CN105785263A - Method and device for detecting switching value of pressure switch - Google Patents

Abstract

The invention provides a method and a device for detecting the switching value of a pressure switch. The device comprises a pressure generator communicated with a pressure switch through a pressure pipe, a pressure control element, a pressure sensor, and a controller provided with a data processing unit, wherein the pressure sensor is installed on the pressure pipe and electrically connected with the controller, the pressure control element is electrically connected with the pressure generator to control the pressure generator, and the pressure control element is electrically connected with the controller. According to the invention, pressure change of the pressure pipe is transmitted via the pressure sensor to the controller in real time, the data processing unit arranged in the controller acquires the pressure change value and generates a control instruction according to preset change rules of pressure, and the pressure generator changes the pressure in the pipe under control of the pressure control element. By adopting the device and the method provided by the invention, the switching value of a pressure switch can be detected, quick detection is realized, the accuracy of detection is improved, the repeatability of detection results is good, the labor cost is reduced, and work is reliable.

Description

The method of detection pressure switch switching value and device

Technical field

The invention belongs to pressure sensing arts, be specifically related to a kind of device detecting pressure switch switching value and utilize the detection method of this device.

Background technology

Pressure switch is a kind of conventional pressure control device, and when input pressure reaches (being raised or lowered to) predetermined value, the state of switching on-off switches, to send alarm or control signal.Force value when pressure switch switches is called pressure switch switching value, including upper switching value and lower switching value.Control the start and stop of pressure-generating device or the opening and closing of supercharging, air relief valve by pressure switch, the force value of pressure system can be controlled within limits.In the pressure control procedure of industrial circle, the accuracy of detection of pressure switch switching value directly affects pressure controling precision, therefore needs before use pressure switch is verified, and detects pressure switch switching value.

Common pressure switch has mechanical type, the big class of electronic type two.Pressure is converted to the signal of telecommunication by the pressure element of electronic pressure switch, digital quantity is become after signal conditioning circuit, A/D conversion, obtaining force value after treated device computing, force value is carried out driving switch element (such as mechanical relay, electronic switching element etc.) compared with user's setting value and is switched on or switched off by simultaneous processor；Pressure is converted to deformation by the pressure element (diaphragm, corrugated tube, piston etc.) of mechanical pressure switch, through mechanical mechanism relatively after promote the on off operating mode of switch element.Usual pressure switch all has pipeline input interface end and output switch parameter interface end, wherein pipeline input interface end can connect fluid pressure line or pneumatic circuit, path is formed with ambient pressure pipeline, the switching value (containing break-make output type, level output type, amount of logic output type etc.) of output switch parameter interface end output pressure switch contact action, for the control unit in access industrial control system for Stress control.

Pressure source 100, standard pressure gauge 101 and pressure switch 103 are connected formation path by isobaric pipeline 102 by existing pressure switch detection system (such as shown in Fig. 4), on off state acquiring unit 104 is connected in pressure switch 103, measures the break-make of pressure switch 103 contact.Pressure source 100 is slowly boosting to pressure switch 103 and is reducing pressure, this process generally adopts the method for artificial listening reading to measure, also useful circuit tester measurement switches on-off the change judging switch, data also accurately and are in time read while needing operator to judge switch change in operation, in this process inevitably free on delay, there is bigger error with actual value in the numerical value causing reading, is also easy to the phenomenon occurring misreading, judge by accident；Speed because boosting when manually reading, operate or reducing pressure is inconsistent and causes that each testing result is inconsistent, poor repeatability；And in above-mentioned pressure switch detection system, pressure source 100 gives the process that pressure switch 103 is slowly boosted and reduced pressure comparatively time-consuming.

Summary of the invention

In order to solve the problems referred to above, one aspect of the present invention purpose is in that to provide the device of a kind of detection pressure switch switching value that switching value detects, reproducible, accuracy is high, easy to use that can be rapidly completed pressure switch.

The above-mentioned purpose of the present invention is realized by techniques below scheme:

A kind of device detecting pressure switch switching value, including the pressure generator connected with pressure switch by pressure piping, also include pressure control valve, pressure transducer and the controller being provided with data processing unit, pressure transducer is installed on pressure piping and is electrically connected with the controller, pressure control valve electrically connects with pressure generator and is used for controlling pressure generator, pressure control valve is electrically connected with the controller, the data processing unit of described controller is analyzed processing and producing corresponding control instruction to obtain data with described pressure transducer and pressure switch electrical connection, pressure generator is sent to via pressure control valve.

In the device of above-mentioned detection pressure switch switching value, described controller also includes memory element, and memory element electrically connects and carry out data interaction with pressure control valve, pressure transducer, and has and carry out the interface of data interaction with data processing unit.

The device of above-mentioned detection pressure switch switching value also includes the electrical interface electrically connected with described controller, and described electrical interface is the integrated component being provided with multiple interfaces, including switch numbers amount interface, USB interface, serial ports, wave point and Ethernet interface.

The device of above-mentioned detection pressure switch switching value also includes the external equipment being connected to described controller, and described external equipment includes computer, LCDs or touch screen.

The purpose of another aspect of the present invention is in that the method providing detection pressure switch switching value, and the method utilizes the device of described detection pressure switch switching value to carry out the detection of pressure switch switching value, comprises the following steps:

Initial value obtaining step, the data processing unit of described controller by pressure transducer obtain described pressure switch in boost process state switching time force value as on switching value initial value R₀And the rate of pressure rise of correspondence is as rate of pressure rise initial value v₁₀, or force value when pressure switch state switches in pressure reduction is as lower switching value initial value F₀And the rate of pressure reduction of correspondence is as rate of pressure reduction initial value v₂₀；

Detected value obtaining step, data processing unit transmits the instruction adjusting pressure size in pressure piping (boosting or blood pressure lowering) by described pressure control valve to pressure generator, by pressure transducer obtain described pressure switch in boost process force value during state switching as on switching value detected value R_iAnd the rate of pressure rise v of correspondence_1i, or force value when state switches in pressure reduction is as lower switching value detected value F_iAnd the rate of pressure reduction v of correspondence_2i, wherein, i=1,2,3...；

Judge step, difference between the upper switching value detected value of what nearest twice or more than twice was got by data processing unit include upper switching value initial value or the maxima and minima in including the lower switching value detected value of lower switching value initial value compares with ormal weight δ, when described difference is more than or equal to described ormal weight δ, return described detected value obtaining step；When described difference is less than described ormal weight δ, described upper switching value detected value or lower switching value detected value that the last time is obtained by data processing unit export as upper switching value or the lower switching value of described pressure switch.

In the method for above-mentioned detection pressure switch switching value, controller also includes memory element, memory element electrically connects with pressure control valve, pressure transducer and carries out data interaction, and have and carry out the interface of data interaction with data processing unit, data processing unit and memory element carry out data interaction.

In the method for above-mentioned detection pressure switch switching value, described detecting device also includes the electrical interface electrically connected with described controller, and described pressure switch transmits pressure switch by this electrical interface to controller and switches the signal of action.

In the method for above-mentioned detection pressure switch switching value, described detecting device also includes external equipment, described external equipment is connected to described controller by electrical interface, described electrical interface is the integrated component being provided with multiple interfaces, including switch numbers amount interface, USB interface, serial ports, wave point and Ethernet interface, described external equipment can be one or more in computer, LCDs and touch screen.

More specifically, the method detecting pressure switch switching value includes two schemes:

Scheme one

In existing pressure switch detection system shown in Fig. 4, pressure source 100 is slowly boosting to pressure switch 103 and is reducing pressure, this process generally adopts the method for artificial listening reading to measure, also useful circuit tester measurement switches on-off the change judging switch, data also accurately and are in time read while needing operator to judge switch change in operation, in this process inevitably free on delay, there is bigger error with actual value in the numerical value causing reading, is also easy to the phenomenon occurring misreading, judge by accident；Speed because boosting when manually reading, operate or reducing pressure is inconsistent and causes that each testing result is inconsistent, poor repeatability.

In the pressure switch switching value detection method that existing code is previously mentioned, it does not have pressure change rate when switching value is detected makes quantitative requirement, only describe with " slowly ", it is difficult to ensure that the concordance of testing result and accuracy；And in existing method, it is generally required to specify the general scope of switching value.

First " embodiment 1 " of scheme one be to solve the problems referred to above, it is provided that the method for the detection pressure switch switching value that a kind of accuracy is high, reproducible, easy to use, and the method comprises the following steps:

Initial value obtaining step, obtain described pressure switch in boost process state switching time force value as on switching value initial value R₀And the rate of pressure rise of correspondence is as rate of pressure rise initial value v₁₀, or force value when pressure switch state switches in pressure reduction is as lower switching value initial value F₀And the rate of pressure reduction of correspondence is as rate of pressure reduction initial value v₂₀；

Detected value obtaining step, with meet this pressure switch state switching time rate of pressure rise or rate of pressure reduction compared with last time pressure switch state switching time rate of pressure rise v_1(i-1)Or rate of pressure reduction v_2(i-1)Little mode obtain described pressure switch in boost process state switching time force value as on switching value detected value R_iAnd the rate of pressure rise v of correspondence_1i, or force value when state switches in pressure reduction is as lower switching value detected value F_iAnd the rate of pressure reduction v of correspondence_2i, wherein, i=1,2,3...；

Judge step, the difference between maxima and minima in the upper switching value detected value including upper switching value initial value got nearest twice or more than twice or the lower switching value detected value including lower switching value initial value and ormal weight δ compare, when described difference is more than or equal to described ormal weight δ, return described detected value obtaining step；When described difference is less than described ormal weight δ, the described upper switching value detected value obtain the last time or lower switching value detected value are as the upper switching value of described pressure switch or lower switching value.

Rate of pressure rise v in the detected value obtaining step of such scheme one, during by rate of pressure rise or rate of pressure reduction compared with pressure switch state switching last time_1(i-1)Or rate of pressure reduction v_2(i-1)Reduce, change pressure described pipeline in plus a speed adjustment amount by pressure control valve and pressure generator with the rate of pressure rise after this reduction or rate of pressure reduction；And the upper switching value detected value including upper switching value initial value that obtained close to last time along with the force value in pressure piping of speed adjustment amount or the lower switching value detected value that includes lower switching value initial value and diminish；Concrete,

Boost process speed adjustment amount is the function of pipeline inner pressure value, and described function representation is Δ V_ij=k (R_i-1-p_j), rate of pressure rise is expressed as V_ij=θ v_1(i-1)+ΔV_ij, wherein, Δ V_ijIt is that the jth in the i-th detected value obtaining step detects the speed adjustment amount walked, V_ijIt is the rate of pressure rise in the i-th detected value obtaining step, v_1(i-1)Rate of pressure rise when being obtain upper switching value detected value in (i-1) detected value obtaining step, R_i-1For the upper switching value detected value detected in (i-1) detected value obtaining step, p_jFor the force value in the described jth detected pressure piping of detection step, k is pressure regulation, and θ is speed regulation, and meets k >=0,0 < θ < 1, i=1,2,3 ..., j=1,2,3 ...；As k=0, rate of pressure rise is expressed as V_i=θ v_1(i-1)(referring to embodiment 1: constant speed pressure control method).

Pressure reduction speed adjustment amount is the function of pipeline inner pressure value, and described function representation is Δ V_ij=k (p_j-F_i-1), described rate of pressure reduction is expressed as V_ij=θ v_2(i-1)+ΔV_ij, wherein, Δ V_ijIt is that the jth in the i-th detected value obtaining step detects the speed adjustment amount walked, V_ijIt is the rate of pressure reduction in the i-th detected value obtaining step, v_2(i-1)Rate of pressure reduction when being obtain lower switching value detected value in (i-1) detected value obtaining step, F_i-1For the lower switching value detected value detected in (i-1) detected value obtaining step, p_jFor the force value in the described jth detected pressure piping of detection step, k is pressure regulation, and θ is speed regulation, and meets k >=0,0 < θ < 1, i=1,2,3 ..., j=1,2,3 ...；As k=0, rate of pressure reduction is expressed as V_i=θ v_2(i-1)(referring to embodiment 1: constant speed pressure control method).

The detection method that embodiment 1 provides can solve accuracy and repeatability problem.

Additionally, in prior art pressure switch detection system as shown in Figure 3, there is also the problem that process that pressure source 100 slowly boosts and reduce pressure to pressure switch 103 is comparatively time-consuming, " embodiment 2 " of scheme one is in order to solve this problem further, it is proposed to a kind of method of detection pressure switch switching value being rapidly completed boosting and/or pressure reduction.

The value of embodiment 2 and the be different in that k of embodiment 1 is k > 0 (referring to embodiment 2: variable Rate pressure control method).The detection method that embodiment 2 provides is solving on the basis of accuracy and repeatability problem, additionally it is possible to realize quickly detection.

In such scheme one, the ormal weight δ in described detected value obtaining step is setting accuracy, and its value is in the scope of 0.2-0.5 times of described pressure switch precision.Preferred θ >=0.3 of speed regulation θ and θ≤0.7.

In the method for above-mentioned detection pressure switch switching value, in described initial value obtaining step, the pressure in described pressure piping is changed with rate of pressure rise faster or rate of pressure reduction, until detecting that the on off operating mode of described pressure switch switches, obtain force value when described pressure switch state switches as upper switching value initial value R_iOr lower switching value initial value F_i, rate of pressure rise when being switched by described pressure switch state or rate of pressure reduction are as rate of pressure rise initial value v_1iOr rate of pressure reduction initial value v_2i。

Scheme two

Identical with embodiment 1 problem to be solved of scheme one, " embodiment 3 " of scheme two is to solve the problem of accuracy and poor repeatability in the existing pressure switch detection system shown in Fig. 4, the method that a kind of accuracy detection pressure switch switching value high, reproducible, easy to use is provided, the method comprises the following steps:

Initial value obtaining step, obtain described pressure switch in boost process state switching time force value as on switching value initial value R₀And the rate of pressure rise of correspondence is as rate of pressure rise initial value v₁₀, or force value when pressure switch state switches in pressure reduction is as lower switching value initial value F₀And the rate of pressure reduction of correspondence is as rate of pressure reduction initial value v₂₀；

Detected value obtaining step, obtain described pressure switch in boost process state switching time force value as on switching value detected value R_iAnd the rate of pressure rise v of correspondence_1i, or force value when state switches in pressure reduction is as lower switching value detected value F_iAnd the rate of pressure reduction v of correspondence_2i, wherein, i=1,2,3...；

Estimated value obtaining step, the upper switching value detected value including upper switching value initial value got nearest twice or more than twice or the lower switching value detected value including lower switching value initial value are fitted estimating, obtain the upper switching value estimated value of described pressure switchOr lower switching value estimated valueWherein, r=1,2,3...；

Judge step, the difference between maxima and minima in the upper switching value estimated value got nearest twice or more than twice or lower switching value estimated value and ormal weight δ compare, when described difference is more than or equal to described ormal weight δ, return described detected value obtaining step；When described difference is less than described ormal weight δ, the described upper switching value estimated value obtain the last time or lower switching value estimated value are as the upper switching value of described pressure switch or lower switching value.

Rate of pressure rise v in the detected value obtaining step of scheme two, during by rate of pressure rise or rate of pressure reduction compared with pressure switch state switching last time_1(i-1)Or rate of pressure reduction v_2(i-1)Reduce, change pressure described pipeline in plus a speed adjustment amount by pressure control valve and pressure generator with the rate of pressure rise after this reduction or rate of pressure reduction；And the upper switching value detected value including upper switching value initial value that obtained close to last time along with the force value in pressure piping of speed adjustment amount or the lower switching value detected value that includes lower switching value initial value and diminish；Concrete,

Boost process speed adjustment amount is the function of pipeline inner pressure value, and described function representation is Δ V_ij=k (R_i-1-p_j), rate of pressure rise is expressed as V_ij=θ v_1(i-1)+ΔV_ij, wherein, Δ V_ijIt is that the jth in the i-th detected value obtaining step detects the speed adjustment amount walked, V_ijIt is the rate of pressure rise in the i-th detected value obtaining step, v_1(i-1)Rate of pressure rise when being obtain upper switching value detected value in (i-1) detected value obtaining step, R_i-1For the upper switching value detected value detected in (i-1) detected value obtaining step, p_jFor the force value in the described jth detected pressure piping of detection step, k is pressure regulation, and θ is speed regulation, and meets k >=0,0 θ θ < 1, i=1,2,3 ..., j=1,2,3 ...；As k=0, rate of pressure rise is expressed as V_i=θ v_1(i-1)(referring to embodiment 3: based on the constant speed pressure control method of fitting of a polynomial).

Pressure reduction speed adjustment amount is the function of pipeline inner pressure value, and described function representation is Δ V_ij=k (p_j-F_i-1), described rate of pressure reduction is expressed as V_ij=θ v_2(i-1)+ Δ V_ij, wherein, Δ V_ijIt is that the jth in the i-th detected value obtaining step detects the speed adjustment amount walked, V_ijIt is the rate of pressure reduction in the i-th detected value obtaining step, v_2(i-1)Rate of pressure reduction when being obtain lower switching value detected value in (i-1) detected value obtaining step, F_i-1For the lower switching value detected value detected in (i-1) detected value obtaining step, p_jFor the force value in the described jth detected pressure piping of detection step, k is pressure regulation, and θ is speed regulation, and meets k >=0,0 < θ < 1, i=1,2,3 ..., j=1,2,3 ...；As k=0, rate of pressure reduction is expressed as V_i=θ v_2(i-1)(referring to embodiment 3: based on the constant speed pressure control method of fitting of a polynomial).

The detection method that embodiment 3 provides can solve accuracy and repeatability problem.

Identical with embodiment 2 problem to be solved of scheme one, " embodiment 4 " of scheme two is in order to solve the time-consuming problem that the pressure switch detection system shown in Fig. 4 exists further, it is proposed to a kind of method of detection pressure switch switching value being rapidly completed boosting and/or pressure reduction.

The value of embodiment 4 and the be different in that k of embodiment 3 is k > 0 (referring to embodiment 4: based on the variable Rate pressure control method of fitting of a polynomial).The detection method that embodiment 4 provides is solving on the basis of accuracy and repeatability problem, additionally it is possible to realize quickly detection.

In scheme two, described estimated value obtaining step, the polynomial fitting method based on least square is adopted to be fitted estimating to the relation of upper switching value detected value and rate of pressure rise or lower switching value detected value with rate of pressure reduction, and using switching value estimated value corresponding when being zero to rate of pressure rise or rate of pressure reduction as upper switching value estimated value or lower switching value estimated value.

In described judgement step, ormal weight δ is setting accuracy, and its value is in the scope of 0.2-0.5 times of described pressure switch precision.

In described initial value obtaining step, the pressure in described pressure piping is changed with rate of pressure rise faster or rate of pressure reduction, until detecting that the on off operating mode of described pressure switch switches, obtain force value when described pressure switch state switches as upper switching value initial value R_iOr lower switching value initial value F_i, rate of pressure rise when being switched by described pressure switch state or rate of pressure reduction are as rate of pressure rise initial value v_1iOr rate of pressure reduction initial value v_2i。

Adopt technique scheme, the solution have the advantages that: the pressure change of pressure piping is real-time transmitted to controller by pressure transducer by the present invention, the data processing unit being installed in controller obtains this change value of pressure, control instruction is generated according to default Pressure Variation, control pressure generator by pressure control valve and change the pressure in pipeline, complete the detection of pressure switch switching value through repeatedly cycle detection mode.Adopting device provided by the invention to complete the detection of pressure switch switching value, utilize intellectuality to realize quickly detection, improve accuracy in detection, testing result is reproducible, reduces cost of labor, simple to operate, reliable operation.

Accompanying drawing explanation

Fig. 1 is the structured flowchart of the device of the detection pressure switch switching value that the embodiment of the present invention provides；

Fig. 2 is the flow chart of the method for the detection pressure switch switching value of the present invention program one；

Fig. 3 is the flow chart of the method for the detection pressure switch switching value of the present invention program two；

Fig. 4 is the schematic diagram of existing pressure switch detection system；

Fig. 5 is the graph of a relation of the pressure switching value of rate of pressure change and detection in embodiment 1 and embodiment 2；

Fig. 6 is the graph of a relation of the pressure switching value of rate of pressure change and detection in embodiment 3；

Fig. 7 is the graph of a relation of the pressure switching value of rate of pressure change and detection in embodiment 4；

Fig. 8 is the graph of a relation of the pressure switching value of rate of pressure change and detection in embodiment 5.

In figure, accompanying drawing labelling is expressed as:

1: pressure generator, 2: pressure control valve, 3: pressure piping, 4: pressure transducer, 5: controller；51: memory element, 52: data processing unit；6: electrical interface, 7: pipe interface；8: pressure switch；

100: pressure source, 101: standard pressure gauge, 102: isobaric pipeline, 103: pressure switch, 104: on off state acquiring unit.

Detailed description of the invention

Below in conjunction with the drawings and specific embodiments, method and device to the detection pressure switch switching value of the present invention are described in detail.

The present invention is applicable to the detection of various pressure switches, embodiment illustrates only for one of which electronic pressure switch, embodiments of the invention are not limited to these certain exemplary embodiments, and refer to all equivalents and the alternative form that are included in the scope of the present invention, based on the embodiment in the present invention, the every other embodiment that those of ordinary skill in the art obtain under the premise not making creative work, broadly falls into the disclosure of invention.

The structured flowchart of the device of the detection pressure switch switching value that Fig. 1 provides for the embodiment of the present invention.As shown in Figure 1, this device includes pressure generator 1, pressure control valve 2, pressure piping 3, pressure transducer 4 and controller 5, wherein, pressure generator 1, pressure transducer 4 connect the path (in Fig. 1, thick line represents) formed physically by pressure piping 3, with outside pressure switch 8 by pipe interface 7 and above-mentioned path physical connection；Pressure control valve 2 is connected with pressure generator 1 and is used for controlling pressure generator 1, is also connected to controller 5 simultaneously and Stress control data is stored in the controller 5, and receives the control instruction of self-controller 5 to be sent to pressure generator 1；Controller 5 electrically connects with pressure transducer 4, switch 8 with external pressure and be connected (including the modes such as electrical connection or dedicated radio link) by electrical interface 6 logic, to receive the signal from pressure transducer 4 and pressure switch 8, and it is analyzed processing to the data received, and the control instruction of generation is sent to pressure generator 1 by pressure control valve 2；Pressure piping 3 is connected with the pipeline input interface end of pressure switch 8 by pipe interface 7, being sent in pressure switch 8 by pressure produced by pressure generator 1, controller 5 is connected the signal being used for receiving pressure switch 8 contact action with the output switch parameter end logic of pressure switch 8 simultaneously.

Wherein, pressure generator 1 can be atmospheric pressure generator, it is also possible to be hydraulic pressure generator, adopts compression pump to drive；Pressure generator 1 receives the control instruction of self-controller 5 by pressure control valve 2, controls compression pump according to different rates supercharging or decompression；The state of pressure generator 1 can also be sent to controller 5 by pressure control valve 2, and is sent to external equipment 9 (such as computer, liquid crystal display or touch screen) and displays.

Pressure control valve 2 as independent element, can be placed between pressure generator 1 and controller 5, plays signal conveying, conversion intermediation, for instance, pressure control valve 2 can be existing integrating control element；Can also be integrated in controller 5 or in pressure generator 1, be used for controlling compression pump according to different rates supercharging or decompression.Pressure control valve 2 can accept to come the control instruction of self-controller 5, it is also possible to the state of pressure generator 1 is sent to controller 5, is sent to external equipment 9 then through by controller 5.

Pressure transducer 4 is installed on pressure piping 3, for detecting pressure in pressure piping 3, and pressure signal converts to the signal of telecommunication sends controller 5 to.

Electrical interface 6 is the integrated component being provided with multiple electric signal interface, it would be preferable to support the access of different electrical signals or output, and described electrical interface includes switch numbers amount interface, USB interface, serial ports, Ethernet interface etc..Electrical interface 6 can be electrically accessed the output switch parameter end of pressure switch 8 for receiving the signal of telecommunication of pressure switch 8 contact action, controller 5 is transported to be sent by this signal of telecommunication, or it is electrically accessed the external equipments 9 such as computer, liquid crystal display or touch screen, make controller 5 and external equipment 9 carry out data interaction by this electrical interface, show for data acquisition, result, download program, parameter setting, remote debugging and system update etc..Therefore the present invention can be configured display screen by electrical interface 6, makes handheld apparatus, facilitates onsite application；As stationary installation, computer system can also be accessed, it is achieved remotely monitor.

Pipe interface 7 can be provided in the fixed interface on pressure piping 3, it is also possible to is interface detachable, interchangeable, it is possible to is replaced according to the shape facility of the pipeline input interface end of pressure switch 8.

Controller 5 can include memory element 51 and data processing unit 52, memory element 51 electrically connects for the reception of data, transmission and storage respectively with pressure control valve 2, pressure transducer 4 and the pressure switch 8 transmitted by electrical interface 6, and has and carry out the interface of data interaction with data processing unit 52；The data that data processing unit 52 receives from memory element 51 are analyzed processing, and by memory element 51, the control instruction of generation is sent to pressure control valve 2.

The data processing unit 52 of controller 5 sends control instruction to pressure generator 1 by memory element 51, control pressure generator 1 and change the pressure in pressure piping 3, and receive the force value of pressure transducer 4 acquisition and the status information of pressure switch 8, in order to complete the process of data in the detection of pressure switch switching value.

The detection of existing pressure switch switching value is mostly based on following mechanism and realizes: in pressure uphill process, the force value that trigger status changes is upper switching value R (actual value), drop under stress in process, the pressure of trigger status change is lower switching value F (actual value), and R > F, then R-F is called return difference.The existence of return difference enhances the stability of pressure switch work, generally returns extent and looks application scenario and require and different.In the process measured, the pressure value that pressure transducer 4 records is upper or lower switching value detected value, is designated as R_iOr F_i, then measurement error ε_iValue obtained after deducting actual value for i & lt switching value detected value, i.e. ε_1i=R_i-R, ε_2i=F_i-F, wherein, i is for measuring sequence number, and R is the actual value of upper switching value, R_iFor the upper switching value that i & lt detects, ε_1iFor the detection error of switching value in i & lt；F is the actual value of lower switching value, F_iFor the lower switching value that i & lt detects, ε_2iFor the detection error of switching value under i & lt.

When pressure in pressure piping 3 reaches switching point, need to obtain startup contact actuating signal through multiple links, these links include the pressure measxurement of pressure switch, comparing element, the driving of switch, switch measurement and catch the response time of switching and the reading duration etc. of pressure transducer, and these factors can cause the detected value of switching value more than or less than switching value actual value.

Therefore, in measurement process, time delay mainly has two parts, one be from force value arrive switching point to the switching value of output contact action time time delay be t₁, two is be t from receiving switching value time delay to the reading receiving pressure transducer₂, then by the joint effect of two above aspect, then ε_1i=ε₁₁+ε₁₂, ε_2i=ε₂₁+ε₂₂, wherein, ε_1iFor the detection error of upper switching value, ε₁₁For t time delay₁The error caused, ε₁₂For t time delay₂The error caused；ε_2iFor the detection error of lower switching value, ε₂₁For t time delay₁The error caused, ε₂₂For t time delay₂The error caused.Usual t₁、t₂Smaller, the therefore mean pressure variations rate in this time periodCan be used as definite value, namelyIn repeated detection process, pressure transducer, pressure switch delay be basically unchanged, therefore go up switching value or lower switching value detection error ε_1i、ε_2iIt is substantially proportional to pressure change rate when triggering pressure switch action.

If pressure amplitude is Δ p, the measurement time is t, and pressure change rate is constant in v, then when measuring time t and enough descend, t=Δ p/v, namely measures time t and pressure change rate v substantially inversely.

Based on this, in order to the switching value of accurate pressure switch be detected, it is desirable to when pressure switch on off operating mode switches, pressure change rate v goes to zero；On the other hand, in order to save the measurement time, it is desirable to adopt bigger pressure change rate v to carry out pressure scanning.Because pressure change rate is excessive, practical operation can cause that pressure switch switching point testing result is inaccurate；The speed of each detection process is inconsistent causes that repeatability is poor.

From analyzing above, when the state of pressure switch 8 switches, rate of pressure change is more little, the accuracy of detection pressure switch switching value is more high, therefore the present invention is used to adopt the method for rate of pressure change Approach by inchmeal zero to carry out the detection of switching value of pressure switch, make detected value approaching to reality value, and the basis for estimation that the ormal weight δ being adopted as setting accuracy terminates circulation as detection can realize above-mentioned purpose.

Below in conjunction with apparatus of the present invention, the detection method of pressure switch switching value is described in detail.The present invention proposes two kinds of embodiments.

Scheme one

Fig. 2 is the pressure switch switching value detection method flow chart of scheme one, and the method can complete with the device of the detection pressure switch switching value shown in Fig. 1.The detection of this pressure switch switching value comprises the following steps:

S100 initial value obtaining step: obtain described pressure switch 8 in boost process state switching time force value as on switching value initial value R₀And the rate of pressure rise of correspondence is as rate of pressure rise initial value v₁₀, or force value when pressure switch 8 state switches in pressure reduction is as lower switching value initial value F₀And the rate of pressure reduction of correspondence is as rate of pressure reduction initial value v₂₀。

In this step, the pressure in described pressure piping 3 is changed with rate of pressure rise faster or rate of pressure reduction, until detecting that the on off operating mode of described pressure switch 8 switches, obtain the force value during switching of described pressure switch 8 state as upper switching value initial value R by pressure transducer 4₀Or lower switching value initial value F₀, rate of pressure rise when described pressure switch 8 state being switched or rate of pressure reduction are as rate of pressure rise initial value v₁₀Or rate of pressure reduction initial value v₂₀。

Herein, in initial value acquisition process, the rate of pressure rise started or rate of pressure reduction are determined by empirical value generally according to the performance of pressure switch 8, generally choose the upper limit near rate of pressure rise empirical value or rate of pressure reduction empirical value to approach the switching value of pressure switch 8 as early as possible, thus reducing the detection time.

Rate of pressure rise or rate of pressure reduction during pressure switch switching can be obtained by program computation, force value in a pressure piping 3 process to the force value read in pressure piping 3 next time is read as a detection step by pressure transducer 4, the force value then detected during pressure switch switching deducts the force value that a detection step is detected, again divided by the detection step time used, it is rate of pressure rise v during pressure switch switching₁₀Or rate of pressure reduction v₂₀；If pressure transducer 4 has speed measuring function, it is also possible to record rate of pressure rise v during pressure switch switching by pressure transducer 4₁₀Or rate of pressure reduction v₂₀；Rate of pressure rise or rate of pressure reduction when pressure switch 8 switches can also set based on experience value.

S200 detected value obtaining step, with meet this pressure switch state switching time rate of pressure rise or rate of pressure reduction compared with last time pressure switch state switching time rate of pressure rise v_1(i-1)Or rate of pressure reduction v_2(i-1)Little mode obtain described pressure switch in boost process state switching time force value as on switching value detected value R_iAnd the rate of pressure rise v of correspondence_1i, or force value when state switches in pressure reduction is as lower switching value detected value F_iAnd the rate of pressure reduction v of correspondence_2i, wherein, i=1,2,3...；

In above-mentioned detected value obtaining step, from starting to detect the process that force value switches to pressure switch 8 state, rate of pressure rise or rate of pressure reduction can be the arbitrary sizes in pressure switch zone of reasonableness, preferably, to change the pressure in pressure piping 3 than rate of pressure rise faster or rate of pressure reduction, this speed can be rate of pressure rise or the rate of pressure reduction of constant, can also be rate of pressure rise or the rate of pressure reduction of change, such as, the rate of pressure rise in detected value obtaining step or rate of pressure reduction are the function of force value in the pressure piping 3 detected；When pressure switch 8 state switches, meet rate of pressure rise or rate of pressure reduction than last time pressure switch 8 state switching time rate of pressure rise v_1(i-1)Or rate of pressure reduction v_2(i-1)Little condition.

S300 judges step, the difference between maxima and minima in the upper switching value detected value including upper switching value initial value got nearest twice or more than twice or the lower switching value detected value including lower switching value initial value and ormal weight δ compare, when described difference is more than or equal to described ormal weight δ, return described detected value obtaining step；When described difference is less than described ormal weight δ, the described upper switching value detected value obtain the last time or lower switching value detected value are as the upper switching value of described pressure switch or lower switching value.

In the judgement step of said method, the difference that can adopt the switching value detected value of nearest twice acquisition compares with described ormal weight δ, carry out whether determination methods terminates, the maximum of switching value detected value obtained and the difference of minima can also be adopted nearest three times or more than three times to compare with described ormal weight δ, judge whether the method terminates, wherein, described ormal weight δ can set according to the required precision of the precision of pressure switch 8 and application scenarios, ormal weight δ can be fixed value, may not be fixed value, such as, the value of ormal weight δ used in the judgement step of twice detection process is different；Adopting the pressure switch switching value credibility that later approach obtains higher, correspondingly, the detection time may increase, and can select according to testing requirement compromise.

Alternatively, the method can also include initialization step before S100 step, and the parameters related in the method is configured, for instance the setting of ormal weight δ, and other need the parameter arranged to determine according to specific embodiment；If parameters value is fixed as default value, it is also possible to ignore this step.

Alternatively, the method can also include output step after S300 judges step, it is about in last circulation the upper switching value detected value that obtains and lower switching value detected value as the upper switching value of pressure switch 8 and lower switching value record in the controller 5, and result is sent to external equipment 9.

The process that realizes of above-mentioned steps can have different deformation according to different embodiments.

The method can be used for individually detecting the upper switching value of pressure switch or lower switching value, it is also possible to detect the upper switching value of pressure switch and lower switching value in simultaneously.

Judge step adopts nearest twice the difference obtaining switching value detected value maximum and minima and described ormal weight δ situation about comparing for the upper switching value detecting pressure switch and lower switching value simultaneously and above-mentioned below, two kind different embodiments (embodiment 1 and embodiment 2) are discussed in detail.

Embodiment 1: constant speed pressure control method

Flow process shown in Figure 2, embodiment 1 adopts procedure below to detect the switching value of pressure switch:

Initial value obtaining step: changed the pressure in pressure piping 3 with rate of pressure rise faster or rate of pressure reduction by pressure generator 1, until detect that the on off operating mode of described pressure switch 8 switches, when obtaining the switching of described pressure switch 8 state by pressure transducer 4, the force value in pressure piping 3 is as upper switching value initial value R₀Or lower switching value initial value F₀, and corresponding rate of pressure rise initial value v₁₀Or rate of pressure reduction initial value v₂₀, and the value obtained is stored in the controller 5.

Detected value obtaining step: by pressure generator 1 from lower switching value F_(i-1)Sentence V_i=θ V_1(i-1)Rate of pressure rise raised pressure pipeline 3 in pressure, the upper switching value that when occurring state to switch pressure switch 8, pressure transducer 4 obtains is as upper switching value detected value R_i, and obtain rate of pressure rise v when pressure switch 8 state switches_1i；By pressure generator 1 from upper switching value R_iSentence V_i=θ V_2(i-1)Rate of pressure reduction reduce the pressure in pressure piping 3, the incision value that when occurring state to switch pressure switch 8, pressure transducer 4 obtains is as lower switching value detected value F_i, and obtain rate of pressure rise v when pressure switch 8 state switches_2i, and the detected value obtained is stored in the controller 5, wherein, i is cycle-index, and θ is speed regulation, and meets i=1,2,3..., 0 < θ < 1.

Judge step: if r >=1 and meet:

max(R_i-1,R_i)-min(R_i-1,R_i) < δ and max (F_i-1,F_i)-min(F_i-1,F_i) θ δ, then detect, using upper switching value as pressure switch 8 of the upper switching value detected value that obtains in circulation for the last time and lower switching value detected value and lower switching value, and be stored in controller 5, exit circulation；Otherwise cycle-index i adds 1, and turns to detected value obtaining step, wherein, it is stipulated that amount δ is setting accuracy, and its span is 0.2-0.5 times of pressure switch 8 precision.

In said process, if needing to reset ormal weight δ and the isoparametric value of speed regulation θ, then this embodiment can also include initialization step；If described equipment connects external equipment 9, then embodiment 1 may also include output step.

Cycle-index in said process depends on set ormal weight δ, speed regulation θ and initial boost speed v₁₀And/or initial decompression speed v₂₀Deng, the detected value obtaining step medium-rate regulation θ of said method is more big, every time in detection rate of pressure rise or rate of pressure reduction reduce more slow, it is necessary to time more short, but the detection number of times that reaching required precision needs generally can increase, and total detection time is more long accordingly；Contrary speed regulation θ is more little, every time in detection rate of pressure rise or rate of pressure reduction reduce more fast, corresponding detection number of times generally can reduce, but every time the detection execution time more long.Additionally, every time in detection rate of pressure rise or rate of pressure reduction compressed switch with last time state switching time rate of pressure rise or rate of pressure reduction compared with variable quantity only small time, upper switching value detected value or the lower switching value detected value variable quantity of the pressure switch obtained are also only small, particularly when rate of pressure rise or rate of pressure reduction itself are bigger, there will be the difference of switching value detected value or lower switching value detected value on twice obtained and meet the Rule of judgment judging in step, but the situation that between the upper switching value of the pressure switch obtained or lower switching value and actual value, difference is very big.Inventor learns by making great efforts research, for constant speed pressure control method, by the scope control of speed regulation θ in 0.3≤θ≤0.7, it is possible to eliminate drawbacks described above.Ormal weight δ is generally set with reference to the nominal value of pressure switch and the required precision of application scenarios, and its span can be 0.2-0.5 times of pressure switch 8 precision；0.2-0.5 times that span is pressure switch 8 precision of so-called ormal weight δ, refer to that the value of ormal weight δ can be certain fixed value in the scope of 0.2-0.5 times of pressure switch 8 precision, may not be fixed value, such as, the value of ormal weight δ used in the judgement step of twice detection process is different.

Embodiment 2: variable Rate pressure control method

In order to reduce the detection time further while meeting as the ormal weight δ of setting accuracy, the embodiment 1 of said method is improved, detection process each time adopts rate of pressure rise and the rate of pressure reduction of real-time change, namely distance pressure switch state switching point farther out time, pressure regulation is relatively big, is beneficial to the saving time；When close to pressure switch state switching point, pressure change rate diminishes, and detection error reduces.In detection process, pressure transducer 4 is read force value in a pressure piping 3 to the process of the force value read in pressure piping 3 next time as a detection step；Using the process of the upper switching value completing one-time detection pressure switch and lower switching value as a circulation.

Each step included by variable Rate pressure control method of embodiment 2 is essentially identical with each step of embodiment 1, it is distinctive in that, in detected value obtaining step, pressure generator 1 changes the rule difference of the pressure in pressure piping 3, and the detected value obtaining step that embodiment 2 adopts is as follows:

Detected value obtaining step: by pressure generator 1 from lower switching value F_i-1Sentence V_ij=θ v_1(i-1)+k(R_i-1-p_j) rate of pressure rise raised pressure pipeline 3 in pressure, the upper switching value that when pressure switch 8 state being switched, pressure transducer 4 obtains is as upper switching value detected value R_i, and obtain rate of pressure rise v when pressure switch 8 state switches_1i；Wherein,_iFor cycle-index, i=1,2,3 ..., j is detection step number, j=1,2,3 ..., k is pressure regulation, and θ is speed regulation, 0 < k, 0 < θ < 1；p_jFor pressure sensor unit 3_jForce value detected in detection step；v_1(i-1)It is rate of pressure rise during acquisition above switching value detected value in (i-1) detected value obtaining step or rate of pressure rise initial value, R_i-1For the upper switching value detected value detected in the i-th-1 detected value obtaining step or on switching value initial value；

By pressure generator 1 from upper switching value detected value R_iSentence V_ij=θ v_2(i-1)+ k (p_j-F_i-1) rate of pressure reduction reduce the pressure in pressure piping 3, the incision value that when pressure switch 8 state being switched, pressure transducer 4 obtains is as lower switching value detected value F_i, and obtain rate of pressure rise v when pressure switch state switches_2i；And the value of above-mentioned acquisition is stored in controller 5；Wherein, p_jFor force value detected in pressure sensor unit 3 jth detection step；v_2(i-1)It is rate of pressure reduction during pressure switch 8 state switching in (i-1) detected value obtaining step or rate of pressure reduction initial value, F_i-1For the lower switching value detected value detected in the i-th-1 detected value obtaining step or lower switching value initial value.

Equally, this embodiment can also include initialization step and/or output step.

Adopting the rate of pressure rise of real-time change or rate of pressure reduction to change the pressure in pressure piping 3, the upper or lower switching value detected value of detection pressure switch, pressure regulation k is numerically the fixed value more than zero.Equally, speed regulation θ scope is also required to eliminate the defect mentioned in real-time mode 1, and for variable Rate pressure control method, the scope control of speed regulation θ is in 0.3≤θ≤0.7.Ormal weight δ is generally set with reference to the nominal value of pressure switch and the required precision of application scenarios, and its span can be 0.2-0.5 times of pressure switch 8 precision；0.2-0.5 times that span is pressure switch 8 precision of so-called ormal weight δ, refer to that the value of ormal weight δ can be certain fixed value in the scope of 0.2-0.5 times of pressure switch 8 precision, may not be fixed value, such as, the value of ormal weight δ used in the judgement step of twice detection process is different.

The method can reduce the detection time further, makes switching value detected value or lower switching value detected value quickly approaching to reality value, and repeatability is better.

Scheme two

Fig. 3 is the pressure switch switching value detection method flow chart of scheme two, and the method can complete with the device of the detection pressure switch switching value shown in Fig. 1.The detection of this pressure switch switching value comprises the following steps:

S10 initial value obtaining step: obtain described pressure switch 8 in boost process state switching time force value as on switching value initial value R₀And the rate of pressure rise of correspondence is as rate of pressure rise initial value v₁₀, or force value when pressure switch 8 state switches in pressure reduction is as lower switching value initial value F₀And the rate of pressure reduction of correspondence is as rate of pressure reduction initial value v₂₀。

In this step, the pressure in described pressure piping 3 is changed with rate of pressure rise faster or rate of pressure reduction, until detecting that the on off operating mode of described pressure switch 8 switches, obtain the force value during switching of described pressure switch 8 state as upper switching value initial value R by pressure transducer 4₀Or lower switching value initial value F₀, rate of pressure rise when described pressure switch 8 state being switched or rate of pressure reduction are as rate of pressure rise initial value v₁₀Or rate of pressure reduction initial value v₂₀。

Herein, in initial value acquisition process, the rate of pressure rise started or rate of pressure reduction are determined by empirical value generally according to the performance of pressure switch 8, generally choose the upper limit near rate of pressure rise empirical value or rate of pressure reduction empirical value to approach the switching value of pressure switch 8 as early as possible, thus reducing the detection time.

Rate of pressure rise or rate of pressure reduction during pressure switch switching can be obtained by program computation, force value in a pressure piping 3 process to the force value read in pressure piping 3 next time is read as a detection step by pressure transducer 4, the force value then detected during pressure switch switching deducts the force value that a detection step is detected, again divided by the detection step time used, it is rate of pressure rise v during pressure switch switching₁₀Or rate of pressure reduction v₂₀；If pressure transducer 4 has speed measuring function, it is also possible to record rate of pressure rise v during pressure switch switching by pressure transducer 4₁₀Or rate of pressure reduction v₂₀；Rate of pressure rise or rate of pressure reduction when pressure switch 8 switches can also set based on experience value.

S20 detected value obtaining step, obtain pressure switch 8 in boost process state switching time force value as on switching value detected value R_iAnd the rate of pressure rise v of correspondence_1i, or force value when state switches in pressure reduction is as lower switching value detected value F_iAnd the rate of pressure reduction v of correspondence_2i, wherein, i=1,2,3....

In above-mentioned detected value obtaining step, from starting to detect the process that pressure switch 8 state switches, rate of pressure rise or rate of pressure reduction can be the speed of the arbitrary size in zone of reasonableness, preferably, to change the pressure in pressure piping 3 than rate of pressure rise faster or rate of pressure reduction, this speed can be rate of pressure rise or the rate of pressure reduction of constant, can also be rate of pressure rise or the rate of pressure reduction of change, such as, the rate of pressure rise in detected value obtaining step or rate of pressure reduction are the function of force value in the pressure piping 3 detected.

S30 estimated value obtaining step, the upper switching value detected value including upper switching value initial value got nearest twice or more than twice or the lower switching value detected value including lower switching value initial value are fitted estimating, obtain the upper switching value of described pressure switchEstimated value or lower switching value estimated valueWherein, r=1,2,3....

Above-mentioned estimated value obtaining step S30 can adopt the polynomial fitting method based on least square be fitted estimating, due to for low order equation, method of least square utilize optimal square approach can on an interval the more uniform approximating function of ratio, and simple, effective greatly.

S40 judges step, the difference between maxima and minima in the upper switching value estimated value got nearest twice or more than twice or lower switching value estimated value and ormal weight δ compare, when described difference is more than or equal to described ormal weight δ, return described detected value obtaining step S20；When described difference is less than described ormal weight δ, the described upper switching value estimated value obtain the last time or lower switching value estimated value are as the upper switching value of described pressure switch or lower switching value.

In the judgement step S40 of said method, the difference that can adopt the switching value estimated value of nearest twice acquisition compares with described ormal weight δ, carry out whether determination methods terminates, the maximum of switching value estimated value obtained and the difference of minima can also be adopted nearest three times or more than three times to compare with described ormal weight δ, judge whether the method terminates, wherein, described ormal weight δ can set according to the required precision of the precision of pressure switch 8 and application scenarios, ormal weight δ can be fixed value, may not be fixed value, such as, the value of ormal weight δ used in the judgement step of twice detection process is different；Adopting the pressure switch switching value credibility that later approach obtains higher, correspondingly, the detection time may increase, and can select according to testing requirement compromise.

Alternatively, the method can also include initialization step before S10 step, and the parameters related in the method is configured, for instance the setting of ormal weight δ, and other need the parameter arranged to determine according to specific embodiment；If parameters value is fixed as default value, it is also possible to ignore this step.

Alternatively, the method can also include output step after S40 judges step, it is about in last circulation the upper switching value estimated value that obtains and lower switching value estimated value as the upper switching value of pressure switch 8 and lower switching value record in the controller 5, and sends result to external equipment.

The process that realizes of above-mentioned steps can have different deformation according to different embodiments.

The method can be used for individually detecting the upper switching value of pressure switch or lower switching value, it is also possible to detect the upper switching value of pressure switch 8 and lower switching value in simultaneously.

Below for the upper switching value detecting pressure switch and lower switching value simultaneously and in the difference of the above-mentioned switching value estimated value maximum judging to adopt nearest twice acquisition in step and minima and described ormal weight δ situation about comparing, three kind different embodiments (embodiment 3-5) are discussed in detail.

Embodiment 3: based on the constant speed pressure control method of fitting of a polynomial

It is operated with the device of the detection pressure switch switching value shown in Fig. 1, in detection process, changes the pressure in pressure piping 3 with the rate of pressure rise of constant and rate of pressure reduction, including following step:

Initial value obtaining step: changed the pressure in pressure piping 3 with rate of pressure rise faster or rate of pressure reduction by pressure generator 1, until detect that the on off operating mode of described pressure switch 8 switches, when obtaining the switching of described pressure switch 8 state by pressure transducer 4, the force value in pressure piping 3 is as upper switching value initial value R₀Or lower switching value initial value F₀, and corresponding rate of pressure rise initial value v₁₀Or rate of pressure reduction initial value v₂₀, and the value obtained is stored in the controller 5.

Detected value obtaining step: by pressure generator 1 from lower switching value F_(i-1)Sentence V_i=θ V_1(i-1)Rate of pressure rise raised pressure pipeline 3 in pressure, the upper switching value that when occurring state to switch pressure switch 8, pressure transducer 4 obtains is as upper switching value detected value R_i, and obtain rate of pressure rise v when pressure switch 8 state switches_1i；By pressure generator 1 from upper switching value R_iSentence V_i=θ V_2(i-1)Rate of pressure reduction reduce the pressure in pressure piping 3, the incision value that when occurring state to switch pressure switch 8, pressure transducer 4 obtains is as lower switching value detected value F_i, and obtain rate of pressure rise v when pressure switch 8 state switches_2i, and the detected value obtained is stored in the controller 5, wherein,_iFor cycle-index, θ is speed regulation, and meets i=1,2,3..., 0 < θ < 1.

Estimated value obtaining step: if i >=1, what get nearest twice includes upper switching value initial value R₀At interior upper switching value detected value R_iIt is fitted estimating, obtains the upper switching value estimated value of described pressure switchAnd switching value initial value F under the including that nearest twice is got₀At interior lower switching value detected value F_iIt is fitted estimating, obtains the lower switching value estimated value of described pressure switchOtherwise cycle-index i adds 1, and turns to detected value obtaining step, and wherein, r is estimation number of times, and r=1,2,3....

Judge step: if r >=2 and meet:

Then detect, using upper switching value as pressure switch 8 of the upper switching value estimated value that obtains in circulation for the last time and lower switching value estimated value and lower switching value, and be stored in controller 5, exit circulation；Otherwise cycle-index i adds 1, and estimated value number r adds 1, and turns to detected value obtaining step, wherein, it is stipulated that 0.2-0.5 times that span is pressure switch 8 precision of amount δ.

In said method, if needing to reset ormal weight δ and the isoparametric value of speed regulation θ, then this embodiment can also include initialization step；If described equipment connects external equipment, then embodiment 3 may also include output step.

The cycle-index of said method depends on set ormal weight δ, speed regulation θ and initial boost speed v₁₀And/or initial decompression speed v₂₀Deng, the detected value obtaining step medium-rate regulation θ of said method is more big, every time in detection rate of pressure rise or rate of pressure reduction reduce more slow, it is necessary to time more short, but the detection number of times that reaching required precision needs generally can increase, and total detection time is more long accordingly；Contrary speed regulation θ is more little, every time in detection rate of pressure rise or rate of pressure reduction reduce more fast, corresponding detection number of times generally can reduce, but every time the detection execution time more long, middle need compromise to consider actually detected.Ormal weight δ is generally set with reference to the nominal value of pressure switch and the required precision of application scenarios, and its span can be 0.2-0.5 times of pressure switch 8 precision；0.2-0.5 times that span is pressure switch 8 precision of so-called ormal weight δ, refer to that the value of ormal weight δ can be certain fixed value in the scope of 0.2-0.5 times of pressure switch 8 precision, may not be fixed value, such as, the value of ormal weight δ used in the judgement step of twice detection process is different.

Embodiment 4: based on the variable Rate pressure control method of fitting of a polynomial

In order to reduce the detection time while meeting repeatability index δ further, the embodiment 3 of said method is improved, detection process each time adopts rate of pressure rise and the rate of pressure reduction of real-time change, namely distance pressure switch state switching point farther out time, pressure regulation is relatively big, is beneficial to the saving time；When close to pressure switch state switching point, pressure change rate diminishes, and detection error reduces.In detection process, pressure transducer 4 is read force value in a pressure piping 3 to the process of the force value read in pressure piping 3 next time as a detection step；Using the process of the upper switching value completing one-time detection pressure switch and lower switching value as a circulation.

Each step included by variable Rate pressure control method of embodiment 4 is essentially identical with each step of embodiment 3, it is distinctive in that, in detected value obtaining step, pressure generator 1 changes the rule difference of the pressure in pressure piping 3, and the detected value obtaining step that embodiment 4 adopts is as follows:

Detected value obtaining step: by pressure generator 1 from lower switching value F_i-1Sentence V_ij=θ v_1(i-1)+k(R_i-1-p_j) rate of pressure rise raised pressure pipeline 3 in pressure, the upper switching value that when pressure switch 8 state being switched, pressure transducer 4 obtains is as upper switching value detected value R_i, and obtain rate of pressure rise v when pressure switch 8 state switches_1i；Wherein, i is cycle-index, i=1,2,3 ..., j is detection step number, j=1,2,3 ..., k is pressure regulation, and θ is speed regulation, 0 < k, 0 < θ < 1；p_jFor force value detected in pressure sensor unit 3 jth detection step；v_1(i-1)It is rate of pressure rise during acquisition above switching value detected value in (i-1) detected value obtaining step or rate of pressure rise initial value, R_i-1For the upper switching value detected value detected in the i-th-1 detected value obtaining step or on switching value initial value；

By pressure generator 1 from upper switching value detected value R_iSentence V_ij=θ v_2(i-1)+k(p_j-F_i-1) rate of pressure reduction reduce the pressure in pressure piping 3, the incision value that when pressure switch 8 state being switched, pressure transducer 4 obtains is as lower switching value detected value F_i, and obtain rate of pressure rise v when pressure switch state switches_2i；And the value of above-mentioned acquisition is stored in controller 5；Wherein, p_jFor force value detected in pressure sensor unit 3 jth detection step；v_2(i-1)It is rate of pressure reduction during pressure switch 8 state switching in (i-1) detected value obtaining step or rate of pressure reduction initial value, F_i-1For the lower switching value detected value detected in the i-th-1 detected value obtaining step or lower switching value initial value.

Equally, this embodiment can also include initialization step and/or output step.

Adopting the rate of pressure rise of real-time change or rate of pressure reduction to change the pressure in pressure piping 3, the upper or lower switching value detected value of detection pressure switch, pressure regulation k is numerically the fixed value more than zero.Equally, it is stipulated that amount δ is generally set with reference to the nominal value of pressure switch and the required precision of application scenarios, and its span can be 0.2-0.5 times of pressure switch 8 precision；0.2-0.5 times that span is pressure switch 8 precision of so-called ormal weight δ, refer to that the value of ormal weight δ can be certain fixed value in the scope of 0.2-0.5 times of pressure switch 8 precision, may not be fixed value, such as, the value of ormal weight δ used in the judgement step of twice detection process is different.

The method can reduce the detection time further, makes switching value detected value or lower switching value detected value quickly approaching to reality value, and repeatability is better.

Embodiment 5: Fuzzy Control platen press

In this embodiment, force value that controller 5 obtains according to pressure transducer 4 and the status information of pressure switch 8, the pressure lifting of pressure piping is provided and indicative guides rule；Operator can operate pressure generator 1 according to the instruction of controller 5 and realize boosting and pressure reduction.Boosting according to pressure switch 8 or blood pressure lowering upper rate limit, upper rate limit is divided into different rates scope, such as, guide rule can be that simple " slowly boosting ", " middling speed boosting ", " soon boosting ", " slow blood pressure lowering ", " middling speed blood pressure lowering ", " fast blood pressure lowering " etc. are fuzzy and guide rule.

Specifically, the device of the detection pressure switch switching value shown in the method application drawing 1 is operated, and in detection process, operator changes the pressure in pressure piping 3 according to the instruction operation pressure generator 1 of controller 5, including following step:

Initial value obtaining step: operation pressure generator 1 changes the pressure in pressure piping 3 with rate of pressure rise faster or rate of pressure reduction, until detect that the state of described pressure switch 8 switches, when obtaining the switching of described pressure switch 8 state by pressure transducer 4, the force value in pressure piping 3 is as upper switching value initial value R₀Or lower switching value initial value F₀, and corresponding rate of pressure rise initial value v₁₀Or rate of pressure reduction initial value v₂₀, and the value obtained is stored in the controller 5.

Detected value obtaining step: operation pressure generator 1 is from lower switching value F_(i-1)Place is according to the fuzzy pressure guided in rule raised pressure pipeline 3 of controller 5, and the upper switching value that when occurring state to switch pressure switch 8, pressure transducer 4 obtains is as upper switching value detected value R_i, and obtain rate of pressure rise v when pressure switch 8 state switches_1i；By pressure generator 1 from upper switching value R_iPlace guides rule to reduce the pressure in pressure piping 3 according to the fuzzy of controller 5, and the incision value that when occurring state to switch pressure switch 8, pressure transducer 4 obtains is as lower switching value detected value F_i, and obtain rate of pressure rise v when pressure switch 8 state switches_2i, and the detected value obtained is stored in the controller 5, wherein, i is cycle-index, and θ is speed regulation, and meets i=1,2,3....

Estimated value obtaining step: if i >=1, what get nearest twice includes upper switching value initial value R₀At interior upper switching value detected value R_iIt is fitted estimating, obtains the upper switching value of described pressure switchAnd switching value initial value F under the including that nearest twice is got₀At interior lower switching value detected value F_iIt is fitted estimating, obtains the lower switching value estimated value of described pressure switchOtherwise cycle-index i adds 1, and turns to detected value obtaining step, and wherein, r is estimation number of times, and r=1,2,3....

Judge step: if r >=2 and meet:

Then detect, using upper switching value as pressure switch 8 of the upper switching value estimated value that obtains in circulation for the last time and lower switching value estimated value and lower switching value, and be stored in controller 5, exit circulation；Otherwise cycle-index i adds 1, and estimated value number r adds 1, and turns to detected value obtaining step, wherein, it is stipulated that 0.2-0.5 times that span is pressure switch 8 precision of amount δ.

In said method, if needing to reset ormal weight δ and the isoparametric value of speed regulation θ, then this embodiment can also include initialization step；If described equipment connects external equipment 9, then this embodiment may also include output step.

Embodiment 3 and embodiment 4 all require that the pressure of the buck rate on pressure pipeline that pressure generator 1 provides according to controller 5 controls in real time, implement it is generally required to be equipped with automatic measurement and control device, have advantage accurately, fast and easily.Embodiment 5 is the simple realization of apparatus of the present invention, is capable of the inventive method equally and pressure switch switching value is measured accurately, and can use existing major part pressure-generating device, has advantage simple, practical, that cost is low.

Embodiment

The embodiment detecting pressure switch switching value below for the invention described above carries out experimental verification, and wherein tested pressure switch is the CATO pressure switch of PN30-P060G14H3AQ, and concrete parameter index is as shown in table 1.

The parameter list of the tested pressure switch of table 1

Measurand	CATO electron pressure switch
		Model	PN30-P060G14H3AQ
Range (kPa)	6000
		Precision	0.5%f.s (0.5% range)

In this experiment, with above-mentioned CATO pressure switch for detection object, in initial value obtaining step, boost or rate of pressure reduction blood pressure lowering with the rate of pressure rise of fixing initial rate about 300kPa/s, it is thus achieved that upper switching value initial value；The span of speed regulation θ is 0.4～0.6, and pressure regulation k is about 0.5, it is stipulated that amount δ is set to 6kPa (0.1% range).

The testing result of embodiment 1 and embodiment 2 is listed in table 2 and table 3, and the relation between the pressure switching value of its rate of pressure change and detection figure 5 illustrates.As shown in table 2 and table 3, embodiment 1 adopts constant speed pressure control method to carry out constant speed in each cyclic process and raises or reduce the pressure in pressure piping 3, circulates and can detect switching value 4066kPa 5 times, 68.3 seconds consuming time,, circulate and can detect lower switching value 3858kPa for 6 times, 162.3 seconds consuming time；Embodiment 2 adopts variable Rate pressure control method to need circulation to obtain upper switching value 4066kPa for 6 times, 33.7 seconds consuming time, circulates the lower switching value 3852kPa of 6 detections, 53.5 seconds consuming time；And when detecting loop termination, the percentage speed variation during switching of pressure switch 8 state is all reduced to less speed, and the difference of the testing result of two kinds of embodiments is less than ormal weight δ (6kPa), and difference is little, it is ensured that the accuracy of testing result；The obvious starting stage adopts within pressure scanning scope is rapidly contracted to about 3620～4300kPa by 0～6000kPa by pressure change rate (300kPa/s) faster, shortens the time of detection；Measurement process when embodiment 2 adopts variable Rate mode to be accelerated away from switching value, is greatly shortened the required detection time further.

The testing result of the upper switching value of table 2 embodiment 1 and embodiment 2

The testing result of the lower switching value of table 3 embodiment 1 and embodiment 2

The testing result of embodiment 3 is listed in table 4 and table 5, and the relation between the pressure switching value of its rate of pressure change and detection figure 6 illustrates；The testing result of embodiment 4 is listed in table 6 and table 7, and the relation between the pressure switching value of its rate of pressure change and detection figure 7 illustrates；The testing result of embodiment 5 is listed in table 8 and table 9, and the relation between the pressure switching value of its rate of pressure change and detection figure 8 illustrates.

As shown in table 4-table 7, embodiment 3 adopts constant speed pressure control method to raise or reduce the pressure in pressure piping 3 in each cyclic process, circulates and can detect switching value 4049kPa for 4 times, 39.2 seconds consuming time, circulate and can detect lower switching value 3863kPa for 5 times, 89.9 seconds consuming time；Embodiment 4 adopts variable Rate pressure control method raise or reduce the pressure in pressure piping 3, it is necessary to circulates and obtains upper switching value 4051kPa for 5 times, 33.7 seconds consuming time, circulates the lower switching value 3858kPa of 4 detections, 29.3 seconds consuming time；During two kinds of embodiment detection loop terminations, the percentage speed variation during switching of pressure switch 8 state is all reduced to less speed, the difference of the testing result of two kinds of embodiments is less than ormal weight δ (i.e. 6kPa), difference is little, it is ensured that the accuracy of testing result；The obvious starting stage adopts within pressure scanning scope is rapidly contracted to about 3620～4300kPa by 0～6000kPa by pressure change rate (300kPa/s) faster, shortens the time of detection；Measurement process when embodiment 4 adopts variable Rate mode to be accelerated away from switching value, is greatly shortened the required detection time further.

The mode of traditional switching value manually detecting pressure switch 8, pressure change rate when pressure switch switching value not detected makes specific requirement, by artificial experience it is difficult to ensure that the concordance of testing result and accuracy (the switching value detected value referring in embodiment 5).

Embodiment 5 adopts fuzzy pressure control method raise or reduce the pressure in pressure piping 3, it is not required that is gradually reduced rate of pressure rise or rate of pressure reduction, operator is required low, it is achieved be simple.As shown in table 8 and table 9, only need to circulate 3 times and just can detect switching value 4050kPa, circulate and can detect lower switching value 3859kPa 4 times, with the difference of embodiment 3 and the result of embodiment 4 less than ormal weight δ, it is ensured that the accuracy of testing result.Table 4 embodiment

The testing result of the upper switching value of 3

The testing result of the lower switching value of table 5 embodiment 3

The testing result of the upper switching value of table 6 embodiment 4

The testing result of the lower switching value of table 7 embodiment 4

The testing result of the upper switching value of table 8 embodiment 5

The testing result of the lower switching value of table 9 embodiment 5

It will be appreciated by those skilled in the art that these embodiments or embodiment are merely to illustrate the present invention and do not limit the scope of the invention, the various equivalent variations that the present invention is made and amendment belong to the disclosure of invention.

Claims (15)

1. null1. the method detecting pressure switch switching value with detecting device，Wherein，Described detecting device includes the pressure generator connected by pressure piping with pressure switch、Pressure control valve、Pressure transducer and the controller being provided with data processing unit，Pressure transducer is installed on pressure piping and is electrically connected with the controller，Pressure control valve electrically connects with pressure generator and is used for controlling pressure generator，Pressure control valve is electrically connected with the controller，The data processing unit of described controller is analyzed processing and producing corresponding control instruction to obtain data with described pressure transducer and pressure switch electrical connection，Pressure generator is sent to via pressure control valve，The pressure size in described pressure piping is adjusted with this，And make the on off operating mode of described pressure switch switch，Adopt the method for described detection pressure switch switching value to detect the switching value of described pressure switch；

   The method of detection pressure switch switching value, comprises the following steps:

   Initial value obtaining step, the data processing unit of described controller by pressure transducer obtain described pressure switch in boost process state switching time force value as on switching value initial value R₀And the rate of pressure rise of correspondence is as rate of pressure rise initial value v₁₀, or force value when pressure switch state switches in pressure reduction is as lower switching value initial value F₀And the rate of pressure reduction of correspondence is as rate of pressure reduction initial value v₂₀；

   Detected value obtaining step, data processing unit transmits the instruction adjusting pressure size in pressure piping (boosting or blood pressure lowering) by described pressure control valve to pressure generator, by pressure transducer obtain described pressure switch in boost process force value during state switching as on switching value detected value R_iAnd the rate of pressure rise v of correspondence_1i, or force value when state switches in pressure reduction is as lower switching value detected value F_iAnd the rate of pressure reduction v of correspondence_2i, wherein, i=1,2,3...；

   Judge step, difference between the upper switching value detected value of what nearest twice or more than twice was got by data processing unit include upper switching value initial value or the maxima and minima in including the lower switching value detected value of lower switching value initial value compares with ormal weight δ, when described difference is more than or equal to described ormal weight δ, return described detected value obtaining step；When described difference is less than described ormal weight δ, described upper switching value detected value or lower switching value detected value that the last time is obtained by data processing unit export as upper switching value or the lower switching value of described pressure switch.
2. 2. the method for detection pressure switch switching value according to claim 1, it is characterized in that, described controller also includes memory element, memory element electrically connects with pressure control valve, pressure transducer and carries out data interaction, and have and carry out the interface of data interaction with data processing unit, data processing unit and memory element carry out data interaction.
3. 3. the method for detection pressure switch switching value according to claim 1 and 2, it is characterized in that, described detecting device also includes the electrical interface electrically connected with described controller, and described pressure switch transmits pressure switch by this electrical interface to controller and switches the signal of action.
4. 4. the method for detection pressure switch switching value according to claim 3, it is characterized in that, described detecting device also includes external equipment, described external equipment is connected to described controller by described electrical interface, described electrical interface is the integrated component being provided with multiple interfaces, including switch numbers amount interface, USB interface, serial ports, wave point and Ethernet interface, described external equipment can be one or more in computer, LCDs and touch screen.
5. 5. the method for the detection pressure switch switching value according to any one of Claims 1-4, it is characterized in that, in detected value obtaining step, data processing unit by described pressure transducer with meet this pressure switch state switching time rate of pressure rise or rate of pressure reduction compared with last time pressure switch state switching time rate of pressure rise v_1(i-1)Or rate of pressure reduction v_2(i-1)Little mode obtains switching value detected value R_iAnd rate of pressure rise v during pressure switch state switching_1i, or lower switching value detected value F_iAnd rate of pressure reduction v during pressure switch state switching_2i。
6. 6. the method for the detection pressure switch switching value according to any one of Claims 1-4, it is characterized in that, estimated value obtaining step is also had after detected value obtaining step, estimated value obtaining step is the upper switching value detected value including upper switching value initial value that gets nearest twice or more than twice of data processing unit or the lower switching value detected value that includes lower switching value initial value is fitted estimating, obtains the upper switching value estimated value of described pressure switchOr lower switching value estimated valueWherein, r=1,2,3....
7. 7. the method for detection pressure switch switching value according to claim 6, it is characterized in that, in described estimated value obtaining step, the polynomial fitting method based on least square is adopted to be fitted estimating to the relation of upper switching value detected value and rate of pressure rise or lower switching value detected value with rate of pressure reduction, and using switching value estimated value corresponding when being zero to rate of pressure rise or rate of pressure reduction as upper switching value estimated value or lower switching value estimated value.
8. 8. the method for the detection pressure switch switching value according to claim 6 or 7, it is characterized in that, the difference that described judgement step is between the maxima and minima in the upper switching value estimated value or lower switching value estimated value got nearest twice or more than twice compares with ormal weight δ, when described difference is more than or equal to described ormal weight δ, return described detected value obtaining step；When described difference is less than described ormal weight δ, the described upper switching value estimated value obtain the last time or lower switching value estimated value are as the upper switching value of described pressure switch or lower switching value.
9. 9. the method for the detection pressure switch switching value according to any one of claim 1 to 8, it is characterised in that in described judgement step, described ormal weight δ is setting accuracy, its value is in the scope of 0.2-0.5 times of described pressure switch precision.
10. 10. the method for the detection pressure switch switching value according to any one of claim 1 to 9, it is characterised in that in described detected value obtaining step, rate of pressure rise v during by rate of pressure rise or rate of pressure reduction compared with pressure switch state switching last time_1(i-1)Or rate of pressure reduction v_2(i-1)Reduce, change pressure described pipeline in plus a speed adjustment amount by pressure generator with the rate of pressure rise after this reduction or rate of pressure reduction；And the upper switching value detected value including upper switching value initial value that obtained close to last time along with the force value in pressure piping of speed adjustment amount or the lower switching value detected value that includes lower switching value initial value and diminish；Concrete,

    The function that speed adjustment amount is pipeline inner pressure value in boost process, described function representation is Δ V_ij=k (R_i-1-p_j), rate of pressure rise is expressed as V_ij=θ v_1(i-1)+ΔV_ij, wherein, Δ V_ijIt is that the jth in the i-th detected value obtaining step detects the speed adjustment amount walked, V_ijIt is the rate of pressure rise in the i-th detected value obtaining step, v_1(i-1)Rate of pressure rise when being obtain upper switching value detected value in (i-1) detected value obtaining step, R_i-1For the upper switching value detected value detected in (i-1) detected value obtaining step, p_jFor the force value in the described jth detected pressure piping of detection step, k is pressure regulation, and θ is speed regulation, and meets k >=0,0 < θ < 1, i=1,2,3 ..., j=1,2,3 ...；

    Pressure reduction speed adjustment amount is the function of pipeline inner pressure value, and described function representation is Δ V_ij=k (p_j-F_i-1), described rate of pressure reduction is expressed as V_ij=θ v_2(i-1)+ΔV_ij, wherein, Δ V_ijIt is that the jth in the i-th detected value obtaining step detects the speed adjustment amount walked, V_ijIt is the rate of pressure reduction in the i-th detected value obtaining step, v_2(i-1)Rate of pressure reduction when being obtain lower switching value detected value in (i-1) detected value obtaining step, F_i-1For the lower switching value detected value detected in (i-1) detected value obtaining step, p_jFor the force value in the described jth detected pressure piping of detection step, k is pressure regulation, and θ is speed regulation, and meets k >=0,0 < θ < 1, i=1,2,3 ..., j=1,2,3 ...；Preferred θ >=0.3 of speed regulation θ and θ≤0.7.
11. 11. the method for the detection pressure switch switching value according to any one of claim 1 to 10, it is characterized in that, in described initial value obtaining step, the pressure in described pressure piping is changed with rate of pressure rise faster or rate of pressure reduction, until detecting that the on off operating mode of described pressure switch switches, obtain force value when described pressure switch state switches as upper switching value initial value R_iOr lower switching value initial value F_i, rate of pressure rise when being switched by described pressure switch state or rate of pressure reduction are as rate of pressure rise initial value v_1iOr rate of pressure reduction initial value v_2i。
12. 12. the device detecting pressure switch switching value, including the pressure generator connected with pressure switch by pressure piping, it is characterized in that, also include pressure control valve, pressure transducer and the controller being provided with data processing unit, pressure transducer is installed on pressure piping and is electrically connected with the controller, pressure control valve electrically connects with pressure generator and is used for controlling pressure generator, pressure control valve is electrically connected with the controller, the data processing unit of described controller is analyzed processing and producing corresponding control instruction to obtain data with described pressure transducer and pressure switch electrical connection, pressure generator is sent to via pressure control valve.
13. 13. the device of detection pressure switch switching value according to claim 12, it is characterized in that, described controller also includes memory element, and memory element electrically connects and carry out data interaction with pressure control valve, pressure transducer, and has and carry out the interface of data interaction with data processing unit.
14. 14. the device of the detection pressure switch switching value according to claim 12 or 13, it is characterized in that, also include the electrical interface electrically connected with described controller, described electrical interface is the integrated component being provided with multiple interfaces, including switch numbers amount interface, USB interface, serial ports, wave point and Ethernet interface.
15. 15. the device of the detection pressure switch switching value according to claim 12 or 13 or 14, it is characterised in that also including the external equipment being connected to described controller, described external equipment includes computer, LCDs or touch screen.