SU1212651A1 - Method of setting sheet work into nip of gripping jaws of pull-over machine - Google Patents

Description

The invention relates to the processing of metals by pressure, in particular to the coating of linings from sheet blanks, and can be used in aircraft manufacturing, shipbuilding, automotive and other engineering industries, where large sheet parts are used.

The purpose of the invention is to reduce the labor intensity of installing the sheet blank into the clamping jaws as a result of the elastic reduction of the shape of the curved blanks and the elimination of manual labor.

 The drawing shows a diagram of an apparatus for carrying out a method for installing a sheet stock.

Plates 1 and 2, having wavy working surfaces 3 and 4 with height and waviness step, respectively, t and Е, are installed with the possibility of their vertical movement. At some distance from the clamping jaws 5 and 6, having working surfaces 7, one of the edges of the sheet blank 8 is located,

The method is carried out as follows.

On the lower wavy surface 4 of the plate 2, the workpiece 8 is installed so that its end hangs from state 2 by the amount A, selected in accordance with the depth of the shed E of the clamping jaws 5 and 6. The plate 1 is lowered from above and, pressing the workpiece, corrugates it. Since the height of the corrugations t is less than the distance H between the clamping jaws, when the clamping jaws move to the corrugated end of the workpiece 8, the latter easily enters the jaws between the jaws. After this, the upper plate 1 moves upwards, and the clamping jaws 5 and 6 clamp the workpiece.

Dp of the free entry of the corrugated end of the billet into the sponge jaws, the height of the corrugations t is chosen equal to 0.8-0.9 distance meazda clamping jaws H,

Deformation during shirring is performed in the elastic-plastic region.

If it is assumed that the shape of the corrugations is performed in the form of conjugate segments of a circle, then in this case the step of the corrugation wave can be determined by the formula

(ABOUT

212651 where

/ 2 - half-wave corrugation, m} - Yaoluvoln corrugation, m,

R is the radius of the medial surface of the corrugation in the treatment, which is perpendicular to the surface of the Corrugation, m. The radius of the corrugation can be represented

ten

as

(2)

where S is the thickness of the sheet, the degree of deformation of the extreme

edges of the bent corrugation. At the same time receive a step of corrugations

 (3)

The degree of deformation of the sheet during the formation of corrugations should be 20 equal to the beginning of the plastic deformation I, 6,

i, i.e. E-g- In this case,

when pressed, the corrugations disappear completely. Substituted in the formula (3) value finally get the size of the step of the corrugations

i (ES

5t

-t)

(four)

Example. In a skid machine, the distance between the jaws in their open state is H 20 mm. Must be installed in the sponge duraln {niyev sheet with thickness | Shchina S 3 mm, width In tOOO mm, (FROM material D16AT sp., E

1 72000 MPa, 6 150 MPa. The height of the corrugations t 0,8 N 0, 16 mm.

Corrugation wavelength

40

g 20,016 (

2-72000 0.003

150

- 0,016) 0,214 m.

The active length of the corrugated section B p, equal to the width of the plates 1 or 2, is chosen from the condition of see-a; leaf surfaces. In order for the sheet not to appear prints from plates 1 and 2, it is necessary that the greatest pressure created by the protrusions of the plates does not exceed half the yield strength

. t PC

bsn, 5bt

where 6tM is the voltage, see, MnaJ is the force, cm, H;

PC F

- contact area, m J

6t - yield strength, MPa.

where bp sn

hence the length of the corrugated section Bp is active or the plate width is equal ..,

.- the length of the corrugated section is active, m} - the actual contact width, m.

Accepting the data given in the example determines the active length of the corrugated section.

Contact area allowed

Effort see ty p equals

: l ..

where Hi, j - bending moment when the sheet is corrugated;

MHJ WT -bt

where by | t is the moment of resistance when the end is corrugated,

.,.

WT - i; 1

Editor E. Papp

Compiled by S. Shibanov

Tehred O. Niece Proofreader L. Patay

Order 694/16 Circulation 783 Subscription

VNIIPI USSR State Committee

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

Branch PPP Patent, Uzhgorod, st. Project, 4

S

- length.

the end of b,

S - sheet thickness, m 1, 003

five

0,0000022

M

"Y

0.0000022 150 0.00033 Mnm; , 00033 0.302

0.0437 mn;

0.0437

0.00058 m

0.5 150 where the length of the corrugated section is active

;AT"

0.00058 0.02

0.029 m

Accept Bp 30 mm.

The advantage of the proposed technical solution over the known one is to reduce the laboriousness of the process of covering by eliminating manual work, which makes it possible to completely mechanize and automate the process of covering.

Claims (1)

METHOD FOR INSTALLING SHEET Billets in the WINDING of CLIPPING SPONES of the TIGHTENING MACHINE, which consists in clamping the part of the workpiece located along the edge to the supporting surface and pushing the jaw of the clamping jaws onto the edge of the workpiece, which is to reduce the complexity of installing the sheet workpiece in the clamping sponges, the part of the workpiece pressed against the supporting surface is positioned from the edge at a distance equal to the depth of the jaw of the clamping jaws and during the clamping process these parts of the workpiece are corrugated by deforming into elastic-plastic oblast, thus forming waves directed perpendicular to the edge of the pinch, and the height of the undulating surface is 0.8-0.9 distance LKAU jaws.