SU1712286A1 - Method for piecemeal separation of non-magnetic conducting sheets from stack - Google Patents

Abstract

The invention relates to mechanical engineering and makes it possible to effectively separate the sheets from the foot due to the V simplicity and versatility of the selection of parameters that provide the necessary separating force. After capturing the top sheet, and lifting it together with the sheets coupled to it, eddy currents are induced by an alternating current electromagnet, when interacting the field of eddy currents with the electromagnet field, a repulsive force from the electromagnet arises; or by choosing a frequency in accordance with the condition — magnetic constant: y — electrical conductivity of the sheet material: h — its thickness, for a given penetration depth of the electromagnetic field, 2h. either by choosing the distance from the electromagnet to the electromagnetic screen, which is used by the unworn part of the foot or the massive table cover made of nonmagnetic conductive material, at a given penetration depth of the electromagnetic field y 2h, in accordance with the condition d Vi7jr7iyTi For reducing the forces acting on the gripping mechanism the separation of thick elastic sheets that exceed the size of the device, the electromagnet is placed on the edge of the sheet. To reduce electricity consumption, an electromagnet is switched on when lifting at least two sheets at a signal from. eddy current sheet counter, for which it is possible to use the same electromagnet. 1 fig. H: square 1 The invention relates to mechanical engineering, in particular to the processing technology of the Sheet material, and can be used in automatic processing lines of non-magnetic conductive sheets, for example, during their stamping. Methods are known for single-piece separation of sheets from the foot, which consist in simultaneously acting on the top sheet of the foot of the blanks and the alternating magnetic field of the magnetic field of the electromagnets and the permanent magnetic field of the permanent magnets coupled to it, and this joint effect causes the sheets to vibrate, contributing to their separation. There is a known method of separating a given number of sheets from the foot, which consists in capturing the top of the sheet with a magnetic chip and simultaneously affecting the sheets of the lateral magnetic field of the gripper. with the subsequent separation of a given number of sheets from the foot. The known methods are intended for separating magnetic sheets and do not allow nonmagnetic conductive sheets to be separated from the foot. N0 W About PvH7!>%

Description

The closest to the present invention is the method of single-piece separation of sheets from non-magnetic conductive material, which consists in capturing the top sheet using a separating suction, lifting the top sheet together with the sheets linked to it and separating the top sheet by creating its deflection when placing on the sheet edge load.

The disadvantage of the prototype method is the difficulty in selecting the length of the rod and the mass of the load to reliably separate the top sheet that. besides, does not allow to automate the process. In addition, when placing a load, local sheet deformation may occur.

The aim of the invention is to improve the efficiency of the method due to the simplicity and versatility of the selection of parameters that provide the necessary separation force.

This goal is achieved by that in the method of single-part separation of sheets from a non-magnetic material, including the seizure of the top sheet, its lifting together with the sheets linked to it and their separation from the top sheet, after lifting the coupled sheets, eddy currents in them are induced by an alternating current electromagnet The top sheet is produced by repulsive forces arising from the interaction of the field of eddy currents with the current field of the electromagnet, while either set the penetration depth of the electromagnetic field, not exceeding the thickness of two sheets, and ybirayut electromagnet current frequency in accordance with the condition 1

 f

where // is about the magnetic constant;

y — specific electrical conductivity of the sheet material;

h is the sheet thickness.

or set the penetration depth of the electromagnetic field greater than the thickness of the two sheets, and choose the distance from the electromagnet to the electromagnetic shield, which is the stationary part of the foot or the table cover from the nonmagnetic conductive mat in the series according to condition

Thus, a reliable non-deforming separation of sheets from a nonmagnetic conductive material with the possibility of automatic adjustment by parameters.

providing the necessary separating force is solved alternatively: either by choosing the current frequency of the electromagnet, which induces eddy currents in the sheets at a given depth of penetration

an electromagnetic field not exceeding the thickness of two sheets, depending on the thickness and electrical conductivity of the sheet (y), or the choice of the distance between the electromagnet and the unsaturated part of the foot, shielding its field (the screen can also be a massive table cover made of nonmagnetic conductive material ) for a given depth of penetration of the electromagnetic field exceeding the thickness

two sheets, depending on the frequency and y.

Indicated alternative signs

are technical equivalents so

as. differing in form (according to the choice of the parameters f or d). they coincide in function (ensuring the concentration of the floor in the linked sheets), as well as in the result achieved (obtaining a certain amount of eddy currents and, accordingly, the necessary separating force).

The ability to provide the necessary separating force (repulsive force) depending on the parameters of the sheets and the floor of the electromagnet makes it possible to automate the separation process, which is an additional advantage of the method in comparison with the prototype. Another advantage is the creation of a distributed separation force over the entire sheet volume, which excludes its deformation.

In order to reduce strength. acting on the gripping mechanism in the separation of thick elastic sheets that exceed the size of the device, the electromagnet is placed on the edge of the sheet.

In order to reduce electricity consumption, the electromagnet is switched on when lifting at least two sheets at a signal from

sheet counter (for example, eddy current probe).

When separating thin poorly conducting sheets, an electromagnet is used as an eddy current sensor (serving

For separating sheets).

The significance of the differences of the proposed solution is based on the following.

It is known that the interaction of the field of eddy currents induced in the conductive sheets. with the field of tsk electromagnet, they will be repulsed from the electromagnet. In this case, according to a known pattern, the repulsion of the coupled part of the foot from the electromagnet takes place.

However, there is no technical solution based on the fact that at the same time with such repulsion the top sheet is held by means of gripping, while ensuring reliable separation is provided by choosing the frequency depending on the parameters of the material being divided or choosing the required distance from the electromagnet to the screen for a given penetration depth of the electromagnetic field. .

Thus, we can conclude that a new set of features has been proposed.

The drawing shows a device that implements the method.

Example 1. In the device shown schematically in the drawing, the upper sheet 2 was taken from the stack of dural sheets by a vacuum grip 1, lifted together with the coupled sheets, 3, the electromagnet was switched on 4. the depth of penetration of the field was set equal to the thickness of two sheets, the current frequency chose the outcome of the CONDITIONS

ohm

L 210 m, from where f 690Hz.

Example 2. The methods of the method are the same, but. with the choice of the distance d from the electromagnet to the fixed part of the foot. At a given depth of penetration, the floor is greater than 2h. In accordance with the condition of the GNR (50Hz .015M. (At Hz .007 m,

Example 3: Same as in Example 2, but with a small thickness of the underside of the foot and concentration of the floor by shielding the cover of table 7 with a nonmagnetic conductive material (duralumin).

In this case, d is the distance to the surface of the table (calculated in the same way as in Example 2).

Technical and economic advantages 5 of the claimed method are compared with the prototype as follows;

- simplicity and versatility of the selection of parameters that ensure the reliability of the separation;

0 - the ability to automate the process;

- exclusion of local sheet deformation due to creation of a distributed repulsive force,

Claims (1)

5 claims The method of piece separation sheets of non-magnetic conductive material from the foot, consisting in. that capture the top sheet, raise it together The sheets are coupled to it and separated from the topsheet, which is characterized by the fact that, in order to increase the separation of the bonded sheets by ensuring optimal distributed force, the number of raised sheets is counted and, if n 1, they act on the raised sheets by electromagnetic field of alternating current, while setting the depth of penetration of the electromagnetic field of alternating current, equal to the thickness of two sheets and set the frequency of the alternating current supply in accordance with dependence 1 g g , // about the magnetic constant; Where y — specific electrical conductivity of the sheet material; h is the sheet thickness.