TW509786B - Micro-force measurement device with all coil magnetic-force balanced structure - Google Patents

Abstract

The present invention provides a micro force measurement device with all coil magnetic-force balanced structure, which utilizes the magnetic-force to measure the micro force (lower than 1mN). By applying current to the precisely designed coil structure in the present device, a radial magnetic field is generated to produce an axial magnetic repulsive force to the current on the weighting coil. This force is proportional to the current on the weighting coil, thereby forming a magnetic force capable of being tuned by current. When external force is asserted on the supporting mechanism of the present device, a micro shift is generated, which is sensed by a differentially capacitive displacement sensor. Then, a control circuit feeds back a current to the weighting coil to produce a magnetic force to counterbalance the external force. Therefore, it is able to measure the externally asserted micro force by the positive proportional relation between the generated magnetic force and current.

Description

509786 V. Description of the invention (l) Background of the invention The present invention relates to a precision measurement device, especially a coil magnetic floating type micro-force measurement device, which uses a circuit to adjust the measurement range and resolution required to correct and measure Micro force measurement, in which the measurement range and resolution are directly proportional to the current of the circuit. Integrate micro-force technology with nanometer metrology (such as atomic force microscopic technique) to measure nanometers

The surface features and mechanical properties of the rice structure (narostructure), such as the surface atomic distribution, micro hardness, and micro Young's coefficient. The key to its technology lies in measuring instruments such as the output power of Pr0be, or microstrain gauges of the micro-electromechanical (MEMS) process, such as 0n1Crostrainometer, which must be quantitative and controlled in order to change the micromechanical properties. Oxygen is between 1 mN, and the necessary data is' there is more power, but currently there are no suitable instruments to achieve this. Other precision devices are used for calibration, so 'an object of the present invention is a measuring device, which uses a circuit to adjust the place: two kinds of coil magnetic levitation type micro force I positive and measuring micro force', where measurement; range = range and resolution, to Sugi is directly proportional. And the resolution is the power of the circuit. Another object of the present invention is to improve the application of electromagnetic principles in measuring micro-force;

The present invention provides a coil obstruction •• A radial magnetic field generates I f / type imitation force just installed t section Yang •, 丨 Λ is used to generate a “you 1 set”, such as clothing, temperature and other environmental factors. To the lowest. t can include materials and machines-for very high summer, ’heavy coils, used to match the housing when conducting-radial radial port 5H radial magnetic field, to: feedback

509786 V. Description of the invention (2) Buoyancy; a load-bearing mechanism to withstand the micro-force to be measured; a set of capacitive displacement sensors for measuring one of the micro-forces to be measured relative to the original of the force-bearing mechanism The displacement of the point position is used to adjust a feedback current when the feedback magnetic buoyancy and the micro force to be measured are equal; a control circuit is used to measure and correct the micro force to be measured according to the feedback current. Going back, using the measurement range and resolution is proportional to the current provided to the weight coil in the control circuit, the invention can achieve the measurement range and resolution required by the circuit adjustment to correct and The purpose of measuring micro force. In addition, when measuring micro-force, the present invention can also minimize environmental influence factors such as materials, temperature, and temperature. For example, in an atomic force pin or micro-strain needle, the present invention can be used to correct the relationship between the strain force and the force, and the control and measurement of the micro-force can be transferred to the measurement program. Second, the best measurement effect can be obtained. In order to make the above and the present invention easy to see, a simple illustration is shown below. Special features, advantages, and advantages can be more clearly shown below. ： 1 Ή 口 八 'detailed drawing shows a schematic diagram of the micro-force measuring device of the present invention; shows the block diagram of the control circuit in the figure; and "the figure shows the radial magnetic field generating device in the figure [symbol description] 1 ~ Radial magnetic field generator

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2 ~ weight lifting coil 3 ~ support mechanism 4 ~ flexible spring 5 ~ force bearing mechanism 6 ~ capacitive displacement sensor 7 ~ control circuit 8 ~ drive circuit 9 ~ analog / digital circuit 1 0 ~ microprocessor 11 ~ current supply Device 1 2 ~ precision series resistor 1 3 ~ coil supporting mechanism 1 4 ~ detailed description of the best embodiment of the coil assembly. Figure 1 is the micro-force measuring device of the present invention. In the first figure, the f-device-, -weight coil ⑴,

A dynamic valley-type displacement sensor (6) and a control circuit (7). As shown in Figure i, the load bearing mechanism (5) is connected to the support mechanism (3) via a flexible spring sheet (4). The combination of the flexible spring sheet (5) is easy to make the load bearing mechanism (5) only move up and down. Displace in a straight line without causing lateral displacement. The two sides of the load-bearing mechanism (5) monitor its position with a differential capacitive displacement sensor (6), and a ring-shaped weight lifting coil (2) is connected below. Weightlifting coils (2) are suspended from a radial magnetic field generating device

0729-7241TWF; 07900013; Sue.ptd Page 7 509786, Description of Invention (4) (1) Above the groove, the radial magnetic field produces a range of dream movement, providing a radially distributed magnetic η: heavy coil ⑺ capacitance Displacement sensor ⑹, weight lifting coil ^ control circuit ⑺ is responsible for the signal reading and line drive (2) and field generating device-Figure 2 is a schematic diagram of the control circuit of Figure 1. . The processor must first send a signal to the drive circuit to output the drive to the capacitive displacement sensor (6a, 6b) for measurement. For example, when the micro-force P to be measured is applied to the load bearing mechanism from top to bottom, the mechanism (5) and its weight lifting coil (2) are displaced downward together. This displacement is electrically: type displacement sensing 11 (6a, 6b) Measured, and output a non-zero proportional electric I to the control circuit (7). At this time, in the control circuit (7), j0), a microprocessor (10) calculates a feedback current value, and then causes the current source [la] to output the feedback current to the weight lifting coil (2). The other current source (iib) provides a fixed current to the radial magnetic field generating device (1), so that it generates a fixed directional magnetic field, and the feedback current that surrounds the weightlifting coil generates an electromagnetic force with this fixed magnetic field (Lorentz Force), the direction of the acting force is upward, so that the force mechanism (5) and the weight lifting coil (2) are lifted upward together to reduce the displacement. The second amount of displacement was detected by the capacitive displacement sensor (6a, 6b), and the feedback current was corrected again, and iteratively repeated until the displacement returned to zero. At this time, the flexible spring (5) returned to Before the application of p, the micro force P is equal to the magnetic force between the coils, and the micro force can be measured by the feedback current value $. This current value is measured by the precision series resistor (丨 2), and then the analog / digital circuit (9) is input to the microprocessor (10), and the micro force is calculated and displayed.

juy / δ〇 5 Invention description (5) Measured value. The principle of electromagnetic field is derived from the principle of radial magnetic field and weight lifting coil ^ = πΟηΙΒ, where D is the average weight of the weight lifting coil (2) and the current on the weight lifting coil (2), B: radial = magnetic ίβΐΓ / (1) The radial average magnetic field produced. As shown in Figure 3, 彳 ^ 磁 ％ B 疋 is synthesized from the magnetic field vectors of four sets of toroidal coils (丨 4) to form a two-way (" Μη: ^ ί〇η) ° (Λ 'coil is generated in the radial magnetic field Inside the ring-shaped concave sample (not shown) of the device 。. The direction of the current in the toroidal coil (14) is shown in Figure ΐ. The value of the magnetic field can be calculated by the formula B = Theoretical and accurate calculations are between 12 蛊: Λ'Λ: coil design related, n 'is a toroidal coil (the number of rents of 圈: m turns (the current value on ⑷, & is the second and upper two coils =. Substitute B) Then, the magnetic force (Mnmw / t 1 after the feed balance is equal to the external force p to be measured, the mouth is opposite; rc = rWww: 〇rV ^ hanging number, /, the early position is N / A. C only contains the current (I It has nothing to do with the nature of the material. It can be directly calculated from the public ten 呌 # /, negative degree ⑶ and ㈧, Danhu Jinha, Tengshi Shizhuang class calculation, or use standard weights to pass Lili drought to the present, Reconverted to C. This device is different from electronic balances because no magnetic material is used as the magnetic field source. Therefore, the feedback of the magnetic material, w_, and Syria makes the position of the load bearing mechanism m effective. It should be related to the retardation effect; and because of the influence of the mechanical strain of the sheet (4), you can do it again and again [the spring constant C is proportional to the current 丨, which is proportional to this dream. The above formula shows that the device can According to the magnitude of the micro force to be measured

509786 V Description of the invention (6) and change I to adjust the device to the most suitable measurement range. The characteristics of this split are linear, the measurement range and resolution can be adjusted by the circuit, no hysteresis, no temperature compensation is required, and it can be directly traced back to the basic quantity (current, length). A design example is used to illustrate the effectiveness of the present invention. When .7, D2 5: 5 cm, n2 20, η '= 20 0, I ,: = 〇 · ia, a = i cm, we can get C as 70 // N / A, if the current supply of weightlifting coil (2) is-commonly used current source: output range 2 0 ~ 2 A, resolution = 0 ·; [ma, then the correction range is 0 ~ 140 #N, resolution is 7 nN. If you want to increase the school circumference by 10 times: 0 ~ 1400 / zN, you can increase the current Γ to! Α, direct solution: the rule is 70 nN. However, this example is only a preferred embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. If equal changes and modifications are made in accordance with the present invention, 1 is the patent scope of the present invention. The forces are balanced from top to bottom. The electromagnetic force is Lorentz ☆, the current (I,) is generated by two forces from the bottom to the upper circle to generate local radial magnetism; The J-fixed toroidal coil structure uses a flexible spring to force the Lorentz force upward. Bearing force and its displacement, when Ui; and :: the electromagnetic force of the differential capacitive displacement rigidity device II and ", become public opinion, the force reaches the same level, this; the force ', and this force follows ::; The change of the magnetic levitation __ under the output of 10 cores is linear and adjustable. 509786 V. Description of the invention (7) The resolution and range are suitable for precision correction. The present invention does not use magnetic materials, avoids insufficient resolution, lack of variation with temperature, etc., and is different from the principle and structure of electronic balances. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Anyone who is familiar with this technology can make changes and decorations without departing from the spirit and scope of the present invention. The scope of protection shall be determined by the scope of the attached patent application.

0729-7241TWF; 07900013; Sue.ptd Page 11

Claims (1)

509786 VI. Scope of patent application1. A coil magnetic levitation type micro force measuring device, including: a .: a magnetic field generating device 'for generating-radial magnetic field; for generating-feedback magnetic buoyancy; A load-bearing machine connected to the weight-lifting coil, 目, and female τ to measure the micro-force; knife stack structure, with-platform to withstand a set of capacitive displacement sensors, using one of L7 denier and Japan 丨 # β relative to The origin of the load bearing mechanism is 2 = 3 when the magnetic buoyancy generated by the micro-force measurement is equal to the micro-force to be measured. The feedback circuit is a feedback circuit. f ，, measure micro-force. 夂 Feed current to measure and correct the problem. 2. If the coil magnetic levitation type MH h θ is set in the first patent application range, where the special magnetic type of the radial magnetic field generating device is: supporting force Measuring the coil-shaped coil and a current source to form the radial magnetic field 1. Use four sets of coils. 3. For example, the coil set of the first scope of the patent application, where the norm of the origin position of the load bearing mechanism / Within the measuring range of the force / testing displacement sensor. 糸 洛 在Coil type magnetic coil levitation force θ, B | L of the first scope of the patent application of the capacitive type. Among them, the bearing mechanism is characterized in that: an elastic sheet is installed to connect the support mechanism and one to connect the plane A and °. The lifting: the coil makes the load-bearing mechanism and the weight-lifting: ring c operate, wherein the group of capacitive displacement sensors = ^ force-mounted rigid sensors for differential displacement measurement. : Have a pair 0729-724nW; 07900013; Sue.ptd Page 12 509786 6. The scope of the patent application is set 6. If the coil magnet of the first scope of the patent application is applied, the control circuit further includes: a sub-type micro force test device-the first-analog / A digital circuit for processing the output signal of the motion sensor and generating a digital signal from :, and an electric valley type processor for outputting two current signals according to the digital wheel: the current signal; A first current supply is fed back to output a second current supply according to the inverse feedback current to the weight coil. The second current supply is used to provide a field generating device, which generates a solid radial magnetic field. 2 ^ to the feedback current in the magnetic coil are mutually $, to obtain the feedback = a precision resistance of the weight line, connected to the first current supply pollution, '^ micrometric force equal to the magnetic levitation force, the amount Measure this 2; wait for the voltage at 5 Hz; ϋ ° the corresponding two second analog / digital circuits of the feedback current, which are used to process the measured voltage and enter the processing results into the microprocessor, calculate the ' Measurement. Λ #It is not necessary to measure the micro force 7. If the coil magnetic levitation type micro force measuring device of item 6 of the patent application scope, the control device further includes a driving circuit (driving cir cu) connected to the capacitive displacement sensing of the 5th Hai group Device for driving the group of capacitive displacement sensors. 8 A coil magnetic levitation type micro-force measuring device, including a support mechanism having a groove portion; a radial magnetic field generating device having a ring-shaped groove portion and a ring-shaped groove portion 0729-7241TWF; 07900013; Sue.ptd Page 13 ^ 09786 VI. Scope of patent application _ Groove j 2: Two pairs of coils are used to generate a weight lifting coil, which is suspended in the annular groove; I to the market; a load-bearing mechanism, has a plurality of flexible springs,-two platforms connected to the two sides of the body, wherein the use of; the body and the top of the groove portion connected to the body and the support mechanism respectively The ends of one of the several flexible springs are respectively connected to the upper plane of the weight coil; one of the group of capacitive displacement sensors on the 5H platform is suspended above and below one side of the platform; Another flat control circuit is connected with a conductive element, the weight lifting coil and the group of capacitive displacement sensing ^ ° magnetic field generating device 9g = coil magnetic field of the patent application No. 8, '式 堂, +' The radial magnetic field generating device uses a four-core strict measurement current source to constitute the radial magnetic field. 、 A ^ -shaped coil and a set of 10. If the coil magnet of item 8 of the scope of the patent application, the plurality of flexible springs is a type shout force measuring device 1 1 · If the number of flexible springs of the patent application scope . Among them, the control circuit enters the first -8;:; circle magnetic levitation type micro force measurement and installation of a first analog / digital circuit, which has an input terminal connected to the group of electrical terminals 4, 刖, and an output terminal from the group Capacitive displacement sensing: J: used to receive and process signals; output k 7 tiger and generate a digital output a microprocessor, with a first output terminal and a second output terminal, 钤 —the second input terminal, The output of an analog / digital circuit minus an input connected to the first to receive the digital wheel-out signal to count 0729-7241TW; 07900013; Sue. Ptd Page 14 509786 6. Calculate the scope of patent application and output a feedback A current signal; a first current supply having an input terminal and an output terminal, the coughing terminal is connected to the output terminal of the microprocessor, and is used to output according to the connected = feedback electric muscle k number-the feedback current to the Weightlifting coil; Cry II second current supply device has an input terminal connected to an output terminal of the micro-processor = for receiving a command from the microprocessor to provide a magnetic field generating device [make it generate Fixed path Magnetic field: force = feed current interaction, so that the micro force to be measured and the weight line; circle: used for the output end of the first current supply and the iii to make the micro force to be measured and the maglev by 丄 = at / to The corresponding voltage of the feedback current when the force is equal to Γ; the two input terminals are respectively connected to the precision input signal and an output terminal, the voltage on the resistor, the output terminal is connected to ^ to measure the precision fruit to the In the microprocessor, it is calculated and displayed; = used: output junction 12. If the scope of patent application is the first! !! The coil magnetism of the item / the measured value. "The control device further includes a wire-turn magnetic drive type two micro-force measuring circuit", which has an input terminal and a round-out circuit (drlving one of the third output terminals of the microprocessor) for connecting 5 Hairen The wheel-in end is connected to the set of capacitive displacement sensors for two orders, and the output end drives the set of capacitive displacement sensors. X 康 一 command to drive