed between every two adjacent stages of cylinder barrels in a surrounding mode, the piston rod is embedded and slidably arranged in the innermost cylinder barrel, and the piston rod and theinner wall of the innermost layer cylinder barrel form an annular oil chamber in a surrounding mode; and an elastic damping port is formed in the upper part of the outermost cylinder barrel, the upper part of the outermost cylinder barrel is connected with the elastic damping unit, oil path ports are formed in the upper part of the outermost cylinder barrel and all the annular oil chambers, and each oil path port is connected with the oil path unit. According to the oil-gas spring, the wheel, the vehicle and the like, the position height of each wheel center, the size of the moving stroke andthe size of the elasticity coefficient can be adjusted according to the needs of various driving conditions so that the requirements of different driving conditions can be met, and the advantages ofbeing high in trafficability and high in maneuverability are provided.

A multi-combinational spring mattress includes a frame portion for enclosing and defining a containing space, a bottom layer having a plurality of linear ditches longitudinally and latitudinally intersected at the top of the bottom layer, a plurality of lumps formed among the ditches, and the bottom layer being disposed at the bottom of the containing space, a plurality of spring layers, each having a plurality of individual spring cylinders and stacked onto the top of the bottom layer, a surface layer stacked onto the top of the spring layers, and a wrapping cover for completely wrapping the frame portion, the bottom layer, the spring layers and the surface layer in the wrapping cover, and the spring layers have elasticity coefficients, so that users can change the configuration of the spring mattress or replace any damaged or elastically fatigue spring layer easily.