SU660790A1 - Method of cutting blanks, particularly, round ones - Google Patents

Description

The invention relates to the field of machine tools, in particular to methods for cutting blanks. There are known methods for cutting a blank, preferably round, with two saw blades rotating in opposite directions and located in one plane opposite to the blank. The workpiece is incised in such a way that one disk intersects its axis, the other one reaches the axis H. The disadvantage of these methods is their low productivity. In order to increase productivity, the workpiece after the incision is turned around its axis by an angle a (2R-a) - (a + bl2 4 2agoso5 gCa-bKk-a where R is the radius of the cutting disc, c is the minimum allowable gap between the discs at the end of processing, and the amount of movement of the disk beyond the axis of rotation of the workpiece .. The drawing shows a schematic diagram of the cutting method. The workpiece 1 is fixed in the rotation and clamping device of the machine. The cutting discs 2 and 3 are mounted on opposite sides of the workpiece at a right angle to its axis. opposite directions with speeds corresponding to ODg. The opposite direction of rotation of the discs is necessary to ensure that the billet is pressed by the cutting forces to the clamping device supports (with the same direction of rotation, the cutting forces will tend to rotate the billet around its axis.) The linear movement in the feed direction, respectively, with feeds S and S, are reported to the disks until the cutting surface of the disk 2 crosses the axis of the workpiece and takes a position at which its transition beyond the axis of the workpiece amounts to a. The resulting difference in the length of the cut between the discs can be provided in different ways, for example, feed 3 is set to more than $ 2 or the cutting disc 2 starts cutting earlier than disk 3, which is possible when using discs of different diameters. Taking into account the possible beating of the disc, rigidity and accuracy of the equipment and other technological processing conditions, the minimum is 3

6

The gap g between the discs 2 i.

3r, in which there is no contact between their cutting surfaces at the end of the working stroke in the feed direction, can vary between 3 and 8 mm. At the end of the cycle in question, an uncut area remains on the workpiece (shaded in the drawing). For complete cutting of the workpiece, it is turned around the axis O with a feed of 5 ,. at an angle of 4) so that point C of the uncut area moves to point B of contact with the cutting surface of the cutting disc 2 And the disk 3 cuts a part of the ACED section, the rest falls to the share of disk 2, Since only half of the active surface section is involved in the cutting during turning disks as compared to the cycle, when they move towards each other, the SJ feed can be significantly (2-2.5 times higher)

compared to feeds S and Sg.

Determine the angle f sufficient to fully unload the workpiece, depending on the radius R saw

In the coordinate system of the HOU, the equation for the circumference of the cutting-disk 2 is:

, 2 ..

x- (.

(О The trajectory of moving a point when rotating the workpiece has the form of a circle with a radius (a + b) and is antically represented as (c (-if). The joint solution of equations (2) gives the coordinates of point B - ((2Н-01 2 (Ra ) Since X takes a negative value, we take its modulus and make the angle Z / 2. Then the angle f 2arcco9f. - Haifa. (RQ Consider a number of specific examples. The commonly used standard cut dasks have a radius of 300-700 mm. We take the minimum distance by mekdau discs at the end of the cutting ... 10 mm. Then you need the required angle f in shape. (4) give the values data in table 1-2.,

Table 1

Values of angles f, hail, with a cutting disc radius of 300 mm

Claims (1)

Table 2 Angles with a 700 mm cutting disc radius Analysis of the calculated data shows that the influence of the radius R of the cutting disc on the angle P is not significant (compare the corresponding data in Table 1-2). When the value of xa is close to the value of в, the angles are relatively large (about 120 °). When the inequality is fulfilled, the angle f decreases and becomes smaller, the larger the ratio a / c. This should be borne in mind, and in carrying out the process, in order to increase productivity, the condition a – 1e should be fulfilled. The specific value of a is chosen from the condition of ensuring the maximum productivity of the process. The evaluation is carried out by comparing the machine time for moving by an amount a and a circular feed per angle. The method makes it possible to increase by 1.6-1.8 times the productivity of cutting large-sized workpieces, especially from difficult-to-work materials. This will make it possible to reduce the park of metal-cutting equipment and the area of the procurement shops of metal-working plants. The invention of the method of cutting blanks, mainly round, with two saw blades rotating in opposite directions and located in the same plane opposite the blank, in which the blank is cut in such a way that one disc intersects its axis, and the other does not reach the axis, characterized in that, in order to increase productivity, the workpiece after the incision is rotated around its axis by the angle aC2R-q1- (a + br I -2gsso5 2 (a- κКи-a | where R is the radius of the cutting disc, in - the minimum allowable gap between drives in to nce processing, and - the magnitude of the movement of the disk per axis of rotation of the workpiece. Sources of information taken into account in the examination 1. Voivode DK The main methods of automation in the forest industry, M., Goslesbumizdat, 1962, p.132, p, 45 .