CN205808677U - A kind of measuring device of spring stiffness coefficient - Google Patents

Abstract

The utility model discloses a spring stiffness coefficient measuring instrument, which comprises a spring force measuring device, a scale, a first fixed pulley, a first funnel, a second fixed pulley, a second funnel, a salt tank and a spring to be tested. One end of the dynamometer is fixed, the other end of the spring dynamometer is connected to the second funnel through the second fixed pulley, one end of the spring to be measured is fixed to one end of the scale, and the other end of the spring to be measured is passed through the first fixed pulley and The first funnel is connected, the first funnel is located directly above the second funnel, and the salt tank is located directly below the second funnel. The utility model controls the elongation of the spring by observing the change of the experimental content in the funnel. In the teaching process, this device can be directly used to verify the formula of the spring stiffness coefficient after the springs are connected in series and parallel. The experimental method of the utility model can be used in teaching. It makes it easy for students to grasp the principles of knowledge, which is beneficial for students to master scientific knowledge and has the value of popularization and application.

Description

A Measuring Instrument for Spring Stiffness Coefficient

technical field

The utility model relates to a physical experiment method, in particular to a spring stiffness coefficient measuring instrument.

Background technique

Stiffness coefficient, that is, the stubborn coefficient (elastic coefficient). It describes the size of the elastic force produced by unit deformation. If the k value is large, it means that the force required to deform the unit length is large, or the spring is "tough". Stiffness coefficient is also called stiffness coefficient or stubbornness coefficient. The stiffness coefficient is numerically equal to the elastic force when the spring is stretched (or shortened) per unit length. In the prior art, it is cumbersome to test the stiffness coefficient of the spring, the work is cumbersome, the efficiency is low, and the accuracy is not enough. Therefore, there is room for improvement.

Utility model content

The purpose of this utility model is to provide a spring stiffness coefficient measuring instrument in order to solve the above problems.

The utility model realizes above-mentioned purpose through following technical scheme:

The utility model relates to a spring stiffness coefficient measuring instrument, which comprises a spring force measuring device, a scale, a first fixed pulley, a first funnel, a second fixed pulley, a second funnel, a salt tank and a spring to be tested. One end of the dynamometer is fixed, the other end of the spring dynamometer is connected between the second fixed pulley and the second funnel, one end of the measured spring is fixed on one end of the scale, the The other end of the spring to be tested is connected to the first funnel through the first fixed pulley, the first funnel is located directly above the second funnel, and the salt tank is located directly below the second funnel, Both the first funnel and the second funnel are provided with switches.

The beneficial effects of the utility model are:

The utility model is a spring stiffness coefficient measuring instrument. Compared with the prior art, the utility model controls the elongation of the spring by observing the change of the experimental content in the funnel. This process uses reverse thinking and can be fully grasped by students. This concept cleverly uses the idea of "transformation" to change the reduction amount into an increase amount, and directly uses the spring dynamometer to measure the output force. In the teaching process, this device can be directly used to verify the formula of the spring stiffness coefficient after the springs are connected in series and parallel. The experimental method of the utility model can enable students to easily grasp knowledge principles in teaching, is beneficial for students to grasp scientific knowledge, and has the value of popularization and application.

Description of drawings

Fig. 1 is a structural representation of the utility model.

In the figure: 1-spring dynamometer, 2-scale, 3-the first fixed pulley, 4-the first funnel, 5-the second fixed pulley, 6-the second funnel, 7-salt tank, 8-the measured spring.

detailed description

Below in conjunction with accompanying drawing, the utility model is further described:

As shown in Figure 1: a spring stiffness coefficient measuring instrument of the utility model includes a spring dynamometer 1, a scale 2, a first fixed pulley 3, a first funnel 4, a second fixed pulley 5, and a second funnel 6 , salt tank 7 and measured spring 8, one end of the spring dynamometer 1 is fixed, and the other end of the spring dynamometer 1 is connected between the second fixed pulley 5 and the second funnel 6, One end of the measured spring 8 is fixed on one end of the scale 2, and the other end of the measured spring 8 is connected with the first funnel 4 through the first fixed pulley 3, and the first funnel 4 Located directly above the second funnel 6 , the salt tank 7 is located directly below the second funnel 6 , and both the first funnel 4 and the second funnel 6 are provided with switches.

The testing method of the spring stiffness coefficient measuring instrument of the present utility model comprises the following steps:

(1) After the spring to be tested is fixed, the spring dynamometer 1 is adjusted to zero, and the first funnel 4 and the second funnel 6 are closed simultaneously;

(2) any amount of salt is put into the first funnel 4, and the scale 2 reading corresponding to the elongation of the measured spring 8 is recorded;

(3) Open the first funnel 4, make part of the salt flow in the second funnel 6, close the first funnel 4, record the scale value X2 of the measured spring 8 and the numerical value F1 of the spring dynamometer 1 simultaneously; Open the second funnel 6 , so that all the salt in the second funnel 6 flows out and then close the second funnel 6;

(4) Calculate △X1=X2-X1 from "X1, X2", K1=F1/△X1;

(5) Repeat the above steps to get K2=F2/△X2, K3=F3/△X3;

(6) The stiffness coefficient of the measured spring 8 is: KA=(K1+K+K3)=(F1/△X1+F2/△X2+F3/△X3)/3;

(7) Change the spring under test into another spring under test 8, repeat the step of measuring the stiffness coefficient, and obtain the stiffness coefficient KB=(K1+K2+K3)/3=(F1 /△X1+F2/△X2+F3/△X3)/3;

(8) two measured springs 8 are connected in series, repeat above steps, obtain the equivalent spring stiffness coefficient K string of two measured springs 8;

(9) Verify the equivalent stiffness coefficient formula 1/K string=1/KA+1/KB after the springs are connected in series;

(10) two measured springs 8 are connected in parallel, repeat the above steps, obtain the stiffness coefficient K of the total spring after the parallel connection of the two measured springs 8 and;

(11) Verify the equivalent stiffness coefficient formula K and = KA + KB after the springs are connected in parallel.

data measurement

The stiffness coefficient K _{A of spring A}

Table 1 The stiffness coefficient K _{A of spring A}

K _A ＝(K ₁ +K ₂ +K ₃ )/3＝(F ₁ /△X ₁ +F ₂ /△X ₂ +F ₃ /△X ₃ )/3＝0.377N/cm

The stiffness coefficient K _{B of spring B}

Table 2 The stiffness coefficient K _{B of spring B}

K _B ＝(K ₁ +K ₂ +K ₃ )/3＝(F ₁ /△X ₁ +F ₂ /△X ₂ +F ₃ /△X ₃ )/3＝0.231N/cm

Stiffness coefficient K _series after series connection

Table 3 Stiffness coefficient K _series after series connection

K _string =(K ₁ +K ₂ +K ₃ )/3=(F ₁ /△X ₁ +F ₂ /△X ₂ +F ₃ /△X ₃ )/3＝0.143N/cm

And according to the formula 1/K _{string (theory)} = 1/K _A +1/K _B get K _{string (theory)} = 0.141N/cm

K _{string (theory)} ≈ K _string

So this formula is correct within the range of experimental error.

The stiffness coefficient K after _parallel connection

Table 4 Stiffness coefficient K after _parallel connection

K _and = (K ₁ +K ₂ +K ₃ )/3=(F ₁ /△X ₁ +F ₂ /△X ₂ +F ₃ /△X ₃ )/3＝0.604N/cm

And according to the formula K _{and (theory)} = K _A + K _B get K _{and (theory)} = 0.608N/cm

K union _(theory) ≈K _union

So this formula is correct within the range of experimental error.

The basic principles and main features of the present utility model and the advantages of the present utility model have been shown and described above. Those skilled in the art should understand that the utility model is not limited by the above-mentioned embodiments. The above-mentioned embodiments and descriptions only illustrate the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model The new model also has various changes and improvements, and these changes and improvements all fall within the scope of the claimed utility model. The scope of protection required by the utility model is defined by the appended claims and their equivalents.

Claims (1)

1. a spring stiffness coefficient measuring instrument, is characterized in that: comprise spring dynamometer, scale, the first fixed pulley, the first funnel, the second fixed pulley, the second funnel, salt tank and measured spring, so One end of the spring dynamometer is fixed, the other end of the spring dynamometer is connected between the second fixed pulley and the second funnel, and one end of the measured spring is fixed to one end of the scale , the other end of the spring under test is connected to the first funnel through the first fixed pulley, the first funnel is located directly above the second funnel, and the salt tank is located at the top of the second funnel Directly below, switches are provided on the first funnel and the second funnel.