CN221426309U - Young modulus measuring instrument - Google Patents

Abstract

The utility model discloses a Young modulus measuring instrument, relates to the technical field of Young modulus measuring instruments, and solves the problems of inconvenient adjustment and inaccurate measurement of the Young modulus measuring instrument in the prior art. The base is provided with a stand column, the stand column is vertically and adjustably provided with a supporting sliding table, the supporting sliding table is provided with a strain gauge, the stand column is vertically and adjustably provided with a clamping frame, the clamping frame is provided with a spiral micrometer, the spiral micrometer is matched with the strain gauge, and the strain gauge is connected with a strain gauge bridge circuit. The micro displacement amplifier used for displaying and amplifying the length change of the metal wire in the prior art is replaced by the strain gauge, so that the length change of the metal wire is measured by the strain gauge, and the measurement result is more accurate. The adjustable setting support slip table on the stand to be convenient for adjust the initial position of foil gage after carrying out different wire installation, with confirm measuring initial position, it is convenient to measure for prior art, and measuring result is more accurate.

Description

A Young's modulus measuring instrument

Technical Field

The utility model relates to the technical field of Young's modulus measuring instruments, in particular to a Young's modulus measuring instrument.

Background technique

When a material is subjected to force, it deforms. Within the elastic limit, the ratio of the stress strength to the stress deformation (i.e., relative deformation) of the material is a constant, called the elastic modulus. The elastic modulus of a bar-shaped object (such as a steel wire) along the longitudinal direction is called the Young's modulus. The Young's modulus is an important physical quantity that characterizes the properties of a solid, especially in engineering technology. It is often used to describe the ability of solid materials to resist deformation, and can also be used as a basis for selecting mechanical components. The measurement of the Young's modulus includes the stretching method, the beam bending method, the vibration method, the internal friction method, and so on. In university physics experiments, the stretching method is often used to measure the Young's modulus of a metal wire. This method measures the elongation Δl of the metal wire under different forces by conducting a stretching test on the metal wire, thereby calculating the Young's modulus. Because the elongation Δl is generally very small, the optical lever method is often used to measure a small amount, that is, it is magnified by optical magnification, and then the plane mirror is rotated to magnify the small angular displacement into a larger linear displacement for measurement. The traditional optical lever method for measuring Young's modulus requires measuring the distance from the optical lever plane mirror to the scale. The larger distance will lead to inconvenience in experimental operation. In addition, the optical lever is difficult to operate and is easily affected by the external environment, resulting in large experimental errors and a long time.

The Chinese invention patent with the publication number CN113533033A discloses a metal wire Young's modulus measuring instrument based on the principle of hydraulic micro-displacement amplifier, which mainly includes weights, weight discs, syringes, infusion tubes, capillaries and scales. The metal wire to be measured for Young's modulus is set vertically, the upper end of the metal wire is fastened to the iron frame, and the lower end passes through the center hole of the fixing part and is connected to the upper surface of the weight disc; the syringe, capillary and infusion tube are connected to form a micro-displacement amplifier; the capillary is set vertically, and the capillary is made of hydrophobic material; the scale is used to display the position of the liquid level inside the capillary. By adding and subtracting weights on the weight disc, the up and down movement of the weight disc is reflected in the displacement of the syringe piston. The displacement of the syringe piston causes the change of pressure in the syringe, which causes the water level in the capillary to change. The invention has a larger magnification, more accurate observation, easier operation, simple experimental instruments, and intuitive experimental phenomena.

However, before measuring, after the metal wire to be measured is installed, due to different installation accuracy and position, the position of the syringe and the zero point position of the scale corresponding to the initial liquid level need to be recalibrated, but its structure lacks a flexible adjustment structure, so there is a problem of inconvenient adjustment. In addition, since there is friction between the piston and the syringe and the friction force is large, it is easy to cause inaccurate measurement due to the existence of friction when the weight presses down the piston end.

Utility Model Content

In view of the deficiencies in the above-mentioned background technology, the utility model proposes a Young's modulus measuring instrument, which solves the problems of inconvenient adjustment and inaccurate measurement of the Young's modulus measuring instrument in the prior art.

The technical solution of the utility model is implemented as follows: a Young's modulus measuring instrument, wherein a column is provided on the base, a support slide is provided on the column in a vertically adjustable manner, a strain gauge is provided on the support slide, a clamping frame is provided on the column in a vertically adjustable manner, a micrometer is provided on the clamping frame, the micrometer is coordinated with the strain gauge, and the strain gauge is connected to a strain gauge bridge circuit.

Preferably, the base comprises a counterweight chassis, and an adjustable foot is arranged below the counterweight chassis. Further, the adjustable foot comprises a screw threadedly connected to the counterweight chassis, the lower end of the screw is connected to the rubber pad, and a locking nut is arranged on the screw.

Preferably, the columns are vertically fixed on the counterweight chassis and at least two columns are provided. The support slide comprises a joist, on which a clamping ear seat I is provided and connected to a sliding bearing I slidably provided on the column through the clamping ear seat I; the clamping ear seat I is provided with a first locking member that cooperates with the side wall of the column; the joist is provided with a support frame, and a strain gauge is provided on the support frame.

Preferably, the support frame is provided with a second locking member that cooperates with the strain gauge. The clamping frame is provided with a U-shaped card at one end and a clamping ear seat II at the other end. The clamping ear seat II is connected to a sliding bearing II that is slidably arranged on the column. The micrometer screw is arranged at the opening of the U-shaped card and the U-shaped card is provided with a third locking member that cooperates with the micrometer screw. The clamping ear seat II is provided with a fourth locking member that cooperates with the column. Further, the first locking member, the second locking member, the third locking member, and the fourth locking member are all set screws.

Preferably, a top fixing seat is provided on the top of the column, the top fixing seat is connected to a metal wire, the metal wire is connected to a cylindrical connecting rod, the cylindrical connecting rod is connected to a weight support, and a stabilizing platform matching the cylindrical connecting rod is provided on the column.

Preferably, the stabilizing platform includes a cross arm, which is provided with a through hole for a cylindrical connecting rod to pass through, a column passing through an end of the cross arm, and a fastening knob that cooperates with the column is threadedly connected to the cross arm.

The beneficial effects of the utility model are as follows: by replacing the micro-displacement amplifier used in the prior art for displaying and amplifying the change in length of the metal wire with a strain gauge, using a strain gauge bridge circuit connected to the strain gauge to measure the obvious change in electrical parameters caused by a micro-change in the length of the metal wire, and using electrical parameters to replace displacement for measurement, the measurement result is more accurate. By setting an adjustable support slide on the column, it is convenient to adjust the initial position of the strain gauge after installing different metal wires to determine the initial position of the strain gauge during measurement; by using a clamping frame to set a screw micrometer on the column, the corresponding relationship coefficient between the displacement change of the contact of the strain gauge and the measurement indication of the strain gauge bridge circuit can be calibrated before measurement, so as to facilitate the subsequent calculation of the actual displacement of the metal wire through the measurement indication and coefficient of the strain gauge bridge circuit when adding or subtracting weights, and the measurement is accurate and reliable.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic diagram of the three-dimensional structure of the utility model;

Figure 2 is an enlarged schematic diagram of the lower structure of the utility model;

FIG3 is a schematic structural diagram of the lower part of the utility model from another perspective;

FIG. 4 is an enlarged schematic diagram of the upper structure of the utility model.

Detailed ways

The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

As shown in Figures 1, 2, and 4, in Embodiment 1, a Young's modulus measuring instrument is provided, wherein a column 2 is provided on a base 1, and a support slide 3 is provided on the column 2 in a vertically adjustable manner, and a strain gauge 4 is provided on the support slide 3. The support slide 3 is provided in this embodiment to facilitate adjustment of the initial position of the strain gauge after installation of different metal wires, so as to determine the initial position of the strain gauge during measurement. A clamping frame 5 is provided on the column 2 in a vertically adjustable manner, and a micrometer screw 6 is provided on the clamping frame 5. The micrometer screw 6 is provided in conjunction with the strain gauge 4, and the strain gauge 4 is connected to the strain gauge bridge circuit. In this embodiment, by replacing the micro-displacement amplifier used in the prior art for displaying and amplifying the change in the length of the metal wire with a strain gauge, a strain gauge bridge circuit connected to the strain gauge is used to measure the significant change in the electrical parameter caused by the micro-change in the length of the metal wire, and the displacement is replaced by the electrical parameter for measurement, the measurement result is more accurate. By making it adjustable on the column. By using a clamping frame to set a micrometer on the column, the corresponding coefficient between the displacement change of the strain gauge contact and the measurement indication of the strain gauge bridge circuit can be calibrated before measurement, so as to facilitate the subsequent calculation of the actual displacement of the metal wire through the measurement indication and coefficient of the strain gauge bridge circuit when adding or subtracting weights, and the measurement is accurate and reliable.

In addition, in this embodiment, as a further specific implementation, a top fixing seat 21 is provided at the top of the column 2, and the top fixing seat 21 is connected to the metal wire 22 to be measured, and the metal wire 22 is connected to the cylindrical connecting rod 23, and the cylindrical connecting rod 23 is connected to the weight support 24. A stabilizing platform matched with the cylindrical connecting rod 23 is provided on the column 2. Among them, the stabilizing platform includes a cross arm 26, and a through hole is provided on the cross arm 26 to meet the passing of the cylindrical connecting rod 23. The diameter of the through hole is slightly larger than the diameter of the cylindrical connecting rod. After leveling, there is no contact and friction between the cylindrical connecting rod and the through hole without adding weights, and the measuring frame is vertical at this time. The column 2 passes through the end of the cross arm 26 and the cross arm 26 is threadedly connected with a tightening knob 27 that cooperates with the column 2. When the tightening knob is tightened, the end is pressed against the column, thereby locking the position of the cross arm. In addition, in this embodiment, the upper end of the cylindrical connecting rod is fixed to the metal wire by bolt compression, and the lower end of the cylindrical metal rod is threadedly connected to the weight support. The optional cylindrical connecting rod has a clamp on top that can clamp the wire to secure it.

Embodiment 2, a Young's modulus measuring instrument, based on Embodiment 1, the base 1 includes a counterweight frame 7, and an adjustable foot is arranged below the counterweight frame 7. Specifically, in this embodiment, the counterweight frame is an A-shaped triangular frame, and three adjustable feet are arranged on the counterweight frame to form a support. The adjustable foot includes a screw 8 threadedly connected to the counterweight frame 7, the lower end of the screw 8 is connected to the rubber pad 9, and the screw 8 is provided with a locking nut. The column 2 is vertically fixed on the counterweight frame 7 and at least two are arranged. In this embodiment, two columns are arranged, both of which are arranged vertically with the counterweight frame and are fixed by welding or bolts.

In addition, as an optional embodiment, a level is provided on the counterweight chassis, which can be used as a reference when leveling the counterweight chassis or the entire measuring instrument.

When leveling the counterweight chassis, rotate the screws of different adjustable feet to change the distance from the rubber pad to the counterweight chassis, thereby achieving the purpose of adjusting the height and levelness, and finally use the locking nut to lock the screw position.

Embodiment 3, as shown in FIG3, is a Young's modulus measuring instrument. Based on Embodiment 2, the support slide 3 includes a support beam 11, and both ends of the support beam 11 are provided with clamping ear seats Ⅰ12 and connected to a sliding bearing Ⅰ13 slidably provided on the column 2 through the clamping ear seats Ⅰ12. In this embodiment, a first locking member 14 that cooperates with the side wall of the column 2 is provided on the clamping ear seat Ⅰ12. When the height position of the strain gauge needs to be adjusted, the first locking member is rotated to separate its end from the column, and the entire support slide is moved along the column to realize the movement of the strain gauge, and finally the first locking member is tightened to form a lock.

In addition, a support frame 15 is provided on the supporting beam 11, and the strain gauge 4 is provided on the support frame 15. A second locking member 16 cooperating with the strain gauge 4 is provided on the support frame 15. In this embodiment, the support frame is arranged in a U shape, and a total of four second locking members are provided to clamp and fix the strain gauge from the two side walls respectively.

Embodiment 4, a Young's modulus measuring instrument, based on embodiment 3, a U-shaped card 17 is provided at one end of the clamping frame 5, and a clamping ear seat II 18 is provided at the other end, and the clamping ear seat II 18 is connected to the sliding bearing II slidably provided on the column 2. In this embodiment, the clamping frame can rotate and slide relative to the column under the action of the sliding bearing II. The micrometer 6 is arranged at the opening of the U-shaped card 17, and the U-shaped card 17 is provided with a third locking member 19 that cooperates with the micrometer 6, and the clamping ear seat II 18 is provided with a fourth locking member 20 that cooperates with the column 2. In this embodiment, two third locking members are provided on the U-shaped card, and the micrometer can be tightened and locked by the third locking member. The fourth locking member can lock the position of the clamping frame on the column. In this embodiment, the first locking member 14, the second locking member 16, the third locking member 19, and the fourth locking member 20 are all set screws.

The above embodiment is carried out by the following steps when in use:

S1. Connect the strain gauge bridge circuit: Connect the strain gauge to the strain gauge bridge circuit in the conventional way of connecting the strain gauge bridge circuit. To obtain the most obvious effect, it is preferred that the strain gauge bridge circuit adopts a full-bridge circuit for the experiment.

S2. Calibrate the coefficient of the correspondence between the displacement change of the contact of the strain gauge and the measurement indication of the strain gauge bridge circuit: 1. Rotate the fine adjustment knob of the micrometer screw to open a sufficient distance between the measuring rod and the measuring anvil of the micrometer screw. 2. Move the clamping frame 5 so that the screw of the micrometer screw is close to the contact of the strain gauge, and lock the position of the clamping frame 5 on the column. 3. Rotate the fine adjustment knob of the micrometer screw so that the measuring rod just touches the contact of the strain gauge. At this time, the voltage reading of the strain gauge bridge circuit changes from 0 to a value slightly greater than 0. 4. Then rotate the fine adjustment knob of the micrometer screw so that the measuring rod of the micrometer screw presses the contact of the strain gauge to bend and move downward. At this time, the voltage meter measurement value in the strain gauge bridge circuit increases. Record the reading and voltage value of the micrometer screw, and calculate the coefficient of the correspondence between the displacement and the voltage value. 5. After calibration, move the clamping frame to separate the micrometer screw from the strain gauge and remove it.

S3. System error correction: Place the weights on the contacts of the strain gauge 4 in sequence. When the strain gauge contacts are stable, the elastic force and the gravity of the weights are balanced. Record the voltage value when stable to obtain the relationship curve between voltage and elastic force.

S4. Adjustment of the working state of the Young's modulus of elasticity instrument. Install the metal wire to be measured between the top fixing seat and the cylindrical connecting rod, rotate the adjustable feet to level the entire measuring instrument to make the measuring instrument vertical. Then adjust the height of the supporting slide so that the lower side of the weight plate is placed in contact with the contact point of the strain gauge.

5. Measure the length l and diameter d of the wire, and calculate the cross-sectional area S of the wire.

6. Record the initial voltage reading of the strain gauge bridge circuit, then add the weight while recording the voltage value and calculating the Young's modulus.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. Young's modulus measuring instrument, including base (1), its characterized in that: be equipped with stand (2) on base (1), vertical adjustable on stand (2) is equipped with supports slip table (3), is equipped with foil gage (4) on supporting slip table (3), vertical adjustable on stand (2) is equipped with holder (5), be equipped with spiral micrometer (6) on holder (5), spiral micrometer (6) and foil gage (4) cooperation setting, foil gage (4) are connected with foil gage bridge circuit.

2. Young's modulus meter according to claim 1, characterized in that: the base (1) comprises a counterweight underframe (7), and adjustable supporting feet are arranged below the counterweight underframe (7).

3. Young's modulus meter according to claim 2, characterized in that: the adjustable support leg comprises a screw rod (8) in threaded connection with the counterweight underframe (7), the lower end of the screw rod (8) is connected with a rubber pad (9), and a locking nut is arranged on the screw rod (8).

4. Young's modulus meter according to claim 2, characterized in that: the upright posts (2) are vertically and fixedly arranged on the counterweight underframe (7) and at least two upright posts are arranged.

5. The young's modulus measuring instrument according to any one of claims 1 to 4, wherein: the supporting sliding table (3) comprises a joist (11), wherein a clamping lug seat I (12) is arranged on the joist (11) and is connected with a sliding bearing I (13) arranged on the upright post (2) in a sliding manner through the clamping lug seat I (12); a first locking piece (14) matched with the side wall of the upright post (2) is arranged on the holding ear seat I (12); the support frame (15) is arranged on the joist (11), and the strain gauge (4) is arranged on the support frame (15).

6. The young's modulus meter according to claim 5, wherein: the support frame (15) is provided with a second locking piece (16) matched with the strain gauge (4).

7. The young's modulus meter according to claim 6, wherein: the clamping frame (5) one end is equipped with U type card (17), and the other end is equipped with embraces and presss from both sides ear seat II (18), embraces and presss from both sides ear seat II (18) and slide and establish slide bearing II on stand (2) and be connected, spiral micrometer ware (6) set up in U type card (17) opening part and be equipped with on U type card (17) with spiral micrometer ware (6) complex third retaining member (19), embraces and is provided with on clamp ear seat II (18) with stand (2) complex fourth retaining member (20).

8. The young's modulus meter according to claim 7, wherein: the first locking piece (14), the second locking piece (16), the third locking piece (19) and the fourth locking piece (20) are all set screws.

9. The young's modulus measuring instrument according to any of claims 1-4, 6-8, wherein: the top of stand (2) is equipped with top fixing base (21), and top fixing base (21) are connected with wire (22), and wire (22) are connected with cylinder connecting rod (23), and cylinder connecting rod (23) are connected with weight support (24), are equipped with on stand (2) with cylinder connecting rod (23) matched with stable platform.

10. The young's modulus meter according to claim 9, wherein: the stabilizing table comprises a cross arm (26), a through hole which is used for allowing a cylindrical connecting rod (23) to pass through is formed in the cross arm (26), and a fastening knob (27) which is matched with the upright post (2) is connected to the end part of the cross arm (26) in a threaded manner.