CN101270974A - Analogy method and measuring apparatus for elastohydrodynamic lubricant film shape experiment with self-spin - Google Patents

Abstract

The invention discloses an experimental simulation method of elastic-hydrodynamic oil film shape with spin, which is characterized in that different spin weight and ratio of revolution and rolling are obtained through adjusting the eccentric distance between the contact center of a contacting body and a glass block and the rotation center of the glass block. The invention has advantages of accurate positioning, which can simulate spin elastic-hydrodynamic oil film shape. The device has simple and reasonable structure and low cost.

Description

The elastohydrodynamic lubrication oil film shape experimental simulation method and the measurement mechanism that have spin

Technical field

The invention belongs to the experiment measuring field of point, line contact elastohydrodynamic lubrication oil film shape, relate in particular to the measurement of the elastohydrodynamic lubrication oil film thickness that has automatic rotary component.

Background technology

Elastohydrodynamic lubrication (elastohydrodynamic lubrication) is many points in the engineering, the common lubricated form of line contact parts, as lubricating of rolling bearing and gear etc.The shape of elastohydrodynamic lubrication oil film and thickness are the important indicators of estimating lubricated validity, in engineering practice and scientific research consequence are arranged.In the engineering analysis and research of general elastohydrodynamic lubrication, the motion of two surface in contacts is assumed to relative rolling and slip usually.Yet in some cases, also there is spin in surface in contact.Because the existence of contact angle, spin motion can take place in steel ball, produces bearing wear and inefficacy as the steel ball of angular contact ball bearing and lasso.In mechanical stepless speed change (CVT), two rolling body axes intersect are not parallel, also can produce the surface in contact spin, reduce the transmission efficiency of CVT.

The experimental study that has the elastohydrodynamic lubrication of spin mostly concentrates on the measurement of moment and the measurement of oil film shape and thickness.Its key issue be the laboratory of elastohydrodynamic lubrication under the spin condition reproduce-be the experimental simulation method.The experimental simulation device that relates to the elastohydrodynamic lubrication that spins commonly used at present comprises:

1, ball-groove contact

Fig. 2 is ball-groove contacting structure sketch.Be processed with the groove that xsect is a circular arc on the full pattern 1, sample 2 is a steel ball with high precision.During experiment, sample 2 contacts at trench bottom under loading with sample 1, and sample 1 is static, and sample 2 rotates.Such device has only pure spin, does not roll or the slip component, can not spin and this common situation of rolling/sliding and depositing in the model engineering reality.

2, spheric disk-cylinder disk contact

Fig. 3 is the structure diagram of this type of measurement mechanism.It is made up of a spheric disk sample 1 and a cylinder group dish sample 2.Two dishes all center on axle center rotation separately.Can adjust the axis of spheric disk and the angle of cut α of cylinder disk axis in the experiment, to obtain different automatic rotary components.

3, ball-dish contact

Fig. 4 as can be seen from the figure, obtain different automatic rotary components for another experimental technique commonly used, needs to regulate the contact angle θ of steel ball and disk.Usually disk is the clear glass dish, can realize the measurement of oil film shape and thickness.

More than in the existing analogy method, introduce spinor by the adjusting of friction pair two surperficial turning axle angles.The accurate adjusting of this angle needs comparatively, and complicated apparatus realizes.

Summary of the invention

The objective of the invention is the deficiency at prior art, a kind of experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin is provided, this method is simply effective, and simulation accurately.

Another object of the present invention provides a kind of experimental simulation device that has the elastohydrodynamic lubrication oil film shape of spin, and this apparatus structure is simple, and simulation accurately.

Below introduce the present invention in detail, a kind of experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin obtains different automatic rotary components and revolves to roll ratio by the center that contacts and the eccentric throw of glass blocks rotation center of adjusting contact and glass blocks.

Optimally, utilize the crooked significantly air pocket track in bullet stream exit, Contact Pair contact region to carry out curve simulation, accurately determine the rotation center position of glass blocks.

Another technical scheme of the present invention is a kind of experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin, and test ball contacts with the one side that being coated with of transfer glass analysed the light film, analyses light film surface and scribbles lubricating oil; Test ball and glass blocks can rotate respectively, form bullet stream oil film in the contact region; Use bidimensional translation combination, the distance of regulating steel ball and center, glass blocks contact region and glass blocks rotation center just can obtain the elastohydrodynamic lubrication under the different automatic rotary component conditions.

Optimally, the rotation center of glass blocks is sought by lubricated cavity track.

Optimally, lubricated cavity track utilizes the crooked significantly air pocket track in bullet stream exit, Contact Pair contact region to carry out curve simulation, accurately determines the rotation center position of glass blocks.

Optimally, test ball is steel ball or spherical roller or cylindrical roller.

Another technical scheme of the present invention is a kind of experimental simulation device that has the elastohydrodynamic lubrication oil film shape of spin, comprises bullet stream contact portion, loading section and optical measurement part, and its stream contact portion of being hit by a bullet comprises test ball, and this test ball is provided with turning axle; Test ball contacts with the one side that being coated with of transfer glass analysed the light film, analyses light film surface and scribbles lubricating oil; The end face of test ball contacts with transfer glass, this test ball is installed on the two-dimension translational platform of surface level, described optical glass connects the surface level wheelwork, and this surface level wheelwork is provided with at the optical glass place and detects the hole, and data extraction device detects the hole by this and extracts imaging data.

Advantage of the present invention is to be decided to be accurately, can simulate the elastohydrodynamic lubrication oil film shape of spin, this apparatus structure advantages of simple simultaneously, and cost is low.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the contact form of a kind of analogue means before the present invention;

Fig. 3 is the contact form of the another kind of analogue means before the present invention;

Fig. 4 is the contact form of the another kind of analogue means before the present invention;

Fig. 5 is a method schematic diagram of the present invention;

Fig. 6 is that the cavitation track of glass blocks rotation center of the present invention is determined the method synoptic diagram;

Fig. 7 is an experimental provision stereographic map of the present invention;

Fig. 8 is a structural representation of transferring the device that inclines;

Fig. 9 is a pure spin interference pattern under the different rotating speeds;

Figure 10 is the influence of eccentric throw r to thickness;

Figure 11 is the structural representation of charger.

Embodiment

Embodiment 1:

Basis of the present invention is a kind of experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin, obtains different automatic rotary components and revolve to roll ratio by the center that contacts and the eccentric throw of glass blocks rotation center of adjusting contact and glass blocks.Utilize the crooked significantly air pocket track in bullet stream exit, Contact Pair contact region to carry out curve simulation, accurately determine the rotation center position of glass blocks.

A kind of specifically experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin, test ball contacts with the one side that being coated with of transfer glass analysed the light film, analyses light film surface and scribbles lubricating oil; Test ball and glass blocks can rotate respectively, form bullet stream oil film in the contact region; Use bidimensional translation combination, the distance of regulating steel ball and center, glass blocks contact region and glass blocks rotation center just can obtain the elastohydrodynamic lubrication under the different automatic rotary component conditions.The rotation center of glass blocks is sought by lubricated cavity track.Lubricated cavity track utilizes the crooked significantly air pocket track in bullet stream exit, Contact Pair contact region to carry out curve simulation, accurately determines the rotation center position of glass blocks.

See also Figure of description 1 and accompanying drawing 7, originally the concrete structure of experimental simulation device that has the elastohydrodynamic lubrication oil film shape of spin is, one framework 10 is set, the two-dimension translational platform 20 of surface level is installed on the base 11 of this framework, installation testing ball 30 devices on this two-dimension translational platform, described test ball is provided with the rotating shaft 31 of level; The bottom surface of the top contact optical glass 40 of test ball 30, this optical glass connects slewing equipment 50, and slewing equipment 50 connects propulsion system by synchronous pulley 60, and described two-dimension translational platform 20 is provided with a micromatic setting 21 and thick strip device 22; Wherein micromatic setting 21 is arranged on a charger 70 that is used to regulate the bottom surface contact pressure of test ball 30 and optical glass 40; Slewing equipment is the structure of hollow, and camera head 80 and microscope 90 are arranged in the space of slewing equipment, and just in time is in the position that is fit to take test ball 30.

See also Figure of description 11 described chargers 70 a loading supporting plate 71 is set, an end that loads supporting plate 71 is provided with hinge, the other end is installed on the loader 72, this loader 72 is provided with a support 721, spring 722 is set on the support, spring 722 connects loading supporting plate 71, and the other end of spring is rack-mount by tautness meter, and the top of support is provided for the adjusting handle 723 that regulating spring stretches and shrinks.

See also Figure of description 7 and accompanying drawing 11

Described two-dimension translational platform 20 comprises micromatic setting 21 and thick strip device 22, and micromatic setting is arranged on the rack and rinion adjustment, and rack and rinion adjustment 22 is provided with a slide plate 221, track 222 is set below the slide plate, and adjusting handle 223 is set; Micromatic setting 21 is that a two dimension is reconciled the platform 211 two-way tracks that all are provided with, and both direction all is provided with adjusting handle 212.

See also the general structure synoptic diagram of Figure of description 7 invention experimental provisions.Device comprises three two parts:

Part I-bullet flows the Contact Pair part, transfers structure such as Fig. 8 of the device that inclines, is specifically designed to the experiment of cylindrical roller line contact.This device is connected in and loads on planker Fig. 7, and cylindrical roller is adjusted automatically during loading, has guaranteed contacting fully of the homogeneity that loads and cylindrical roller and glass disc.Handwheel and slide plate are used for the coarse adjustment of Contact Pair position.The detailed structure of remainder is referring to Fig. 1.

Part II-loading section.Rotating afterburning screw rod can realize loading.The digital display tautness meter is connected by spring with the loading supporting plate realizes flexible the loading.

Part III-optical measurement part, microscope are coaxial-illuminating continuous zoom monotubular videomicroscopy.Incident light enters bullet stream contact region through the coaxial-illuminating device, and image card is captured and passed to interference pattern by camera head after microscope amplifies, handled by image processing software, obtains oil film thickness.

It is steel ball, spherical roller or cylindrical roller that this experimental provision visual exam requires to select the contact of glass blocks.

See also Fig. 5; The new experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin.

The new test simulation method of being invented and the principle of corresponding intrument are as shown in Figure 5.Glass blocks rotates with angular velocity omega around rotation center O '.With steel ball-glass blocks contact is example, and the contact region is a circle, and some O is its center.According to requirement of experiment, steel ball or static or rotation.For any point of crossing on arbitrary the straight line (as OA among Fig. 5) that O orders (as the A point), its speed u=r ₁ω, r ₁=| O ' A|.Naming a person for a particular job at A, this speed is decomposed into the u1 that is parallel to the y axle and perpendicular to the u2 of OA, then u1 and u2 satisfy

$\left\{\begin{array}{c}{u}_1=r\·\mathrm{\ω}\\ u_2=r_2\·\mathrm{\ω}\end{array}\right.---\left(1\right)$

Can see that along the speed component u1 of y axle be constant, not rely on the position that A is ordered.And be directly proportional to the distance that contacts the center with the A point perpendicular to the speed component u2 of radial line.Can see that the motion of glass blocks equivalence is for touching the rotation u2 of center O along the axial translation u1 of y and solderless wrapped connection.Translation u1 causes entrainmenting of common lubricating oil, rotates u2 and is spin.

In the experiment, establishing the steel ball radius is that the speed of Rb on the surface, contact region is ub, along the Entrainment Velocity of y axle

$u_e=\frac{u_1+u_b}{2},$ Revolve and roll than being calculated as follows

$S_{\mathrm{sp}}=\frac{R_b\mathrm{\ω}}{u_e}---\left(2\right)$

This device can be realized pure cunning and the pure two states that rolls.

During pure rolling, u ₁=u _b, $S_{\mathrm{sp}}=\frac{R_b}{r};$ Pure when sliding, u _b=0, $S_{\mathrm{sp}}\text{=}\frac{{2R}_b}{r}.$

[proof:

Straight line O ' A equation: y=xtan α; Straight line OA equation: y=-tan β (x-r);

Can obtain:

$\left|O^{\′}B\right|=\frac{r\tan \mathrm{\β}}{\tan \mathrm{\α}+\tan \mathrm{\β}}=\frac{\cos \mathrm{\α}\sin \mathrm{\β}}{\sin (\mathrm{\α}+\mathrm{\β})}\·r,$

$r_1=\frac{\left|O^{\′}B\right|}{\cos \mathrm{\α}}=\frac{\sin \mathrm{\β}}{\sin (\mathrm{\α}+\mathrm{\β})}\·r$

$r_2=r_1\·\frac{\sin \mathrm{\α}}{\sin \mathrm{\β}}=\frac{\sin \mathrm{\α}}{\sin (\mathrm{\α}+\mathrm{\β})}\·r$

Speed u is

$u=r_1\·\mathrm{\ω}=\frac{\sin \mathrm{\β}}{\sin (\mathrm{\α}+\mathrm{\β})}\·r\·\mathrm{\ω}$

U1 equates with the projection of u on AO,

$u_1\·\cos (\frac{\mathrm{\π}}{2}-\mathrm{\β})=u\·\cos (\mathrm{\α}+\mathrm{\β}-\frac{\mathrm{\π}}{2})$

$u_1=u\·\frac{\sin (\mathrm{\α}+\mathrm{\β})}{\sin \mathrm{\β}}=r\·\mathrm{\ω}$

U2 equates with the projection of u on the x axle,

$u_2\·\cos (\frac{\mathrm{\π}}{2}-\mathrm{\β})=u\·\cos (\frac{\mathrm{\π}}{2}-\mathrm{\α})$

$u_2=\frac{u\·\sin \mathrm{\α}}{\sin \mathrm{\β}}=\frac{\sin \mathrm{\α}}{\sin (\mathrm{\α}+\mathrm{\β})}\·r\·\mathrm{\ω}=r_2\·\mathrm{\ω}$

Finish]

The cavitation track that sees also Figure of description 6 glass blocks rotation centers is determined method

One of key issue in the experiment is that the accurate of rotation center position after glass blocks is installed determined.At first suitably regulate microscopical enlargement factor, find the interference image when static.Apply certain load, rotate glass blocks, can observe the air pocket track in bullet stream exit, Contact Pair contact region.The position that utilizes the bidimensional translation stage to move spherical roller (or steel ball) can obtain crooked significantly air pocket track very easily.The Graphics Application process software can accurately be determined the rotation center position of glass blocks.

4 working of an invention processes

Select contact by experiment purpose, determine experiment parameter by the formula (2) in the summary of the invention 1 (the new experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin).

By requirement of experiment locking or loosen the contact revolving shaft, realize sliding or rolling.

Press the selected velocity parameter by the slewing equipment of band driving synchronously, apply predetermined load by afterburning screw rod and digital display tautness meter.

Determine the glass blocks centre of gyration by summary of the invention 2 (the cavitation track of glass blocks rotation center is determined method).

Use the bidimensional translation stage and regulate the contact position, realize predetermined r.

Experiment beginning, images acquired and handling behind the velocity-stabilization.

Can realize the present invention well according to above step.

5 experiment measuring examples

Accompanying drawings measurement result of the present invention:

1) pure spin measurement result, i.e. r=0.Adopt oval contact, interference pattern such as accompanying drawing 9 under the pure spin situation that records, along with the increase of rotating speed, air pocket is expanded to outlet area from the lubricating oil inlet district gradually, finally links together.The appearance of air pocket has proved the formation of oil film thickness, and the expansion of air pocket has caused the not generation of foot phenomenon of fuel feeding.

2) revolve sliding measurement result.Adopt the steel ball and the mode of glass blocks contact to record the oil film interference pattern of different eccentric throw r, as can be seen, along with the increase of eccentric throw, the influence of being spinned dies down, and the oil film asymmetry reduces.See also accompanying drawing 10.

Claims (10)

1, a kind of experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin is characterized in that; Obtain different automatic rotary components and revolve to roll ratio with the eccentric throw of glass blocks rotation center by the center that contacts of adjusting contact and glass blocks.

2, the experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin according to claim 1 is characterized in that; Utilize the crooked significantly air pocket track in bullet stream exit, Contact Pair contact region to carry out curve simulation, accurately determine the rotation center position of glass blocks.

3, a kind of experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin is characterized in that; Test ball contacts with the one side that being coated with of transfer glass analysed the light film, analyses light film surface and scribbles lubricating oil; Test ball and glass blocks can rotate respectively, form bullet stream oil film in the contact region; Use bidimensional translation combination, the distance of regulating steel ball and center, glass blocks contact region and glass blocks rotation center just can obtain the elastohydrodynamic lubrication under the different automatic rotary component conditions.

4, the experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin according to claim 3 is characterized in that; The rotation center of glass blocks is sought by lubricated cavity track.

5, the experimental simulation method that has the elastohydrodynamic lubrication oil film shape of spin according to claim 4 is characterized in that; Lubricated cavity track utilizes the crooked significantly air pocket track in bullet stream exit, Contact Pair contact region to carry out curve simulation, accurately determines the rotation center position of glass blocks.

6, according to claim 3 or the 4 described experimental simulation methods that have the elastohydrodynamic lubrication oil film shape of spin, it is characterized in that; Test ball is steel ball or spherical roller or cylindrical roller.

7, a kind of experimental simulation device that has the elastohydrodynamic lubrication oil film shape of spin comprises bullet stream contact portion, loading section and optical measurement part, it is characterized in that; Its stream contact portion of being hit by a bullet comprises test ball, and this test ball is provided with turning axle; Test ball contacts with the one side that being coated with of transfer glass analysed the light film, analyses light film surface and scribbles lubricating oil; The end face of test ball contacts with transfer glass, this test ball is installed on the two-dimension translational platform of surface level, described optical glass connects the surface level wheelwork, and this surface level wheelwork is provided with at the optical glass place and detects the hole, and optical measurement partly detects the hole by this and extracts imaging data.

8, the experimental simulation device that has the elastohydrodynamic lubrication oil film shape of spin according to claim 7 is characterized in that; The concrete structure of this analogue means is, a framework (10) is set, and the base of this framework (11) is gone up the two-dimension translational platform (20) that surface level is installed, installation testing ball (30) device on this two-dimension translational platform, and described test ball is provided with the rotating shaft (31) of level; The bottom surface of the top contact optical glass (40) of test ball (30), this optical glass connects slewing equipment (50), slewing equipment (50) connects propulsion system by synchronous pulley (60), and described two-dimension translational platform (20) is provided with a micromatic setting (21) and thick strip device (22); Wherein micromatic setting (21) is arranged on a charger (70) that is used to regulate the bottom surface contact pressure of test ball (30) and optical glass (40); Slewing equipment is the structure of hollow, and camera head (80) and microscope (90) are arranged in the space of slewing equipment, and just in time is in the position that is fit to take test ball (30).

9, the experimental simulation device that has the elastohydrodynamic lubrication oil film shape of spin according to claim 8 is characterized in that; Described charger (70) is provided with one and loads supporting plate (71), an end that loads supporting plate (71) is provided with hinge, the other end is installed on the loader (72), this loader (72) is provided with a support (721), spring (722) is set on the support, spring (722) connects loading supporting plate (71), and the other end of spring is rack-mount by tautness meter, and the top of support is provided for the adjusting handle (723) that regulating spring stretches and shrinks.

10, the experimental simulation device that has the elastohydrodynamic lubrication oil film shape of spin according to claim 8 is characterized in that; Described two-dimension translational platform (20) comprises micromatic setting (21) and thick strip device (22), and micromatic setting is arranged on the rack and rinion adjustment, and rack and rinion adjustment (22) is provided with a slide plate (221), track (222) is set below the slide plate, and adjusting handle (223) is set; Micromatic setting (21) is that a two dimension is reconciled the two-way track that all is provided with of platform (211), and both direction all is provided with adjusting handle (212).

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