CN1033765A - Precise machining device for parts - Google Patents

Abstract

This device comprises four-bar mechanism (2), and the one bar is fixed on the lathe, and the pivot (26) of another bar (10) and double vibrations device (3) links.The lever (16) of supporting grinding stone (17) is installed on the moving bar (9) with hinge.The perpendicular plane of the rod member (8,10) of wherein hinged four bar machineries (2) and the bus of part to be processed (4) at angle.The axis of four-bar mechanism (2) hinge is vertical with the tangent plane of part to be processed (4) again.Lever (16) axis of (15) the plane formed bus tangent with being positioned at part to be processed (4) that go up to be hinged is parallel.

Description

Precise machining device for parts

The present invention relates to the correct grinding of part, i.e. the precise machining device of part.

The present invention is the most useful to the fine finishining of the eccentric shaft axle journal of roller and ball distance ring, rod journal and trunnion and gear pump and pivot.

Another purposes of the present invention is to make the accurate axle of paper, film processing machine, tape recorder and video tape recorder, and the Precision Machining of the main shaft of high accuracy stock-removing machine.

At present, along with to the improving constantly of parts reliability and life requirement, improved requirement to their crudy.For example, be that in the end the allowance that stays before the procedure is 10 to processing parts durability and the high specification requirement of reliability requirement ... 20 ... micron.The waviness of finished surface and rib degree should not surpass 0.1 ... 0.5 micron, and roughness Ra=0.04 ... 0.02 micron.

The requirement of part processing quality strictness like this forces development and adopts new method for fine finishing and process equipment.

Fine abrasive is carrying out having obtained application widely in the fine finishining to the machine high-precision part.This process is finished by the grinding oilstone that is pressed in surface to be machined, and it produces vibration along the revolving part bus.This process is used for removing the protruding peak of roughness that stays in the last procedure, and guarantees to polish the crystal grain (just when this kind crystal grain is arranged) of oilstone.One of major defect of this process is that the metal removal amount is little by (2 ... 6 microns).Stock removal is little can not to guarantee to remove at one in-process the waviness and the roughness of initial roughness when very big (if) and trough.In addition, little can not to remove the degree of depth that metal produces when grinding be 10 to stock removal ... 20 microns defect layer.The fitting tightly of oilstone working surface and part can not allow metalworking coolant rinses out from the processing district that the processing initial stage produces peels off abrasive particle and grinding.The closeness of the thickness of flour sand layer and its formation and relevant from the degree of processing district flushing, this and grind kinematic parameter, specific pressure, size and the characteristic of oilstone and macroscopical geometry of the composition of metalworking coolant and part relevant, the latter influences the stability of final processing.Grind the specific pressure little (P=0.3 of oilstone to part ... 5 kilograms/centimeter ²) bring the 3rd shortcoming to fine abrasive, promptly in second process segment at the protruding peak of roughness of removing the phase I generation, may produce plastic deformation.

The fine finishining process (SU.A.342753) that is named as the macroscopic view correct grinding is considered to the most perfect.The processing method of rotary body is finished by grinding oilstone, and its edge vibrates with the track that the part to be processed bus does not overlap.This kind track can be a straight line, the bus of it and part (SU.A182015) at angle when processing has the part of straight line bus.Oilstone vibrates along complex track when the seat ring of processing ball bearing.This track forms (SU.A.278453) by oilstone around the swing and the reciprocating motion on the direction that is parallel to seat ring profile tangent line of the axis by the seat ring center of curvature.

Vibrate at angle with the part bus during oilstone processing rotation garden column piece, the working surface of oilstone is that planar section constitutes by side garden cylinder section and central segment, and the radius of side garden cylinder section and the radius of finished surface are equal.When vibrating extreme position, the lateral sections of oilstone working face bump machined surface grinds off protruding peak.In continuous grinding process, remove roughness, metal defect layer, longitudinal ripple, transverse wave, rib degree expeditiously, and partly remove ellipse garden degree.The abrasive particle of planar section tangentially slides along the bus of processing parts, under an angle and the protruding peak of roughness that produces by the lateral sections abrasive particle contact, participate in working angles equally.Surface roughness constantly is improved, and makes roughness reach Ra=0.32 according to grinding oil stone granulate fineness ... 0.16 micron.Reduce the amplitude that vibrates in the process finishing stage, the lateral sections of oilstone is not bumped against with finished surface.The abrasive particle that only is positioned at oilstone working face central segment contacts with part, and they are ground (throwing) light.Because at this moment oilstone is that line contacts with part, stock removal seldom, the remaining protruding peak of roughness generation plastic deformation.This just can guarantee, except having the very big cutting output at the processing initial stage, can also make the roughness on surface very little after processing, the Rz=0.01 micron.The interactional discreteness of oilstone and part, the line of planar section contact and can allow residue and abrasive dust arrange from the processing district effectively, and this has just guaranteed the stability of last processing result.

Existing crankshaft journal fine abrasive device (SU.A.205636), be equipped with two quadric chain one parallelogram on its body: main and auxiliary.An auxiliary tetragonal bar is fixed on the lathe, carries out part processing on it; A main tetragonal bar links with the pivot of hinge and vibrating device.Oilstone is fixed on the tail end of lever, lever with hinge and main parallelogram not in the fixed bar link, oilstone vibrates along the workpiece bus.

The axis of the hinge of parallelogram is parallel with the axis of part, and vibrating device is fixed on the post surface, garden of processing parts by means of pulley.

This device has following shortcoming, it can not with part to be processed axis situation at angle under vibration is passed to oilstone, can not realize that just processing performance is than fine abrasive (с у п e р-φ и н и щ) method for fine finishing (macroscopic view grind) more widely.The axis of parallel-crank mechanism is parallel with the axis of workpiece, can not change the inclination angle of oilstone oscillation trajectory to the workpiece axis.In addition, the dynamic loading of this device is big, produces harmful vibration, the cross section of work piece is distorted, because vibrating device is installed on the pulley of swinging with processing parts, and the housing of this device and vibrating device separates, the former is contained on the pulley, and the latter is contained on the knife rest of lathe.This has just reduced the quality on part processing surface.In addition,, make the vibration of knife rest pass to oilstone, reduced the crudy of piece surface owing to there is not to separate the damper of this device and knife rest.

Task of the present invention is, develop a kind of precise machining device for parts, in this device the hinge type four-link mechanism and and the layout of the lever of its supporting oilstone of connecting to guarantee, the movement locus of oilstone and the bus of workpiece do not overlap, and the shape of oilstone working surface does not change during fine finishining.

The solution of this task is as follows, and in precise machining device for parts, part is fixed on the headstock and tailstock of lathe, and this device comprises the hinge type quadric chain, and wherein a bar is fixed on the lathe; Vibrating device, another root bar hinge-coupled of its pivot and hinge type quadric chain; And the grinding oilstone, it is fixed on the end of lever, and lever fixes on the motion bar of four-link mechanism with hinges fixing; According to the present invention, with have one and perpendicular to the plane of processing parts bus at angle in the bar that is fixed on the joining hinge type four-link mechanism of bar on the lathe at least, this bus coincides at process neutralization it and the contacted straight line of oilstone working surface central segment, simultaneously, the axial line of the hinge of hinge type four-link mechanism is in fact perpendicular to the plane of also passing through above-mentioned bus tangent with processing parts, the axial line of the hinge of lever then is parallel to above-mentioned bus, and is positioned at and processing parts plane tangent and that pass through above-mentioned bus.

The device that is provided can guarantee oilstone with the tangent plane of processing parts in move along the track that coincides of bus of discord processing parts.Oilstone forms its working surface under this motion, this surface portion ground parcel processing parts, and working surface side direction section is made the shape of surface to be machined, and central segment is positioned at wherein.In the grinding oil lapicide makes the mutual bump of surperficial lateral sections and part to be processed, constantly part is ground and cuts, thereby can remove metal defect layer, initial roughness, macroscopical geometrical deviation that a last procedure stays fully, be horizontal and vertical waviness, rib degree, and partly remove not garden degree.When reducing the oilstone vibration amplitude, the lateral sections of working surface discord part interacts, and the abrasive particle and the part that only are positioned at central segment contact.At this moment stopped metal cutting.With the contacted abrasive particle of part bus by blunt and polishing, at this moment, at first carry out micro cutting, then the protruding peak of the roughness generation plastic deformation that forms of initial stage.

The axis of the lever of supporting oilstone and the bus of processing parts are parallel, like this, can keep the shape of its working surface when oilstone is worn, thereby greatly reduce processed waviness and rib degree.

The bar that is fixed on the hinge type quadric chain on the lathe in optimum implementation of the present invention can change its height under the situation that does not change bar position, opposite.Can change the angle of oilstone oscillation trajectory smoothly like this, thereby can carry out having the Precision Machining of part in addition of various hardness and roughness to the part bus.

The radial type quadric chain preferably adopts the hinge type parallelogram.Like this, can be arranged in the arbitrary straight line each other steadily time that grinds oilstone at the volley, oilstone keeps shift reciprocately, thereby can make given parameter keep stable during the processing elongated workpieces.

It is the most reasonable that oilstone is fixed on the lever with hinges fixing, and make the bus of the axis of hinge and work piece perpendicular.Can allow oilstone regulate automatically like this, thereby reduce the vertical waviness and the roughness on part processing surface, improve the quality of finished surface along the bus on part processing surface.

Just can more clearly understand These characteristics of the present invention and other advantages after reading following object lesson and the drawing that provides being provided.

Fig. 1 is a precise machining device for parts sketch of the present invention;

Fig. 2 is a drawing in side sectional elevation, and wherein oilstone supporting sample is securely fixed on the lever;

The locus of oilstone and part when Fig. 3 is part roughing;

Fig. 4 is that the support of this device is fixed on the situation on the lathe;

Fig. 5 is the drawing in side sectional elevation of this device, and wherein the oilstone cramp bar fixes on the lever with hinges fixing;

Fig. 6 is surface roughness Ra and the cutting output δ change curve with the roughing time;

The interactional step of oilstone each active section of surface when Fig. 7,8,9 removes waviness and rib and spends for roughing;

Figure 10 is a concrete device of the present invention, and wherein quadric chain is a parallelogram.

This device comprises pedestal 1, fixed hinge formula quadric chain 2 and vibrating device 3(Fig. 1 on it).Part 4 is carried out accurately machined lathe (not expression on the figure) comprise headstock 5 and tailstock 6 that coaxial line is fixing, part 4 is installed in the middle of them.Hinge type quadric chain 2 comprises bar 7,8,9,10, and they connect with hinge 11,12,13,14.

On the upper boom 9 of hinge type quadric chain 2 by means of hinge 15 truck dead levers 16, end bearing oilstone 17 on it, its is with cramp bar 17 fixing (Fig. 2).

The working surface 18 of oilstone 17 comprises lateral sections 19,20 and central segment 21. Lateral sections 19 and 20 has the shape of part 4 surfaces to be machined.During processing garden post surface, lateral sections 19,20 has the shape of Cylinder, and radius is that the radius R of R ' and workpiece 4 equates that the center of radius R is 22,23, equals the length of oilstone 17 working surfaces 18 central segment 21 apart from l between them.The shape of working surface 18 can be made before part 4 processing, also can make in part 4 process.

The lower beam 7 of quadric chain 2 and pedestal 1 are equipped with cushion block 24 at angle on pedestal 1, bar 7 is installed on the pedestal 1 by it.Have one (being two 8 and 10 in this programme) and plane M (Fig. 3) at angle in the middle of the bar 8 and 10 at least, they all connect with bar 7, the bus 25 of plane M and processing parts 4 is vertical, and bus 25 coincides with part 4 and oilstone 17 working faces 18 central segment 21 contacted lines.The axis of hinge 11,12,13,14 is vertical with plane N in fact, and plane N and part 4 are tangent, and by bus 25.The axis of the hinge 15 of lever 16 is parallel with bus 25.In fact be positioned at plane N.

Vibrating device 3(Fig. 1) comprises pivot 26, its usefulness bar 26 ' connect with the bar 10 of quadric chain 2 with hinge 27,28.In the upper end of bar 9, the back of lever 16 is with cramp bar 17 ' fixed support 29(Fig. 2), simultaneously, support 29 and cramp bar 17 ' between flexible member is housed, as compression spring 30, it with cramp bar 17 ' and oilstone 17 press to processed work 4 together.

The lower end of support 29 and transmission device, promptly pneumatic cylinder 31 connects.

Bar 7 is fixed on the pedestal 1, can be along the Level Change position, and do not change the position of opposite bar 9.

Fig. 4 represents embodiment of the present invention, wherein the cramp bar 17 of oilstone 17 ' be fixed on the lever 16 with hinge 32 and 33.Hinge 32 is vertical with part 4 buses 25 with 33 axis, in fact is positioned at plane N.

Pedestal 1 is by damper 34(Fig. 5) be fixed on the cross slide 35 of lathe, on lathe, carry out the processing of part 4, and pedestal 1 is fixed with double-screw bolt 36 1 nuts 37 and spring washer 38.Damper 34 usefulness tapered dowels 39 are fixed from both sides.

Lathe cross slide 35 is fixed on the longitudinal tool rest 40, can be perpendicular to the axis 41(Fig. 1 that connects headstock 5 and tailstock 6 centers) direction on move back and forth.

The installation of longitudinal tool rest 40 can allow it move back and forth along axis 41.

The work of this device is as follows:

By means of transmission device 31 along arrow 42 around axis 15 rotating levers 16, then with cramp bar 17 ' and oilstone 17 leave the processing district together.Workpiece 4 is fixed on headstock 5 and tailstock 6 top, the axis of workpiece 4 and the lathe axis 41 by headstock 5 and tailstock 6 is overlapped.

According to hinged side lever 8 of the different adjustment quadric chains 2 of workpiece 4 materials and shape and 10 angle of inclination beta ₁And β ₂, its decision oilstone 17 oscillation trajectory is to the squint angle α of workpiece 4 buses 25 ₁

Then, receive on the bar 9, make its axis and the bus 25 of part 4 parallel at the hinge 15 of the truck dead lever on the quadric chain 2 16.After this, mobile cross slide 35 makes the axis of hinge 15 be positioned at plane N.

Be fixed on the lever 16 with the cramp bar 17 of oilstone 17 ' securely (Fig. 2) or with hinge (Fig. 4) according to the length of workpiece 4 and desired precision.

After finishing above operation, carry out the roughing of part 4, part 4 is 41 rotations along arrow 43 around machine axes.

Transmission device 31 turns back to initial position, at this moment, presses arrow 44 rotating levers 16 under the effect of spring 30, and part 4 and oilstone 17 working surfaces 18 are contacted.If the length of part 4 has surpassed the length of oilstone 17, then along axis 41 follow rests 40.Connect vibrating device 3, pivot 26 is reciprocating along arrow 45 and 46.By bar 26 ' bar 10,9,8 is passed in vibration.At this moment, because side lever 8 and 10 is with perpendicular to the plane M of part 4 buses 25 at angle, and around axis 11 and 14 swings, bar 9 is along vibrating with track that bus 25 does not overlap.By hinge 15, lever 16, cramp bar 17 ' oilstone 17 is passed in vibration, simultaneously, oilstone 17 moves along a track, and the tangent line of this track is at oilstone vibration centre position and part 4 buses 25 angled α ₁

Because abrasive particle on the double vibrations working surface 18 of oilstone 17 and part 4 finished surfaces interact.The lateral sections 19 of oilstone 17 working surfaces 18 and 20 abrasive particle are when the vibration mark position and part 4 bump, and the protruding peak of abrasive particle is by sharpening as a result.Carry out the cutting on part 4 surfaces during the protruding peak of blunt abrasive particle.Because each double vibrations at oilstone 17 all has bump in the cycle, so cutting output is continuously all arranged, this point can the figure shows the relation (Fig. 6, curve K, ob section) of roughness Ra and metal cutting amount δ and process time clearly as seen from the figure.The abrasive particle of oilstone 17 working surfaces 18 central segment 21 is equally by sharpening, under an angle and the polishing scratch that forms of the abrasive particle of lateral sections 19,20 collide, and participate in working angles.

Machined surface roughness Ra(Fig. 6 curve H) descends very fast (Oa section) at the initial stage of processing, then in the phase I of whole processing, do not change (ab section).When cutting output reaches certain value, promptly removed the metal defect layer, the degree of depth is 10 ... 20 microns, reduce the vibration amplitude of the pivot 26 of vibrating device 3, promptly grind the stroke of oilstone. Lateral sections 19 and 20 is no longer clashed into part 4, and next step is processed by the abrasive particle on oilstone 17 working surfaces 18 central segment 21.Phase I by processing enters second stage (Fig. 6, bd section).Because the abrasive particle on the central segment 21 with the tangent plane N of part 4 in move, promptly tangentially move along finished surface, the protruding peak of abrasive particle begins by blunt so, cutting output diminish (bc section).At this moment metal stops cutting (curve K) gradually, and surface roughness Ra (curve H) reduces.Then the abrasive particle on oilstone 17 working surfaces 18 central segment 21 is polished, metal stops cutting (curve K go up cd section), is positioned at roughness (seeing the bc section on the curve H) the protruding peak generation plastic deformation (seeing the cd section on the curve H) that produces when high load capacity on the protruding peak of abrasive particle on part 4 and central segment 21 contacts wire makes roughing.The roughness of finished surface reduces, Ra=0.05 ... 0.01 micron.

Lateral sections 19 and 20(Fig. 7,8 on oilstone 17 working surfaces 18) and the alternately bump on the surface of rotating part 4 and removed the rib degree of the horizontal waviness above the garden 47 in the continuous cutting at processing initial stage, the center in garden 47 is at the center of processing parts 4, and radius is R ¹, it equals the distance by concavity bosom 48 of waviness or rib degree to part 4 finished surfaces, above-mentioned center.Central segment 21(Fig. 9) waviness and rib degree itself have been removed in the interaction of the raised section of waviness and rib degree in working angles continuously and on the revolving part 4.This just can be when roughing, and initial value is under 10 microns the situation, removes transverse edge degree and waviness to 0.1 micron.

Reach after desired metal cutting amount and the given roughness, roughing stops.Press arrow 42 rotating levers 16 by transmission device 31 for this reason, oilstone 17 is left from workpiece 4.

The part of processing difform and various material manufacturing changes the squint angle β of 8,9 couples of plane M of bar ₁And β ₂Second position on Fig. 1, having represented hinge type quadric chain 2 with fine rule.For this reason, upper boom 9 is motionless, unclamps lower beam 7 from pedestal 1, extracts pad 24 out, bar 7 is moved up, and be β up to squint angle to plane M ₃And β ₄Till.

Then, load onto another cushion block 49, barre 7 is fixed on the pedestal 1 again.The track vibration that oilstone 17 did not overlap by the bus 25 with part 4 when hinge type quadric chain 2 was passed in vibration, part tangent line and 25 one-tenth α of bus when being in the vibration centre position ₂The angle.

The hinge type four-link mechanism 2 of having represented parallel four limit lines on Figure 10, lower beam 7 is fixed on the pedestal 1 by cushion block 24, and like this, bar 7 just is parallel to the bus 25 of processing parts 4.The operation principle of this device is the same with above-mentioned quadric chain 2.

Each root bar is parallel to each other mobile when adopting parallel four limit row mechanisms can guarantee oilstone 17 motions.Central segment 21 has the shape of rectangle when moving, this just can improve vertical macroscopical geometrical precision of part 4.

Result of the test of the present invention shows, this device is 100 millimeters at the processing diameter, and when length was 25 millimeters the hardened face of part, the cutting output of metal was 15 in 30 seconds ... 20 microns, vertically waviness is 0.5 micron, and roughness is Ra=0.04 ... 0.02 micron.

Claims (4)

1, this device is used for the machine components that are contained on the lathe head of a bed and the tailstock are carried out fine finishining, and it comprises four-bar mechanism (2), and its rod member (7) is fixed on the lathe; Double vibrations device (3), its vibration pivot (26) links with hinge with the rod member (10) of four-bar mechanism; Be contained in the grinding stone (17) of lever (16) end, the other end of lever is hinged on the movable rod member (9) of four-bar mechanism (2), this apparatus features is, in the four-bar mechanism (2) be fixed on lathe on rod member (7) connecting two bar rod member (8) and (10), wherein has one and plane (M) group at least at an angle, the bus (25) of plane (M) and part to be processed (4) is perpendicular, in the process of central sections (21) processing parts (4) of going up working face (18) with grinding stone (17), bus (25) coincides with the contact wire of part (4), in addition, hinge (11 on the four-bar mechanism (2), 12,13,14) axis is in fact vertical with plane (N), plane (N) is tangent with part to be processed (4) again, and by bus (25), and the axis of lever (16) upper hinge (15) is parallel with bus (25), in fact is positioned at the plane (N) that is cut in part (4) and passes through bus (25).

2, according to claim 1, this apparatus features is that the rod member (7) that is fixed on the lathe can be mounted to the possibility that has by Level Change itself position under the situation of bar (9) position that does not change four-bar mechanism king-rod (7) opposite side.

3, according to claim 1 and 2, this apparatus features is that four-bar mechanism (2) can adopt the parallelogram four-bar mechanism.

4, according to claim 1, this apparatus features is, grinding stone (17) is installed on the lever (16) with hinge, and hinge (32,33) axis normal is in the bus (25) that is added part (4), in fact also be positioned at part (4) tangent, and by in the plane (N) of bus (25).

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