CN102562836B - Shaft and rod micro-clearance direct-connection technology - Google Patents

Abstract

The invention relates to a micro-interval shaft lever direct connection method which reserves intervals at the connection of the shaft and the lever, thus eliminates the deviation caused by offset and an included angle between a shaft central line and a lever central line, eliminates the deviation caused by shaft radial direction jump and axial direction endplay, eliminates the bad factors brought by assembly location deviation, enables the lever not to shake and not to generate the bad reaction force, and greatly improves the transmission stability and efficiency. It is important to obtain the reserved intervals. Though interference fit of the shaft lever, the farthest end shaking amplitude of the lever is measured after running, namely the shaking maximum diameter is R, the lever length is set as L, alpha is obtained according to tg alpha=R/2L, the length of the shaft into the lever is set as x, then the reserved interval r of the shaking part is x*sina alpha, the alignment deviation caused by the assembly is set as y, then the minimum interval between the shaft and the lever is x*sina alpha+2y, and normally unpredictable interval z of 0.01-0.05mm is also needed to improve the reliability.

Description

The direct-connected method of a kind of microgap axostylus axostyle

Technical field

The present invention relates to mechanical transmission fields, be applied to space there are certain requirements, and need to reduce the situation of energy loss.

Background technique

Along with improving constantly of mechanical automation degree, mechanical transmission becomes requisite key element, and the efficiency of transmission, complexity, reliability, the focus that has become everybody to pay close attention to, the more common kind of drive has: band transmission, chain transmission and gear transmission, feature is to carry out transmission and the break-in of power, the vibration while simultaneously alleviating transmission and deviation.Yet all there is intermediate structure, situation for limited space, just more difficult, it is exactly typically the transmission of power of motor transmission shaft and stock, whether feasiblely directly transmission shaft is connected with stock? facts have proved, all there is a little shake (circular runout) in transmission shaft, once and be connected with stock, this shake is by increase at double, the Concentricity tolerance of connection part is also the key factor that causes stock to rock, and stock far-end is fixed with bearing, because electric machine support also exists certain deviation, during electric machine rotation because stress certainly leads to very large resistance, thereby efficiency reduces greatly, motor damage even.Current solution is to adopt elastic coupling flexible coupling, can effectively solve like this axostylus axostyle decentraction or have the transmission problem of augular offset.Yet elastic coupling flexible coupling needs certain space support, for specific environment, still cannot use.How in limited space, to realize axostylus axostyle transmission of power, and eliminate medium tache, the key that has become us to overcome.

Summary of the invention

The object of the invention is a kind of method by easy realization, with minimum structure, carry out axostylus axostyle transmission of power, and the direct-connected method of a kind of microgap of called after axostylus axostyle.Method is that rod end is made to the hole of mating with axle, requirement axle is non-cylindrical (as D shape, two D shape), the cambered surface center of circle in hole is concentric with bar, preset clearance between hole and axle, thereby elimination shaft centre line and bar center line exist and depart from the deviation causing with angle, eliminate the deviation that axle circular runout, axial float cause, eliminate the undesirable element that assembling and positioning deviation etc. is brought, solved the problem that error that axle and stock be directly connected appearance increases progressively at double.

Although fine finishing at present can realize the precision of um level, is to be all based upon on expensive basis.Conventional motor shaft run-out, for the following diameter of axle of 10mm, beat for 20um, the long 5mm of Motor Shaft for example, the long 60mm of bar, by the 20um calculating of beating, gets rid of other error components, carry out interference fit connection, to occur the wow and flutter of rod end 0.24mm, if bar further lengthens, that wow and flutter degree will be multiplied.Facts have proved, axostylus axostyle directly connects, the concentricity of rod end wow and flutter and connection part, the angularity relation of bar is more close, the high order of magnitude of wow and flutter that the wow and flutter producing causes than circular runout sometimes, in addition, there is the problem of centering and angulation in assembling, shaft centre line and bar center line exist and depart from and angle, and angle impact is larger, for example, during 1 ° of (accompanying drawing 2) angle, bar length is still 60mm, and that wow and flutter is 2*tg1 ° * 60, about 2mm, these a series of error components stack up, and will make wow and flutter large to the stage can not put up with.And microgap axostylus axostyle direct-connecting technology, by axle and bar joint, preset clearance, thereby eliminate aforementioned error component, make bar there is no wow and flutter, and no longer produce bad stress, also eliminated the axial float of axle simultaneously, transmission stability and efficiency are improved greatly, and owing to being direct-connected, space hold has reached lowest limit.Gap connects can adopt D profile shaft or flat axle, and gap length is very important, too little shake and the stress cannot eliminated completely, and too senior general produces excessive return difference gap, and easily occurs beating.The size in gap draws like this: owing to directly measuring ten minutes difficulties of angle α that shaft centre line and bar center line exist, therefore first by axostylus axostyle interference fit, after operation, record bar distal-most end wow and flutter amplitude, be wow and flutter maximum diameter R, if bar is long, be L, according to tg α=R/2L, obtain α value (accompanying drawing 1), if the length that axle enters in bar is x, the preset clearance r of wow and flutter part is x*sin α, if the alignment deviation that assembling causes is y, the minimum clearance between bar and axle is x*sin α+2y, conventionally also need to increase by the unpredictable gap z (as machining tolerance etc.) of 0.01～0.05mm.If wow and flutter R is 2mm, the long L of bar is 60mm, axle and the long 5mm of bar linkage section X, calculating α is 1 ° (accompanying drawing 2), according to r=x*sin α, obtains the about 0.09mm of preset clearance r, if alignment deviation y is 0.03mm, increasing unpredictable gap z is 0.02mm again, the gap that must need is 0.17mm, if the diameter of axle is 3mm, connecting rod aperture should be 3.17mm.Facts have proved, the direct-connected transmission effect of axostylus axostyle obtaining is in this way comparatively desirable, can eliminate preferably wow and flutter and beat.

Accompanying drawing explanation

Accompanying drawing 1 is the sectional view that axostylus axostyle connects, and R is wow and flutter maximum diameter, and L is that bar is long, and α is bar center line and shaft centre line angle, and x is that axle enters the length in bar, and r is for eliminating the required preset clearance (r=x*sin α) of wow and flutter, the alignment deviation that y causes for assembling.

Accompanying drawing 2 is that the result of calculation of the concrete numerical value of sectional view of axostylus axostyle connection embodies.

Embodiment

Typical application is exactly the mechanical transmission component of " automatic instrument for measuring fascia pressure ", automatic instrument for measuring fascia pressure is a kind of equipment of special measurement manadesma chamber pressure, be mainly used in orthopaedics, because space is less, and powered battery, it has adopted minitype speed reducing motor 3mmD profile shaft and 5mm screw rod to carry out direct-connected, adopt this technology to save transmission intermediate structure, by preceding method, calculating preset clearance is 0.12mm, facts have proved reliable, can effectively eliminate bad stress and wow and flutter, space hold reaches lowest limit, and loss is low.This instrument does not require return difference, and practical effect is very good.

This be a kind of be conserve space, the method of power transmission reducing costs again, really solve axle and be connected the problem that the error that occurs increases progressively at double with stock, error and the bar of realizing transmission of power are long irrelevant, owing to there is no medium tache (as sprocket wheel, belt wheel, gear), therefore power loss is little, and energy saving is applicable to the equipment to power consumption sensitivity.Owing to having adopted the microgap error that disappears, therefore there is return difference gap, it is not suitable for the equipment that return difference is had to strict demand.

Claims (1)

1. the direct-connected method of microgap axostylus axostyle, it is characterized in that rod end to make the hole of mating with axle, by by this borehole jack, the mode on axle is connected bar with axle, requiring axle is the non-cylindrical configurations of D shape or two D types, the cambered surface center of circle in hole is concentric with bar, preset clearance between hole and axle, wherein the size of preset clearance is calculated acquisition by the following method, first by axostylus axostyle interference fit, after operation, record bar distal-most end wow and flutter amplitude, be wow and flutter maximum diameter R, if bar is long, be L, according to tg α=R/2L, obtain α value, if the length that axle enters in bar is x, the preset clearance r of wow and flutter part is x*sin α, if the alignment deviation that assembling causes is y, the minimum clearance between bar and axle is x*sin α+2y, conventionally also needing increases for revising the unpredictable gap z of machining tolerance, wherein the value of unpredictable gap z is 0.01mm～0.05mm.