DE1300423B - Method and device for manufacturing an aerodynamically profiled blade for flow machines - Google Patents

Description

The invention relates to a method for producing a aerodynamically profiled blade for flow machines, which consists of a foot, a Leaf and a transition area between these and delimited by fillets consists of a pre-pressed, blade root and blade having blank, and on devices to carry out this procedure.

With modern turbo machines makes the required accuracy machining operations related to the dimensions of the blade, such as grinding, Polishing and re-polishing are required and these operations are costly and time consuming. In the known manufacturing process for the blades can the blades have surface defects such as folds, overlaps and cold welds, to adjust.

It is a method for manufacturing blades for flow machines known, in which from a rod section initially a raw sheet in the extrusion process is produced. Then the foot is upset, and then the sheet is cold rolled, twisted, pre-pressed and finished. In these procedural steps you can disadvantageous material deformations, in particular a disadvantageous material flow in the vicinity of the foot, and that leads to inferior shovels.

It is also known to mold blades for flow machines forge or stretch by rolling. During this stretching, the blank can after Required in repeated work steps from the shovel root to the finished form to be pulled. However, this can cause the material to flow at critical points the shovel cannot be prevented.

Another method is known in which a blank is rolled and pressed thereon in order to obtain the twisting of the airfoil. Here undesirable flow can also occur.

The invention is based on the object of a method and devices to create blades for turbomachines, with the simplest Process steps and shoveling with the simplest means of excellent quality can be produced that no longer have any surface defects.

According to the invention, by pressing the blade blank in the transition area the fillets are preformed on opposite sides of the blank, in the process being the surface of the foot facing the leaf is formed, then the leaf becomes more familiar Rolled away from the foot and pulled in the opposite direction, the sheet is then embossed to have the profile twist and the inclination opposite given to the surface of the foot facing the sheet, and at the same time received the The foot and the transition area by pressing the top surface of the foot and the fillets the final shape and finish, and finally will be in itself known way the sheet is trimmed to the final dimensions.

Due to the formation of the fillets, in the further processing step disadvantageous material deformations, in particular disadvantageous material flow in the vicinity of the foot. By rolling the sheet away from the foot and it is pulled in the opposite direction, in particular a Prevents the material from flowing at critical points on the blades. Especially advantageously, after rolling, the sheet is twisted by embossing and is given an incline, and at the same time the upper surface of the foot and the fillets are compressed so that the foot part, the transition area and the Sheet is given its final shape and surface texture. So it will a high quality shovel with the simplest work steps thanks to the invention manufactured.

The device according to the invention for performing the method can have two toggle levers arranged symmetrically to the longitudinal axis of the sheet, which at their ends facing each other, stamp surfaces for attack on the transition area wear, and a plunger that engages the toggle levers. In advantageous Way stops for the end position of the toggle lever can be provided. Here can the pressure stamp have a recess to accommodate the foot. Preferably can die-like recesses on the stamp surfaces for shaping those facing the sheet Connect the surface of the foot.

A device for carrying out the method can also be a pair of rolling jaws have, according to the invention, the one rolling jaw movable along an arc whose center of curvature is opposite that passing through between the rolling dies Center line is offset by an angle to the other die. In advantageous Way, each roller jaw can be connected to a rod, the free end of which on is hinged to a balance beam, which can be moved by a hydraulic drive is. It can be useful to provide a carrier for the blade blank, which is arranged in a carriage that can be moved towards and away from the rolling dies is, and a spring that the carriage at a predetermined distance from the rolling dies holds, with guide surfaces on the rolling dies for the contact of the upper surface of the Shovel blank and an operating lever for the carriage are provided to the Bring the blade blank to the guide surfaces. It can expediently the carriages have guides in which the carrier is pivotably guided on pins, and actuating devices for pivoting the carrier can be provided.

The device with a pair of dies for performing the method can, according to the invention, also have abutments for the foot of the rolled blade, the one with the movable die via wedge drive surfaces on the die pair are too pressable. The abutments can consist of two parts, of which one is movable in the same direction of the movable die.

An exemplary embodiment of the invention is shown in the drawing. Therein F i g. 1 shows a perspective illustration of an initial blank, F i G. 2 shows a partially sectioned illustration of the blank after pressing in a Extrusion press and before removing the blank therefrom, FIG. 3 a perspective Representation of the blank after extrusion, F i g. 4 a section Section through the extruded blade blank in a device after of the invention, before pressing, through which a semi-finished product or a preliminary Shape of the blade is formed, F i g. 5 is an enlarged, partial section through the parts according to FIG. 4 after forming the fillets, F i g. 6 a section Section through the parts according to F .i g. 4 in their final positions in which the preliminary shape of the blade is formed, FIG. 7 is a schematic representation an embodiment of the device for preliminary shaping of the blade, FIG. 8 shows a force diagram to explain the mode of operation of the device according to FIG. 7, F i g. 9 is a perspective view of the pressed blade blank, which also is designated as a semi-finished product or preliminary form of the blade, FIG. 10 to 13 partial sectional views to illustrate the introduction of the Semi-finished product in the rolling device according to the invention, F i g. 14 a section Section through the parts according to FIG. 10 and the semi-finished product after further shaping Machining operations, F i g. 15 a partial section of the semifinished product in the rolling device in a position shortly before rolling, FIG. 16 a section Cut of the blade in the rolling device shortly after the start of the rolling process, F i g. 17 is a partial section to illustrate the state against End of the rolling process, FIG. 18 is a perspective view of the blade after rolling, FIG. 19 is a schematic side view of an embodiment for shaping metalworking and for rolling in the fully open position, F i g. 20 is a section along line 20-20 in FIG. 19, fig. 21 a something exaggerated schematic representation of the manner in which the rolling dies are after F i g. 10 to 13 for engaging the blade in its preliminary form and returned be, F i g. 22 and 24 are schematic representations corresponding to FIG. 19 with others Positions of the parts, F i g. 23 a partial section through the rolling jaws in the practically closed position on a larger scale, FIG. 25 to 28 excerpts Cuts through the embossing device for the tentatively shaped blade after the Rollers in different positions during embossing, FIG. 29 a perspective Representation of an embossed and pressed shovel and FIG. 30 a perspective Illustration of the clipped shovel.

The invention particularly relates to the operations to be performed on a roughly shaped blade blank 10 (FIG. 3). Although the blade blank 10 can be produced in various ways, it is preferably made by extrusion from an initial blank according to FIG. 1 manufactured. A press ram 11 (FIG. 2) presses the material through a die 12, the starting blank having previously been heated to the required temperature in order to facilitate the pressing. After pressing, the blade blank is cleaned in preparation for the next working step. The blade blank 10, the semi-finished product 13 according to FIG. 9, the rolled blade 53 of FIG. 18 and the embossed and trimmed blade according to FIG. 29 and 30 consistently have a foot 10 b, which has a lower surface 10 e (FIG. 4), an upper surface 10 s and a sheet 10 a . The transition region 10 t of the blade blank to be provided with flutes 10 f (FIG. 5) has a cross section which gradually widens from that of the adjoining part of the blade until it merges into the upper surface 10 s of the root 10 b.

In order to reduce the risk of surface defects occurring as a result of the need to convert the blade blank 10 into the essentially finished blade according to FIG. To reduce the required shaping operations to a minimum, the blade blank is first processed into a semi-finished product 13 (FIG. 9 and, more precisely, in section in FIG. 6). For producing this semi-finished product of the blade blank 10 between the opposed die faces 14 a and 15a of a pair of press dies 14 and 15 (F ig. 4) is inserted, so that these pressing surfaces t engage the upper face 10 in the vicinity of the transition region 10. The punches 14 and 15 are in turn arranged on toggle levers, which will be described below, and are arranged so that when a force 17 is applied via a pressure punch 16 on the lower surface 10 e of the blade blank 10 by the movement of the punch on arcuate paths 18 and 19 (FIG. 4) forces 20, 21 (FIG. 5) directed at an angle are brought into effect, which are exerted on the upper surface 10s and reshape this surface and its areas, with gently curved flutes 10f which lie between the upper surface 10s and an area of substantially reduced cross-section in the sheet 10a (FIG. 9) which is intended to form the profile part.

When the transition areas 10 t are reshaped, the punch surfaces 14 a and 15 a act on the upper surface 10 s and the transition areas 10 t in a manner that is shown in FIG. 4 can be illustrated by the movement of the punch surfaces 14 a and 15 a at an angle to the transition areas 10 t and into them. In this illustration, the action and in the assumption that the foot 10 b is located at a given moment in a fixed position, it follows that, while the punch faces 14a and 15a of the upper surface forming 10s, which cause a shift of the metal. A portion of the displaced metal moves along the upper face 10 against the sheet 10 a. Another part is moving outwards. At the same time, the sheet 10a is lengthened by the reduction in cross-sectional area in the area lOr in the vicinity of the flutes 10f . In the end position of the die faces 14 a and 15 a (F i g. 5), the smoothly curved grooves 10f connect the foot 10 b and the region 10 r of the blade 10 a, whose cross section is reduced. As a result of the gentle flow of a minimum amount of metal in two directions, creases, overlaps and cavities closed by the surface and underlying it, which are known to the person skilled in the art as cold welds, are avoided. In Fig. 5 the rams 14 and 15 are shown in their end position, but the forming operations are not yet finished. Slight vacancies or empty spaces 23 not filled with metal remain at the edges of the upper surface of the blade blank. These cavities 23 are filled in that the foot 10 b is compressed in the following way: While the rams 14 and 15 in the in F i g. 5 are brought to a standstill, the forces 20 and 21 of kinetic forces become holding forces. The force 17 (FIG. 6) then causes the metal to flow into the cavities 23. This flow of the metal is the result of an upsetting effect which, although not required, sometimes also causes a slight flow of the metal on the lower surface 10 e outwards into the recess 16 a, as best shown by the ridge 10 m in FIG. 6 and 9 is illustrated.

The explanation of the essential features of the invention has in the above description made a stepwise treatment necessary. How however is explained below, the operations described are in practice smoothly, continuously and quickly executed by operating a press that leads the plunger 16 from its initial position to an end position from which it then returns to its starting position.

In a preferred embodiment of the invention (FIG. 7), the rams 14 and 15 with their curved punch surfaces 14 a and 15 a are supported by two toggle levers 25 and 26, the other ends of which each have a pin 27 and 28 on one Frame 30 are articulated. These toggle levers 25 and 26 , in conjunction with the blade blank 10, produce an effect which, when a substantial force is exerted on the lower surface 10e of the blade blank, generates reaction forces R (FIG. 8), which act on the transition areas 10 t of the blade blank 10 reach. With the displacement of the toggle levers 25 and 26 from their initial position towards their end position, these forces R experience a rapid increase.

In the initial position, the toggle levers 25 and 26 are each inclined at an angle x relative to a line 31 connecting the axes of the pins 27 and 28. This angle x is preferably relatively small, even when the toggle levers 25 and 26 are in their initial positions, and decreases to 10 ° or less, while the toggle levers move around their pins in those directions where the distance between the Stamp surfaces 14a and 15a decreases, so that the gently curved flutes 10f are formed and the cross section of the area 10r of the profile section is reduced following these flutes. More precisely, when the total actuating force P (FIG. 8) is brought into effect on the lower surface 10 e of the blade blank by the mechanically or hydraulically actuated pressure ram 16 , opposing reaction forces p 'arise. Mathematically, P = 2 p '. However, the reaction forces R are greater than the force P applied and are a multiple of each of the opposing forces p '. Expressed mathematically is Since the sine of this angle approaches the value zero as the angle * approaches the value zero, the forces R rise very quickly and strive towards a limit value of infinity. In other words, the reaction forces R increase with a decreasing sine of the angle x between the triangle side p 'and the hypotenuse R of one of the force triangles according to FIG. B. The limit of the forces R is limited by an expansion of the frame 30. Although this expansion is only slight, it plays a major role in monitoring the magnitude of the forces acting on the blade blank 10.

From the previous discussion of the plan of forces and the manner in which the reaction forces R are directed at an angle against the transition regions 10t, it can be seen that the metal-forming forces can consist of forces which occur simultaneously with the exertion of a force on the lower surface 10e of the blade blank come into effect directly on the toggle levers 25 and 26 and the blade blank in the form shown in FIG. Hold position and 7 illustrated between the punch surfaces 14a and 15 a, until the ram in its F i g. 5 and 6 have reached the end position shown.

As in Fig. 4 to 7, the plunger 16 for exerting the force is provided with a recess 16a in which the foot part of the blank 10 is received with play. The sum of the depths of the recess 16 a of the recess 32 formed between the stamp constructions (FIGS. 4 and 7) is chosen so that when the pressure stamp 16 is in its end position according to FIG. 6 is brought, the thickness of the foot of the semi-fatty blank is clearly determined .ist. The end face 16 b on the edge of the pressure stamp (FIG. 5) then rests against the upper surfaces 14 b and 15 b of the stamp, which form a stop for the pressure stamp 16. In this way, the desired thickness, which is required in order to achieve the properties of the foot of the semi-fatty blank according to FIG. 9 to achieve, corresponding to the sum of the depths of the two recesses 16a and 32 predetermined. The recess 32 formed by the rams 14 and 15 has walls which also determine the dimensions of almost all side wall parts of the foot 10 b, since the metal of the foot is compressed so far during the upsetting process carried out by the device that between this and the walls of the Recess an intimate contact occurs. The recess 16a in the plunger 16 is, however, of greater clear width than the recess 32, so that it forms a free space around the circumference of the lower surface 10e and forms the space required for the aforementioned flow of the metal for receiving the burr 10m. This flow of metal occurs to different degrees during the upsetting process, depending on the amount of metal initially present in the foot part in question and as a result of the extrusion process described above. Although the mass of each foot part is relatively uniform, a certain fluctuation occurs, which leads to the fact that the burrs 10m turn out differently or the flow of the metal takes place in different degrees. Like F i g. 6 shows, in most cases some space remains free around the final, possibly occurring ridge 10m. In the end position of the punch, the blade blank is reshaped in such a way that the individual surfaces nestle closely against all of the wall surfaces forming the recess 32 and correspond to their shape. As shown in FIG. 7, when the toggle levers 25 and 26 are moved downwards with a decreasing angle, their lower parts come to rest against fixed stops 33 and 34. As soon as the toggle levers abut these stops, the reaction forces R become holding forces. Further application of the force P creates the final upset just described. At this point in time, the force P can be reduced from zero hydraulically by actuating control valves or mechanically by the passage of the device generating the stroke through its dead center position. Subsequently, springs 35 and 36 cause the toggle levers 25 and 26 to pivot back into their starting position. At the same time, a piston or a spring device 37 is effective and brings about an upward movement of an ejector 38, which extends through an opening in the frame 30 and comes to rest on the blade 10a, and this ejector moves the blade blank out of the toggle levers. The upward movement of the toggle levers 25 and 26 is limited by adjustable stops 39 and 40 on these levers.

The angular movement of the press rams 14 and 15 with their stamp surfaces 14 a and 15 a, which are in predetermined starting positions according to FIG. 4 and 7 ensure the exact position of each blade blank. This is of great importance if the properties of a certain alloy make it necessary to repeat the treatment step in order to convert a blade blank 10 from its original shape to the desired dimensions of the semi-finished product 13 according to FIG. 9 bring. Since each part is reliably and automatically brought into position with respect to the punches, the metal-forming operations are always carried out on the upper surface 10s including the transition areas 10t adjacent to the sheet 10a.

When the semifinished product 13 has been brought to its desired dimensions, which generally also includes a reduction in the cross-section of the area 10r adjacent to the fillets 10f to a somewhat larger dimension than the final cross-sectional area of the finished profile section, the second step of manufacturing the finished blade After removing any burrs, start 10m from the preformed shovel.

In some cases it is desirable to have the semi-finished product 13 before starting to clean the now to be described operation of molding by rolling and to soften. Cleaning is important in those cases where the blade blanks, on which the preforming or pressing processes are to be carried out, defective, z. B. have oxidized surfaces.

Like F i g. 10 shows, is the semi-finished product 13 according to FIG. 9 held securely by a Haheeinrichtung 42, which is under an upward pressure, but moves down in the direction of arrow 43 so that it pushes the semi-finished product between two rolling jaws 44 and 45. To reduce the distance between the shoulders 44 a and 45 a and the curved sections 44 c and 45 c each one of the two jaws connecting, curved, metal-forming corners can be displaced relative to one another. As shown, the die 44 is moved downward. When he comes to rest on the sheet 10a, he tilts it down, and at the same time the holding device 42 moves the semi-finished product 13 inward against the shoulders 44a and 45a. In the end position of the parts (FIG. 14), the upper surface 10s of the semifinished product 13 is pressed against the shoulders 44a and 45a by a force indicated by the arrow 46, and no upward pressure is any longer on the semifinished product.

As can be seen from the following, the holding device 42 is in such Meise mounted that after the roller die 44 on the upper surface of the sheet 10 a (F i g. 10) has come to rest, is rotatable., And it stands as a whole under a load to maintain the system between the sheet 10 a and the rolling jaw 44, but without this loading of the mentioned rotary movement Opposes resistance. The semi-finished product is on this `quietly safe in his Position placed between the rolling jaws, and the device is suitable for the semi-finished product to be recorded for a sequence of operations of the type described below, without the risk of leaving scars and an undesirable one Damage to the blade surfaces and especially the upper surface 1.0s occurs.

According to FIG. 11 to 13 of the rolling jaw 44 is against the semi-finished product13 and the other rolling jaws 45 guided along a curved path, which is still detailed on the basis of FIG. 21 will be described. This trajectory is generally through the successive positions of the rolling die 44 and indicated by arrows 41, which illustrate the change in direction of movement.

As in Fig. 11, increases as the pivoting movement progresses of the semi-finished product through the rolling jaw 44 towards the rolling jaw 45 the size of the gaps 47, 47 a, 48 and 48 a. It is because of the upward-facing, on the semi-finished product acting load caused by a plunger 99 in a manner to be described is generated, the gap 47 is larger than the gap 48. Because of These gaps or gaps are shown somewhat exaggerated for clarity. The semi-finished product is thus produced generally in the direction of the arrow 43 against the two rolling jaws and at the same time moving downwards.

The rolling brook 44 moves the semifinished product 13 further in the direction to the rolling jaw 45 until the semi-finished product comes to rest on the rolling jaw 45 (Fig. 12). The semi-finished product 13 is still below the upward one Load, and this allows bringing about an accurate and snug, zndefi Position of the rounded front card of the rolling die 44 between the shoulder 44a and the section 44 c in the groove of the semi-finished product. While this front edge of the rolling die 44 fits into the groove, are used for shaping and forming of the area of the fillet brought about forces, their resultant by the arrows 49 and 49 a (FIG. 13) are marked. The semi-finished product 13 is ready now no longer under the upward load. Like F i g. 13 shows are at 47, 48, 47a and 48a there are still gaps, but they are now almost are symmetrical about the center line 110.

The forward movement of the holding device 42 is preferably brought to a standstill when the parts are in the position according to FIG. 12 have approached. When the rolling jaw 44 is approximately in the position according to FIG. 13 arrives, the locking device is triggered by the movement of the roller jaw 44. The holding device 42 is then inevitably moved in the same direction as the rolling jaw 44 until the parts reach their end positions according to FIG. 14 reach. The upper face 10 then rests on the shoulders 44a and 45 a. At the same time, a substantial force is brought into effect in the direction of arrow 46 (FIG. 14). Now all other required forming work on the upper surface 10s and on the fillets to adapt them to the surfaces of the rolling dies 44 and 45 is carried out. As best seen in Fig. 11 to 13 can be seen, the holding device has opposite horizontal surfaces 42 a and 42 b, which cooperate with guide surfaces 44 b and 45 b and bring about a fixed and repeatable, mutual position of the foot 10 b and the sheet 10 a in the vertical direction. When this mutual position is established (FIG. 13), a reaction force in the direction of arrow 49a occurs as a result of the force in the direction of arrow 49, which moves the rolling jaw 44 into its end position. This reaction force is directed against the flutes at an angle. If the fillets are of a shape that does not exactly match the curved edge portion of each shape, they are now reshaped to exactly match the shape.

As in the following with reference to FIG. 21 is explained, this becomes Positional relationship in the vertical direction through a monitored horizontal positional relationship supplemented, so that an exact and repeatedly brought about location of the semi-finished product 13 with respect to the rolling dies 44 and 45 is guaranteed when successive Rolling passes are to be carried out.

After the position of the semi-finished product between the rolling jaws 44 and 45 has finally been brought about and the pressing of the flutes and the upper surface to the correct dimensions has been completed, the punches are held at a fixed distance from one another for a short time (FIG. 15). At this point in time, the kinetic forces in the direction of arrows 46, 49 and 49 a (FIG. 14) become potential forces or holding forces in the direction of arrows 46 a, 49 b and 49 c (FIG. 15), the Hold the semi-finished product and give the excess metal when pressed to dimension time to complete its flow movement. This length of stay can be determined by a number of the following with reference to FIG. 19, 22 and 24 to be described control devices can be brought about.

The rolling jaws 44 and 45 are now according to the arrows 50 in FIG. 16 rotated against each other to form the sheet 10a in a rolling process. This rolling and forming operation is carried out while the semifinished product 13 is held under a tensile stress indicated by arrow 51 , the magnitude of which is sufficient to prevent the semifinished product from following the curved portions 44c and 45c of each of the rolling dies, regardless of Changes in the peripheral speed of the curved portions 44 c and 45 c is kept essentially constant. The rolling forces are generally indicated by arrows 52. F i g. 16 shows the semifinished product in a by a small amount by the curved sections 44 c and 45 c from the in F i g. 14 and 15 position shown to the right shifted position. The rolling process continues (Fig. 17), the cross-sectional area of the sheet 10a is reduced, and the sheet itself is formed according to the sections 44c and 45c. As the tip of the blade leaves the curved sections of the dies, a force exerted on the retainer 42 pivots the rolled preformed paddle 53 up and away from the dies to a position shown in phantom, from which it, once removed from the retainer 42 is released, is easily removable. The rolled, preformed blade 53 (FIG. 18) has a smooth blade 10a and a thickness that is maintained uniformly over its length. The preformed vane 153, however, is much greater in length and width than is required in its finished form. The illustrated irregularities at the tip end can occur as a result of repeated rolling processes and by an increased distance between the curved sections 44 c and 45 c after the usable part of the sheet has been brought exactly to the desired dimensions, which are to be achieved by the rolling.

F i g. 19 to 24 show a preferred apparatus for post-forming the upper surface of the semi-finished product 13 and for shaping the sheet 10a by the already described rolling process. As shown in FIG. 19 is the rolling jaw 45 carried by a roller 55 which is mounted on a shaft 56 which itself is mounted in upright parts 57a of a frame 57. The roller and the Rolling jaws 45 are therefore held in a fixed position with respect to frame 57. The rolling jaw 45 is by a left movement of a rod 63, which by means of a Pivot pin 62 is hinged to the ends of two levers 61, the other of which Ends attached to the roller 55 are rotatable. The opposite end of the rod 63 is articulated to a balance beam 65 by means of a pivot pin 64. The balance beam 65 is with the piston rod 67 of a hydraulically operated cylinder 68 by means a pivot pin 66 connected at a point near the center of the balance beam 65 and slightly against a line through the centers of the pivot pins 64 and 77 is provided offset to the left.

The movable and rotatable rolling die 44 is carried by a roller 70 which is mounted on a shaft 71. This shaft is guided by the arms 72a and 72b of a supporting structure articulated on the frame 57 by a shaft 73. From the roller 70, levers 74 extend upwards, one ends of which are fastened to the roller 70 and which are articulated to one end of a rod 76 by means of a pin 75. The opposite end of the rod is articulated to the balance beam 65 by means of the pivot pin 77.

A tappet 78 is articulated on the shaft 71. This is driven mechanically or hydraulically and inevitably moves the rolling jaw 44 towards and away from the rolling jaw 45. As already mentioned, these rolling dies 44 and 45 (FIG. 10) have shoulders 44a and 45a which end in curved edges or corner parts which merge into the curved sections 44c and 45c. Since the rolling jaws 44 and 45 are rotatable about the axes of the shafts 56 and 71, respectively, it is important that during the movement of the rolling jaw 44 against the rolling jaw 45, the piston 69 of the cylinder 68 exerts sufficient force to rotate the rolling jaws permanent contact between the rods 63 and 76 and their associated stops 83 and 84 to maintain. This can be done by any means, e.g. By a hydraulic actuation system which normally applies pressure to the left side of the piston 69 and is equipped with a sump 80, a constant volume pump 81, a pressure line 82, a check valve 82a and a solenoid valve 187a. In this arrangement, the piston 69 maintains a pressure in the forward direction, which depends on the raising or lowering of the ram 78 and thus of the arms 72a and 72 b. This causes the rods 63 and 76 to be in the positions shown in FIG. 19 positions shown held. The lower end of the rod 63 rests against the adjustable stop 83 assigned to it and carried by the frame 57. The right end of the rod 76 rests against the adjustable stop 84 assigned to it and carried by a cross member connecting the arms 72 a and 72 b to one another. In this way, while the rolling jaw 44 is being moved against it, the roller jaw 45 does not perform any rotary movement, and the balance beam 65 performs a pivoting movement which compensates for the movements of the rods 63 and 76.

In the pressure line 82 is a pressure relief valve 85 with adjustment devices for predetermining the size of the action to be taken in a cylinder 86 hydraulic pressure and to maintain a minimum pressure in the line 82 and thus provided in the cylinder 68. The pressure relief valve 85 ensures namely, a pressure difference between the pressure cylinders 68 and 86, so that the pressure in the cylinder 68 is at all times substantially greater than the pressure effective in the cylinder 86.

If it is now assumed that the solenoid valve 87 a is in the in F i g. 19 is the position shown, pushes the conveyed by the pump 81 Pressurizing means first the piston 69 to the right, whereby the rods 63 and 76 accordingly the representation led to the system on the stops 83 and 84 assigned to them will. When the pressure in line 82 then reaches the set minimum pressure of the pressure relief valve 85 exceeds, the line 82 b is pressurized. if the solenoid valve 87 b is brought into the position shown in FIG. 19 acts the pressure medium on a piston 88 and moves it to the left. With this movement it displaces air into an air or pressure vessel 89. This compressed air is used to put the semi-finished product13 under tension during the rolling process to set, as well as to a reciprocating carrier 90 in the in F i. G. 19 position shown.

It is assumed that a semi-finished product 13 is in the holding device 42 had been used. This is easily possible because the back and forth Carrier 90 by a roller 91 which is attached to a protruding part 92 of the carrier 90 attacks, is held in an upwardly inclined position. It's cheap, however not absolutely necessary for the invention, the holding device for easier Insertion of the preformed blade into it in the manner shown in FIG. l.9 shown Way to hold in the raised position and then the holding device by Einric'i @ ung 93 to operate so that it holds the semi-finished product securely. The details of this Holding and are conventional and therefore not shown individually.

While the semi-finished product 13 is held and in the cylinder 86 hydraulic Pressure medium is admitted, the switch for putting the movable into operation Carrier 90 actuated. The piston rod 94 moves the carrier 90 on guides 95 of a Carriage 96, with the semi-finished product 13 moving against the rolling jaws 44 and 45 will. The carrier 90 is moved to the left until a stop 90a and a switching device 90b on the carrier 90 reach a stop 90c on the carriage 96 and the plunger 78 actuate. The carriage 96 is also displaceable and in guides 97 on the frame 57 worn.

As the carrier 90 moves away from the roller 91, it is through the force of gravity or possibly inevitably by a spring, not shown panned. The pivoting takes place around a pin 98, which is mounted on rollers, which run in the guides 95 of the carriage 96. As the carrier descends, comes its lower surface to contact with the plunger 99, the one under an upward directional pressure. This plunger defines the position of the semi-finished product 13 in the FIG. 10 shown angle for the entry between the rolling dies 44 and 45 fixed.

While the semi-finished product 13 is being moved under the upper rolling jaws 44, the switching device 90 b initiates a downward movement of this rolling jaw through the ram 78 . This downward movement, using a mechanical press actuator, is fairly rapid. Therefore, in order to achieve accurate and precise alignment of the semifinished product 13 between the rolling dies before any part of the rolling dies engages the semifinished product, a synchronizing device is provided which comprises actuating levers 101 hinged at 102 and normally the carriage 96 by the action of a Hold spring 103 in its right position. The levers 101 are able to move the carriage 96 a predetermined distance to the left against the rolling dies. Thus, when the adjustable actuation surfaces 104 carried by the arms 72a and 72b engage the upper surfaces of the levers 101, the carriage 96 moves quickly to the left, against the force of the spring 103, and a force occurs which in F i g. 14 is shown by the arrow 46, so that the upper surface 10s of the semi-finished product 13 (F i g. 14) at the same time on the shoulders 44 a and 45 a to the plant, as the bent edge parts of the rolling jaws 44 and 45 against the Grooves of the semifinished product 13 are moved inward in the manner described and come to rest against them. Since the movement of the carriage 96 is brought about entirely by the abutment of the levers 101 on the surfaces 104, a synchronized and exact movement of the semi-finished product 13 takes place in the manner shown between the rolling jaws 44 and 45. In this context, it should be mentioned that the upper Surface 10 s is in contact with the shoulders 44 a and 45 a over a predominant part of its extent for precise alignment and is held against them under a force which is equal to the force supplied by the cylinder 86. The cylinder 86 acts of any further movement of the carriage 96 past the point, the upper surface is in the 10s in the embodiment shown in F i G.14 and 15 manner with the shoulders 44a and 45a into abutment against. Such further movement of the carriage 96 cannot be transmitted to the traveling carriage 90, since there is a corresponding movement of the piston rod 94 to the right with respect to the carriage 96 and this movement with respect to the movable carriage 90 carried by the carriage 96 holds stationary on shoulders 44a and 45a. The levers 101 are mounted in the frame 57 with; adjustable stops 105 for adjusting the distance of movement of the carriage 96 under the influence of the spring 103.

Since the shoulder 44 a of the upper roller die 44 (F i g. 10 to 13) is inclined at an acute angle with respect to the curved section 44 c, it is important to limit the possibility to a minimum that the curved corner or edge portion of the die 44 comes into contact with the upper corner of the semi-finished product 13 while the dies are moved inward. Correspondingly, the roller jaw 44 (FIG. 21) is arranged to be pivotable along an arc 107, which can be described as inclined away from the end position of the upper surface 10s. Expressed more precisely and as shown in FIG. 21 is best seen, excludes a tangent 108 to the arc 107 of the rolling die 44 from the intersection 109 of this arc with the center line 110, which is formed by the profile rolling center plane between the rolling dies 44 and 45, with a right angle to this center line Straight line an angle d. This inclination at the angle d is achieved in that the axis of the shaft 73 carrying the arms 72a and 72b is placed at a point which is closer to the die 45 than to the die 44 or, more precisely, that of the center line 110 is offset from against the rolling jaw 45, as shown in FIG. 21 is illustrated by the somewhat exaggerated angle X.

F i g. However, 21 alone does not fully show the position of the rolling die 44 when passing through its movement arc 107. In FIG. So 21 is the bow shown as passing through the curved edge portion of the die 44.

As best seen in Fig. 19 and 20 can be seen, the rolling dies 44 and 45 are carried in their center by the rollers 70 and 55, and the caliber (Fig. 23) is arranged in such a way that on either side of the cavity 112 between the rolling dies a very slight Game 114 or 115 remains. When the rolling dies are in the position shown in FIG. 22 and 24 are positions shown, the edge parts 55 a and 70 a on the rollers 55 and 70 touch each other so that they absorb the downward force exerted by the plunger 78. The rolling pressure on the profile section of the rolling die is therefore not exerted directly by the rams 78, but rather indirectly. The edge parts of the rollers 55 and 70 can namely be loaded to a greater extent than is actually required for the roller jaws 44 and 45. This increased load ensures that the rolling jaws carry out their rolling activity properly, since the forces required for rolling are maintained regardless of any, even minor deformations that could occur in the device. This plays an important role in achieving a high quality of the product. Like F i g. 20 shows, shock absorbers 116 in the form of rubber buffers can be provided on the frame 57 in order to absorb the kinetic energy of the plungers 78 and the parts connecting them. In this way, damage to the edge parts 55 a and 70 a is avoided.

As already in connection with F i g. 11 to 15 mentioned, the surfaces 42 a and 42 b on the holding device 42 with the guide surfaces 44 b and 45 b of the rolling jaws cooperate in such a way that between the foot 10 b and the sheet 10 a a fixed and repeatedly brought about positional relationship in vertical direction. A similar solid and repeatedly brought Viable positional relationship in the horizontal direction by the surfaces 70 b and 55 b (F i g. 20) in conjunction with vertical side surfaces 42c of the holding device 42 (F ig. 19) is set. In this way, by means of the guide surfaces on the edge parts and the rolling jaws in conjunction with the guide surfaces on the holding device, a fixed and repeatedly achievable positional relationship of the semifinished product 13 can be established in both the horizontal and vertical directions. This arrangement for bringing about an exact position enables high accuracy in the successive rolling passes, eliminating the risk of damage due to slippage or abrasion when treating the already formed surfaces again.

When the rolling jaws are closed (FIG. 22) and the fillets are moved by the movement of the push rod 78 from their starting position into their end position for guiding the rolling jaws into their end positions according to FIG. 14 and 15, when the arm 72a hits a timer 113, the solenoid-operated valve 87a is activated, which transfers the hydraulic pressure to the right side of the piston 69 to move the piston rod 67 to the left. The bars 63 and 76 are moved by the balance beam 65 and rotate the rolling jaws 44 and 45 for rolling the profile sections in the manner described in detail above in the directions indicated by the arrows 50 (FIGS. 16 and 17).

When, after actuation of the valve 87a, the forces required for rolling act on the rolling jaws, the valve 87b is rotated in such a way that it connects the oil-filled part of the cylinder 86 with the sump 80. As soon as this occurs, the compressed air contained in the container 89 acts on the piston 88 of the cylinder 86, exerts a force on it and moves it to the right. These in FIG. 16 and 17 by the arrow 51 indicated force puts the semifinished product 13 under tensile stress during rolling. The position of the parts during forming by rolling is shown in FIG. 24 shown. At the end of the rolling, the compressed air causes the movable support 90 to return to the position shown in FIG. 19 position, in which he arrives at the switch 113 a to attack, which initiates the lifting of the plunger 78. The spring 103 (FIG. 19) returns the carriage 96 to its right-hand position, the stops 105, which are screwed into the frame 57, serve for the levers 101 and the carriage 96.

It is important to note that the pivot pin 66 between the balance beam 65 and the piston rod 67 is offset to the left from a connecting line between the axes of the pins 64 and 77 of the rods 63 and 76. By pivoting the balance arm 65 (FIG. 24) about the pin 66, the latter brings about an optimal balance between the surface speeds of the rolling jaws 44 and 45 and strives to keep the movement of these jaws in perfect synchronism. This action limits any slippage between the curved surfaces of the rolling dies and the airfoil. In this way, the rolling causes largely improved properties of the surfaces on the opposite sides of the sheet 10a according to FIG. 18 achievable. The fact that such slip is avoided with certainty is a favorable feature with regard to the longer life of the rolling dies. The balance beam 65 is important in every rolling process because one surface of the airfoil is convex and the other is concave, as best shown the illustration of the cavity 112 between the rolling dies (FIG. 23) can be seen, which requires different rolling cross-sectional curvatures on the rolling dies and, in general, a different resistance to rolling. The line of action of the piston rod 67 is offset against the pivot axis of the arms 72 a and 72 b about the shaft 73 upwards. Accordingly, upon completion of the rolling process, a reversal of the movement of the piston rod 67 via the rods causes the two rolling jaws to pivot in opposite directions back to their original positions, regardless of any degree of displacement that may have occurred during the rolling. As a result, the exact return of the rolling jaws 44 and 45 into the fillet 10 f is ensured in the event that subsequent rolling processes are necessary.

At the end of the rolling of the blade 10 a, the valves 78 a and 87 b back into their positions according to FIG. 19 returned.

While the piston rod 67 is displaced to the right in the cylinder 68, the balance beam 65 is pivoted about its pin 66, while the rods 63 and 76 pivot the rolling jaws 44 and 45. At the same time, as a result of the upward movement, the ram 78 of the rolling jaws 44 moves upward. Although the spring-loaded plunger piston 99 has already moved the carrier 90 approximately into the position shown in FIG. 17 has raised the position shown in broken lines, the carrier is moved further into the position according to FIG. 19 tilted, in which the finished, rolled blade can be easily removed by the device 93 after releasing the holding device 42.

After reaching the required number of rolling passes for a preformed one Bucket, this is ready for the embossing processes that are described below.

The first stage (FIG. 25) of the final stamping process consists in inserting the preformed and rolled blade 53 between two stamping dies 120 and 121, which are in the starting position at a distance from one another. The determination of the position of the preformed blade 53 between the dies is achieved in that the foot 10 b is held in a recess formed by abutments 122 a and 112 b, which can be actuated in such a way that they the upper surface 10 s of the foot 10 b of the preformed blade 53 press against shoulders 120a and 121a of the stamping dies 120 and 121 after these are essentially closed (FIG. 27) and their curved corner parts have come to sit or essentially sit on the curved fillets 10 f. These abutments 122a and 122b are moved to positions in which the upper surface 10s of the foot rests on the shoulders 120a and 121a. In doing so, a force 123 (FIG. 27) of a magnitude is exerted that ensures finishing, smoothing or final post-treatment of this upper surface. In order to enable precise regulation of these operations, the abutments 122 a and 122 b are moved in synchronism with the closing of the die 120 and 121. This corotating movement which takes place while the stamping dies to close around the blade 10 a is, as best shown in F i g. 25 can be seen, achieved in that the die 120 and an actuating member 124 are moved together. This happens e.g. B. by a hydraulically or mechanically operated device 125, e.g. B. a toggle press, in such a way that the die 120 is moved against the die 121, the actuator 124 engages with its wedge drive surface 124a on a correspondingly inclined surface 122s of the abutment 122a and this along tracks 130 on the frame 131 at a speed moved to the right, which is preferably greater than the closing movement of the die. The higher speed of the abutment 122a is achieved when the angle measured between the horizontal line of movement of the abutment 122a and the inclined surfaces is less than 45 °.

The upper surface 10s of the base 10b and the grooves 10 f are thereby reformed, that the die attack 120 and 121 on the sheet 10a, but without the metal undergoes in any part of the aerodynamic surfaces of a shift from a type which, to any wrinkles Laps or cold welds.

This embossing process, in which the aerodynamic surfaces are both dimensioned and given their final shape, finally brings about the desired profile shape of the blade. As best seen in FIG. 25 as can be seen, the embossed surfaces 120 b and 121 b each extend upwards at an angle against the shoulders 120 a and 121 a in order to establish a relationship that is suitable for certain types of blades. The embossing surfaces can be at any angle which is determined by the inclination of the upper surface 10s of the foot, which is held at right angles to the direction of movement of the embossing die 120.

For the rolled, pre-shaped blade 53, the embossing surfaces 120 b and 121 b at an angle upwardly inclined such that a line which passes through those points of the finished embossed blade, referred to as a ready reference points against the upper surface 10s at a predetermined angle stands. In this way, the dies, after they come into contact with the surfaces of the sheet, impart a twist or curvature or any other desired, final shape in this section. Advantageously, as mentioned, the embossing stamps can be actuated by a toggle press so that they stand still in their end positions for a short period of time. During this residence time, the metal has time to flow into its final position according to the finished profile.

When the parts are in readiness (FIG. 25) before the embossing process, the abutment 122a is under a load, e.g. B. the pressure of springs 132, which strive to press this abutment to the left against a stop 133. While the die 120 and the actuating member 124 are pressed down (arrow 138), the shoulder 120a of the die 120 has adequate play relative to the upper surface 10s of the preformed blade 53, as indicated at 134 (FIG. 25) in order to minimize the risk of this shoulder engaging the preformed blade during the closing of the dies. The slidably supported in dovetail grooves 122w of the abutment 122a abutment 122 b is under the upward pressure jgerichteten of springs 135, and a shoulder portion located in abutment with a shoulder part on the abutment 122a, in order to limit its upward movement.

As shown in FIG. 26, the outer tip of the blade 10a of the preformed and rolled blade 53 rests on the top surface of the die 121. The edge portion of the movable die 120 engages the blade near the top surface 10s. The wedge drive surface 124a of the actuating member 124 has almost come into contact with the corresponding surface 122s. By the attack of the edge portion of the die 120 to the sheet 10 a, the abutment 122 is b, such as from a comparison of the positions of the parts in F i g. 25 and 26 can be seen, has been moved downwards. In the position of the parts according to FIG. 26 has thus experienced a certain deformation of the sheet 10 a by bending. In this context that the foot 10 b has to be mentioned again, the preformed blade is securely held in the by the abutments 122a and 122b formed recess 53rd In the further course of the closing movement of the dies, the sheet 10a undergoes further deformation by bending upward with respect to the foot 10 b.

While the die 120 moves from the position according to FIG. 26 about the position according to FIG. 27 in the position according to FIG. 28 moves, engages the wedge drive surface 124 a of the actuator 124 on the corresponding surface 122s of the abutment 122a and exerts a force 123 on this, which is derived from a force 139, and moves the abutments 122a and 122b quickly to the right, so that the upper surface 10s rests against the shoulders 120a and 121a of the dies 120 and 121 in the manner described above. The upper foot surface 10s is thus processed (FIGS. 25 and 27) before the sheet 10a is completely embossed. In the end position of the die (FIG. 28), the abutment 122b rests on the frame 131, which prevents it from moving further downwards.

After finishing the shaping of the upper surface 10s including the fillets 10 f and the embossing of the sheet 10 a, the die 120 and 121 are separated and the embossed blade 53 according to FIG. 29 taken. the The blade is then trimmed to the predetermined length and width required for the special blade set is required for a specific machine or machine stage are. The dashed outlines of the blade, trimmed to length and width (Fig. 29) show, somewhat exaggerated, the metal scrap. The simultaneous Trimming to width should meet the needs of the particular aerodynamic application be sufficient that the required thickness at the front edge and at the rear edge of the finished sheet is guaranteed. After the final trimming (Fig. 30) only need to remove the burrs resulting from the trimming and the leading edge and trailing edge of the blade to be rounded slightly to make it aerodynamic Meet the requirements for the intended application. The finished shovel then has one from the front to the back including the front and trailing edges on gently curved surfaces.

Although not required to the invention, the dies are 120 and 121 with a recess 136 and with a projection 137 for cutting out, respectively a hole 138 or for making a recess in the scrap portion of the sheet the embossed blade or for piercing. By attaching a Hole or a depression in the waste part is the distance from the foot to , this hole or the recess can be precisely defined. The is accordingly Cutting line with: the one for making the same blades of identical width and length and with proper alignment with respect to the top surface of the foot and on the points referred to as manufacturing reference points Accuracy can be determined with the help of this reference point in the embossed blade.

After the final trimming, the foot 10b is the finished blade according to FIG. 30 already to the required dimensions for assembly, e.g. B. in the form of driving or driven parts in gas turbines, turbine jet engines or compressors. For applications of this type, the manufacturing cost is largely reduced when carried out according to the invention.

Claims (11)

Claims: 1. A method for producing an aerodynamically profiled blade for turbomachines, which consists of a foot, a blade and a transition area between these, delimited by fillets, from a pre-pressed blank with blade root and blade, thereby marked that by pressing the blank (10) in the transition area (10 t) on opposite sides of the blank (10) the fillets (10f) are preformed and the surface (10s) of the foot (10b) facing the blade (10a) is formed is that then the sheet (10a) is rolled away in a known manner from the foot (10 b) and is pulled in the opposite direction, that then the sheet (10 a) by embossing the profile twist and the inclination with respect to the sheet (10a ) facing surface (10s) of the foot (10b) and at the same time the foot (10b) and the transition area (10 t) by pressing the upper surface (10s) of the foot (10b) and the fillets (1 0f) the final shape and surface properties are obtained and that finally the sheet (10a) is trimmed to the final dimensions in a manner known per se. 2. Device for performing the method according to claim 1, characterized by two toggle levers (25, 26) which are symmetrically arranged to the longitudinal axis of the sheet (10a) and which have stamp surfaces (14a, 15a) at their ends facing each other for attacking the transition area (10 t ) and by a pressure ram (16) which engages the toggle levers (25, 26). 3. Apparatus according to claim 2, characterized by stops (33, 34) for the end position of the toggle levers (25, 26). 4. Apparatus according to claim 3, characterized characterized in that the plunger (16) has a recess (16a) for receiving the Foot (10 b). 5. Device according to one of claims 2 to 4, characterized in that the stamp surfaces (14 a, 15 a) are designed such that they simultaneously with the formation of the flutes (10f) the sheet (10a) facing surface (10s) of the foot (10b). 6. Apparatus for performing the method according to claim 1 and claims 2 to 5 with a pair of rolling jaws, characterized in that the one rolling jaw (44) is movable along an arc (107) , the center of curvature of which is opposite that between the rolling jaws (44, 45) through the center line (110) is offset by an angle (X) to the other roller jaw (45) (FIG. 21). 7. Apparatus according to claim 6, characterized in that each rolling jaw (44, 45) is connected to a rod (76, 63), the free end of which is attached to a balance beam (65) is articulated, which is movable by a hydraulic drive (66 to 69). B. Device according to Claim 6 or 7, characterized by a carrier (90) for the blade blank (10) which is arranged in a carriage (96) which can be moved towards and away from the rolling jaws (44, 45), a spring (103) which holds the carriage (96) at a predetermined distance from the rolling jaws (44, 45), guide surfaces (44 b, 45 b) on the rolling jaws (44, 45) for the contact of the upper surfaces (10s) of the blade blank (10 ) and an actuating lever (101) for the carriage (96) for moving the blade blank (10) to the guide surfaces (44 b, 45 b). 9. Apparatus according to claim 8, characterized in that the carriage (96) has guides (95) in which the carrier (90) is guided on pins (98) , and that actuating devices (91, 92) for pivoting the carrier ( 90) are provided. 10. Device for performing the method according to claim 1 and claims 2 to 9 with a pair of dies, characterized by abutments (122a, 122b) for the foot (10b) of the rolled blade (53), which is connected to the movable die (120 ) can be pressed onto the pair of dies ( 120, 121 ) via wedge drive surfaces (124a, 122s). 11. The device according to claim 10, characterized in that the abutments (122 a, 122 b) consist of two parts, one of which is movable in the same direction as the movable die (120).