The memory of automobile obsolete crankshaft magnetic detects special-purpose signal pickup assembly
Technical field
What the present invention relates to is a kind of pick-up unit of automobile technical field, specifically, is that a kind of automobile obsolete crankshaft magnetic memory detects special-purpose signal pickup assembly.
Background technology
Automobile engine crankshaft, owing to born very big alternate load at work, fatigue failure is one of its main form of invalidation.Therefore, the retired part of this class is before making again, at first need it is carried out remanent fatigue life test and appraisal, determine whether the remanent fatigue life of this part is enough to keep next life cycle, and estimate this part as important indicator and whether have the value of making again.Because also the military service history of imprecise understanding automobile obsolete crankshaft is difficult to directly count its remanent fatigue life.Though the magnetic powder inspection technology can be carried out the macroscopic cracking check of bent axle, but, if certain bent axle does not detect macroscopic cracking as yet, but be in the fatigue damage later stage in germinating stage, this part is through after making again, whether can be enough to keep whole life its fatigue lifetime, just is difficult to make answered.Therefore, in actual production, the retired engine crankshaft of Zhi Zaoing is not carry out the remanent fatigue life test and appraisal more at present.If can set up an effective remanent fatigue life of vehicle retired crankshaft detection method of cover and a device, by directly retired part being tested and assessed, just can obtain its remanent fatigue life, thereby judge whether this part is worth making again, is highly significant for improving the reliability and the security that manufacture a product again.The ferromagnetic metal part is when processing and operation, owing to be subjected to load and terrestrial magnetic field acting in conjunction, directed and the irreversible reorientation of magnetic domain tissue that can have magnetostriction character in stress and distortion concentrated area, form the variation of maximum stray field Hp, promptly, the tangential component Hp in magnetic field (x) has maximal value, and normal component Hp (y) reindexing and have zero point.The irreversible change of this magnetic state not only can keep after operating load is eliminated, and also relevant with maximum effect stress, the position that microdefect or stress mutation " is remembered " in this magnetic state, promptly so-called magnetic memory effect.By mensuration to stray field magnetic memory parameter Hp, just can accurately infer the region of stress concentration and the degree of workpiece, thus the remanent fatigue life of assessment workpiece.Therefore, the stray field magnetic that how to obtain decommissioning crankshaft surface same position synchronously and is accurately remembered the normal component Hp (y) of parameter Hp and the detection signal of tangential component Hp (x), stress deformation situation to correct judgement decommissioning crankshaft surface dangerous position has crucial meaning thereby estimate its residual life.
Find by prior art documents, " development and the Preliminary Applications of railway special-purpose metal magnetic memory detector " (Chinese railway science that Yang Qiming delivers, 2005 01 phases) in the literary composition, introduced the development content and the major function of MTR1 sections road special-purpose metal magnetic memory detection device based on the ultimate principle of metal magnetic memory, pick-up unit is by main frame and detect dolly two parts and form.Develop the detection dolly at the design feature of rail, fixed a single probe on it, and vertical with detected.Steady when mobile when dolly along rail, can realize detection to rail.But this device once can only carry out normal direction or tangential detection separately, can not obtain the normal direction and the tangential magnetic memory detecting signal of surface of the work simultaneously, can not accomplish accurately and fast the evaluation of surface of the work stress mutation.
Summary of the invention
The objective of the invention is to overcome deficiency of the prior art, propose the memory of a kind of automobile obsolete crankshaft magnetic and detect special-purpose signal pickup assembly, make it can be synchronously and accurately obtain the normal component Hp (y) of stray field magnetic memory parameter Hp of decommissioning crankshaft surface same position and the detection signal of tangential component Hp (x).
The present invention is achieved by the following technical solutions, the present invention includes: roller, coupling bolt, normal stretch screw, normal probe, supporting base, level presses closer screw, removable probe base, tangentially press closer screw, tangential probe, roller links to each other with supporting base by coupling bolt, normal probe is located on the supporting base by normal stretch screw, tangential probe is by tangentially pressing closer screw retention on removable probe base, removable probe base, tangentially pressing closer screw and tangential probe does as a wholely to press closer screw by level and be located on the supporting base.
Described normal probe is Hall type magneto-dependent sensor probe, and cylindrical, diameter is 6 millimeters, and range is ± 2000A/m.
Described tangential probe is Hall type magneto-dependent sensor probe, and cylindrical, diameter is 6 millimeters, and range is ± 2000A/m.
When detecting the bent axle surface, should make two rollers place tested bent axle surface, adjust two rollers and contact with the bent axle surface simultaneously, so just guaranteed that normal direction center probe line overlaps with the bent axle normal.Unclamp normal stretch screw, adjust normal probe to suitable with the bent axle surface spacing, tighten this normal stretch screw again, this moment, the position of normal probe was just fixed.Then,, can carry out level and vertical direction adjusting to tangential probe by level being pressed closer screw and tangentially pressing closer loosening, tighten of screw, tangent until probe front end face and bent axle surface.Two probes are connected with the magnetic memory detector device by same single data transmission line.At this moment, turning crankshaft then can be gathered tangential component and the normal component signal Synchronization of the stray field magnetic memory parameter Hp of bent axle surface same position, and its normal direction and tangential signal differ for four/one-period.
The present invention can realize synchronously and accurately tangential component and the normal component signal of the stray field magnetic memory parameter Hp of decommissioning crankshaft surface same position be gathered, compare with single probe manual inspection mode, use this magnetic memory signal to gather structure and can will shorten to original half detection time, and, improved the efficient and the accuracy of decommissioning crankshaft remanent fatigue life test and appraisal because synchronization gain is tangential and the magnetic memory of normal component detects data.Signal acquiring system involved in the present invention has adopted two sonde configurations, is applicable to the detection of bent axle, can be simultaneously to the bent axle surface tangential and normal direction magnetic memory signal gather, thereby stress mutation quick, exact evaluation bent axle surface.
Description of drawings
Fig. 1 structural representation of the present invention
Embodiment
As shown in Figure 1, the present invention includes: roller 1, coupling bolt 2, normal stretch screw 3, normal probe 4, supporting base 5, level presses closer screw 6, removable probe base 7, tangentially press closer screw 8, tangential probe 9, roller 1 links to each other with supporting base 5 by coupling bolt 2, normal probe 4 is located on the supporting base 5 by normal stretch screw 3, tangential probe 9 is fixed on the removable probe base 7 removable probe base 7 by tangentially pressing closer screw 8, tangentially pressing closer screw 8 and tangential probe 9 does as a wholely to press closer screw 6 by level and be located on the supporting base 5.
Described normal probe 4 is Hall type magneto-dependent sensor probe, and cylindrical, diameter is 6 millimeters, and range is ± 2000A/m.
Described tangential probe 9 is Hall type magneto-dependent sensor probe, and cylindrical, diameter is 6 millimeters, and range is ± 2000A/m.