US3824833A

US3824833A - Forging press

Info

Publication number: US3824833A
Application number: US00330194A
Authority: US
Inventors: H Bachmann
Original assignee: Langenstein and Schemann GmbH
Current assignee: Langenstein and Schemann GmbH
Priority date: 1972-02-07
Filing date: 1973-02-07
Publication date: 1974-07-23
Anticipated expiration: 1991-07-23
Also published as: JPS4890958A; FR2171268B1; JPS571339B2; FR2171268A1; GB1409979A; IT978844B

Abstract

A forging press in which there is provided a press frame, a table plate, a ram above the table plate, a working space defined between the table plate and the ram, at least one die situated on the table plate, and pincers and grippers for holding a workpiece, with the pincers or grippers being carried by an extremity of a handling arm or lever and being movable over and away from the or each die.

Description

United States Patent Bachmann July 23, 1974 FORGING PRESS [56] References Cited [75] Inventor: Horst Bachmann, Rodental, UNITED STATES PATENTS Germany 1,387,260 8/l92l Hand 72/361 [731 Assignw Lansenmin & Schema 3331553 131132 2,11 .13: IIIIIffiIIIIf'5'1Z/ 1 B Akt'engeseuschan Cobulgt 3,135,397 6/1964 Kull 214 1 BC Germany [22] Filed: Feb. 7, 1973 Primary ExaminerRichard J. l-lerbst [2]] Appl No: 330,194 Attorney, Agent, or firm-Holman & Stern 30 F A D [,57] ABSTRACT orelgn pplcatlon 'nomy am A forging press in which there is provided a press Feb. 7, 1972 Germany 2205607 frame, a table plate a ram above the table plate, a Feb. ,7, 1972 Germany 2205608 working Space defined between the table plate and the ram, at least one die situated on the table plate, and 52 US. Cl...., 72/3 1, 72/427, 113/113, pincers and grippers for holding a workpiece, with the Int Cl B 9 pincers or grippers being carried by an extremity of l a b T T [58] Field of Search 72/344, 345, 361, 422, a mg or ever emg 6 over, an

away from the or each die.

4 Claims, 7 Drawing Figures RENEE- {824,833 sum 8 0F 7 Fig 6 Pmmmwtz wn 3.824.833 swarm? H oQ F ORGING PRESS BACKGROUND OF THE INVENTION The invention relates to a forging press conprising a press frame, at least one die, a table plate and a work ing space.

In one aspect, the invention provides a forging press comprising a handling system, in which press several dies are arranged on a stationary rectangular table plate which is situated on a press frame and opposite to a single ram or hammer and above which is present a working space, with two opposite sidesof the table plate being clear of the press frame so that a workpiece can be passed through the working space, the handling system including a pair of pincers or grippers arranged on one extremity of a handling arm, another extremity of which is situated outside the working space, with 1 said one extremity being movable into or out of the working space and above the dies.

PRIOR TECHNIQUES In one embodiment of a forging press of this nature, the dies are arranged on a straight line which is parallel to a central horizontal axis of the press and extends in the direction in which the workpiece passes through the working space. The grippers are equally displaceare situated at a relatively great distance from the center of the table plate.

The dies should be situated as close to the center of the press however, to minimize tilting of the ram during the deforming operation. This is of importance because ever greater workpiece precision is required in processing technology ln the case of hand-fed presses it is customary, therefore, to position the dies as close as possible to the center of the press. The pattern of the dies is then irregular. a v

In the case of a handling arm carrying a pair of grippers at one extremity, it is possible to arrange its other extremity in pivotable manner around a pivot spindle situated outside the working space within which the grippers are displaceable. The pivot axis is horizontally arranged, however, since a workpiece should be turned in such manner that its underside is positioned at the top, or vice versa. The displacement of the workpiece from one die to the next is performed by parallel displacement of the handling arm. It is disadvantageous that one pair of grippers with a co-ordinated actuating system is incorporated for each die in this press. Moreover, 'all the dies are situated on a common straight line.

A variety of forging presses comprising handling systems incorporating pincers or grippers are known. The manner in which the systems employed for actuation and displacement of the pincers or grippers or of banable along a straight line and merely serve for conveying a workpiece from the outside of theworking space dling levers carrying the pincers or grippers are to be devised is thus known in principle moreover.

OBJECTS AND SUMMARY OF THE INVENTION table plate and allows a workpiece to be passed through the working space, and in which press the table plate may beutilized in optimum manner, on the one hand, meaning that a maximum proportion of the table surface may be covered by dies and in which the dies are situated as close as possible to the center of the press, and on the other hand, the workpiece may be passed through the working space entirely by means of the handling system. Moreover, the handling system should not impede accessto the dies, and conjointly with its entraining mechanisms, it should be arranged independently of the press and as far as possible outside the working space, i.e., the deforming space.

In one aspect, the invention provides a forging press wherein a pivot spindle aroundwhich the handling lever is pivotable, is arranged vertically outside the working space beside the imaginary extension of the working space, with the dies concomitantly being positioned along an are about the pivot spindle and the straight line connecting two of the dies in each case s'ubtendin'g an angle with the twohorizontal axes of the press, and at the other side of the table plate from the aforesaid pivot spindle, a second pivot spindle aroung which a second handling lever bearing grippers is pivot- In a forging press of this kind, each of the grippers may not only be pivoted into and out of the working space for infeed or removal of a workpiece, but is also displaceable within the working space over at least two dies. Each of the grippers penetrates into the working space at the side of the latter which is opposed to the pivot spindle of the handling lever and may be displaced up to close to the side of the working space which is adjacent to the pivot spindle, with the pivot spindle as well as the entraining mechanisms being situated as close to the press frame as possible but not in front of the working space. I

To this end, one of the two grippers, or one of the handling levers, is employed to feed a workpiece into the working space, and the other gripper or the other handling lever is employed to withdraw the workpiece after deformation. The invention renders it possible to position three or more dies particularly close to the center of the press, e.g., three dies forming a triangle being incorporated. The transfer of the workpiece from one of the grippers into or to the other occurs at the point of intersection of the arcuate trajectories of the two grippers, which may coincide at the center of one least one die arranged on a table plate above which is present a working space, is situated opposite to a ram in a press frame, and pincers or grippers di splaceable above the die and away from the latter arearranged on one extremity of a handling lever. 1

In one embodiment of a forging press of this kind, the handling lever merely serves the purpose of carrying a blank relatively short workpiece into the working space and to a first die the blank workpiece being relatively short. If the handling lever is employed to convey a relatively long workpiece from one die to the next or out of the working space, the long workpiece should initially be moved out of the die in an upward direction, in a lengthwise direction.

This may be performed by employing an ejector rod in a commonly known manner, which rod is arranged beneath the table plate together with a hydraulic ejection system andejects the workpiece from the die in the v upward direction. To this end, the ejector rod or the hydraulic ejection system should be of appropriate length such. that the forging press has considerable structural depth below the table plate. It is an object of the invention to devisea forging press wherein a long workpiece may not only be conveyed by means of the handling system towards and away from the die but also out of the die, so that a reduction in the overall height of the forging press may be obtained.

In a preferred aspect, the invention provides a forging press wherein the handling lever is upwardly and downwardly di'splaceable and can be releasably cou pled to the ram.

, In a forging press of this nature, the grippers grasp a projecting portion of a long workpiece which is preponderantly inserted'into the die. After the deformation it hasundergone within the die, the workpiece may either still project a little in an upward direction, or it may have been pushed upwards through a short distance after the deforming action, by means of a short ejector rod. Once the grippers have secured a grip on the workpiece, the handling lever is coupled to the lowered ram The releasable coupling of the handling lever may be performed in different ways. It is particularly preferred, however, for a catch plunger co-ordinated with the 'die and comprising an approximately horizontal detent step to be arranged to project in downward direction on the ram, and for a pivotable'pawl which may be positioned over the detent step when the ram is lowered and the grippers are positioned above the die, to be arranged on the handling lever. 7

One catch plunger is arranged on the ram for each die from which a long tightly fitting workpiece is to be withdrawn. When the grippers arranged on the handling lever have secured a grip on the workpiece present in the die and the ram has been moved downwards, the pawl is pivoted over the detent step and secured thereat, so that the upwardly displaced ram can draw the workpiece out of the die.

The displaceability in the upward and downward direction of the handling lever whichis always displaced parallel to itself while being moved up and down, may also be established in appropriate manner according to requirements. It is particularly appropriate, however, for the extremity of the handling lever opposed to that of the grippers to be displaceable upwards and downwards outside the working space, along a stay which rotatable around a central vertical axis.

To'this end, the mechanisms for thepivoting of the rod may be stationarily arranged, so that they do not which is then moved upwards, thereby drawing the work-piece out of the die. The handling lever is then disconnected from the ram, so that the workpiece may be handled, i.e., displaced by means of the handling lever. Forces occurring uponwithdrawal of the workpiece do not produce bending stresses along the length of the handling lever.

The connection between the grippers or handling lever and the ram is advantageous in the case of particularly long workpieces which are jammed very firmly in the die after deformation, because it precludes considerable structural complexity in the press. Several ejector bars are required moreover, if several dies are arranged within the press platform or table plate, in the case of known presses. The ejector bars are supported on an ejector stage which is arranged below-the table plate and is moved up and down by means of a subjacent ejector cylinder. In the case of very long workpieces, e.g., in the case of long-stemmed rear axle shafts for commercial vehicles, the structural length of the press frame below the press table wouldbecome particularly great as a consequence of the relatively long ejection path. The foundations would, moreover, have to have recesses of corresponding depth in view of the downwardly projecting ejector cylinder. All this may be eliminated by the invention.

accompany the upwards and downward displacements of the handling lever. The stay itself is rotatably journalled, to allow of turning the handling lever. The upward and downward displacement of the handling'lever is performed by means of a hydraulic system, for example.

Forging presses embodying the invention are illustrated in the accompanying drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a horizontal cross-section through a vertical forging press;

FIG. 2 shows a side view of part of the forging press shown inFIG. l;

FIG. 3 shows a plan view of handling lever and per of the forging press shown in FIG. .1;

FIG. 4 shows a diagrammatic plan view of another forging press; 9

FIG. 5 shows a partially sectioned plan view of another forging press;

FIG. 6 shows a side view of the forging press shown in FIG. 5; and

FIG. 7 shows a side view of a mechanism for releasable connection of the handling arm or lever or of the grippers arranged thereon to a ram of the press shown in FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION The forging press shown in FIG. 1 comprises a table plate or press plate 1, whichis stationarily arranged, i.e., the table plate 1 is not displaced for the purpose of repositioning a workpiece. The table plate 1 is approximately rectangular, with each of the shorter sides having a length greater than three-quarters of the length of each of the longer sides. Two spaced columns 2 of a press frame are arranged at opposite sides of the table plate 1. The columns 2 comprise guiding bars 3 for a ram or press carriage (not shown in FIG. 1), which can be moved up and down above the table plate 1. The

' two sides of the table plate 1 which are at right angles to the sides at which the columns 2 are arranged, are unobstructed i.e., not covered by the press frame, so that a workpiece can be passed through a working space4 present above the table 1. Two horizontal press axes 5, 6 at right angles to each other and intersecting at the center of the table plate 1 maybe allocated to the press as a whole.

At the same side from the horizontal press axis 6,

being the left side in FIG. 1, are two

vertical pivot spindles

7, 7 which are situated directly opposite to each other at either side of the press axis 5 and closely beside one of the'two columns 2 but outside an working space 4 and beside the imaginary extension 8 of the working space. Around each of the

pivot spindles

7,7 can be turned a

handling lever

9,9 which bears a pair of

grippers

10,10 at its free extremity. The centers of the grippers 10,10'are displaceable' along an

arc

11,11 about the

pivot spindles

7,7. Thetwo arcs 11, 11 intersect each other on the press axis 5 at a distance from the center of the table plate 1.

The extension of each of the handling levers 9,9 into the working space 4 is bent so that the

pivot spindles

7,7 may be situated close to the columns 2. The two grippers 10, may then be pivoted into and out of the working space in each case. FIG. 1 shows the grippers 10 outside the working space in dash-dotted illustrated 10". Each pair of grippers has two

movable jaws

12,13 and a piston-cylinder system 14 for actuation of the jaws. The centers of four deforming stations are situated on the arcs11,11. The front handling lever 9' carries a workpiece from the outside, into the working space 4 and to a first deforming station 15 which is situated close to the edge of the table plate 1. The front handling lever 9 also carries the workpiece from the first deforming station, at which is situated, for example, a rough-forming tool, to a second deforming station 16, at which is situated, for example a roughing mandrel tool, and from the latter to a third deforming station 17, at which is situated, for example an extrusion molding tool. Therear handling lever 9 carries the workpiece from the third deforming station 17 to a fourth deforming station 18 at which is situated, for example a sizing tool, and from the latter to the working space.

Three points of impingement are incorporated, since the rear grippers 10 should impinge at three different positions. One of the impingement points consists of a single hydraulic damper 32, whereas the others consist of a piston-cylinder system 33 comrpising hydraulic dampers. Four impingement points formed by hydraulic dampers on piston-cylinder systems 34,35 are informed by means of a piston-cylinder system 23 (see FIG. 2) which acts on the one hand-on a stationary block 24 and on'the other hand on -a projection 25 joined to the handling lever close to the pivot spindle -7. The handling lever 9 is installed'at the bottom on a cylindrical unit 26 which may be displaced up and down on two vertical spaced rods '27. Eachrod 27 is secured at the top and bottom in a circularplate which is not shown. One of the circular plates is rotatably arranged at the top in the block 24, and the other circular plate is arranged in a block 28. The position of the two

blocks

24, 28 is apparent from 'FIG. 2. Beneath the lower block 28 is situated a piston-cylinder system 29 whereof the piston rod, not illustrated, projects upwards through the lower block 28 for pushing the handling lever 9' upwards.

The front handling lever 9 comprising the grippers 10', but not the rear handling lever 9, is shown in FIG. 2. A ram 30 whereof the underside carries upper tools 31 situated at the deforming stations referred to above. Lower tools are fastened on thetable plate 1 at the deforming stations. Beneath the table plate 1 is situated an ejector mechanism which is known per se and not shown in detail, which mechanism comprises ejector rods whereby it is possible to lifta workpiece at least so far out of the die at each deforming station, that the grippers can secure a grip. Since the grippers may be moved up and down, even very long workpieces may be withdrawn upwards from the dies while gripped by the grippers.

As shown in FIG. 3, both

jaws

12, 13 of the grippers 10 or pincers are displaceably arranged. Displacement of the

jaws

12,13 is performed by means of a pistoncylinder system 14 which is situated in the handling lever 9 or in the grippers 10. The system whereby the piston-cylinder system 14 and the

jaws

12,13 cooperate, is illustrated in detail in FIG. 2..

The forging presses shown in FIG. 4 and 1 have a bent handling lever at the front as well as at the rear. The rear handling lever 9 is constructed and arranged symmetrically with respect to the front handling lever 9. Thus the

pivot spindles

7,7 are precisely aligned opposite to each other and the

grippers

10,10 are precisely aligned opposite to each other for identical positioning of the handling levers. The arcs 11,11 along which the

grippers

10,10 are displaced, intersect each other on the horizontal press axis 5, the position of the point of intersection of the arcs depending on the length of the handling lever and on the positioning of the

pivot spindles

7,7. The transfer of the workpiece from one pair of grippers to the other occurs at the point of intersection.

As shown in FIG. 4, the centers of four deforming stations are situated on each of the

arcs

11,11. A deforming station 15, for an initial forming operation, e.g., upsetting, a deforming station 16 for a second roughing operation, e.g. rough drifting, a deforming station .17 for a second rough-forming operation, for example drifting (punching or spreading), and a transfer station 21 at which a piercing operation is performed, are situated on the are 11. On the other are 11 are situated a deforming station 18 for a trimming operation, a deforming station 19 for a first extrusion molding operation, a deforming station 20 for a second extrusion molding operation, and the transfer station 21.

The two deforming

station

15 and 18 are a relatively great distance from the center of the table plate, whereas the other deforming stations are situated as close as possible to the center of the table plate and have their centers situated on a common circle 22, with the center of the transfer station 21 being situated at the center of the table plate.

In the forging press shown in FIG. 4, seven operations may be performed on the table plate 1, the workpiece being handled by two grippers only. The front grippers 10 carry the workpiece into the working space 4 to the first deforming station 15, from the latter while by passing the third deforming station 17 and the transfer station 21 to the second deforming station 16, from the latter to the third deforming station 17 and then to the transfer station 21. The transfer station 21 is situated at the point of intersection of the

arcs

11,11 and is utilized for a deforming operation as well as for the transfer of the workpiece from the front infeed grippers to the rear grippers 10'. The latter remove the workpiece from the transfer station 21 and carry the same to the fourth deforming station 19, from the latter and while bypassing the transfer station 21, to the fifth deforming station 20. From the latter, the workpiece is carried to the sixth deforming station 18 and from this latter out of the working space 4 to an extraction station.

The forging press shown in FIG. 5-, comprises a table plate or press plate 101, which is stationarily arranged, i.e., the table plate 101 is not'moved for re-positioning a workpiece. The table plate 101 is approximately rectangular, each of the shorter sides having a length greater than three-quarters of the length of each of the longer sides. Two columns 102 of a press frame are situated on opposite sides of the table plate 101. The columns 102 comprise guiding bars 103 for a ram 131 or press carriage shown in FIG. 6, which can be moved up and down above the table plate. The two sides of the table plate 101 which extend at right angles to the sides occupied by the columns102 are unobstructed, i.e., are clear of the press frame, so that a workpiece can be passed through a working space 104 present above the table plate 101. Two press axes 105,106which intersect at the center of the table plate and extend at right angles to each other may be allocated to the press as a whole.

A heated blank workpiece 108 may be carried into the working space 104, i.e., on to the table plate 101 and thereon to a first deforming'station 109,1at which the blank workpiece is subjected to arough forming operation. The blank workpiece 108 is then carried from the first'deforming station 109 to a second deforming station 110 at which is situated a die wherein an extrusion molding operation is performed. A third deforming station 11 at which is situated a die'wherein the workpiece which has been extrusion molded at the second deformingv station 110, is exposed to finishpressing operation, is also situated on the table plate 101.

To carry the workpiece from the second deforming station 110 to the third deforming station 111 and from the latter and out of the working space to a distributing station 112 constructed as a rotary plate and situated in front of the press, a handling lever 113 comprising grippers 114, is provided. The centers of the second deforming station 110, the third deforming station 111 and the distributing station 112 are situated on a common are 115 along which the grippers 114 are displaceable. So that the grippers 114 may carry the workpiece away from the second deforming station or third deforming station, said workpiece is pulled upwards out of the dies situated at these deforming stations. To this end, it is pushed upwards a little by means of a short ejector (not shown) situated beneath the table plate 101.

The are 115 extends around a vertical pivot spindle 116 which is situated in front of the press frame, beside the imaginary extension of the working space 104 shown by dashdotted lines 117, and beside one of the columns 102, that is to say not within-the imaginary extension 117 of the working space. The extremity of the handling lever 113 opposite to that of the grippers 114 is pivotably journalled around the pivot spindle 116. The pivoting lever 113 has a bend 118 so that it enflanks the column 102 beside which is situated the pivot spindle 116, when the grippers 114' have been pivoted completely intothe working space 104. It is apparent that if the handling lever were straight, it would not be possible to pivot the grippers as far into the working space and that the handling lever would have to be shorter than in the case of a bent handling lever, for displacement into and out of the working space.

I The turning of the handling lever l 13 is performed by means of a piston-cylinder system 119 which acts through joints on a block 120 on the one hand, and on a projection 121 joined to the handling lever close to the pivot spindle 116, on the other hand. The grippers 114 comprise a jaw 122 rigidly joined to the handling lever 113, and a jaw 123 articulated on the handling lever 114. The displacement of these jaws 123 is performed by means of mechanisms not shown in detail, which are situated in the grippers 114 and/or in the handling lever 113. A stop 124 is provided, which determines the position at which the handling lever has been fully inserted by pivoting into the working space.

No special feed mechanism is provided. The handling lever 113 is employed to feed the blank workpiece 108 to the first deforming station 109 which, for this purpose, is situated close to the front edge of thetable plate 101 and whereof the center is situated on the are described by the grippers 114. The first deforming station at which a rough forming operation only is performed,'may be situated at a relatively great distance from the press center, i.e., from the point of intersection of the press axes 105, 106, since no particular precision is'required during the rough forming operation and no great forces are applied.

FIG. 6 shows further details'of the handling system shown in FIG. 5. The handling lever 133 is arranged at the bottom on a cylindrical unit 126 which may be displacedup and down on two vertical spaced rods 127. The rods 127 are secured at the top and bottom in a circular plate in each case, which is not shown. One of the cirular plates is rotatably journalled in the block and the other circular plate is arranged in another block 128. The position of the two blocks 120,128 is apparent from FIG. 6. Beneath the lower block 128 is situated a piston-cylinder system 129 whereof the piston rod, which is not shown, projects upwards through the lower block 128 and upwardly displaces the bandling lever 113 upon being extended.

The sequence of operations of the forging press shown in FIGS. 5 to ,7 is as follows:

As shown in F IG. 5, a blank workpiece 108' is laid on a pivotable plate 130 which is then turned clockwise through approximately 120 so that the blank workpiece reaches the distributing station 112. At the latter, it is grasped by the grippers 114 situated on the bandling lever which concomitantly occupies the position 113'. The blank workpiece is then carried to the first deforming station in the working space 104, at which it is deformed, e.g. upset, by lowering the ram 131 which carries upper tools, after the grippers have been pivoted out of the working space.

The ram 131 is then moved upwards again, so that the workpiece may be carried from the first deforming station 109 to the second deforming station 110 by means of the grippers 114. After the grippers have been pivoted into the working space again, the ram is lowered and deforms the workpiece at the second deforming station by an extrusion molding operation. After the ram has been moved upwards again, the grippers carry the extrusion-molded workpiece from the second deforming station 110 to the third deforming station 111 and are then pivoted out of the working space. The ram then moves downwards, again, therebyfinish-pressing the workpiece, and subsequently moves upwards again. The grippers may then carry the finished workpiece from the third deforming station 111 out of the working space, to the distributing station 112 and on to the plate 130 on which it is conveyed further by rotation through 120.

If the grippers 114 are to convey the workpieces which had been deformed in the second deforming station 110 or in the third deforming station 111, the

workpieces must first be lifted upwards out of the dies It is appropriate in this connection, in the case of long workpieces in particular, to employ ejectors known per se for the sole purpose of lifting the workpiece out of the die so far only that the grippers can secure a grip, and the further extraction of the workpiece from the die being performed by upward displacement of the grippers. The handling lever 113 is concomitantly exposed to considerable stresses, especially if considerable friction prevails between the workpiece and the die, since the grippers project to a relatively great distance from the guiding points-on the rods 127. These stresses are eliminated if the handling lever 113 or the grippers 114 is or are coupled-to the ram 131,-sothat the upwardly displaced ram pulls the workpieceout of the die.

As shown inFlG. 7, a shackle 132 whereon a projection 133 is pivotable around a horizontal axis, is arranged on the grippers 114. A piston-cylinder system 134 has one extremity jointedly coupledto theprojection 133 and the other jointedly coupled to the handling lever 113 and may displace the projectionback and forth between a position in which it points vertically upwards and a position in which itis horizontal.

A catch plunger 135 which comprises a detent step 136 and projects downwards, is situatedon the ram 131. When the projection 133 has been pivoted upwards, the catch plunger 135 or the ram maybe moved downwards in such manner that the projection may be pivoted into the horizontal position over the detent step 136. If the ram 131 is then moved upwards, it pulls the grippers 114 upwardslt is also possible on the other hand, to pivot the grippers 114 into the working space, for horizontal setting of the projection 133 and a position of such nature of the catch plunger 135 or of the detent step 136, that the projection is pushed overthe detent step upon being pivoted inwards. The catch plunger 135 is arranged in each case on the ram beside an upper tool which is co-ordinated with a die for production of long workpieces.

In the example shown in the drawings, a catch plunger is coordinated only with the deforming station 110, since a greater tractive force can be expected only upon withdrawal of the xtrusion-molded part. By contrast, the finishpressed workpiece may be pulled out of the deforming station 111 bythe handling lever itself.

The piston-cylinder system 134 acts an an overload safety device moreover. if a predetermined permissible force is exceeded, e. g. during extraction, the projection 133 is displaced upwards against the resistance of the piston-cylinder system 134 and is thus freed automati: cally from the ram 131. The permissible force may be set in an infinitely variable manner by means of hydraulic setting elements. A description of the functional sequence for the extraction of long workpieces by means of the handling grippers in combination with the ram is given below.

After the workpiece has been inserted into the lower tool 110 by the handling grippers, the extrusionmolding operation is initiated. The ram concomitantly moves downwards rapidly, performs the pressing action and moves upwards through a definite stroke distance. Simultaneously with its upward displacement, the ejector situated beneath the table 101 pushes the piece upwards by the corresponding stroke length. The grippers are then pivoted from position 112 to position 110 at which they are coupled with the ram. As soon as the grippers have been coupled with the ram, the ram moves to its upper terminal position and concomitantly wholly pulls the workpiece held in the handling grippers out of the lower extrusion-molding die.

When the ram has reached its upper position, the grippers are uncoupled from the ram again, are pivoted over the die 111 and insert the workpiece into the die 111 into which the grippers are lowered. The grippers are thereupon pivoted to position 112 again and the finish-pressing operation is performed. After the finishpressing operation, i.e., after the ram has reached its upper terminal position again and the workpiece has been pushed partially out of the lower die by the ejector, the grippers are pivoted over the. die 111 again and pull the finish-forged part wholly out of the die without coupling .with the ram, and carry the same to the distributing station 112.

I claim:

1. A forging press comprising a press frame; a table plate; a ram above the table plate; the ram and the table plate defining aworking space therebetween; a die situated on the table plate; a handling lever; and grippers for holding a workpiece, the grippers being carried by an extremity of the handling lever and being movable over. and away from the die whereby a workpiece gripped by the grippers can be moved to a position over the die and forged between the die and the ram; the

table plate being stationary and rectangular, two opposite sides of the table plate being unobstructed by the press frame so that a workpiece can be passed through the working space, and the press further comprising: further dies situated on the table plate; a first vertical pivot spindle around which the handling lever is pivotable, the spindle being situated outside the working space and beside an imaginary extension of the working space, some of the dies being situated on an arc about the pivot spindle, above which are the grippers move when the handling lever is pivoted about the pivot spindle; a second vertical pivot spindle situated outside the working space and beside an imaginary extension of the working space, the second pivot spindle being adjacent the side of the table opposite the first pivot spindle; a second handling lever pivotable about the second pivot spindle; further grippers for holding a workpiece and carried by an extremity of the second handling lever, some of the dies being situated on an are about the second pivot spindle, above which are the further grippers move when the second handling lever is pivoted about the second pivot spindle, and the two said arcs intersecting.

2. The forging press according to claim 1, wherein an extension of each handling lever is bent in a direction into the working space.

3. A forging press provided with means for handling long workpieces, including a press frame; a table plate; a ram; an upper tool provided on the ram; a die situated on .the table plate opposite the upper tool and above which is a working space; a handling lever; and grippers which can be moved over and away from the die; said grippers being mounted at one end of the handling lever; a stay outside the working space; the end of the handling lever remote from the grippers being displaceable up and down outside the working space on the stay; a lifting device for displacing the end of the handling lever up and down; the upper tool and the die being situated at an extrusion molding station constituting one of several deforming stations and being designed to be suitable for extrusion molding; anda detachable mechanical connection provided between the handling lever and the ram in the working space at the extrusion molding station.

4. The forging press as claimed in claim 3 in which an overload safety device is provided for the mechanical connection between the handling lever and the ram wherein a piston cylinder unit operably coupled to the handling lever engages on a pivotable nose which can be positioned above a detent stop carried by the ram.

Claims

1. A forging press comprising a press frame; a table plate; a ram above the table plate; the ram and the table plate defining a working space therebetween; a die situated on the table plate; a handling lever; and grippers for holding a workpiece, the grippers being carried by an extremity of the handling lever and being movable over and away from the die whereby a workpiece gripped by the grippers can be moved to a position over the die and forged between the die and the ram; the table plate being stationary and rectangular, two opposite sides of the table plate being unobstructed by the press frame so that a workpiece can be passed through the working space, and the press further comprising: further dies situated on the table plate; a first vertical pivot spindle around which the handling lever is pivotable, the spindle being situated outside the working space and beside an imaginary extension of the working space, some of the dies being situated on an arc about the pivot spindle, above which arc the grippers move when the handling lever is pivoted about the pivot spindle; a second vertical pivot spindle situated outside the working space and beside an imaginary extension of the working space, the second pivot spindle being adjacent the side of the table opposite the first pivot spindle; a second handling lever pivotable about the second pivot spindle; further grippers for holding a workpiece and carried by an extremity of the second handling lever, some of the dies being situated on an arc about the second pivot spindle, above which arc the further grippers move when the second handling lever is pivoted about the second pivot spindle, and the two said arcs intersecting.

3. A forging press provided with means for handling long workpieces, including a press frame; a table plate; a ram; an upper tool provided on the ram; a die situated on the table plate opposite the upper tool and above which is a working space; a handling lever; and grippers which can be moved over and away from the die; said grippers being mounted at one end of the handling lever; a stay outside the working space; the end of the handling lever remote from the grippers being displaceable up and down outside the working space on the stay; a lifting device foR displacing the end of the handling lever up and down; the upper tool and the die being situated at an extrusion molding station constituting one of several deforming stations and being designed to be suitable for extrusion molding; and a detachable mechanical connection provided between the handling lever and the ram in the working space at the extrusion molding station.