SU1219256A1 - Method of compensating for shape irregularities of articles of non-circular section in turning - Google Patents

Description

"

The invention relates to machine tool CTpoeTtHH) and can be used in the finishing turning copy processing of pistons with a non-circular cross section.

The purpose of the invention is to improve the processing accuracy by introducing an angular and scale correction of the probe displacement relative to the copier.

FIG. 1 shows a device for implementing the proposed method, top view; in fig. 2 is a section A-A in FIG. 1; in fig. 3 is a section BB in FIG. 2; in fig. 4 shows a section B-B in FIG. 1 in FIG. 5 is a cross-section of the FIG. one; FIG. 6 is a section DD-D in FIG. one.

On the base 1, the spindle head 2 is movably mounted, carrying a copier 3 mounted on the spindle shank. A fixture 4 is mounted on the spindle flange to secure the piston 5. Parallel to the spindle head 2, the shaft 7 with levers 8 and 9 is rotated in the movable supports 6 and 9. On the lever 8 is executed on the circular guide 10, carrying the holder 11 with the sump 12 and nuts 13 and 14. To accommodate the holder shank; 11 a groove 15 is made in the lever 8. The lever 8 together with the probe 12 is elastically pressed into the copier 3 by the spring 16. On the lever 9 mounted rez 17. The housing device 4 for attaching the piston 5 is mounted with the possibility of adjusting the rotation sleeve 18, which is formed on the base projection 19 for the angular orientation of the piston. A wedge 20 is installed in the housing, mutually acting with the sleeve 18. Inside the sleeve 18 a ha 21 is placed with a hole under the clamping finger 22.

The method is carried out as follows.

On the device 4 install the piston 5, Turn on the rotation of the cylinder and, feeding the spindle head along the axis of the spindle, test the piston. At the same time, the tip of the tool is at point A, and the point Kasagsh of the probe and the copier is at point C. After finishing the machining, control the location of the given points on the piston, do not remove it from the spindle. If there is a deviation (i.e., distortion of the form goes beyond the great-grandfather's tolerance floor)

62

The nut 13 and the holder 11 together with the probe 12 are moved along the circular guide 10 by an angle determined by the calculation below.

After the movement of the holder 11 with the probe i2 is completed, it is fixed with a nut 13. After that, the angular position of the base lugs 19 of the sleeve 18 is adjusted. For this, the sleeve 18

wedge, turn to the required angle and wedge wedge 20. The calculation of the required displacement of the probe and the angle of rotation of the sleeve 18 relative to the body of the device

D.GTA fixing the workpiece is made on the basis of the following considerations. Changing the probe position results in a change in the copy scale. Denote the length of the theoretical radius vector proerdenal to the control: the point being checked is A., p, and the initially obtained value of the corresponding radius vector is A, Most of the engine pistons

internal combustion sh-1eut in cross section oval. At the same time, the search for the desired control is performed from the actual location of the major or minor axis of the oval on the treated

the piston.

In order for the radius vector length to correspond to A at the controlled i-th point, it is necessary to change the copying scale in accordance with

with a ratio of:

- A A

Mikes

mdks

- BUT; M, p

M:

BUT,

(one)

where a „.,

MM;

-maximum magnitude of the radius-vector of points of the surface of the piston (greater semi-axis of the oval) j

i-scale required

- the original copy scale used;

W., (AMSXXL ,;) is the required theoretical reduction in the length of the radius-vector of the controlled point in comparison with H1-HY with the major semi-axis of the oval;

Y; (A) - originally

obtained reduction of the length of the radius-vector of the controlled point compared to the large shaft semi-axis.

Relationship (1) reflects the fact that, taking into account systematic processing errors during copying, the amount of change (increment) in the length of the radius vector of the test point relative to the major axis of the oval is inversely proportional to the copying scale used (with the same change in the length of the corresponding copier points).

Dp calculating the required amount of movement of the probe 10 along a circular path, the following notation is introduced:

a is the distance from the axis of swing of the arms to the tip of the incisor ();

b is the distance between the axis of swing of the arms and the axis of rotation of the spindle (00.0);

c is the distance from the axis of swing of the levers to the point of contact - the probe and the copier to compensation (0 C),

c, is the distance from the axis of swing of the levers to the point of contact between the probe and the copier after compensation () j

R is the length of the radius vector of the piston surface drawn from the axis of rotation of the spindle and lying on the major axis of the oval (),

R is the length of the radius vector of the point of the surface of the copier, carried out by the rotation of the spindle and lying on the major axis of the oval (To C)

P is the angle between the straight line connecting the swing axis of the levers with the tip of the cutter and the straight line passing through the swing axis of the levers and the axis of rotation of the pinch at the moment the point of the piston surface is processed by the cutter, l on the major axis of the oval of its cross section;

S is the angle between the straight line connecting the swing axis of the levers and the point

U r

, -Ja-.6 -2a & eos {p-o..csu, (-1 V, n &} - ar, cos

219256

touching the probe with a copier and a straight line passing through the axis of swing of the levers and the axis of rotation of the spindle until compensation,

5 I

V is the angle between the straight line connecting the axis of swing of the levers and the point of contact of the probe with the cam and the straight line passing through the axis of swing of the lever

10 and the axis of the enemy spindle after compensation.

The magnitude of the copy scale is determined in a consistent manner.

15 From a triangle, for processing a point lying on the major axis ba.1a, () (0, С) 2 + (O.OO - - 2 (0, С) (0 Oj) -cos it, or RI с2 + B2 is 2c-b-coso (,, where d. ,, 20 is the angle between the straight line connecting the axis to the span with the point of contact of the copier and probe at the time of processing the point of the major axis of the oval and the right ().

25 When moving to a controlled point, the length of its radius-vector, drawn from the axis of rotation of the spindle, decreases by the value of X, then (X) 2 с2 + Ь2 - 2cbccs (o (30) (2), where AoC is the angle corresponding to the increment X (by the Ad value, the lever 8 with the probe rotates, and with it the lever 9 with the cutter).

35

40

45

From the triangle O, AO, (for processing a point lying on the major axis of the shaft)

R a + b - 2abcosp,

and for a controlled point, the magnitude of the radius vector of which is less than the major semiaxis by the value of y,

(R, - y) 2 a. + B - 2abcos (p. -Do1,)

(3)

From the triangle O, CO,

50

S in au ,. sin with

- RK

or

.RV

0 /, arcsin (-i). (four)

From expressions (2), (3), (4) we get:

S)

For positioning the probe at point C, the copy scale is determined by the ratio

, m.- ..

/; :

Y a & cosjp-QPCsinC s m Y) -arccos I

The value of C, can be determined from the triangle OVO

C, b + RH - ji

The scale of copying M is hereby determined by the formula:

M ...

In order for the compensation to lead to the required scale change, the probe is moved from the starting point (C) to such a point (B) so that the newly obtained copy scale corresponds to the relation (1).

GAME -

2

UG

Ratio

MTP X / YT Zi.

MI x7y, y

From the ratio obtained, you can determine the required angle

g

to ensure (required

theoretical differential).

Having determined the angle Os, one can determine the required value of the probe displacement by a circular guide using the formula:

.; A - y).,

However, this changes the angle ((- y) angular position

When moving the probe from point C to point B, the value of y is determined by the formula (for the same value X

(RK-)

,

portable profile relative to the base protrusions 19.

In addition, due to the inertia of the copying system, there is a delay in the movement of the tool relative to the probe. This results in an initial angular deviation of the H of the respective control points relative to the base lugs (copy lag).

To compensate for this error, the wedge 20 is released and I turn the sleeve 18 with the base elements 19 by angle 0, determined by the algebraic sum of the angle of the initial angle of deflection Y and the angle of the probe in the circular direction for compensation of 0 V + (s –y). After that, the sleeve 8 is fixed with a wedge 20. Moving the probe in a circular path around the axis of rotation of the copier allows, after compensation, not to change the position of the tool (not to adjust the tool).

The proposed method is applicable in the presence of several controlled points on the transverse profile of the piston. In this case, the compensation is made from the average value of the originally obtained deviations of the length and position of the radius vectors of the corresponding points.

fff k 8

lg

.

I

one

t

i

one

,four

FN9.1

n9fttijf

6-B

Fig.Z

Bb

/one,

AJ r-r

/ 8 21, 5 .13, yy

Editor S.Patrusheva

Compiled by V.Semenov Tehred M.Nad

Order 1191/16 Circulation 1001Subscription

VNIIPA USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, st. Project, 4

2.5

Proofreader S. Shekmar

Claims (1)

'METHOD FOR COMPENSATING ERRORS OF THE FORM OF PRODUCTS WITH A NON-CIRCULAR CROSS SECTION WHEN LATCHING, by copying synchronously rotating together with the product by means of a feeler gauge and a cutter of the lever system, the swing axis of which is parallel to the measurement and processing axes of the copier and the product axes; angular and large-scale correction by the displacement of the probe, characterized in that, in order to increase the accuracy of processing, after the trial processing, a linear deviation of the radius vector is determined, drawn to a controlled point of the product profile from its predetermined value, and the probe is displaced by rotating it around the axis of the copier, after which the part g is rotated relative to the copier by an angle equal to the sum of the angle between the controlled and preset positions of the radius vector and the angle of rotation of the probe around the axis copier. 9ШШ ^{,, П} OS ί 121