CN206179340U

CN206179340U - Three string pendulums with pivot angle indicating device

Info

Publication number: CN206179340U
Application number: CN201621134034.0U
Authority: CN
Inventors: 陈健; 周锡生; 朱纯
Original assignee: Jiangnan University
Current assignee: Jiangnan University
Priority date: 2016-10-18
Filing date: 2016-10-18
Publication date: 2017-05-17
Anticipated expiration: 2026-10-18

Abstract

The utility model discloses a three string pendulums with pivot angle indicating device, including support, three string pendulums, photoelectricity door, time -recorder, still include micro laser ware and angle scale, the micro laser ware is fixed at the lower surface center of disc down, the position of equal height is fixed in the pole setting of support with the micro laser ware to the angle scale, micro laser ware along horizontal direction lasing line directive angle scale, micro laser ware swing along with disc down and indicate by the position change of laser ray on the angle scale under the pivot angle of disc. The utility model discloses simple structure, practical convenient, pivot angle that can three string pendulums of visual indication is favorable to experimenter control pivot angle size, the inertia of accurate determination of rigid body.

Description

A kind of three-line pendulum with pivot angle instruction device

Technical field

This utility model is related to a kind of measuring moment of inertia instrument, specially a kind of three-line pendulum with pivot angle instruction device.

Background technology

Three-line pendulum is the conventional Experiments of Machanics instrument of Measuring Object rotary inertia, typically by upper disk, lower disc and connection Three suspension wires composition of disk and lower disc is tied, wherein lower disc is used for placing object under test, before placement object under test Afterwards the change of three-line pendulum rotation period is measuring the rotary inertia of object under test.During experiment, it is desirable to which three-line pendulum lower disc does little angle Degree swings, and pivot angle is less than 5⁰.But, existing three-line pendulum is all indicated and control device without pivot angle, in causing experimentation The size of lower disc pivot angle cannot be accurately controlled, many students pivot angle in experiment can all be more than 5⁰, thus increase experimental error.

The content of the invention

The purpose of this utility model is to overcome the shortcomings of existing three-line pendulum, exploitation a kind of with pivot angle instruction device three String pendulum.

In order to solve above-mentioned technical problem, this utility model is employed the following technical solutions：

A kind of three-line pendulum with pivot angle instruction device, including support, three-line pendulum, photogate, timer, the three-line pendulum It is made up of the suspension wire of upper disk, lower disc and three equal lengths for being coupled upper disk and lower disc, upper disc centre is arranged One rotating shaft, rotating shaft is vertically fixed on the crossbeam of support, and lower disc edge level is fixed one and is in the light bar, and photogate is fixed on support Vertical rod on the contour position of bar and guarantee to be in the light the inswept photogate of bar, photogate and timer phase when lower disc is rotated with being in the light It is used in conjunction the hunting period of measurement lower disc；It is characterized in that：Also include microlaser and angle scale, microlaser is solid The lower surface center of lower disc is scheduled on, angle scale is fixed in the vertical rod of support the position contour with microlaser, miniature Laser instrument launches in the horizontal direction laser rays directive angle scale, and microlaser swings and by angle scale with lower disc The change in location of upper laser rays indicates the pivot angle of lower disc.

The beneficial effects of the utility model are：By microlaser and angle scale, the pendulum of three-line pendulum can be intuitively observed Dynamic angle, is conducive to control three-line pendulum to do small angle oscillation, improves the accuracy of experiment measurement.This utility model simple structure, It is practical and convenient, the pivot angle of three-line pendulum can be intuitively indicated, be conducive to experimenter to control pivot angle size, the rotation of Accurate Determining rigid body is used to Amount.

Description of the drawings

Below in conjunction with the accompanying drawings the utility model is described in further detail.

Fig. 1 is composition schematic diagram of the present utility model.

Fig. 2 is angle scale scale design schematic diagram.

In figure：1. three-line pendulum, 2. support, 3. photogate, 4. timer, 5. microlaser, 6. angle scale, on 11. Disk, 12. lower discs, 13. suspension wires, 14. are in the light bar.

Specific embodiment

As shown in figure 1, three-line pendulum 1 by upper disk 11, lower disc 12 and be coupled upper disk 11, three of lower disc 12 it is long The equal suspension wire 13 of degree is constituted, and the centrally disposed rotating shaft of upper disk 11, rotating shaft is vertically fixed on the crossbeam of support 2, lower disc 12 edge levels are fixed one and are in the light bar 14, and it is contour and guarantee that photogate 3 is fixed in a vertical rod of support 2 and is in the light bar 14 Be in the light the inswept photogate 3 of bar 14 during the rotation of lower disc 12, and photogate 3 is connected for the swing for measuring lower disc 12 with timer 4 Cycle.Microlaser 5 is fixed on the lower surface center of lower disc 12, and angle scale 6 is fixed in another vertical rod of support 2 And it is contour with microlaser 5, microlaser 5 launches in the horizontal direction laser rays directive angle scale 6, microlaser 5 Swing with lower disc 12, the pivot angle of lower disc 12 is indicated by the change in location of laser rays on angle scale 6.

As shown in Fig. 2 when lower disc 12 does not swing, laser rays just penetrate the zero degree groove at the middle part of angle scale 6 in fig. 2 On A.When the pivot angle of lower disc 12 is θ, laser rays are penetrated at the B of angle scale 6.The center of disk 12 is set to angle scale 6 Vertical dimension be L, the distance of B to A is x, can be obtained by geometrical relationship in figure：X=Ltan θ, by the formula angle can be demarcated Dial markings on scale 6.

Because the pivot angle of lower disc 12 in experiment is less than 5⁰, by x=Ltan5⁰The value of x can be obtained, in angle scale 6 Mark the groove of B, C two at upper zero degree groove A or so x distances respectively.During experiment, three-line pendulum is allowed to swing, when laser rays or so When scanning is less than two groove of B, C, that is, pivot angle is met less than 5⁰Condition, now just can carry out the measurement of hunting period.

Claims

1. a kind of three-line pendulum with pivot angle instruction device, including support, three-line pendulum, photogate, timer, the three-line pendulum by The suspension wire of upper disk, lower disc and three equal lengths for being coupled upper disk and lower disc is constituted, and upper disc centre arranges one Rotating shaft, rotating shaft is vertically fixed on the crossbeam of support, and lower disc edge level is fixed one and is in the light bar, and photogate is fixed on support With the contour position of bar of being in the light in vertical rod, photogate was connected for the hunting period for measuring lower disc with timer；Its feature exists In：Also include microlaser and angle scale, microlaser is fixed on the lower surface center of lower disc, and angle scale is fixed The position contour with microlaser in the vertical rod of support, microlaser launches in the horizontal direction laser rays directive angle mark Chi, microlaser swings with lower disc and indicates the pivot angle of lower disc by the change in location of laser rays on angle scale.