CN2453498Y

CN2453498Y - Friction experiment demonstration instrument

Info

Publication number: CN2453498Y
Application number: CN 00252518
Authority: CN
Inventors: 吴庆柏
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-10-12
Filing date: 2000-10-12
Publication date: 2001-10-10
Anticipated expiration: 2010-10-12

Abstract

The utility model discloses a friction experiment demonstration instrument, mainly composed of a transparent spring balance, a frame, and a wood board. The pointer and the graduation of the transparent spring balance are comparatively obvious with convenient reading, and the frame is provided with rolling wheels, a conveying belt, and a handle. Wood slide blocks can be moved continuously on the conveying belt through turning the handle. The utility model has the advantages of convenient operation, accurate experiment, and visual demonstration, can fully reveal the relative factors to sliding friction force, and can accurately detect the values of rolling friction force and the sliding friction force.

Description

The frictional experiment demonstrator

The utility model relates to a kind of physical teaching aid, is specifically related to a kind of demonstrator of frictional experiment.

First mechanics part of junior physics has the size experiment relevant with which of a research force of sliding friction, in field research, find several problems, the one, plank length is too short in the experiment, when the experimenter spurs spring balance, when making wooden unit at the uniform velocity, wooden unit is near the terminal of plank; The 2nd, experiment principle has weak point, this principle is to utilize object under equilibrium condition, straight-line a kind of mobile equilibrium promptly remains a constant speed, also be that a kind of instability is steady, so and to keep this very difficult numerical value of accurately measuring force of sliding friction when this experiment of demonstration that dynamically steadily is not easy very much; The 3rd, the reading difficulty, when in experimentation, surveying friction force big or small, since firmly inhomogeneous, the pointer of spring balance is shaken at the volley, be difficult to read accurate numerical value.

The purpose of this utility model is to provide a kind of frictional experiment demonstrator, has the reading of being convenient to, maneuverable characteristics, and it is relevant with which factor fully to disclose force of sliding friction, and can accurately measure the size of force of sliding friction and the size of force of rolling friction.

For accompanying drawing is at first drawn in convenient narration;

Fig. 1 is the stereographic map of the utility model frictional experiment demonstrator.

As shown in the figure, the frictional experiment demonstrator is made up of transparent spring scale 4, movement frame 13 and platform 6, Transparent spring scale 4 and movement frame 13 are separately fixed on the table top, transparent spring scale by spring scale 1, with The transparent shell of scale, pulley 5, truckle 12 and cord 3 form, and spring scale one end is fixed on housing The top, the other end is installed pointer 2, and spring is connected with cord, and cord is walked around and is fixed on the housing lower right Pulley 5, hang on the truckle 12 that is fixed on housing sidewall; Movement frame by framework 7, diaxon roller 11, Conveyer belt 8 and handle 10 form, and the diaxon roller is installed on the framework, and conveyer belt 8 is enclosed within on the diaxon roller 11, Handle is installed in the termination of an axle roller; On conveyer belt, place a wooden slide block 12, by spring scale The cord traction. This handle can be manual, also can be driven by motor 9.

Demenstration method: 1, this teaching aid is placed on the horizontal table top, adjusts spring scale and keep vertically, Put wooden slide block well at driving-belt, the cord on the spring scale is hung on the wooden slide block. Use hand fixed handle Make conveyer belt, slide block is relative sliding on conveyer belt, observes the frictional force that spring scale is measured this moment.

2, change axle roller rotating speed, the registration of observing spring balance.Demonstration draws the size of force of sliding friction and the speed of travelling belt has nothing to do.

3, on wooden slide block, add two weights and four weights respectively.Shake handle, observe the position of spring balance pointer, reach a conclusion: the size of force of sliding friction is relevant with the size of pressure.Pressure is big more, and force of sliding friction is big more.

4, change the wooden slide block that white glues cloth is posted in the bottom surface, make conveyer belt, measure force of sliding friction.Put two weights and four weights more respectively, measure their force of sliding friction, relatively draw with the data of the 1st, 3 steps: under the certain condition of pressure, the size of force of sliding friction is relevant with the degree of roughness of surface of contact, and it is big more to contact coarse more friction force.

5, the dolly that wooden slide block is changed into belt wheel makes conveyer belt, measures the size of friction force.Can reach a conclusion: force of rolling friction is smaller.

Advantage of the present utility model is: 1, transparent spring balance has overcome former teaching and can only keep flat with spring balance, and scale is less, is difficult for defectives such as observation, can read experimental data more clearly, exactly; 2, original plank is changed into the travelling belt that can rotate continuously, can solve the short problem of plank like this; 3, the pulling spring balance is made into to make conveyer belt with driven by motor or hand rotation, and travelling belt moves with friction speed, do not influence the size of friction force, makes the teaching aid after the improvement, experiment accurately, demonstrating visual improves the quality of teaching.

Claims

1, a kind of frictional experiment demonstrator, form by transparent spring balance (4), motion frame (13) and platform (6), it is characterized in that: transparent spring balance (4) and motion frame (13) are separately fixed on the table top, transparent spring balance is made up of spring balance (1), the transparent shell that has scale, pulley (5), small sheave (12) and cord (3), spring balance one end is fixed on case top, the other end is installed pointer (2), spring is connected with cord, cord is walked around and is fixed on the bottom-right pulley of housing (5), hangs on the small sheave (12) that is fixed on housing sidewall; The motion frame is made up of framework (7), diaxon roller (11), travelling belt (8) and handle (10), and the diaxon roller is installed on the framework, and travelling belt is enclosed within on the diaxon roller (11), and handle is installed in the termination of an axle roller; On travelling belt, place a wooden slide block (14), by the cord traction of spring balance.