SU1166972A1 - Method of working articles in loose or liquid abrasive media - Google Patents

Description

The invention relates to the automation of technological processes, for example, in mechanical engineering, where the cleaning of products from contamination, scale, removal of burrs, grinding, polishing, etc.

. The closest to the invention is a method of processing products in various technological environments, which consists in the fact that the products are moved along with the technological medium along spiral trays of a vertically arranged cylindrical shell, giving it torsional vibrations. After processing, the unloading of products produced by changing the direction of oscillation of the shell U.

The disadvantages of this method are limited technological capabilities and low productivity. The method is used mainly for processing small items in small batches, which is caused by the low speed of vibratory movements due to the limited noise characteristics of frequency and amplitude of oscillations. Part of the unproductive loss of time when using this method also accounts for the unloading of products after the end of their processing. In addition, the inadequacies include the inability to control the processing of each product separately while managing the processing of all products.

The purpose of the invention is the expansion of the technological capabilities of the process by controlling the processing of each product separately with the simultaneous processing of all products.

This goal is achieved by the fact that according to the method of processing products in bulk or liquid abrasive media, in which they are moved along the helical surface of the drum, they change the speed of rotation and the angle of inclination of the drum, which are calculated by the formulas:

GT ¹ dos, (with _g -1 -ml-L P.

| Ch, ₇

where η - the number of revolutions of the drum;

§ - acceleration of gravity;

K - the radius of the drum;

c, is the largest size of the product

along the tray;

c ₂ , is the size of the product across the spiral tray;

d - the gap between the wall of the tray · and the product;

4, - wall thickness of the spiral tray;

P - the number of products issued at the steady state orientation;

ψ is the angle that determines the position of the center of mass of the product in absolute motion;

- the angle that determines the position of the products;

¢ 8 about ₂ ~ trigonometric function of the angle of elevation;

£ - coefficient taking into account the total efficiency of the elements of the working body, ensuring the movement of products in the receiver;

ψ is the angle of inclination of the drum to the horizontal plane;

οί ₂ - the elevation angle of the helix of the spiral trays;

- the value that takes into account the slope of the elementary section of the screw surface in contact with the product being moved.

FIG. 1 shows the movement of the process medium and products with the restriction of their issuance by changing the angle of the drum; in fig. 2 the implementation of the oscillations of movable products, section A-A in FIG. one; in fig. 3 - limiting the outweighing of the processed products by acting on them with a cutter, section BB in FIG. one; in Fig.4 the implementation of the continuous return d the initial position of the technological environment when issuing in the receiver processed products, node I in Fig, 1.

The method consists in that the process medium 1 and the product 2 are loaded into the drum 3 through the hatch 4. The products are processed by rotating the drum 3 using the actuator 5 around an inclined axis 6. The movement of the processed products 2 from the spiral trays 7 is limited by changing the inclination of the drum 3, for example, using a hydraulic cylinder 8 or by acting on them with a cutter 9.

1166972

During the rotation of the drum 3, the process medium 1 and the product 2 are moved by spiral trays 7 along the axis 6 towards the receiver 10. In view of the fact that the speed of the hydrodynamic flow of the technological medium 1 and the product 2 is not the same due to the different sizes and densities of the objects being moved the slippage of the technological environment 10 and products 2 is not only relative to the spiral trays 7, but relative to each other. This' causes continuous oscillatory movement of products, which are controlled by £ 5 by changing the speed of rotation of the drum 3 or by changing the angle of its inclination to the horizontal plane. The output of the processed products in the oriented position is also controlled by changing the speed of rotation of the drum or changing the angle of its inclination in the horizontal plane. At the same time, as the angle of inclination of the drum to the horizon increases, the speed of its rotation decreases, and with a decrease it increases, observing the condition that the centrifugal forces acting on the objects of treatment always were

less gravity:

, (t - the mass of the processed product;

K and C - the radius of the drum and its angular velocity, respectively; § acceleration of gravity).

According to this method, the oscillations of the particles of the technological environment “of the processed products are created not only by the torsional vibrations of the drum, but also by its rotation around 40 inclined axes with which these oscillations can be combined. This allows you to change the amplitude and trajectory of oscillations of particles of the technological environment and the processed products in a wide 45 ranges, including products of large sizes; Practically, observing the conditions for moving the products, rotating the drum around an inclined axis with its diameter within one-50 meters can handle products with a length of up to 300 mm with their cross-section up to 160 mm. In this case, the amplitude of oscillations of the largest products can be changed within the limits of their length 55, since for each revolution of the drum, the product at the contact boundary with its surface is initially carried away by friction and then slips (Fig. 2).

By changing the range of speeds and the angle of inclination of the drum, it is possible to vary the modes of processing products in various combinations (for example, starting with tumbling). The processing time with this method is reduced not only by eliminating discrete actions, but also by changing the trajectories and amplitudes of oscillations of products over a wide range. (When the drum rotates around an inclined axis, along with the oscillations of the products associated ⁴ with a change in the sign of the friction coefficient, excite their vibrations associated with the geometry of the spiral trays', since their points of contact are located on different radii.

It also contributes to the uniform processing of products over the entire surface).

Thus, the expansion of technological capabilities and an increase in the productivity of the process is achieved not only by working on a continuous cycle, but also by rotating the drum around an inclined axis, at which a significant increase in the amplitude of oscillations of both combined and individual products is possible. This method allows you to automate the control of processed products with the implementation of their return to rework without interrupting the cycle, for example, a signal from the control sensor to turn on the slam-shut cylinder.

Theoretically, the influence and estimation of the main parameters of the process can be explained by the equation obtained as a result of the joint solution of the system of equations describing the movement of a single product to the interface with the drum:

.. ‘/ 4ί„ £ θ05 0 <!. 2.

£ οο <3 ⁷ οί. ₂ οο5ψ, εο5ν 4 £ _п ^ соС2 ((ω \ ²

Xoz [C, 1? I.

where ψ is the angle that determines the position of the center of mass of the product in the absolute. lute motion;

£ ^. - the limiting value of the friction coefficient achieved by the product at the maximum points 1166972

foot elevation around an inclined axis;

оС ₂ - the elevation angle of the helix of the spiral trays;

ψ ₁ - the angle of the drum to the burn. vertical plane; r and K - the amplitude and frequency of torsional vibrations of the drum.

By the presence in the equation of the right side, it can be judged that, along with the oscillations of individual products associated with a change in the sign of the friction coefficient, oscillations will occur associated with the geometry of the spiral trays. '= (y'4 8co5 (k £ -6- £ g.)}

2.P,

to ^7- _{p with}

2P,

δ =

ού

sz cos £

R,

· -

£ οο5ψ, so5 ^g u _g sod ψ ' ¹

Ksob ^g (and,

5ΐ · ΥΊ £ 2 О When ωην 2.0 _n so5о0 _г й? to ν to 1

2ί _η ί and

AGS £ ^ —2 "О1гссо5-) | (- (-, suction cup

ten

15

20

25

thirty

ags

, βΐη (L, 4 6ΪΠ.

^AGS SO5 ψ, SO5 2.

ОЬ ^ П-НаУР ^ 1. ³³

N _th = <3ΐηοί. ₂ (βΐποί ₂ -ί £ (υ, δίηψ <).

The phase shift forced oscillations of ⁴⁰ products in spiral trays is

ε "-ε, + ε."

* * ¹ 2?

45

and the oscillations of the friction force are shifted relative to the oscillations of the cylindrical shell by an amount

1G

ε, = ε.ν

Own oscillations of products in. spiral trays are damped only under the condition ω <^ 2κ, which is equal to the strength “· but to the condition that there is no“ reverse ”movement of the spiral trays ω <κν.

If ko: “ω equitably ω = 0;

0,

then at 21 (2

4 | to ³ Кe0

28? „Cr8 £ _g

can

6

five

take place when -? oo; 5% o ", and at ² 2 K - --—---— p - * 0 wasps. 2 ^ £ _ц со5 (V. ₂ ^с г "n to ³ Ko £ Condition 2k & ^ - ~ - satisfied

with a sufficiently large value of the friction coefficient. In this case, the influence of the geometry of spiral trays Η ₀ on forced oscillations of products can be neglected.

When the values of P _with? = 0 there may be a case of resonance (К = Р _{С <} ), when? - '",. In other cases, only a slight increase in amplitude occurs. The maximum accelerations of products can reach the limiting values at K- »oo, when the amplitude of forced oscillations tends to zero inversely proportional to K ² ,

Automatic self-synchronization between the oscillation frequencies of the technological environment and the products resting in it contributes to the orientation of the latter in a well-defined position. The speed of this process increases with the simplification of the shape of products and can be determined from the conditions

90C., (Cr.4-44 b,) P

ΐ · £ <* · ζ '£ ’

where η - the number of revolutions of the drum;

P _e - the number of products oriented for a given time interval ^

c, is the largest size of the product along the spiral tray

'· (For products like cylinders with, = 1 for 1> b and c, = b for 1 <b);

с ₂ - product size across the spiral tray (for products of the cylinder type with ₂ = b at 1? ά and with ₂ = 1 at 1 ^ 6);

d - the gap between the wall of the tray and the product;

& 1 is the wall thickness of the spiral tray;

x ^ is an indicator that takes into account the number of items accounted for!

7

eleven

per unit area of spiral trays;

ί (g) function defining a curve that limits the area of contact of disordered products with the orienting surface;

Ζφ ζ _χ - coordinates that define the initial and final boundaries of the contact area with the surface of the spiral trays along

axis of rotation of the drum;

I

ζ - the number of screw visits;

П - the number of products issued at the steady state orientation mode;

2 - coefficient taking into account

total efficiency of working elements ·

What is the authority that ensures the transfer of products to the receiver?

> 6972 8

Example. To test the feasibility of implementing the proposed method and assess its effectiveness as compared with the known devices (Fig. 1), we checked the possibility of removing contaminants and burrs up to 1 mm in size.

10 Results are presented in the table. .

The proposed method of processing products in bulk - or liquid media provides the ability to control the processing of individual products while managing the processing of all products with the movement of each product along well-defined paths.

Options

Way

Famous

Proposed

'Sizes of products, mm

diameter

length

Drum diameter with spiral trays, mm

Mass of loaded products, kg Minimum removal time of pollution in a soap solution with various treatment modes, min. Minimum removal time of burrs up to 1 mm in size with various treatment modes, min. Pace rate of the oriented feed of processed products from the processing medium, scht / min

Replaceable capacity, pcs / min

ten . 20 thirty' ten 20 thirty sixteen 35 60 sixteen 35 60 630 630 630 630 630 630 thirty zo thirty thirty thirty thirty 85 108 115 five· 7 12 78 95 108 12 > 12 25 150 120 95 480 400 340 750 600 475 3360 2800 2380

1166972

Loading

FIG. one

FIG. 2

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FIG. four

Claims (1)

THE METHOD FOR PROCESSING PRODUCTS IN BULK OR LIQUID ABRASIVE MEDIA in which they are moved along the helical surface of the drum, characterized in that, with the aim of expanding technological capabilities, they change the speed of rotation and angle of inclination of the drum, which are calculated using the formulas: 90C, (C ₂ + & + MP ·. where η - the number of revolutions of the drum; β is the acceleration of gravity; K - the radius of the drum; c, is the largest size of the product along the tray; Δ B P 7 -ί £ οί ₂ <V _g ί "' product size across the spiral tray; the gap between the wall of the tray and the product; wall thickness of the spiral tray; the number of products issued at steady state orientation; the angle that determines the position of the center of mass of the product in absolute motion; the angle that determines the position of the products; trigonometric lift angle function; coefficient taking into account the total efficiency of the elements of the working body, ensuring the movement of products in the receiver; the angle of the drum to the horizontal plane; helix angle of elevation: spiral trays; a value that takes into account the slope of the elementary section of the screw surface in contact with the product being moved. > one . eleven