CN114459340B - Contact area measuring instrument for braking friction plate for mining equipment and manufacturing and measuring method - Google Patents

Contact area measuring instrument for braking friction plate for mining equipment and manufacturing and measuring method Download PDF

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Publication number
CN114459340B
CN114459340B CN202210099652.XA CN202210099652A CN114459340B CN 114459340 B CN114459340 B CN 114459340B CN 202210099652 A CN202210099652 A CN 202210099652A CN 114459340 B CN114459340 B CN 114459340B
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measuring
carbon film
column
film resistor
resistor strip
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CN114459340A (en
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俞越
张峰
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China Inspection Group Gongxin Security Technology Co ltd
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China Inspection Group Gongxin Security Technology Co ltd
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/32Measuring arrangements characterised by the use of electric or magnetic techniques for measuring areas
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/08Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using ultrasonic vibrations
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01DMEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D21/00Measuring or testing not otherwise provided for
    • G01D21/02Measuring two or more variables by means not covered by a single other subclass

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Length Measuring Devices With Unspecified Measuring Means (AREA)
  • Force Measurement Appropriate To Specific Purposes (AREA)

Abstract

The invention relates to a brake friction plate contact area measuring instrument for mining equipment and a manufacturing and measuring method thereof, and belongs to the field of detection. The technical scheme adopted by the invention is as follows: the measuring sheet comprises a measuring sheet, wherein the outermost layers at two sides are poly (p-phenylene terephthamide) fibers, the inner surfaces of the poly (p-phenylene terephthamide) fibers are covered with polyamide imide films, and the edges of the poly (p-phenylene terephthamide) fibers and the polyamide imide films at two sides are connected with a polyamide imide frame in a sealing way; the measuring column is of a hollow structure and is provided with a sealing piston, one end of the hollow structure is communicated with the liquid guide hole on the polyamideimide frame in the measuring sheet, and a carbon film resistor strip is laid on the inner wall of the hollow structure. The measuring host comprises a high-precision AD conversion module, a singlechip and a display screen, wherein the high-precision AD conversion module, the singlechip and the display screen are connected with the carbon film resistor strip. Compared with the traditional measuring technology, the invention has high precision, is convenient to use in full-automatic measurement, can stably enter a file for a long time for storage after the disposable measuring sheet is used, and provides evidence and identification basis for backtracking and responsibility division of accident files.

Description

Contact area measuring instrument for braking friction plate for mining equipment and manufacturing and measuring method
Technical Field
The invention relates to a brake friction plate contact area measuring instrument for mining equipment and a manufacturing and measuring method thereof, belonging to the field of detection.
Background
At present, most of explosion-proof brakes with requirements of mine fixing equipment are braked by adopting plate-type friction plates, most of domestic mine environments are severe, the situation that edges of the friction plates are broken when the friction plates are impacted is very common, and in order to ensure a braking effect, the contact area of the friction plates needs to be detected regularly.
Because the mine fixing equipment has special braking condition and less applicable detection mode, the current detection and inspection mechanism industry mostly adopts a copy paper mode, and the manual measurement is carried out after the friction plate is started to extrude, so that the measurement error is extremely large. In recent years, the copy paper with grid shape is gradually used, time and labor are wasted when a plurality of grids are needed manually, the accurate judgment of the edges of the friction plates is difficult, the copy paper is archived and fades along with the time, the archived data cannot be traced, and the defects are also caused by the fact that some conventional electronic measurement products used by institutions are partially used.
Disclosure of Invention
The invention provides a brake friction plate contact area measuring instrument for mining equipment and a manufacturing and measuring method thereof, which are used for solving the problem of inaccurate measurement of the brake contact area.
In order to achieve the above purpose, the invention adopts the following technical scheme:
the invention relates to a contact area measuring instrument for a brake friction plate, which comprises,
a contact area measuring instrument for a brake friction plate comprises,
the measuring sheet is of a sheet-shaped structure, the outermost layers at two sides are poly-p-phenylene terephthalamide fibers, the inner surfaces of the poly-p-phenylene terephthalamide fibers are covered with polyamide imide films, the edges of the poly-p-phenylene terephthalamide fibers and the polyamide imide films at two sides are provided with polyamide imide frames in a sealing way, the inner sides of the polyamide imide films are provided with two flow guiding silicon wafers, the opposite surfaces of the two flow guiding silicon wafers are provided with grooves, the grooves on the two flow guiding silicon wafers are arranged in a staggered way, the polyamide imide frames are provided with liquid guide holes, and a space between the two flow guiding silicon wafers is filled with measuring liquid;
the measuring column is a hollow structure, a sealing piston is arranged in the hollow structure, one end of the hollow structure is communicated with a liquid guide hole on a polyamide imide frame in the measuring sheet and is filled with measuring liquid, a carbon film resistor strip is laid on the inner wall of the hollow structure, the sealing piston and the resistor strip of the same type of measuring sheet have the same relative position, the sealing piston is flush with a preset printed datum reference line,
the measuring host comprises a high-precision AD conversion module, a singlechip and a display screen, wherein the high-precision AD conversion module is connected with the carbon film resistor strip, the high-precision AD conversion module is connected with an input bus of the singlechip, and the display screen is connected with an output bus of the singlechip.
Preferably, the device further comprises a measurement connecting line, one end of the measurement connecting line is connected with the measurement host, the other end of the measurement connecting line is provided with a measurement joint connected with the measurement column, the center of the measurement joint is a hole structure, one end of the measurement joint is a measurement column insertion opening, the hole structure is provided with two opposite photoelectric correlation sensors close to the measurement column insertion opening, the bottom of the hole structure is provided with a reflection type infrared sensor, two metal contacts are arranged between the reflection type infrared sensor and the photoelectric correlation sensors, and the metal contacts, the reflection type infrared sensor and the photoelectric correlation sensors are connected to the measurement host through the measurement connecting line.
Preferably, the front end of the measuring column is provided with an optical detection groove, the measuring column is provided with two metal rings a and b, one end of the carbon film resistor strip is connected with the metal ring a which is far away from the measuring sheet and is positioned on the measuring column through the metal rod a, the other end of the carbon film resistor strip is immersed into measuring liquid together with the metal rod b which is close to the metal ring b on the measuring sheet to form a carbon film resistor strip loop, the measuring column is inserted into a hole structure of the measuring joint, the metal ring a contacts a metal contact in the hole structure, the other end of the hollow structure of the measuring column is provided with an opening, and the reflective infrared sensor in the measuring joint emits infrared light towards the inside of the hollow structure of the measuring column and receives the reflected infrared light.
Preferably, the center of the metal ring a is provided with a metal rod b, the metal ring a and the metal rod a are fixed through spot welding after the piston is assembled, the metal ring b and the metal rod b are integrally formed and are injection-molded on the polyamide imide film frame, the metal rod a penetrates through the carbon film resistor strip, the metal rod a and the carbon film resistor strip are connected through conductive adhesive, and the resistance of the carbon film resistor strip is 10kΩ per millimeter.
Preferably, the volume of the hollow structure in the measuring column is larger than the maximum extrusion volume of the measuring liquid, the sealing piston in the hollow structure of the measuring column is positioned between the metal ring a and the metal ring b and is close to the metal ring b at the end of the measuring sheet, the sealing piston is made of a perfluoro ether material, the Shore hardness A is 15, and the hardness deviation is not more than 5%.
Preferably, the outside of measuring the post is provided with prevents slow-witted strip, is equipped with in the through-hole of measuring the joint and prevents slow-witted recess, measures the inside built-in identification resistance of connecting wire, and the type of measuring the measuring piece that the host computer accessible resistance discernment connecting wire matees only supports the measuring post access of same model measuring piece of measuring the joint of measuring the connecting wire of type, and different types measure post size is different, and is not general.
Preferably, the measuring solution is a sodium acetate solution, and is prepared by mixing 137.52 parts of GR grade anhydrous sodium acetate with 100 parts of pure water, wherein the conductivity of the pure water is not more than 1.3 mu S/cm at 25 ℃.
Preferably, the measuring host also comprises a power switch, a function button, a connecting wire interface, a wireless transmission module and a buzzer, wherein a connector is arranged at the end, connected with the measuring host, of the measuring connecting wire, the connector is inserted into the connecting wire interface, the singlechip is provided with an input bus and an output bus, the reflective infrared sensor, the photoelectric correlation sensor, the function button and the high-precision AD conversion module are connected with the singlechip through the input bus, and the display screen, the wireless transmission module and the buzzer are connected with the singlechip through the output bus.
A method for manufacturing a measuring instrument for the contact area of a brake friction plate comprises a manufacturing method of sodium acetate solution and a manufacturing method of a measuring plate,
1) The preparation method of the sodium acetate solution comprises the steps of heating pure water to boiling by using a polytetrafluoroethylene container through a heating plate, adding sodium acetate, stirring, continuously heating to 110 ℃, keeping the temperature for 10 minutes, cooling, and hermetically filling the space between two flow guiding silicon wafers by using a vacuum filling machine when the temperature is cooled to 20-30 ℃;
2) The manufacturing method of the measuring sheet comprises the steps that the weaving parameters of the poly-p-phenylene terephthalamide fiber are that warp yarns and weft yarns are respectively 20, the warp and weft densities are 108 multiplied by 48, the poly-p-phenylene terephthalamide fiber, the polyamide imide film and the UV adhesive with the viscosity lower than 5cs between the flow guiding silicon wafers are bonded, the bonding is carried out through 10N pressure, the measuring sheet is used for welding the composite film formed by the poly-p-phenylene terephthalamide fiber and the polyamide imide film and the polyamide imide frame together through an ultrasonic welding process, an ultrasonic welding head with the width larger than 2 times of frames is used for operation during welding, corresponding amplitude transformers are selected according to the difference of an ultrasonic welding machine, a near-field welding mode is selected, the following parameters are strictly followed for adjustment during welding, the welding triggering pressure is 70N, the welding frequency is 40 KHZ+/-0.5, the amplitude is 10 mu m, the welding time is 0.3s, the pressure maintaining time is 0.7s, the finished product after welding is subjected to random sampling detection of not lower than 5%, the pressure 1Mpa hydraulic testing machine is used for carrying out the pressure filling detection, the pressure maintaining time is 60s, no water leakage is avoided, and the ultrasonic welding machine can pass through the testing, and the frequency calibration, the calibration and the time and the welding are performed on the products are otherwise tested and tested.
The method for measuring the contact area of the brake friction plate comprises the following steps,
1) Inserting a measuring column of a measuring sheet into a measuring joint measured by a measuring connecting wire, inserting the joint of the measuring connecting wire into a host, starting the measuring host, and determining the model of the measuring sheet by the measuring host according to the identification resistance in the measuring connecting wire;
2) The reflection type infrared sensor arranged in the measuring joint works, transmits and receives a reflection signal, judges that the measuring column is inserted into the measuring joint after the reflection signal is measured, and performs the next measurement, otherwise, the display screen prompts: please insert a measurement column;
3) The photoelectric correlation sensor measures, when the photoelectric correlation signal is measured, the next measurement is carried out; otherwise, the screen prompts: the measuring liquid is invalid, and the measuring sheet is replaced;
4) Measuring initial resistance Ra self-checking of a carbon film resistor strip loop by a measuring host, measuring resistance at two ends of a metal contact by a singlechip in the measuring host through a high-precision AD conversion module, comparing the resistance with the resistance of a stored measuring sheet model, wherein the error is less than 0.5%, namely, the measuring host can pass the test and enter the next measurement, otherwise, reporting errors, if the resistance is infinite, reporting errors to prompt that the initial resistance is wrong, please check whether a piston is flush with a reference line, and if the resistance is different from the preset value of the model of the measuring sheet with the built-in model, the resistance is not infinite, reporting errors to prompt that the initial resistance is wrong, please check whether the measuring sheet is damaged;
5) After the self-inspection is completely passed, prompting 'self-inspection is passed, fixing a measuring sheet on a flashboard, and waiting for a measuring signal';
6) The brake is closed, the friction disc impacts the measuring disc, the flow guiding silicon wafer is crushed and compacted instantly, measuring liquid in the silicon wafer groove is extruded out from the liquid guiding port to enter the measuring column, the piston is pushed to move, resistance change of the carbon film resistor strip loop is caused, when the sudden change of the resistance of the carbon film resistor strip loop is detected to be 2 seconds after the carbon film resistor strip loop is stopped for the first time, the current resistance Rx of the carbon film resistor strip loop is recorded, and meanwhile, screen display is carried out: when the measurement is waiting for N seconds, counting down for ten seconds, starting the photoelectric correlation sensor to detect after the counting is finished, and when the photoelectric correlation signal is not detected, calculating the area of the friction plate in the subsequent step, otherwise, prompting that the switching-on signal is not measured and the measuring plate is damaged.
7) Extracting the current resistance Rx of the carbon film resistor strip loop, and entering an operation link;
8) The area pressed by the friction plate is calculated and output: friction plate area s= { [ (Ra-Rx)/(Rm ] ×d } = h×k,
wherein: s is the area of the friction plate,
ra: the initial resistance of the carbon film resistor strip loop,
rx is the current resistance of the carbon film resistor strip loop,
rm, resistance value of carbon film resistor strip per millimeter,
d, measuring the inner diameter of the column,
h, measuring the equivalent height of the liquid,
and k is a compensation coefficient for compensating errors caused by trace measurement liquid and the like which cannot be extruded in microscopic gaps after the internal structure of the measuring sheet (1) is subjected to impact pulverization compaction under the condition of standard braking force of the mine brake, wherein the compensation coefficient is used for correcting the coefficient by extruding the difference between an actual measurement value and a theoretical value after batch test of the batch of measuring sheets (1) through a standard pressure shape die.
The invention has the advantages that: compared with the traditional measuring technology, the precision is high, the full-automatic measuring is convenient to use, and the disposable measuring sheet can be stably put into the file for a long time after being used, so that the method can trace back and divide responsibility of accident files and provide evidence and identification basis of physical objects.
The measuring structure can directly read the measured data value, and the history measuring data can be reviewed;
the measuring piece can be used as consumable material to be matched with brakes of different specifications, is collected after single use, and is suitable for verification and inspection of a measuring structure.
The whole equipment is simple to operate, the result does not need to be checked and calculated again manually, and the measuring effect is high.
Drawings
Figure 1 is a block diagram of the meter of the present invention,
figure 2 is an exploded view of the measuring blade of the present invention,
figure 3 is a side partial block diagram of a measuring blade of the present invention,
figure 4 is a groove stagger structure diagram of the flow guiding silicon chip of the measuring chip of the invention,
FIG. 5 is a diagram showing the connection relationship between the measuring plate and the connecting column according to the present invention,
figure 6 is a cut-away view of a measuring column of the present invention,
figure 7 is a second cutaway view of the measuring column of the present invention,
figure 8 is a block diagram of the measurement connection line of the present invention,
figure 9 is a block diagram of the inside of the measuring column joint of the present invention,
figure 10 is a diagram of the external architecture of the measurement host of the present invention,
fig. 11 is a diagram of the measurement host circuit connection relationship of the present invention.
Reference numerals: the device comprises a measuring sheet 1, a poly (p-phenylene terephthalamide) fiber 11, a polyamide imide film 12, a polyamide imide frame 13, a flow guiding silicon wafer 14, a groove 15, a liquid guiding hole 16, a measuring column 2, a hollow structure 21, a piston 22, a carbon film resistor strip 23, a fool-proof strip 24, a fool-proof groove 25, a metal ring 261, a metal ring 262, an optical detection groove 27, a metal rod 281, a metal rod 282, a measuring connecting wire 3, a measuring joint 31, a hole structure 32, a measuring column inserting hole 33, a photoelectric correlation sensor 34, a reflecting infrared sensor 35, a metal contact 36, a host joint 37, a measuring host 4, a display screen 41, a power switch 42, a function button 43 and a connecting wire interface 44.
Detailed Description
The specific structure of the present invention will be further described below:
the invention relates to a contact area measuring instrument for a brake friction plate, which is structurally shown in figures 1-10 and comprises a replaceable measuring plate 1, a measuring column 2 connected with the measuring plate 1, a measuring connecting wire 3 and a measuring host. The measuring column is connected with a measuring host computer through a measuring connecting wire 3.
The above-described components in the present invention will be specifically described,
in the invention, as shown in fig. 2-4, the measuring sheet 1 is of a sheet-shaped structure as a whole, the outermost layers of two side surfaces are poly-paraphenylene terephthalamide fibers 2, the inner surfaces of the two poly-paraphenylene terephthalamide fibers are respectively covered with a polyamide imide film 12, and the thickness of the polyamide imide film is 0.08mm. The edge of the poly (p-phenylene terephthalamide) fiber and the polyamide imide film 12 on both sides are connected with the polyamide imide frame 13 in a sealing way, and the height of the polyamide imide frame 13 is 1mm. The spinning parameters of the poly (paraphenylene terephthalamide) fiber are as follows: the warp yarn and the weft yarn are respectively 20 branches, and the warp and weft density is 108 multiplied by 48. The paraphenylene terephthalamide fibers and the polyamideimide film 12 are connected to the polyamideimide frame 13 by ultrasonic welding.
Two flow guiding silicon wafers 14 are arranged on the inner side of the polyamide imide film 12, and the polyamide imide frame 13 and the two sides of the paraphenylene terephthalamide fibers and the polyamide imide film 12 wrap and seal the two flow guiding silicon wafers 14 to form a sealed structure cavity. Grooves 15 are formed in the opposite surfaces of the two flow guiding silicon wafers 14, and the grooves 15 on the two flow guiding silicon wafers 14 are arranged in a 90-degree staggered mode.
The diversion silicon wafer is preferably produced by a full-automatic DUV photoetching machine through a multi-layer exposure technology, wherein the thickness of an exposure layer is 20 microns, the angle of a triangular groove is 50 degrees, and the depth is 400 microns. For the diversion silicon chip used in the low-precision application place, an etching machine can also be used for production.
And (3) bonding the poly (p-phenylene terephthalamide) fiber, the polyamide imide film and the UV adhesive with the viscosity lower than 5cs between the flow guiding silicon chips, and crimping the mixture to be completely solidified by 10N pressure.
The polyamideimide frame 13 is provided with a liquid guide hole 16, and the space between the two flow guide silicon chips 14, the liquid guide hole and the piston, which are close to the measuring piece, is filled with measuring liquid.
The measuring solution is CH3COONa (sodium acetate) solution, and the specific solution is prepared by the following steps: the sodium acetate was 137.52 g GR grade anhydrous sodium acetate, 100 g pure water, and the pure water quality control required conductivity to be not more than 1.3. Mu.S/cm (25 ℃). The preparation process of the sodium acetate solution comprises the steps of using a polytetrafluoroethylene container as a heating container for pure water, heating to boiling by using a heating plate, adding sodium acetate, stirring, continuously heating to 110 ℃, and keeping the temperature for 10 minutes. And then cooling, and when the temperature is cooled to 20-30 ℃, using a vacuum filling machine to carry out closed filling to the space between the two flow guiding silicon wafers 14.
In the invention, a liquid guide hole on a polyamideimide frame 13 is connected with a measuring column 2 of a hollow structure 21, the structure is shown in fig. 5-7, a sealed piston 22 is arranged in the hollow structure 21, one end of the hollow structure 21 is communicated with a liquid guide hole 16 on the polyamideimide frame 13 in a measuring sheet 1, and a carbon film resistor strip 23 is laid on the inner wall of the hollow structure 21. The front end of the measuring column 2 is provided with an optical detection groove 27, the measuring column 2 is provided with two metal rings 261 and 262, one end of the carbon film resistor strip 23 is connected with a 316L metal ring 261 which is far away from the measuring sheet and is positioned on the measuring column through a metal rod 281, the other end of the carbon film resistor strip is immersed into measuring liquid together with a metal rod 282 which is close to the 316L metal ring 262 on the measuring sheet, the metal ring 26 contacts with a metal contact 36 in the hole structure when the measuring column 2 is inserted into the hole structure of the measuring joint 31, and the other end of the hollow structure 21 of the measuring column 2 is provided with an opening. The two metal rings 261 and 262 form a circuit measurement loop with the carbon film resistor strip 23 and the measurement liquid.
The volume of the hollow structure 21 in the measuring column 2 is larger than the maximum extrusion volume of the measuring liquid, the sealing piston 22 in the hollow structure 21 of the measuring column 2 is positioned between the two metal rings 261 and 262 and is close to the metal ring 261 at the end of the measuring sheet 1, the sealing piston 22 is made of a perfluoroether material, the Shore hardness A is 15, and the hardness deviation is not larger than 5%. The sealing piston is close to the metal ring at the inner side of the measuring column and has a distance of about 1mm, the metal ring 261 is provided with a metal rod 281 at the center, the metal ring 262 is provided with a metal rod 282 at the center, the metal rod 281 penetrates through the carbon film resistor strip 23, and the resistance of the carbon film resistor strip 23 is 10kΩ per millimeter.
The outside of measuring post 2 is provided with prevents slow-witted strip 24, and the inside built-in identification resistance of measuring connecting wire 3 measures the kind of measuring piece 1 that host computer 4 accessible resistance discernment connecting wire matees, and the measuring piece 1 is only supported to the model measuring connecting wire 3, and measuring post 2 inserts in measuring joint 31 even, and measuring post 2 of different models is different in size, and is not applicable.
The polyamide imide frame and the measuring column are formed by integral injection molding, the carbon film resistor strip which is matched with the measuring column and has smooth surface is embedded on the inner surface of the measuring column during injection molding, two metal rings made of 316L stainless steel are integrally injection-molded and embedded on the measuring column, metal rods penetrating through the centers of the metal rings are arranged in the metal rings, the metal rods in the metal rings close to the opening of the measuring column are movable metal rods, the metal rods are connected with the carbon film resistor strip through conductive adhesive, and the assembled metal rings are connected with the metal rods through spot welding; the other metal ring and the metal rod are positioned at one end close to the measuring piece and are integrally formed, the two metal rings and the measuring column are coaxial, but the inner metal rod is crossed at 90 degrees, and the position relationship is shown in fig. 6 and 7.
As shown in figures 8 and 9, one end of the measurement connecting wire 3 is connected with the measurement host 4, the other end is provided with the measuring joint 31, the center of the measuring joint 31 is of a hole structure, and a fool-proof groove 25 is arranged in a through hole of the measuring joint 31, so that the fool-proof strip 24 on a measurement column is ensured to be inserted into the joint angle of the measurement column correctly.
One end of the measuring joint 31 is a measuring column inserting opening 33, and the measuring column 2 is inserted into the measuring column inserting opening 33 to realize the connection of the measuring column inserting opening 33 and the measuring column.
The hole structure is provided with two opposite photoelectric correlation sensors 34 near the measuring column inserting opening 33, the bottom of the hole structure is provided with a reflection type infrared sensor 35, two metal contacts 36 are arranged between the reflection type infrared sensor 35 and the photoelectric correlation sensors 34, and the metal contacts 36 at the two positions are respectively matched with the positions of metal rings on the measuring column. The metal contact 36, the reflective infrared sensor 35 and the photo correlation sensor 34 are connected to the measurement host 4 through the measurement connection line 3. The measuring post is inserted into the measuring joint 31 and the metal ring is contacted with the metal contact to form a circuit path.
The reflective infrared sensor 35 in the measuring joint 31 emits infrared light into the hollow structure 21 of the measuring column 2 and receives the reflected infrared light. The photoelectric correlation sensor 34 determines whether a measuring column is inserted into the measuring joint 31 for the next operation.
The structure of the measuring host 4 is as shown in fig. 10-11, and the measuring host comprises a high-precision AD conversion module, a singlechip, a display screen, a power switch, a function button, a connecting wire interface, a wireless transparent transmission module and a buzzer which are connected with a carbon film resistor strip 23.
The high-precision AD conversion module is connected with the carbon film resistor strip 23, the connector of the measurement connecting wire 3 is inserted into the connecting wire interface on the measurement host 4, the reflection type infrared sensor 35, the photoelectric correlation sensor 34, the function button and the high-precision AD conversion module are connected with the singlechip through an input bus, the display screen, the wireless transmission module and the buzzer are connected with the singlechip through an output bus, and the wireless transmission module can be matched with external expansion equipment such as a thermal printer.
The measurement procedure of the present invention will be described below,
the invention relates to a method for measuring a contact area measuring instrument of a brake friction plate, which comprises the following steps,
1) Inserting the measuring column 2 of the measuring sheet 1 into a measuring joint 31 measured by a measuring connecting wire 3, inserting the joint of the measuring connecting wire 3 into a host, starting a measuring host 4, and determining the model of the measuring sheet 1 by the measuring host 4 according to the identification resistance in the measuring connecting wire 3;
2) The reflection type infrared sensor 35 arranged in the measuring joint 31 works, transmits and receives a reflection signal, and judges that the measuring column 2 is inserted into the measuring joint 31 after the reflection signal is measured, and then the next measurement is carried out, otherwise, the display screen prompts: please insert the measuring column 2;
3) The single chip microcomputer in the measuring host 4 measures the resistance of the two ends (initial resistance Ra of a carbon film resistor strip 23 loop) of the metal contact 36 through a high-precision AD conversion module, and compares the resistance with the resistance of the model of the measuring sheet at the storage side, the error is less than 0.5%, the test can be passed, the next measurement is carried out, otherwise, error reporting is carried out, if the resistance is infinite, error reporting prompts the initial resistance error, please check whether the piston 22 is flush with a reference line, if the resistance has different conditions from the preset value of the model of the measuring sheet 1 built-in the model, the initial resistance error is not infinite, and if the resistance has the condition different from the model of the measuring sheet 1 built-in, the screen error reporting prompts the initial resistance error, please check whether the measuring sheet 1 is damaged;
4) The photoelectric correlation sensor 34 performs measurement, and when a photoelectric correlation signal is measured, the next measurement is performed; otherwise, the screen prompts: the measuring liquid is failed, and the measuring sheet 1 is replaced;
5) After the self-inspection is completely passed, prompting 'self-inspection is passed, please fix the measuring sheet 1 on the flashboard, and waiting for a measuring signal';
6) The brake is switched on, the friction plate impacts the measuring plate 1, the measuring plate 1 is impacted and instantaneously pulverizes the flow guiding silicon wafers 14, the measuring liquid between the gaps of the flow guiding silicon wafers 14 can be extruded and enters the measuring column 2 from the liquid guiding port, and the measuring liquid in the measuring column 2 pushes the piston 22 to move;
7) When a sudden change in resistance is detected to 2 seconds after the first rest, the current resistance value Rx is recorded, and meanwhile, the screen display is carried out: while waiting for N seconds, counting down for ten seconds, starting the photoelectric correlation sensor 34 to detect after the counting is finished, and calculating the area of the friction plate when the photoelectric correlation signal is not measured, otherwise, prompting that the closing signal is not measured and the measuring plate 1 is damaged.
8) The area of the friction plate in compression joint is calculated: friction plate area s= { [ (Ra-Rx)/(Rm ] ×d } = h×k,
wherein: s, friction plate area, ra: the initial resistance of the carbon film resistor strip loop Rx is the current resistance of the carbon film resistor strip loop Rm is the resistance value of the carbon film resistor strip per millimeter, d is the inner diameter of a measuring column, h is the equivalent height of measuring liquid, and k is the compensation coefficient.
The initial resistance of the carbon film resistor strip loop is calibrated uniformly in factory, the initial resistance of the loop is calibrated by controlling the position of the current piston determined by the filling amount of the measuring liquid, an electrode at the tail end of the carbon film resistor strip and a 316L stainless steel measuring column immersed in the measuring liquid form a loop, the initial resistance Ra of the carbon film resistor strip loop of the same type of measuring sheet is ensured to be the same through factory quality control, when the carbon film resistor strip loop is closed, a pressed flow guiding silicon wafer is crushed instantly by huge impact force, the measuring liquid between the gaps of the flow guiding silicon wafer is extruded, and the piston is pushed to move. And obtaining the movement length of the piston by measuring the linear change of the resistance, and further calculating the area of the crimping area of the friction plate. The equivalent height of the measuring liquid refers to the theoretical height of the measuring liquid which can be extruded after the friction plate is switched on. The compensation coefficient is used for compensating errors caused by micro measuring liquid and the like which remain in microscopic gaps and cannot be extruded after the silicon wafer is extruded, pulverized and compacted by the friction plate, and is generally used for carrying out coefficient correction by extruding the difference between an actual measurement value and a theoretical value after batch testing of the batch of measuring plates through a standard pressure shape die.
The use and the preservation description of the measuring instrument are as follows:
before use, the measuring sheet is taken out from the package, whether the package is damaged, leaked and bent is checked, and the measuring sheet cannot be used when damaged.
After the inspection is correct, the main machine measuring line connector is connected with the measuring column, the main machine is started, the self-inspection is prompted, after the self-inspection is finished, the buzzer sends out drops, the measurement is prompted to start, and the main machine waits for closing. Failure of the self-test may prompt an error: 1. the measuring liquid fails to work by 2, the initial resistance is wrong, whether the piston is positioned at the initial position or not is checked, and whether the measuring wire ends are tightly connected or not is checked. If the connection of the measuring lines is confirmed to be free of problems, the measuring sheets with problems are replaced by new measuring sheets, and the returning and replacement processing is carried out on the measuring sheets with problems.
During the use, can use the sticky tape to measure piece edge with the consumptive material and be fixed in on the brake disc, the equipment of being surveyed should shut down this moment, and this measurement only is used for the static combined floodgate of mine fixed equipment to measure, and this instrument is researched and developed to the explosion-proof fixed equipment of mine application disk brake device characteristic that the most widely, when being used for other general purpose braking equipment, can't guarantee its measurement accuracy.
The type of the measuring sheet is selected according to the size of the friction sheet, and the area of the measuring sheet is generally 2-3 times larger than that of the newly purchased friction sheet, so that the friction sheet can not be pressed to the edge of the measuring sheet when the friction sheet is used.
Function selection: reading the used measuring plate friction plate area, checking historical measurement data and setting system time.

Claims (10)

1. A measuring instrument for the contact area of a brake friction plate for mining equipment is characterized by comprising,
the measuring sheet (1) is of a sheet-shaped structure, the outermost layers on two sides are poly-p-phenylene terephthalamide fibers (2), the inner surfaces of the poly-p-phenylene terephthalamide fibers (2) are covered with polyamide imide films (12), the edges of the poly-p-phenylene terephthalamide fibers on two sides and the polyamide imide films (12) are provided with polyamide imide frames (13) in a sealing mode, two guide silicon wafers (14) are arranged on the inner sides of the polyamide imide films (12), grooves (15) are formed in the opposite faces of the two guide silicon wafers (14), grooves (15) on the two guide silicon wafers (14) are arranged in a staggered mode, liquid guide holes (16) are formed in the polyamide imide frames (13), and measuring liquid is filled in the space between the two guide silicon wafers (14);
the measuring column (2) is a hollow structure (21), a sealing piston (22) is arranged in the hollow structure (21), one end of the hollow structure (21) is communicated with a liquid guide hole (16) on a polyamide imide frame (13) in the measuring sheet (1) and is filled with measuring liquid, a carbon film resistor strip (23) is laid on the inner wall of the hollow structure (21), the sealing piston (22) of the same type of measuring sheet (1) is the same as the resistor strip (23) in relative position, the sealing piston (22) is flush with a preset printed datum reference line,
the measuring host (4) comprises a high-precision AD conversion module, a single chip microcomputer and a display screen, wherein the high-precision AD conversion module, the single chip microcomputer and the display screen are connected with the carbon film resistor strip (23), the high-precision AD conversion module is connected with an input bus of the single chip microcomputer, and the display screen is connected with an output bus of the single chip microcomputer.
2. The brake friction plate contact area measuring instrument for mine equipment according to claim 1, further comprising a measuring connecting wire (3), wherein one end of the measuring connecting wire (3) is connected with the measuring host machine (4), the other end is provided with a measuring joint (31) connected with the measuring column (2), the center of the measuring joint (31) is of a hole structure, one end of the measuring joint (31) is of a measuring column inserting opening (33), the hole structure is provided with two opposite photoelectric correlation sensors (34) close to the measuring column inserting opening (33), the bottom of the hole structure is provided with a reflective infrared sensor (35), two metal contacts (36) are arranged between the reflective infrared sensor (35) and the photoelectric correlation sensors (34), and the metal contacts (36), the reflective infrared sensor (35) and the photoelectric correlation sensors (34) are connected to the measuring host machine (4) through the measuring connecting wire (3).
3. The brake friction plate contact area measuring instrument for mining equipment according to claim 2, wherein an optical detection groove (27) is formed in the front end of the measuring column (2), two metal rings a (261) and b (262) are arranged on the measuring column (2), one end of the carbon film resistor strip (23) is connected with the metal ring a (261) which is far away from the measuring plate and is located on the measuring column through a metal rod a (281), the other end of the carbon film resistor strip is immersed into measuring liquid together with a metal rod b (282) which is close to the metal ring b (262) on the measuring plate, a carbon film resistor strip loop is formed, the metal ring a (261) contacts a metal contact point (36) in the hole structure when the measuring column (2) is inserted into the hole structure of the measuring joint (31), the other end of the hollow structure (21) of the measuring column (2) is provided with an opening, and the reflective infrared sensor (35) in the measuring joint (31) emits infrared light towards the hollow structure (21) of the measuring column (2) and receives reflected infrared light.
4. A brake friction plate contact area measuring apparatus for mine equipment as defined in claim 3, wherein the metal ring a (261) is provided with a metal rod (281) at the center, the metal ring b (262) is provided with a metal rod b (282) at the center, the metal ring a (261) and the metal rod a (281) are fixed by spot welding after the piston is assembled, the metal ring b (262) and the metal rod b (282) are integrally formed and injection-molded on the frame of the polyamideimide film (12), the metal rod a (281) penetrates through the carbon film resistor strip (23), the metal rod a (281) is connected with the carbon film resistor strip (23) through conductive adhesive, and the resistance of the carbon film resistor strip (23) is 10kΩ per millimeter.
5. The gauge for measuring the contact area of a brake friction plate for mining equipment according to claim 4, wherein the volume of the hollow structure (21) in the measuring column (2) is larger than the maximum extrusion volume of the measuring liquid, the sealing piston (22) in the hollow structure (21) of the measuring column (2) is positioned between the metal ring a (261) and the metal ring b (262) and is close to the metal ring b (262) at the end of the measuring plate (1), the sealing piston (22) is made of a perfluorinated ether material, the shore hardness A is 15, and the hardness deviation is not larger than 5%.
6. The braking friction plate contact area measuring instrument for mining equipment according to claim 5, wherein foolproof strips (24) are arranged outside the measuring columns (2), foolproof grooves (25) are formed in through holes of the measuring joints (31), identification resistors are built in the measuring connecting lines (3), the measuring host (4) can identify the types of measuring plates (1) matched with the connecting lines through the resistors, the measuring joints (31) of the same type measuring connecting lines (3) only support the connection of measuring columns of the same type measuring plates, and the measuring columns (2) of different types are different in size and cannot be used universally.
7. The gauge for measuring the contact area of a brake pad for mining equipment according to claim 6, wherein the measuring solution is a sodium acetate solution, and is prepared by mixing 137.52 parts of GR-grade anhydrous sodium acetate with 100 parts of pure water, and the conductivity of the pure water is not more than 1.3 μs/cm at 25 ℃.
8. The measuring instrument for the contact area of the braking friction plate for the mining equipment according to claim 7, wherein the measuring host (4) further comprises a power switch, a function button, a connecting wire interface, a wireless transmission module and a buzzer, a connector is arranged at the connecting end of the measuring connecting wire (3) and the measuring host (4), the connector is inserted into the connecting wire interface, the singlechip is provided with an input bus and an output bus, the reflective infrared sensor (35), the photoelectric correlation sensor (34), the function button and the high-precision AD conversion module are connected with the singlechip through the input bus, and the display screen, the wireless transmission module and the buzzer are connected with the singlechip through the output bus.
9. A method for manufacturing the gauge for the contact area of a brake friction plate according to claim 8, characterized by comprising a method for manufacturing a sodium acetate solution and a method for manufacturing a gauge,
1) The manufacturing method of the sodium acetate solution comprises the steps of heating pure water to boiling by using a polytetrafluoroethylene container through a heating plate, adding sodium acetate, stirring, continuously heating to 110 ℃, keeping the temperature for 10 minutes, cooling, and when the temperature is cooled to 20-30 ℃, using a vacuum filling machine to fill a space between two flow guiding silicon wafers (14) in a closed mode;
2) The manufacturing method of the measuring sheet comprises the steps that the spinning parameters of the poly-p-phenylene terephthalamide fiber (2) are warp yarns and weft yarns respectively, the warp and weft densities are 108 multiplied by 48, the poly-p-phenylene terephthalamide fiber (2), the polyamide imide film (12) and the UV adhesive with the viscosity lower than 5cs between the diversion silicon wafers (14) are bonded, the poly-p-phenylene terephthalamide fiber is subjected to pressure welding to be completely solidified through 10N, the measuring sheet (1) welds the composite film consisting of the poly-p-phenylene terephthalamide fiber (2) and the polyamide imide film (12) and the polyamide imide frame (13) together through an ultrasonic welding process, an ultrasonic welding head with the width larger than 2 times of frames is used for operation, a corresponding amplitude transformer is selected according to the difference of an ultrasonic welding machine, a near-field welding mode is selected, the following parameters strictly when welding is performed, the welding trigger pressure is 70N, the welding frequency is 40KHZ (+ -0.5), the amplitude is 10 mu m, the welding time is 0.3s, the pressure maintaining time is 0.7s, the finished product after welding is subjected to random detection, the pressure is not lower than 5%, the pressure maintaining time is 1Mpa is used, the hydraulic pressure is used for detection, the time is not needed, the calibration and the time is tested, the ultrasonic welding is carried out, the time is tested, and no water leakage is tested, and the quality is tested, and no time is used.
10. A method of measuring a brake pad contact area gauge according to claim 8, comprising the steps of,
1) inserting a measuring column (2) of a measuring sheet (1) into a measuring joint (31) measured by a measuring connecting wire (3), inserting the joint of the measuring connecting wire (3) into a host machine, starting a measuring host machine (4), and determining the model of the measuring sheet (1) by the measuring host machine (4) according to the identification resistance in the measuring connecting wire (3);
2) The built-in reflection type infrared sensor (35) of the measuring joint (31) works, transmits and receives a reflection signal, and judges that the measuring column (2) is inserted into the measuring joint (31) after the reflection signal is measured, and then the next measurement is carried out, otherwise, a display screen prompts: please insert the measuring column (2);
3) The photoelectric correlation sensor (34) is used for measuring, and when a photoelectric correlation signal is measured, the next measurement is carried out; otherwise, the screen prompts: the measuring liquid is failed, and the measuring sheet (1) is replaced;
4) Measuring initial resistance Ra of a carbon film resistor strip (23) loop by a measuring host (4), measuring resistance at two ends of a metal contact (36) by a singlechip in the measuring host (4) through a high-precision AD conversion module, comparing the resistance with the resistance of a stored measuring sheet model, wherein the error is less than 0.5%, and then, the next step of measurement can be carried out through a test, otherwise, error reporting is carried out, if the resistance is infinite, error reporting prompts that the initial resistance is wrong, if the resistance is flush with a reference line, a piston (22) is checked, if the resistance is different from a preset value of the model of the built-in measuring sheet (1) and is not infinite, screen error reporting prompts that the initial resistance is wrong, and if the measuring sheet (1) is damaged, the initial resistance is checked;
5) After the self-inspection is completely passed, prompting 'self-inspection is passed, and fixing the measuring sheet (1) on the flashboard to wait for a measuring signal';
6) The brake is closed, the friction disc impacts the measuring disc, the flow guiding silicon wafer is crushed and compacted instantly, measuring liquid in the silicon wafer groove is extruded out from the liquid guiding port to enter the measuring column, the piston is pushed to move, resistance change of the carbon film resistor strip loop is caused, when sudden resistance change of the carbon film resistor strip (23) loop is detected to be 2 seconds after the first standstill, the current resistance Rx of the carbon film resistor strip (23) loop is recorded, and meanwhile screen display is carried out: waiting for N seconds during measurement, counting down for ten seconds, starting a photoelectric correlation sensor (34) to detect after the counting is finished, and calculating the area of a friction plate in the following step when a photoelectric correlation signal is not detected, otherwise, prompting that a closing signal is not measured and a measuring plate (1) is damaged;
7) Extracting the current resistance Rx of the carbon film resistor strip loop, and entering an operation link;
8) The area pressed by the friction plate is calculated and output: friction plate area s= { [ (Ra-Rx)/(Rm ] ×d } = h×k,
wherein: s is the area of the friction plate,
ra: the initial resistance of the carbon film resistor strip loop,
rx is the current resistance of the carbon film resistor strip loop,
rm, resistance value of carbon film resistor strip per millimeter,
d, measuring the inner diameter of the column,
h, measuring the equivalent height of the liquid,
and k is a compensation coefficient for compensating errors caused by trace measurement liquid and the like which cannot be extruded in microscopic gaps after the internal structure of the measuring sheet (1) is subjected to impact pulverization compaction under the condition of standard braking force, and is generally used for carrying out coefficient correction by extruding the difference between an actual measurement value and a theoretical value after batch test on the measuring sheet (1) through a standard pressure shape die.
CN202210099652.XA 2022-01-27 2022-01-27 Contact area measuring instrument for braking friction plate for mining equipment and manufacturing and measuring method Active CN114459340B (en)

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Publication number Priority date Publication date Assignee Title
DE102009010890A1 (en) * 2009-02-27 2010-09-02 Siced Electronics Development Gmbh & Co. Kg Method for determining contact area of probe fitted on conductor or semiconductor material, involves obtaining contact area of probe and insulating layer, and measuring capacitance of contact area
CN102519865A (en) * 2011-11-03 2012-06-27 西安交通大学 Variable capacitance-based sensor for corrosion monitoring of steel structure surface and manufacturing method thereof
CN102759465A (en) * 2011-04-29 2012-10-31 北京联合大学生物化学工程学院 Lead ion enrichment material preparation process
CN103745884A (en) * 2014-01-13 2014-04-23 江苏现代电力科技股份有限公司 Intelligent integration high-voltage alternating current contactor
CN104538939A (en) * 2014-12-08 2015-04-22 国家电网公司 Wind-power-contained isolated grid running outgoing line reclosing method adapting to formation of three-phase tripping operation
CN110469808A (en) * 2018-05-12 2019-11-19 成都市坤盛电子科技有限公司 A kind of household heating height-regulating lamp

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102009010890A1 (en) * 2009-02-27 2010-09-02 Siced Electronics Development Gmbh & Co. Kg Method for determining contact area of probe fitted on conductor or semiconductor material, involves obtaining contact area of probe and insulating layer, and measuring capacitance of contact area
CN102759465A (en) * 2011-04-29 2012-10-31 北京联合大学生物化学工程学院 Lead ion enrichment material preparation process
CN102519865A (en) * 2011-11-03 2012-06-27 西安交通大学 Variable capacitance-based sensor for corrosion monitoring of steel structure surface and manufacturing method thereof
CN103745884A (en) * 2014-01-13 2014-04-23 江苏现代电力科技股份有限公司 Intelligent integration high-voltage alternating current contactor
CN104538939A (en) * 2014-12-08 2015-04-22 国家电网公司 Wind-power-contained isolated grid running outgoing line reclosing method adapting to formation of three-phase tripping operation
CN110469808A (en) * 2018-05-12 2019-11-19 成都市坤盛电子科技有限公司 A kind of household heating height-regulating lamp

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