The workpiece proper circle measures instrument
The utility model belongs to a kind of workpiece proper circle and measures instrument.
At present, judge whether proper circle of cylindrical work, generally adopt the external pelivimetry pawl of vernier caliper, the diameter that measures on the different directions can judge.But, utilize vernier caliper to judge and occur the mistake survey sometimes, for example, when a certain xsect is that its outer surface of cylindrical work piece is shaped as isometrical abnormal shape, perhaps there is concavo-convex phenomenon in regional area, and the diameter that vernier caliper is measured all is consistent, and it can not measure the diameter situation at the tiny position of cylindrical profile face of cylindrical work, is the conclusion of proper circle and make it.
[summary of the invention]
For overcoming the problems referred to above that prior art exists, the utility model aims to provide a kind of workpiece proper circle and measures instrument, utilizes this measurement instrument can measure the concavo-convex situation of each point on its cylindrical profile face of cylindrical work easily, is the conclusion of proper circle and make it.
For achieving the above object, the utility model has adopted following technical scheme: this workpiece proper circle measures instrument, comprise that one has the scale of sounding rod, it is characterized in that: described scale is arranged on the end face of a measurement bay, the bottom of measurement bay has an isosceles trapezoid opening, described sounding rod passes measurement bay along stretching under the axis of symmetry of isosceles trapezoid opening, and the measuring junction of sounding rod is positioned at the top of isosceles trapezoid opening.
Beneficial effect: compared with prior art, the utility model utilizes one to have the scale of sounding rod and the combined structural member of a measurement bay, opening by the isosceles trapezoid shape on the measurement bay is admitted tested cylindrical work, finish measurement by the measuring junction of scale sounding rod to workpiece, during operation, continuous rotation along with workpiece, the measuring junction of scale can outer surface to cylindrical work on, each zone or tiny position are measured, thereby help operating personnel to make the whether conclusion of proper circle of this workpiece.
[description of drawings]
Fig. 1 is the broken section structural representation of an embodiment of the utility model;
Among the figure: measurement bay 1, scale 2, sounding rod 3, measuring junction 31, dial plate 4, gage beam 5, card survey face 51, isosceles trapezoid opening 6.
Referring to Fig. 1.Measurement bay 1 is the crotch shape, and both sides are gage beam 5, all has a card survey face 51 on each gage beam 5.Form an isosceles trapezoid opening 6 in the middle of two gage beams 5, it is used to admit the tested cylindrical work of different-diameter.The end face of measurement bay 1 is horizontal, and scale 2 is arranged on this end face, and the sounding rod 3 of scale 2 extends through horizontal measurement bay 1 downwards.Measuring junction 31 is positioned on the axis of symmetry of isosceles trapezoid, on the top of isosceles trapezoid opening 6.Measuring junction 31 and two card survey faces 51 are on the circular arc with peripheral contacted 2 of workpiece.
During use, two card survey face 51 and measured workpiece surfaces contact and rotate (otherwise also can) along surface of the work, because the contact point of measuring junction 31 and two card survey face 51 and measured workpiece coexists on the proper circle, therefore, dial plate 4 pointers then illustrate the non-proper circle of this cylindrical work if any beating, and, can check out the round runout error of measured workpiece easily according to pointer displayed numerical value on the dial plate 4.