SU96094A1 - The method of manufacturing sheet products of double curvature from flat blanks and a machine for its implementation - Google Patents

Description

Known methods for manufacturing double-curved sheet products by successive flat billet formation provide for the formation of double curvature sheet products on three-roll drive cylindrical rollers with gaskets of various thickness, which regulate the change of the ring curvature, or on the presses by fitting one-sided stamping on a narrow flat stamp, and changing curvature in the meridian direction, it is achieved by changing the course of the punch simultaneously with the movement of the sheet across with ujTaMoa.

With these methods, the compressive stress in the extreme areas leads to local loss of material stability and the formation of waves and wrinkles until the required plastic deformation of the stretch is compressed along the middle surface.

The lack of conditions for the regular distribution of deformations of the middle surface and the discrepancy between the mutual position of the tool (rolls and dies) in the final shape of the part being machined make the known methods inefficient and exclude the possibility of automatic control of curvature during the bending process. Ethn methods require special skill of the personnel, performed their bending, and cannot provide the necessary details for assembly and welding.

In the proposed method, the manufacture of double curvature sheet products is carried out first by bending the flat blank in one direction by clamping it between the pads arranged in several parallel curves, and then turning each row, except the first, near the axis located between it and the previous row at the level of the center of gravity of the curves of these rows.

In this case, as a result of the appearance of plastic deformations, the shell takes the shape of the surface of rotation of the arc of constant radius.

FIG. Figure 1 shows a double curvature sheet product, side view; in fig. 2-in the left part-machine, front view, in the right-machine in longitudinal section.

The described machine consists of five rigid frames with hinged soy .Vo 96094,

linear with one another. One of the extreme frames (first) is rigidly supported on the base frame /.

The structure of each frame includes two vertical posts 2, the lower iieno-sliding beam 3 and the upper crossbar 4.

In the grooves of the pillars of each frame, the screws 5 move the upper beam 6. The upper and lower beam pieces have sockets into which the pads are laid. 7, forming work surfaces to pinch the sheet to be bent.

The pinching surfaces of the pads, with the exception of the pads of the outermost miM, may have an outer covering, for example a rubber covering.

The screws 5 of the adjacent frames are connected to each other by textolite gears S.

The screws of the middle frame through a bevel gear .9 and the shafts 10 are connected to a worm gear 11, which is driven by an electric motor 12 mounted on this frame.

The frames are interconnected and; ariyras, consisting of ylanok 13 with pegs 14, which are covered with iodiships 15. The bars are rigidly attached to the uprights of the three-dimensional frames (iervoy, third and fifth), and the iodishpniki are to even frames (irropoii and fourth). The axes of the hinges are positioned at the level of the center of gravity of the cross-sectional curve: 1-11 sheets.

The upper ends of the frames are interconnected by a system of levers 16 p 77, angled one to another and successively connected by parpiers 18. The ends of the 16 niapinipaMn levers are connected to the CToiiKa.Mii of the outer frames, and the middle of the levers are 17-with the middle frame levers. These levers provide the raviomerica angular displacement ral relative to each other.

 At the upper ends of the first frame, D15a hydraulic cylinders 19 with pistons 20 are installed, the rods 21 of which are attached to the earrings 22 are connected to the nose frame (fifth) frame.

The machine operates in the following way.

In the initial position, everything should be in a vertical plane. The motor 12 is turned on, the movement of which through gear Y / and bevel gear .9 is transmitted to the screws of the middle frame and through gears 8 to all the other screws. The upper beams are lifted simultaneously by screwing in the screws.

On the roller 23, a bending sheet is inserted between the upper and lower beads, and then the motor is rotated in the opposite direction and the sheet is clamped, taking the shape of a sheath of zero gaussian curvature.

In the left (according to the drawing) cavity of the hydraulic cylinders, pressure is created, which causes the mouths to move and cause the mobile extreme frame to rotate. At the same time, momeite develops on the pads of the outer frame, under the action of which the shell bends and assumes the outline of the surface of double curvature.

The levers 16 and 17 drive the middle frames, and simultaneously simultaneously increasing corners are formed between the frames.

Thus, the levers 16 and 17 ensure uniform distribution of the deformation in the direction of bending.

The radius of the bend at each given moment is controlled by the scale 24 and the arrow 25, driven by the lever 16.

When the bending radius reaches a predetermined value, the left cavities of the hydraulic cylinders are connected to the drain. In the right cavities, a pressure is created; it is necessary to balance the moment of the weight of the mechanism with respect to the hinge of the first frame. Since, at this, the mechanism's effect on the bend (1), children, elastic deformations, is eliminated, it should disappear.

Freeing yourself from elastic deformations, the part will carry out the mechanism ... in the 1st case, corresponding to plastic deformation. Using the dial and hands, the radius of bending of the plastically deformed part is determined.

After obtaining the desired curvature in the area to be machined, the upper beams rise, the sheet moves a length equal to the machining step, the frames are adjusted to the vertical position.

The most flexible process is repeated as outlined.

The described machine is intended for the manufacture of drop-shaped tanks, but it can also be used for the manufacture of other curvatures with a JiHCTOBbLx product.

Subject invention

Claims (4)

1. A method of manufacturing double curvature tiste products from flat blanks, so that the workpiece is first bent by clamping it between the pads arranged in curved parallel rows, giving the shape of the shell a zero gaussian curvature, and then each row of blocks, except the first one, is rotated near the axis, located between the pym and the previous row at the level of the center of gravity of the curves of these rows 2. A machine for carrying out the method of) n: 1, of which there is made in; 1 type of several frames with curved pads of shoes in each of them, except for sharpened consistently with each other at the level of the center of gravity of the curves of these rows, and above the hinge articulated with double-arm links, with the first frame mounted on the machine bed stationary and carrying on its upper edge two hydraulic cylinders, the rods of which are connected using earrings my. 3. Form of execution of the machine pop. 2, that is, with the fact that the pads of each row are mounted in two beams, of which the upper is made adjustable in the guides of the lateral vertical pillars of the frame. 4. Application for simultaneous interleaving of the upper beam of screws, which are mated with the aid of gear pairs with the screws of the middle frame, which in turn are mated by gear with the gearbox of an electric motor, mounted on the middle frame. 2 / II 22 Fig 2