SU921677A1 - Method of measuring chip shrinkage - Google Patents

Description

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The invention relates to methods for measuring plastic deformations when cutting metals.

There are known methods for measuring chip shrinkage, in which the coefficient of shrinkage in a selected section of chip width in relation to the cutting path to the chip length is determined, for example, a method in which chip shrinkage ratio in relation to the cutting path to the chip length is determined. a groove on the outer surface and the L1 chip width measured along the centerline. .

However, this method does not measure chip shrinkage at any point of the cutting blade and cannot serve as a measure of plastic deformations, as it does not take into account the discrepancy during oblique cutting and relative rotation of the workpiece and the cutting path tool with the direction of plastic deformations, the direction of the chip length measurement with the direction of her shovel and elongation of chips due to the displacement of its elements along the cutting blade outside the cutting zone. As a result, the method gives low accuracy and limits the measurement range of chip shrinkage.

There is also known a method for measuring transverse shrinkage of a chip with respect to the thickness of the log to the depth of cut.

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But due to the large influence on the results of chip thickness measurements of its elemental structure, the accuracy of the method is low.

Closest to the proposed

IS is a method for measuring chip shrinkage, in which the coefficient of shrinkage in a selected area of chip width in relation to the cutting path to the chip length is determined, a feature

Claims (3)

20 of which consists in the fact that chips are obtained during the reaming of the samples, and the shrinkage ratio is determined by the ratio of the length of the sector to the length of the chips 39 ki. chips in different areas of the cutting blades. The disadvantage of this method is low, the accuracy of measurement of chip shrinkage. This is caused not only by the fact that the method does not take into account the discrepancy during oblique cutting and relative rotation of the workpiece and tool cutting path with the direction of plastic deformations, the directions for measuring the length of the chip and its runoff, as well as the elongation of the chip due to the displacement of its elements along the cutter; blades outside the cutting zone, but also due to the fact that the drill sample: the vanilla distorts the direction of the chip runoff and the relative cm value of its elements along the cutting le; VIA compared to continuous drilling: due to adavlivani metal at the edges of the chip and exclusion vzaimovli audio adjacent cutting blade along the length of the layers, resulting in varying chip lengths. The purpose of the invention is to improve the accuracy of shrinkage measurement during oblique cutting. The goal is achieved by the fact that the angle of rotation of the plane of greatest deformations is measured in the same area, the direction and angle of the chip run are determined, and the shrinkage ratio is calculated using the formula V J-Jl J .. L iros Tcosl where K is the chip shrinkage ratio j LQ - the path of relative motion, I cut; its blade, in the sample, mm; L is the length of the chip in the direction of its escape, mm; angle of inclination of the cutting blade, hail, - angle of ejection of chips, hail ,; J - angle of rotation of the plane of the greatest deformations., Deg. The drawing shows schematically an example of the implementation of the proposed method. The cutter 1 shows the cutting blade 2, chips The sample, the cutting surface 5, the width B of the chip 3, the section b of width 8 5 the direction of movement; and V of the cutter 1, the plane of the most deformations of their deformations R, the direction of the runout. chips 3, inclination angle A of the cutting blade 2, angle of rotation g of the plane of greatest deformations H, cutting angle 74 of the chips 3, relative path of movement LO of the cutting blade 2 in the sample, cutting path Lp, length L of the chips 3 in the direction of the offset. , the length of the LC chip 3, the normal N plane to the cutting blade 2, the initial position I and the final position II of the cutting blade 2. The cutter 15, having the direction of movement V, removes the chip C from the sample 3. The position of the cutting blade 2 of the cutter 1 relative to the direction of movement V characterized by the angle of inclination .Jv, the presence of which makes the cutting coaxial. When oblique cutting, deformation of sample 4 when chip 3 is removed does not occur in the normal plane N 5 and in the plane of greatest deformations (. As a result, when the cutting blade 2 moves from the initial position T to the final position If, chip 3 moves s running and. has a length L. At any angle of rotation of the plane of greatest deformations R, the formation of chips 3 occurs perpendicular to the surface of the cutting 5; therefore, in order to exclude the measurements of shrinkage of the chips 3 due to the influence of rotation H h, friction forces and other factors not related to strains during chip formation should be measured in LC length 3 of chip 3 in the normal N plane to the cutting blade. 2. Know the angle of the run. The Chip 3 dependence is easily obtained as a result of plastic deformations in the plane of greatest deformations R, therefore the cutting path Lp should also be measured in the plane R. With a known relative motion path LQ, given the inclination angle D of the cutting edge 2, measuring the angle of rotation vj. find the cutting path of I.-fs according to the formula 1. aC05L Tg (to as the width B of the chips 3 the angle of departure is not constant with the relative rotation of the sample 4 and the cutter 1 and TipH variable angle of inclination L along the cutting 2, such as when drilling, The shrinkage factor K should be determined on a narrow section b of the width B of the chips 3. Calculation according to the formula K - Lp / Lc. The method is implemented as follows: In the section B of the width of width B st (angle 3 measures the angle of rotation V of the plane of greatest deformations , for example in the direction of the shear strokes in the chip 3, on the image They do not fix the path of relative movement La and determine the cutting path Lp in the plane R. Then measure the length L of the chip 3 in the direction of the run Vc using a flexible wire and a ruler, determine the speed, for example, on the grooves on the cutter side of the chip 3. On the instrumental microscope, setting the sample with chips 3, measures the angle of escape also, for example, in strokes on the rift side of the chip 3. Calculate the chip shrinkage coefficient according to the formula LO cos Jv BC05TCS05 G and take it as a measure of chip shrinkage. A comparison of the proposed method with the known method showed its high TO Ignitude by 30%. In addition, the ability to measure chip shrinkage on small-sized specimens while removing short shavings saves metal. 9 7 The invention The method of measuring shrinkage of chips, which determines the coefficient of shrinkage in a selected area of chip width relative to the cutting path to the length of chip, characterized in that, in order to improve the accuracy of measuring shrinkage during oblique cutting, the angle is measured in the same area rotation of the plane of the greatest deformations, determine the direction and angle of the chip runoff and the shrinkage ratio is calculated by LOGOS L L cos VLCOS V where K is the chip shrinkage coefficient; LO is the path of the relative movement of the cutting blade in the sample, mm L is the length of the chip in the direction of its cutting, mm; ot is the angle of inclination of the cutting blade, v is the angle of ejection of chips, hail; G - the angle of rotation of the plane of the greatest deformations, deg. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 276692, cl. B 23 B 39/00, I960.