Crankshaft key slot processing and detection method
The present invention relates to a kind of processing and detection method of mechanical transmissioning piece, especially a kind of crankshaft key slot processing and detection method belong to the Machining Technology field.
Understand according to the applicant, the big machinery drive apparatus all has strict demand to the two keyways of the trunnion of used bent axle usually to the symmetry on crank throw center and trunnion line of centres plane.At present, adopt crankshaft grinding machine that the bent axle of producing in batches is carried out fine finishining usually.But, large-scale nonstandard bent axle for jobbing work, make and have very big difficulty, not only because large-scale crankshaft grinding machine scarcity of resources, equipment investment expense costliness, and keyway adds center line and trunnion line of centres plane that be difficult to detect the accurate crank throw of centering man-hour, thereby makes the keyway symmetry of processing be difficult to reach designing requirement, and the processing back is difficult to accurately detect the symmetry of keyway.
As depicted in figs. 1 and 2, analyze as can be known a little, when the two keyways that require to be positioned at main bearing journal 1 are 0.045mm to the symmetry of crank throw journal centre and trunnion line of centres O1-O2, theoretical and practice all proves, looks for the way of high point to be difficult to accurately find crank throw peak position by tradition with amesdial.In fact, often there are very big deviation in crank throw center and the trunnion line of centres plane of looking for the way of high point to find with amesdial, and this deviate might be much larger than the required value of the symmetry of keyway.Its reason can illustrate by the example of Fig. 3, for the diameter of axle of R=200mm, is Δ=R-(R leaving the theoretical level difference that high point ± 0.5mm (being L=1mm) locates
1/2=0.0006mm.That is to say, when measuring with amesdial in the scope of L=1mm amesdial reading no change, any point wherein all might be regarded as high point, and maximum deviation might be more than 1mm, and this deviation is considerably beyond the order of magnitude of the symmetry 0.045mm of keyway.Therefore, " benchmark " that finds with this method can't guarantee precision when processing the symmetry of keyway and detection keyway.
Summary of the invention
The objective of the invention is to: at the problem that above-mentioned prior art exists, propose a kind of crankshaft key slot processing and detection method, this method is not only easy and simple to handle, and feasible degree is high, thus a difficult problem that solves large-scale crankshaft key slot processing and detect.
In order to achieve the above object, crankshaft key slot of the present invention processing and detection method may further comprise the steps:
The first step, two contour reference blocks that upper and lower faces is parallel of manufacturing;
Second step, on an end face of two reference blocks, process at least two centre bores (centre bore quantity depend on crank throw number) of spacing and line of centres consistent respectively perpendicular to upper and lower surface with trunnion and crank throw distance between journal centers;
The 3rd the step, process shaft-end positioning structure respectively in the other end of two reference blocks, and by shaft-end positioning structure make two reference blocks respectively correspondence fixedly secure at crankshaft two end to be processed;
The 4th goes on foot, locatees on rotating machine with each respective central holes on the reference block of two ends respectively, and rotation processes satisfactory trunnion and crank throw axle journal;
The 5th step, be benchmark, on the keyway machining tool, process the keyway on the trunnion with the upper and lower plane of the reference block at two ends;
The 6th step, be detection reference, detect utensil, detect the symmetry of keyway for the crank throw journal centre and the trunnion line of centres by angle square that relies on trunnion and spacing with the upper and lower plane of the reference block at two ends.
The present invention reasonably adds the auxiliary base piece of processing detection and location with keyway by two whiles as rotation, realized the technology of correct grinding crankshaft journal on common cylindrical grinder, not only guarantee the precision and the position degree of centre bore easily, and reduced requirement to machining tool, need not expensive large-scale crankshaft grinding machine.In addition, when processing and detection keyway, as the auxiliary datum plane that guarantees symmetry, as long as the two ends auxiliary base piece that has ground the bent axle behind the axle journal is placed on the processing keyway with on the workbench of lathe, do not need height and horizontal direction centering, the trunnion and the crank throw axle journal line of centres can be guaranteed perpendicular to work top, thereby keyway can be directly processed.During detection,, very convenient as long as by the general measure utensil such as angle square, slide measure (or micrometer).
In a word, the present invention is by setting up the way of auxiliary base on axle head, just can the Precision Machining bent axle on general cylindrical grinder when not only utilizing this auxiliary base to realize that nonstandard single and mini-batch production is produced, and utilize this auxiliary base to finish accurate processing and the accurate crankshaft key slot of measuring, guarantee that its symmetry reaches designing requirement, thereby the difficult problem that crankshaft key slot processing is detected is readily solved.Theory and practice proves, this method precision height, with a high credibility can duplicate measurements before reference block removes, and method is easy, cost is low.The present invention is equally applicable to the processing and the detection of medium and small nonstandard crankshaft key slot.
Description of drawings
The present invention is further illustrated below in conjunction with accompanying drawing.
Fig. 1 is the crankshaft structure schematic diagram of the embodiment of the invention one.
Fig. 2 is the side view of Fig. 1.
Fig. 3 is the detection error analysis schematic diagram of prior art.
Fig. 4 is embodiment one processing, detects schematic diagram.
Fig. 5 is the end view of reference block among Fig. 4.
Fig. 6 is the final detection schematic diagram of embodiment one.
Fig. 7 is the crankshaft structure schematic diagram of the embodiment of the invention two.
Fig. 8 is the side view of Fig. 7.
Fig. 9 is embodiment two processing, detects schematic diagram.
Figure 10 is the end view of reference block among Fig. 9.
Figure 11 is the final detection schematic diagram of embodiment two.
The specific embodiment
The bent axle to be processed of present embodiment has the first crank throw axle journal 2 and the second crank throw axle journal 3 that have eccentric O1, O2 with respect to trunnion 1 center of circle O respectively as depicted in figs. 1 and 2, is connected by scapulet 4 respectively between each crank throw axle journal and the trunnion.The keyway of symmetry 0.045 is processed according to the following steps and is detected on the trunnion 1:
The first step, is as shown in Figure 5 made two contour reference blocks 5 that upper and lower faces M, N are parallel.
Second step, on an end face of two reference blocks 5, process centre bore O1, O, the O2 of spacing A and line of centres consistent respectively perpendicular to upper and lower surface M, N with trunnion and crank throw distance between journal centers; Above spacing Deviation Control is in 0.02mm.Facts have proved: the total length with bent axle is that 2500mm, the long 250mm of crank throw are example, if the deviation of centre bore distance is 0.02mm, the crank throw axis is exactly 0.002mm with respect to the theoretical value of the depth of parallelism of main shaft, can reach very high precision.The deviation of the centre bore distance of processing two reference blocks will reach the requirement of 0.02mm than directly relatively easy at crankshaft two end making centre bore separately.
The 3rd the step, respectively reserve lengthening section 6 (being commonly called as the technology lug) at crankshaft two end to be processed, its diameter d 0 should be slightly less than adjacent axle head diameter, process the axle head location counterbore that internal diameter and technology lug diameter d 0 match respectively in the other end of two reference blocks 5, and by platform 7 location, the technology lug at two ends is inserted respectively in the axle head location counterbore of two reference blocks 5, and spot welding fixedly secures at crankshaft two end to be processed (referring to Fig. 4) two reference blocks respectively; Prevent from when noting welding to be out of shape to walk about, guarantee that the N plane that welds back two reference blocks is on the same plane, non-warping.
The 4th the step, on the lathe respectively with top each respective central holes of withstanding on the reference block of two ends, successively car go out to reserve the trunnion of surplus and two place's crank throw axle journals (the two reference blocks processing of can be directly when rough turn clamping crankshaft two end to be processed behind the assembly welding with chuck, during finish turning again the top centre bore process); The top centre bore grinds satisfactory trunnion and two place's crank throw axle journals on grinding machine again, and the processing of attention mill preface is counterweight routinely.
The 5th step, successively M and the N face with the two ends reference block is benchmark on Digit Control Machine Tool, two keyways (referring to Fig. 4) on the centering machining spindle neck.
The 6th step, be detection reference with the upper and lower plane of the reference block at two ends, by the angle square 8 that relies on trunnion 1 with use outside micrometer, measurement A1, A2 draw the symmetry of keyway for the crank throw journal centre and the trunnion line of centres.
The 7th step, detect qualified after, the lengthening section 6 and the reference block 5 of excision crankshaft two end.
The bent axle to be processed of present embodiment as shown in Figure 7 and Figure 8, only have the crank throw axle journal 2 that has eccentric O2 with respect to trunnion 1 center of circle O, its processing detects step and embodiment one roughly the same, owing to having only place's crank throw axle journal, therefore technical process is comparatively simple, does not give unnecessary details in addition.
In addition to the implementation, the present invention can also have other embodiments.For example, for large-scale bent axle, the location structure of axle head and reference block also can adopt various ways such as key joint, cottered joint, Desing of Interference Joint.One of embodiment provides and adopts easy reliable again welding manner.All employings are equal to the technical scheme of replacement or equivalent transformation formation, all drop on the protection domain of requirement of the present invention.