Metal wire resistivity measuring instrument

Abstract

The utility model provides a metal wire resistivity measuring instrument, which belongs to the technical field of resistivity detection, and mainly comprises a detection circuit for detecting the resistance of a metal wire, and also comprises a fixed frame and a movable frame which are used for clamping the metal wire to be measured, the fixed frame is fixed, the movable frame can linearly move along a guide rod with scales, and the guide rod is connected with the detection circuit. When the movable frame clamps one end of the metal wire to move linearly away from the fixed frame, the metal wire is straightened, and the length of the straightened metal wire can be directly read according to the scales on the guide rod; the detection circuit can measure the resistance of the metal wire. The metal wire resistivity measuring instrument can quickly measure the length of the metal wire, so that the length can be substituted to calculate the resistivity, and the measurement is more convenient and reliable.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of resistivity measurement, especially to the measurement equipment of wire resistivity. BACKGROUND

[0002] At present, the measurement principle of the resistivity of metal wire in the laboratory mainly relies on the resistivity formula: R = pL / S, wherein p is the resistivity, L is the length of the metal wire, and S is the cross-sectional area of the metal wire. Therefore, the resistivity can be calculated by measuring the resistance, cross-sectional area and length of the resistance wire, which is the basic principle of measuring the resistivity of the metal wire. In the experimental steps of measuring the resistivity of the metal wire, the voltage and current at both ends of the corresponding metal wire are usually measured by using the voltammetry method, so as to obtain the resistance value. For measuring the length L and diameter D of the metal wire, the length is measured by using a ruler, and the diameter is measured by using a screw micrometer, so as to calculate the required cross-sectional area, that is, the calculation formula of the cross-sectional area S is S = pD2 / 4.

[0003] The existing measurement equipment is not convenient for measuring the length of the metal wire. Because the metal wire is relatively thin and soft, it must be straightened before measurement to obtain a relatively accurate length measurement value, so it is necessary to cooperate with two people, and the measurement is very inconvenient. In addition, for the diameter of the metal wire, the measurement is more complicated, and the use of the screw micrometer needs to be very skilled, and the metal wire should not be bent locally during clamping, so the measurement efficiency is lower. UTILITY MODEL CONTENTS

[0004] The utility model aims at providing a kind of wire resistivity measuring instrument to solve the technical problem that it is inconvenient to measure the resistivity of metal wire in prior art.

[0005] To achieve the above-mentioned purpose, a kind of wire resistivity measuring instrument is adopted in the utility model, which includes a detection circuit for detecting the resistance of metal wire, and a fixed frame and a movable frame for clamping the metal wire to be measured. The fixed frame is fixed, and the movable frame can move linearly along a guide rod with scales. When the movable frame clamps one end of the metal wire away from the fixed frame and moves linearly, the metal wire is straightened, and the length of the metal wire when straightened can be directly read according to the scales on the guide rod.

[0006] The detection circuit is a circuit for measuring resistance by voltammetry, which is connected to both ends of the metal wire to obtain the resistance of the metal wire.

[0007] Further, the fixed frame and the movable frame are both provided with clamping components, which include a circular main body and a planar threaded disc coaxially and rotatably arranged in the main body, one end of the planar threaded disc is coaxially fixed with a conical gear ring, the conical gear ring is engaged with an adjusting bevel gear rotatably arranged in the side wall of the planar threaded disc; a plurality of slide columns are annularly arranged on the other end of the planar threaded disc, each slide column is connected with the planar threaded disc through a planar threaded pair, and the ends of all the slide columns close to each other are used for extruding the end of the metal wire to clamp the end of the metal wire.

[0008] Further, the ends of the slide columns close to each other are fixed with arc-shaped pressing plates, which are used for pressing the end side wall of the metal wire from the radial direction of the metal wire.

[0009] Further, the guide rod is horizontally fixed on a pair of left and right arranged support frames, and a rotatable lead screw is also arranged on the support frame in parallel with the guide rod, the movable frame is threadedly connected with the lead screw, and the guide rod is axially and slidingly connected with the movable frame.

[0010] Further, a vertical limiting baffle is fixed on one side of the movable frame and the fixed frame, and the limiting baffle is used for abutting against the end surface of the metal wire, the bottom end of the limiting baffle on the movable frame is connected with an indicating needle, and the indicating needle is used for pointing to the corresponding scale on the guide rod when the movable frame moves horizontally.

[0011] Further, one end of the lead screw is connected with the main shaft of the motor through an overload component, and the overload component makes the main shaft relatively slip and disengage from the transmission connection with the lead screw when the torque on the lead screw is greater than a set torque.

[0012] Further, the overload component includes a socket cover fixed on the end of the lead screw and a plug boss fixed on the end of the main shaft, the plug boss is axially inserted into the socket cover and is axially and elastically extruded connected with the inner wall of the socket cover through an elastic element, and when the metal wire is straightened, the movable frame cannot continue to move forward, so that the plug boss relatively slips with the socket cover by overcoming the elastic force.

[0013] Further, the end of the elastic element is connected with a sliding disc, and the sliding disc is extruded and contacted with the inner wall of the socket cover;

[0014] Further, a locking cover is rotatably sleeved on the main shaft, the locking cover is threadedly screwed on the outer side wall of the socket cover, and the plug boss is pushed towards the elastic element through a plurality of jacks.

[0015] Further, the jacks are arranged in parallel with the main shaft and are annularly arranged around the main shaft.

[0016] A disc spring is further arranged between the locking cover and the end face of the socket cover, and the disc spring is always in an axial compression state.

[0017] The utility model discloses a wire resistivity measuring instrument, the detection equipment of this utility model adopts the movable frame with the wire end part movement, until straightening, directly get the length value of wire from the corresponding guide post scale, and the measurement is very convenient, and the accuracy is higher, and at the same time, still specially set clamping part, the end part of wire is clamped quickly, and the change amount of the detection value of infrared distance measuring element is utilized, and the known specific diameter value of specific wire is supplemented, and the diameter size of wire can be quickly obtained, can not use the spiral measuring appearance, and the diameter measurement also becomes more convenient, thereby further improve the measurement efficiency of wire resistivity. BRIEF DESCRIPTION OF DRAWINGS

[0018] The drawings needed to be used in the following embodiment or prior art description will be briefly introduced, and the drawings in the following description are only some embodiments of the utility model, and not represent all specific structures or principles.

[0019] Figure 1 It is the whole structure schematic diagram of the utility model;

[0020] Figure 2 It is a main view structure diagram of clamping part;

[0021] Figure 3 It is the side view of the installation structure of slide column;

[0022] Figure 4 It is a structure schematic diagram of overload component;

[0023] Figure 5 It is a connection structure diagram of detection circuit;

[0024] Figure 6 It is a mounting structure schematic diagram of infrared distance measuring element relative to slide column.

[0025] In the drawing, fixed frame 1, movable frame 2, guide rod 3, clamping part 4, main body 401, plane screw plate 402, adjusting bevel gear 403, slide column 404, pressing sheet 405, infrared distance measuring element 406, support frame 5, lead screw 6, limit baffle 7, overload component 8, socket cover 801, plug-in boss 802, elastic element 803, sliding disc 804, top pin 805, locking cover 806, motor 9, indicating needle 10, wire to be measured 11, main shaft 12, disc spring 13, power supply 14, voltmeter 15, ammeter 16. DETAILED DESCRIPTION

[0026] The embodiments of the present application are described below in detail, examples of the embodiments are shown in the drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0027] Please refer to Figure 1 The metal wire resistivity measuring instrument proposed in the embodiment, like the traditional metal wire resistivity detection method, first detects the resistance value of the metal wire, i.e. must include a detection circuit for detecting the resistance of the metal wire, and usually uses the voltammetry method to measure the resistance; for example Figure 5 As shown, the detection circuit is connected, the power supply 14, ammeter 16 and the metal wire 11 to be detected are connected in series, and the voltmeter 15 is connected in parallel at both ends of the metal wire 11 to be detected to measure the voltage, according to the voltage value and current value measured by the voltmeter 15 and ammeter 16, the resistance value of the metal wire 11 to be detected can be calculated. The difference is that in the embodiment, the resistivity detection device further includes a fixed frame 1 for clamping the metal wire 11 to be detected and a movable frame 2, the fixed frame 1 is fixed, and the movable frame 2 can move linearly along a guide rod 3 with scales, the scales mark the length of the corresponding position of the guide rod 3, to indicate the position and distance of the movable frame 2, when the movable frame 2 clamps one end of the metal wire away from the fixed frame 1 and moves linearly, the metal wire is straightened, at this time, the length of the metal wire when straightened can be directly read out by using the scales on the guide rod 3, so that the length of the metal wire does not need to be measured additionally. At the same time, the detection circuit mentioned above can measure the current and voltage at both ends of the metal wire, so that the resistance of the metal wire can be calculated, i.e. the principle of the common voltammetry method for measuring resistance, so as to substitute the resistance value to calculate the resistivity, the specific calculation method has been introduced in the background art, and itself is known to those skilled in the art, which will not be described here.

[0028] Specifically, as Figures 2-3As shown, the fixed frame 1 and the movable frame 2 are both provided with a clamping component 4, which comprises a circular main body 401 and a planar threaded disc 402 coaxially installed in the main body 401, and a tapered gear ring coaxially fixed at one end of the planar threaded disc 402, which is engaged with an adjusting bevel gear 403 rotatably installed in the sidewall of the planar threaded disc 402, so that when the adjusting bevel gear 403 is rotated, the planar threaded disc 402 will rotate to synchronously move all the slide columns 404 arranged in an annular array at the other end of the planar threaded disc 402, i.e. each slide column 404 is connected with the planar threaded disc 402 through a planar threaded pair transmission, and the ends of all the slide columns 404 approaching to each other are used to press the end of the metal wire to clamp the end of the metal wire, so as to fix the end of the metal wire.

[0029] More specifically, the ends of the slide columns 404 approaching to each other are fixed with arc-shaped pressing plates 405, which can be made thicker, so that the main body 401 can be made large enough, and the pressing plates 405 are used to press the end sidewall of the metal wire from the radial direction of the metal wire to better fix the end of the metal wire, and at the same time, straighten the end of the metal wire to ensure the flatness of the metal wire.

[0030] In the above embodiment, as Figure 1 The guide rod 3 is horizontally fixed on a pair of left and right support frames, and a rotatable lead screw 6 is also installed on the support frame 5 in parallel with the guide rod 3, the movable frame 2 is threadedly connected with the lead screw 6, the guide rod 3 axially slidably penetrates the movable frame 2 to guide the linear movement of the movable frame 2. A vertical limiting baffle 7 is fixed on one side of the movable frame 2 and the fixed frame 1, which is used to abut the end face of the metal wire to limit the installation position of the end of the metal wire, so as to ensure the accuracy of the length measurement of the metal wire. In practice, the limiting baffle 7 can be tightly attached to the end of the annular clamping structure formed by the pressing plates 405, or can be left with a certain distance, and the scale value can be adjusted accordingly when marking the scale on the guide rod 3. In order to facilitate indication, a indicating needle 10 is connected to the bottom end of the limiting baffle 7 on the movable frame 2, which is used to point to the corresponding scale on the guide rod 3 when the movable frame 2 moves horizontally.

[0031] In order to avoid excessive stretching of the metal wire after being straightened, or being pulled off, as a special structure, one end of the lead screw 6 is drivingly connected with the main shaft 12 of the motor 9 through an overload component 8, which makes the main shaft 12 relatively slip with the lead screw 6 to be disconnected when the torque on the lead screw 6 is greater than the set torque, so as to realize the over-pulling protection. As one of the specific implementation structures, as Figure 4The overload component 8 includes a socket cover 801 fixed to the end of the lead screw 6 and a plug boss 802 fixed to the end of the spindle 12. The plug boss 802 is axially inserted into the socket cover 801 and has the fitting accuracy to rotate within the socket cover 801. It is axially elastically pressed against the inner wall of the socket cover 801 by an elastic element 803. In use, when the wire is straightened, the movable frame 2 cannot move forward further, causing the plug boss 802 and the socket cover 801 to slip relative to each other against the elastic force, thus disengaging the lead screw 6 from the transmission and preventing accidental wire breakage. To improve the flexibility of the fit, a sliding disc 804 is connected to the end of the elastic element 803. The sliding disc 804 is in pressing contact with the inner wall of the socket cover 801, thus facilitating relative rotation during overload slippage.

[0032] Furthermore, in this embodiment, as Figure 4 The structure shown also includes a locking cover 806 rotatably fitted onto the main shaft 12. The locking cover 806 is threaded onto the outer wall of the socket cover 801, and several top pins 805 push the insertion boss 802 against the elastic element 803. Tightening the locking cover 806 adjusts the tightening force on the end face of the insertion boss 802, which can change the overload limit torque of the overload component 8 to accommodate metal wires of different materials. During installation, the top pins 805 are arranged parallel to the main shaft 12 and in a circular array around the main shaft 12, uniformly compressing the insertion boss 802. To maintain a certain stability of the locking cover 806, this embodiment also specifically installs a disc spring 13 between the end face of the locking cover 806 and the socket cover 801. The disc spring 13 is always in an axially compressed state, so that the locking cover 806 is always in a tendency to be pushed open to achieve pre-tightening.

[0033] Finally, another important design feature is that, in all the above embodiments, the corresponding clamping component 4, such as... Figure 3 and Figure 6As shown, outside the end of at least one slide column 404, an opposite infrared distance measuring element 406 is installed, which can be installed on the side of the main body 401, with a distance m from the end of the slide column 404, which indirectly represents the diameter of the metal wire 11 to be measured at the moment. A metal wire or other cylindrical rod that has been accurately measured is clamped on the clamping part 4 in advance, and the specific diameter of the specific metal wire or cylindrical rod is taken as the reference diameter d. The change in the distance between the above-mentioned infrared distance measuring element 406 and the slide column 404 is measured, and the reference diameter d is added or subtracted by 2 times the distance change, so as to obtain the diameter of the corresponding metal wire 11 to be measured. In this way, it is not necessary to use a screw micrometer every time the diameter of a metal wire is measured, which greatly saves detection time and is very ingenious. For example, when the specific metal wire is clamped, the distance between the above-mentioned infrared distance measuring element 406 and the slide column 404 is m1, which is taken as a constant reference calculation parameter of the present resistivity measuring instrument; in the experimental process, when the metal wire to be measured is clamped, the distance between the above-mentioned infrared distance measuring element 406 and the slide column 404 is m2, if m2 is greater than m1, it indicates that the diameter of the metal wire to be measured is smaller than the diameter of the specific metal wire taken as the reference, and the diameter value of the metal wire to be measured should be equal to d-2*(m2-m1). If m2 is less than m1, it indicates that the diameter of the metal wire to be measured is greater than the diameter of the specific metal wire taken as the reference, accordingly, the diameter value of the metal wire to be measured should be equal to d+2*(m1-m2). With the diameter value of the metal wire to be measured, the radius value of the metal wire to be measured can be obtained, and then the cross section of the metal wire to be measured can be calculated, so as to calculate the resistivity in combination with the length value of the metal wire and the resistance value of the metal wire connected to the detection circuit. The above calculation process can be adaptively programmed as an automatic operation program, which is more convenient to directly obtain the diameter value of the metal wire 11 to be measured.

[0034] As a preferred embodiment, since the resistivity is calculated by R=ρL / S, the resistivity of the above-mentioned specific metal wire can be calculated as ρ=πd 2 R / 3Lwherein d is the diameter of the metal wire, R is the resistance of the metal wire, and L is the length of the metal wire, so when the above-mentioned specific metal wire is taken as a reference in the calculation of the resistivity of the metal wire 11 to be measured, the ratio of the resistivity of the specific metal wire to the resistivity of the metal wire 11 to be measured is K=L x d 2 R / Ld x 2 R x , wherein L x is the length value of the metal wire to be measured, d x is the diameter value of the metal wire to be measured, and R xThe resistance value of the metal wire to be measured, and thus the resistivity of the metal wire 11, should be equal to Kp, and the value of the resistivity of the metal wire 11 is directly obtained. As a better embodiment, the length of the specific metal wire is set to be consistent with the length of the metal wire to be measured, and thus the resistivity of the metal wire 11 should be equal to Kp=pd 2 R / d x 2 R x =ρ(d / d x ) 2 R / R x , in the formula, the diameter value of the metal wire to be measured is d+2*(m1-m2), and thus the resistivity of the metal wire 11 is obtained.

[0035] The above only discloses a preferred embodiment of the utility model, and of course cannot limit the scope of the utility model, and those skilled in the art can understand that all or part of the processes of the above embodiment are realized, and equivalent changes made according to the utility model claims still belong to the scope covered by the utility model.

Claims

1. A metal wire resistivity measuring instrument, comprising a detection circuit for detecting the resistance of the metal wire, characterized in that, It also includes a fixed frame (1) and a movable frame (2) for clamping the metal wire (11) to be tested. The fixed frame (1) is fixed and the movable frame (2) can move linearly along a guide rod (3) with a scale. When the movable frame (2) clamps one end of the metal wire and moves linearly away from the fixed frame (1), the metal wire is straightened and the length of the straightened metal wire can be directly read from the scale on the guide rod (3). The detection circuit is a voltmeter-ammeter method for measuring resistance, which connects the two ends of the metal wire to obtain the resistance of the metal wire.

2. The metal wire resistivity measuring instrument according to claim 1, characterized in that, Both the fixed frame (1) and the movable frame (2) are equipped with clamping components (4). The clamping components (4) include a circular main body (401) and a planar threaded disk (402) coaxially rotatably installed in the main body (401). A conical toothed ring is coaxially fixed at one end of the planar threaded disk (402), and the conical toothed ring meshes with an adjusting bevel gear (403) rotatably installed in the side wall of the planar threaded disk (402). Several sliding columns (404) are arranged in a ring at the other end of the planar threaded disk (402). Each sliding column (404) is connected to the planar threaded disk (402) through a planar threaded pair. The ends of all the sliding columns (404) that are close to each other are used to squeeze the end of the metal wire to clamp the end of the metal wire.

3. The metal wire resistivity measuring instrument according to claim 2, characterized in that, An arc-shaped pressure plate (405) is fixed to one end of each of the sliding pins (404) that are close to each other. The pressure plate (405) is used to press the metal wire radially against the end sidewall of the metal wire. An infrared ranging element (406) is installed opposite to the end of at least one of the sliding pins (404).

4. The metal wire resistivity measuring instrument according to claim 1, characterized in that, The guide rod (3) is horizontally fixed on a pair of left and right arranged support frames, and a rotatable lead screw (6) is also installed on the support frame (5) parallel to the guide rod (3). The movable frame (2) is threadedly engaged with the lead screw (6), and the guide rod (3) slides through the movable frame (2) axially.

5. The metal wire resistivity measuring instrument according to claim 4, characterized in that, Vertically arranged limiting baffles (7) are fixed on one side of both the movable frame (2) and the fixed frame (1). The limiting baffles (7) are used to fit against the end face of the metal wire. An indicator needle (10) is connected to the bottom end of the limiting baffles (7) on the movable frame (2). The indicator needle (10) is used to point to the corresponding scale on the guide rod (3) when the movable frame (2) moves horizontally.

6. The metal wire resistivity measuring instrument according to claim 4, characterized in that, One end of the lead screw (6) is connected to the main shaft (12) of the motor (9) via an overload component (8). The overload component (8) causes the main shaft (12) and the lead screw (6) to slip relative to each other and disengage from the transmission connection when the lead screw (6) is subjected to a torque exceeding a set torque.

7. The metal wire resistivity measuring instrument according to claim 6, characterized in that, The overload component (8) includes a socket cover (801) fixed to the end of the lead screw (6) and a plug boss (802) fixed to the end of the main shaft (12). The plug boss (802) is axially inserted into the socket cover (801) and is axially elastically connected to the inner wall of the socket cover (801) by an elastic element (803). When the wire is straightened, the movable frame (2) cannot continue to move forward, causing the plug boss (802) and the socket cover (801) to slip relative to each other due to the elastic force.

8. The metal wire resistivity measuring instrument according to claim 7, characterized in that, The end of the elastic element (803) is connected to a sliding disk (804), and the sliding disk (804) is in pressure contact with the inner wall of the socket cover (801). It also includes a locking cover (806) that is rotatably fitted onto the main shaft (12), the locking cover (806) being threaded onto the outer side wall of the socket cover (801), and the insertion boss (802) being pushed against the elastic element (803) by a number of top pins (805).

9. The metal wire resistivity measuring instrument according to claim 8, characterized in that, The top pin (805) is arranged parallel to the main shaft (12) and arranged in a ring array around the main shaft (12).

10. The metal wire resistivity measuring instrument according to claim 8, characterized in that, A disc spring (13) is also installed between the end faces of the locking cover (806) and the socket cover (801), and the disc spring (13) is always in a state of axial compression.

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