SU755523A1 - Finishing method - Google Patents

Description

The invention relates to the field of mechanical processing of metals, in particular to methods of grinding and processing metals using grinding, polishing or finishing machines and devices, and can be used for final finishing processing of products such as rotating bodies, for example, hydraulic cylinder rods after coating in the engineering industry.

There is a method of finishing processing, according to which the part is fed into the treatment area and pressed against the grinding belt with a constant force. The tape performs a reciprocating rotational movement around an axis perpendicular to the plane of the table, and the part moves the feed. This provides an improved quality of the surface-20 parts due to the additional imposition of processing strokes due to predetermined movements of the sanding belt [1].

The disadvantage of this method

is the unevenness of metal removal when processing parts such as rotation bodies with coatings of small thickness, as due to the variable contact quantity at constant 30

ten

15

25

belt tension the average pressure in the treatment area are variable. This leads to fluctuations in roughness parameters. On different parts of the surface to be treated? which degrades the quality of machining the part and forces, in order to achieve a given surface quality, to reduce the supply of parts and, consequently, to reduce productivity.

The aim of the present invention is to improve the quality of the machined parts and increase the productivity of the process.

This goal is achieved by the fact that in the proposed method of finishing treatment an additional variable load is applied to the grinding belt, varying periodically depending on the angle of rotation of the tool, and is selected from the condition of maintaining the constancy of the average pressure in the zone of contact of the tool with the part.

The use of the proposed method of finishing treatment in comparison with the existing ones ensures the formation of a roughness on the surface being treated with a smaller value of dispersion of its parameters by creating a constant contact pressure 755523

four

in the machining area for a given reciprocating rotation of the tool in a plane parallel to the axis of rotation of the part. This ensures uniform metal removal from the surface and allows parts to be machined at elevated conditions, for example, with feeds increased by up to 20%, which leads to an increase in the productivity of the process.

FIG. 1 shows a diagram of the proposed method of finishing processing; in fig. 2 is a view A of FIG. one.

In the implementation of the proposed method of processing parts 1 report rotation with speed, and grinding belt 2 - moving with speed ν _Λ . Tape 2 or dyadal 1 performs a feed movement of 5 ^. In addition, the tape sets the reciprocating rotational movement 5d at an angle of 2 sec in a plane parallel to the axis of the part.

Tape 2 is brought into contact with part 1 and pressed against the part with force, which in position 1 of the tape (Fig. 1) is the value of P. In this case, a tension is created between the part and the belt!, And contact pressures develop in the contact zone, the plot of which is shown in FIG. 2

In position I of the tape, the area of contact of the tape with the part

where% is the contact width;

- contact length, equal in position I to the width of the tape 6 _D.

In this position, the average pressure in the contact zone will have the value

R _

With _P 1 P _{A T} 6.

In position II (III) of the tape, the average contact pressure

R

Ср2 η, · Κ ₂

where P is the force of pressing the tape to the part when it is rotated at an angle about;

the length of the contact zone in this position of the tape.

Because

„Рч, · С О 506

p = - "- *

cf2 η, · Wa

When machining parts, especially with thin metal coatings, elastic abrasive tools, it is important to create the conditions under which uniform removal of metal along the contact length is achieved. These conditions are ensured with equal average contact

ten

15

20

25

thirty

35

40

45

50

55

pressures at any position of the belt within the limits of its rotation by an angle of ± ± with constant tension яг, i.e. equal contact pressure conditions must be met

^ρ ορι ⁼ p ^P sc. ^{= CO} , ^P51 ·

From where Ru = -e.e. in order to maintain the constancy of the average pressure in the zone of the Tool’s contact with the part, when the belt is turned, it is necessary to attach to it a periodically changing additional load equal to

Ra = R.,

- ^P o =

-Η - p _

SO50S O

CO500

= Р „

sozos / 'o'' ^ϊ 9 ⁰⁶ '

Thus, the clamping of the tape to the workpiece with an additional, varying depending on the angle of rotation of the tool, variable force, which is established from the condition of maintaining the constancy of the average pressure in the contact zone, for example, equal to P ^ = P _{o .} provides a uniform removal of the metal over the entire surface being processed with the smallest value of dispersion of roughness parameters at any position of the tool within its turning angle! This improves the quality of the machined parts and allows you to increase their feed up to 20%, which causes an increase in the productivity of the finishing process.

Claims (1)

Claim The method of finishing processing abrasive tool, for example, elastic diamond tape; wherein the tool is pressed against the machined surface with a constant force and is given to it a reciprocating rotational movement at a certain angle in a plane parallel to the axis of rotation of the part with simultaneous rotations and feed of the tool and part, about In order to improve the quality of the machined parts and increase the productivity of the process, an additional variable force is applied to the tool from the condition that the average pressure is kept constant in the zone of contact of the instrument with detail depending on the angle of rotation of the tool.