DE2303451C2 - Device for forging crankshafts, flange shafts and the like by means of a forging press - Google Patents

Description

The invention relates to a device for forging crankshafts, flange shafts and the like by means of a forging press, in which a split offset tool for producing a crank is arranged between separate upper and lower clamping tools and the carriers Aer upper clamping and upsetting tool halves on a movable one , upper crosshead mounted and the carrier of the lower clamping and upsetting tool halves are hinged by means of a link on the fixed cross or foundation spar, the two tool halves in the clamping position in positive locking with each other and under the action of the downward moving crosshead in the axial direction of the workpiece for upsetting together Are driven like a toggle lever.

In a known forging press (DT-AS 260 932) for successive pressing of the strokes a multi-stroke crankshaft made from a smooth rod, the axially ver pushed between the individual press lines and possibly by the angle! the crank stroke positions can be rotated, two are opposite each other in the forging press frame Hydraulic main drives are mounted, each of which acts on a split upsetting die with a closing pressure transducer. At least one of the main drives is provided with a traveling beam that transmits the compression pressure, with a hydraulic between the upsetting dies

ίο driven bending die arranged for the crank pin is. The main drives press on the upsetting dies via semicircular spacer sleeves, with the An adjustable stop is attached to one end of the rod in the moving beam of one main drive is. This forging press is a special press exclusively for forging of crankshafts and the like. The length of the crankshaft to be forged is limited by the fact that the blank and the finished crankshaft can have a maximum length of the spacer sleeves. With such long spacer sleeves at the same time result long tie rods, which are common with the spacer sleeves Have to transmit tensile force, which leads to considerable rebound at these lengths. Furthermore, the device be rebuilt several times for forging a crankshaft. For forging the first the middle and the last offset require different die inserts. In particular the enforcement tool has a drive that is completely independent of the upsetting tool, with only thereby the independence of the upsetting and enforcement stroke is given. DT-AS 1 049 201 also describes it a forging press for crankshafts, which is a special device tailored to crankshafts and not a device that is used in normal forging presses can. In the well-known crankshaft forging press the independence of the upsetting and enforcement stroke thanks to completely separate drives own control). During the press stroke, there is a control for the ratio of Upsetting and enforcement stroke necessary.

The German utility model 6 606 417 describes a device for upsetting elongated Workpieces on forging presses, with another between two separate upper and lower tools Tool set for bending, in particular for producing crank strokes, is arranged. The upper tools are pivotably supported by articulated levers on an intermediate plate provided on the press ram and the lower tools opposite the press table transversely to the direction of the press ram stroke Arranged horizontally at the front or pivoting by means of an articulated lever. Here are the upper and lower tools designed as clamping jaws with positive locking. The articulated levers are on the back of the Upper tools, if necessary lower tools, and mounted on both sides in the manner of a roller pan and by means of Tabs connected. In this known device, the forming work is both for upsetting as well as for pushing through the ram of a normal press. Here, however, is independence of upsetting and enforcement stroke not given, since the angular position of the articulated lever for the Decomposition into compression and clamping force is decisive and these forces in a certain ratio to each other have to stand. The ratio of upsetting and enforcement stroke can only be determined within a very narrow range.

/.cn can be varied. For a variability of Upsetting and enforcement stroke are not structural requirements for the device of the utility model created. The ratio of the upsetting and enforcement stroke is constant Arrangement made so that a powerful drive unit is required for the second hub, which is in the Practice boils down to the addition of a complete transverse press.

The object of the invention is to provide a device for forging crankshafts and the like by means of a Forging press that can be used for a larger size range by simply adjusting the The upsetting stroke and the enforcement stroke can be used universally and in which the two settings for the compression stroke and the enforcement stroke are independent of one another. At the beginning of the splitting device mentioned type, the invention is characterized in that the carrier of the upper and lower Clamping or upsetting tool halves have a direct hydraulic clamping drive that the upper and the lower clamping or upsetting tool halves are mounted so as to be horizontally displaceable with respect to their carriers are and the lower clamping or upsetting tool halves by means of further links with an additional movable auxiliary crosshead are articulated, the auxiliary crosshead interchangeable spacers wearing.

Such a design of the forging device for crankshafts and the like The compression stroke for the displacement stroke can be changed as required, and the two settings for the compression stroke and the enforcement stroke are completely independent of each other. The angular position of the handlebars is in one very wide range freely selectable, as the clamping force is independent of the angle of the handlebars. Double lever do not come because the jaws are passed through the carrier and thus not out of their horizontal position can tilt. The forging press is universal in a larger dimension frame can be used without expensive and essential device parts having to be replaced. The additional Auxiliary crosshead makes it possible that by placing intermediate pieces of different heights on the auxiliary crosshead the size of the displacement stroke can be determined in a simple manner without the size the upsetting stroke is influenced. The sliding surfaces of the movable clamping jaws are only used by the Clamping force loaded while the force of the tool of the displacement beam and the vertical component the upsetting force absorbed by the toggle lever chants will. The dislocation force generated by the dislocation beam in connection with the others Steering the toggle linkage a horizontal component that increases the compression force, while the Vertical components cancel each other out. Meet the lower clamping cylinders of the clamping drive here a double function, namely the clamping of the workpiece during the upsetting process, and Furthermore, the size of the upsetting stroke can be determined with these by defining the initial angular position of the toggle linkage determine without affecting the size of the displacement stroke. Even the upper ones Clamping cylinders of the clamping drive fulfill a double function, namely the clamping of the workpiece during the upsetting process and in the holding down and clamping of the workpiece when pulling it out of the displacement tool. This also solves the withdrawal problem in a simple way, by the clamping jaws only releasing the workpiece after pulling out the displacement tool. at the execution of the cranking of the workpiece move the upper Verictzungswerkzeug and the lower translation tool in vertical direction. Here the upper translation tool performs a Stroke, which corresponds to the double path of the lower displacement tool. This translation tool is lowered by the path of the crank radius, while the upper displacement tool doubles Way covered this radius. As a result, the press ram path is doubled for a given uniform work given, which means halving the required pressing force.

The auxiliary crosshead is advantageously designed as a closed frame and is along vertical guides guided. The columns of the forging press can also act as vertical guides for the auxiliary crosshead hand over. The auxiliary crosshead can, however, also be arranged on independent vertical guides be. The intermediate pieces are expediently guided by means of the vertical guides or columns thereby secured in their position. The upper beams can have external stops for the upper ones Have clamping or upsetting tool halves, which is known per se (US Pat. No. 3,373,593).

The invention is explained below with reference to an embodiment shown in the drawing.

F i g. 1 shows an embodiment of the device according to the invention on a forging press in view, partly in section and in scheme;

F i g. 2 to 6 represent the forging press and the device of FIG. I in different phases of work represents, wherein the F i g. 1 to 4 the press with lowering of the press ram and F i g. 5 and 6 the forging press in illustrate two different phases of the retraction movement of the press ram;

F i g. 7 shows a side view of the forging press corresponding to the position of FIG. 4 schematically.

The forging press for forging crankshafts, etc., is a hydraulic four pillar press with the columns la ib. Lc, id and an upper yoke 2, which is firmly connected to the press ram (not shown), and with a lower Crosshead 3. which is firmly mounted on a press table (not shown). The upper crosshead 2 is slidably guided in a known manner along the columns la to id. The upper crosshead 2 has hydraulic cylinders 4a, \ b in which pistons 5a, 5b are hydraulically actuated, with which the carrier 6 for the tools is firmly connected. This carrier carries clamping and upsetting tool halves 7a, 7b, which can be displaced transversely with respect to the carrier 6. The displacement tool 8 is firmly connected to the crosshead 2. The displacement tool is advantageously arranged on the crosshead 2 such that it can be exchanged. The lower position of the carrier 6 isi by a (not shown) stroke limiter, ζ. Β a stop, set.

The lower fixed crosshead 3 also has cylinders 9a, 9b in which pistons 10, 10a are provided, with which the lower support 11 for the tool halves is fixedly connected. This carrier carries clamping and upsetting tool halves 12a and 12Ö which, like the upper tool halves, are mounted transversely on sliding surfaces 13. With the lower beam 11 is the lower part of the displacement tool

ges, d. H. the anvil 14, firmly connected, which can form one piece with the carrier 11.

On the pillars la, 16, lc, Id there is an auxiliary crosshead 15 Slidably mounted, the toggle linkage 16; i, 166 or 17.-ι, 176 with the lower fixed crosshead 3 communicates. The links 16./, 16b and 17; i, 176 of the toggle linkage are around a common Axis 18 and 19 mounted and jointly hinged in the lower clamping jaws 12 and 126. the upper handlebars 16a and 17a sinJ at 20 and 21 in the Auxiliary crosshead 15 and lower links 166 and 176 at 22 and 23 in the lower fixed crosshead 3 pivoted. With 24a and 246 spacers are referred to, which on the auxiliary crosshead 15 can be put on and graze expediently guided through the pillars. The spacers are Interchangeably arranged and can be replaced by other spacers of different heights.

Starting from the position of the parts of FIG. 1 is located the upper crosshead 2 is in its upper position, and the upper piston 5a. 56 of the clamping cylinder 4a, 46 are extended. The upper clamping jaws 7a, 76 rest on their stops 6c, 6c /, which are adjustable, z. B. by means of a slide guide od. Like. Can be arranged. The pistons 10a, 106 of the lower clamping cylinder 9a, 96 are also extended to a predetermined amount. The altitude of the lower beam 11 determined in cooperation with the Knichcbelgestänge 16a, 166: 17a, 176 both the horizontal and the vertical position of the lower clamping and Upsetting tool halves 12a, 126. In these is the to machining blank 25 is inserted, which already has a cranked part 25a. The starting position shown the lower clamping cylinder 9a, 10a; 96. 106 determines the size of the compression stroke.

Thereafter, the upper crosshead 2 is lowered by the press ram. The upper clamping and upsetting tool halves 7a, 76 engage in the lower clamping and upsetting tool halves 12. 126 in a form-fitting manner and clamp the workpiece 25 (Fig. 2).

By lowering the upper crosshead 2 further, the transfer tool 8 places itself on the workpiece 25 and begins to move on the middle clamped part of the workpiece 25. In addition sets the upper crosshead 2 on the intermediate pieces 24a, 246, which are attached to the upper links 16a, 17a of the toggle linkage attached auxiliary crosshead 15 are carried. It now becomes the auxiliary crosshead 15 taken along by the upper crosshead 2. wherein the auxiliary crosshead 15 in turn the toggle linkage 16a, 166; 17a, 176 actuated. As a result, the clamping and upsetting tool halves 7a, 12a and 76, 126 brought together against one another, the upper tool halves 7a, 76 by corresponding engagement are taken into the lower of the lower tool halves 12a, 126. In this way the upsetting stroke comes about, at the same time the entire cranking with the crank pin and the two Cheeks is generated. The start of the upsetting movement depends on the given position of the toggle linkage 16a. 166: 17a, 176 thus depends on the thickness of the intermediate pieces 24a, 246, while the size of the Upsetting stroke only from the position of the clamping cylinder 9a. 10a; 96. 106 is dependent. The size of the displacement stroke by means of the displacement tools 8, 14 is a function of the thickness of the intermediate pieces 24a. 246.

In Fig. 4 the position of the parts is illustrated, in which the press ram and thus the upper transverse

ao at all 2 have reached the lowest position. The pressing process is finished. The clamping and upsetting tool halves 7a, 12a and 76, 126 have approached the anvil 14. Now the lower clamping cylinders 9a. 10a, 96,106 relaxed.

The upper crosshead 2 then moves upwards and pulls the displacement tool 8 out of the newly polished Cranking of the crankshaft out, while the upper Kiemmzylindcr 4a, 5a, 46. 56 through Keep the workpiece clamped accordingly by regulating the hydraulic pressure. they seem at the same time as a hold-down device by holding the clamping jaws 7a, 76 in their lower position (FIG. 5).

Only after pulling out the welding tool 8 reach the upper clamping cylinders 4a. 5a, 46. 56 their end position. If the upper one continues to run up Crosshead 2, the upper tool halves 7a, 76 release the workpiece (FIG. 6).

The workpiece is now taken out of the forging press and after it has been warmed up, it can be manufactured a further crank crank in the forging press in the position of the parts according to FIG. I with corresponding Inserted offset, the tool halves 7a. 76 each to the outside of the stops 6c. 6d have been returned. The work cycle can then start again.

If the size of the clamping cylinder is suitable, the piston of the clamping cylinder can be used during the pressing process The displaced hydraulic fluid is fed to the press system in order to generate energy to a certain extent to win back.

In addition 7 sheets of drawings

721

Claims (4)

Patent claims: 1. Device for forging crankshafts, flange shafts, etc. by means of a forging press, in which a split relocation tool for producing a crank is arranged between separate upper and lower clamping tools and the carriers of the upper clamping and upsetting tool halves are mounted on a movable, upper crosshead and the supports of the lower clamping and upsetting tool halves are articulated to the stationary cross or foundation spar by means of a link, whereby the two tool halves come into positive engagement with each other in the clamping position and are driven jointly toggle-like under the action of the downward moving head in the axial direction of the workpiece for upsetting, characterized in that the carriers (6, 11) of the upper and lower clamping or upsetting tool halves (7a, 7b, 12a, 126) have a direct hydraulic clamping drive (4a, 5a and Ab, 5b as well as 9a, 10a and 9b, 106) that the upper and lower clamping or upsetting tool halves (7a, 7b, 12a, 126) are mounted horizontally displaceably with respect to their supports (6, 11) and the lower clamping or upsetting tool halves (12.3, t2b) are articulated to an additional movable auxiliary crosshead (15) by means of further links (16a, 17a) Auxiliary crosshead (15) carries interchangeable intermediate pieces (24a, 24b). 2. Apparatus according to claim 1, characterized in that the auxiliary crosshead (15) is designed as a closed frame and is guided along vertical guides, the columns (la, \ b, lc, Id) of the forging press can be used as vertical guides. 3. Apparatus according to claim 1 or 2, characterized in that the intermediate pieces (24a, 246) are guided by means of the vertical guides or columns and secured in their position. 4. Device according to one of claims 1 to 3, characterized in that the upper carrier (6) have external stops (6c, 6d) for the upper clamping or upsetting tool halves (7a, 7b) .