EP0621093B1 - Press line comprising a transfer device for transferring workpieces - Google Patents

Description

The invention relates to a Press line or large part step press with one Transport device to Transporting workpieces according to the generic term of claim 1.

State of the art:

A press line consists of a series of individual presses, their type and number through the range of parts to be produced is determined.

A large-part step press is in principle a special case a press line and exists depending on the desired Number of stages from individual presses, via the press stands too are joined together in a fixed bond and by an in Drive direction driven drive shaft driven will.

Both for press lines and for large part step presses can the workpieces, for example sheet metal parts, from   Processing level to processing level using crossbeams are transported at right angles to the transport direction arranged and stored at their ends in trolleys are. The trolleys are at two in Direction of transport or press longitudinal axis Carrier rails can be moved in and against the transport direction stored (DE 38 24 058 C1). In the known facilities the trolleys are in the direction of transport extending push rods connected to each other. By Moving in and against the transport direction is the Carried out step. The lifting and lowering movement of the Crossbeams are lifted and lowered by lifting them together Carrier rail itself executed. To change the location of the Workpieces are generally between the Work stages an empty stage in which the workpiece is temporarily stored (see DE 41 04 810 A1).

It has become known from DE 38 43 975 A1, a Change the position of the workpieces in that the Crossbeams can be rotated with respect to their longitudinal axis be, with the rotary motion also common powered swivel lever system from a cam mechanism he follows.

As can be seen from DE 41 04 810 A1, such Transport equipment has the disadvantage that per stage two part-specific cross members are required, which a maximum of half a transport step from the respective processing station to the intermediate one Carry out blank and back, one intermediate resting position for the crossbars can be provided. These crossbars must be used Tool change with the sliding tables from the press be pulled out and replaced.  

The establishment of its own orientation station, Intermediate station or empty stage between the individual Processing stations for clipboard and execution a change in position naturally also has the disadvantage that the support templates there also depend on the parts and are also exchanged when changing tools have to.

Since the empty stages or orientation stations in general Area of the press stands are arranged, it is still required to change the parts-related accessories of these orientation stations on the side of the sliding tables Clearances are required to replace the parts to be able to stake on it. Both the orientation stations as well as the additional space to the side of the sliding tables however, occupies a work space, which is the distance of the Work stages and thus the overall length z. B. one Large part step press enlarged. The enlargement of the Distance of the work stages has the additional disadvantage that long distances have to be driven with the workpieces, what It takes time and energy.

Finally, the prior art can also be disadvantageous Number of complex and inflexible curves for Implementation of the parts transport control, being large Weights of push rods and mounting rails and others moveable units overcoming large mass forces required.

Another is from GB-A-2 243 134 Press line with a transport device for transporting workpieces become known in which the workpieces by means of fixed longitudinal rails  

Crossbeams to the individual processing stations be transported. With this transport device additional dolly or sledges on the by the Press leading transport rails provided, by means of which the crossbeams move relative to each other can perform at least two degrees of freedom. Hereby are compensation steps only for part adjustment performed. The movement of the Crossbeams are only relative to each other educated.

From the generic US-A-5,140,839 is a press line with a Transport device for transporting workpieces became known in which the Workpieces are attached to cross members, which by means of independently operable means of transport to the individual processing stations can be transported. over a transfer device consisting of an articulated chain the crossbeams can each independently of one is transported to the next processing stage, whereby the transport step is determined by the link chain is.

Object of the invention:

The invention has for its object the above disadvantages described in the prior art as possible avoid and especially one Press line or large part step press with one Transport device too create which with high economy and extreme   Flexibility can work. Thereby the Transport device regardless of the design of a press with successive processing stations.

This task is based on a press line of the introductory type according to the invention by the Features of claim 1 solved.

In the subclaims are useful and advantageous Further developments and improvements of the press line or large-part step press specified according to the main claim.

Advantages of the invention:

The invention Avoids press line or large part step press first the disadvantages mentioned above. The invention lies there the core idea is that universal mobility both the crossbeams for admission, change of position and Transport of workpieces as well as flexible mobility the press ram can be achieved. This is especially true even if the individual press stages are independent work from each other.

A universal mobility of the workpiece receiving and transporting crossbar achieved according to the invention in particular that everyone Crossbeam at least one dolly or Transport carriage is assigned which has its own drive allowed in at least two degrees of freedom, where in particular a horizontal movement of the trolley in and against the transport direction as well as a vertical movement of the trolley for up and down movement of the Crossbeam is provided. Here are these Transport movements can be controlled individually for each crossbeam, so that a drive that is completely independent of time and place   each crossbeam made within the press assembly can be. Of course, the movements of the Processing stages, d. H. e.g. B. the up and down movement of the press ram and the movements of the associated, on Trolleys arranged cross beams on top of each other be coordinated and synchronized by what higher-level control for the part-specific process of Transport trolley and the press control can be done. A programmable drive for the dolly is therefore included the press control synchronized.

According to the invention, the transport device can also be a Have rotating device to rotate the Crossbar around its longitudinal axis and thus one Carry out additional swiveling movement of the workpiece can. This is particularly the case with spatially complicated Workpieces are an advantage. With very simple workpieces this possibility of movement may not apply.

By different lifting movements of two, at the ends a crossbar arranged trolley can Requires a desired cross-beam inclination can be set. This results in two more Degrees of freedom of movement.

Due to the mobility of the crossbeams in several Degrees of freedom with the trolley are unnecessary separate orientation stations between the individual Press stages or processing stations. Rather, it can Workpiece of the adjustable in different directions Crossbeam from one processing station in one determined position by a vertical upward movement removed and by means of a horizontal, full Transport step to the next processing stage transported and aligned accordingly.  

In this next processing station, the workpiece is then with a vertical downward movement exactly new positioned filed. This eliminates the complicated Orientation of the workpiece in a between the Orientation station lying processing stations. Everyone Transport trolley is therefore with three different possible Drives fitted to the crossbar in three Degrees of freedom, d. H. a longitudinal movement, a Vertical movement and a rotary movement around the longitudinal axis the crossbar to be able to perform. The additional Inclination of the crossbar leads to another Degree of freedom.

The pivoting movement of the workpiece by means of a rotary drive the crossbeam also serves in particular to change one Oblique position in the tool when entering and removing the Workpiece to have better freedom of movement over the To achieve the upper tool.

Usually the crossbars are made up of two lateral transport car of the type described above held. The trolleys are expediently on two mounting rails arranged in the longitudinal axis of the press run and at least two processing stages each connect. The mounting rails can go through the entire press run in one piece. Conveniently, the DIN rails using a separate drive Height-adjustable to accommodate tool changes to lie above the stored upper tool and thus to allow the tool set to be moved out. Before can the cross members by moving above the Tool set to be staked out on this.

According to the press ram one after the other following processing stages out of phase with each other   work. That means that a subsequent plunger e.g. B. moves up later than the previous one. Through the individual drive of each of the processing stations assigned cross-beam carriage can such phase-shifted movement of the press rams with a equally phase-shifted movement of the crossbeams be coordinated. This allows the Distance of the crossbeams when removing or entering from the or become smaller in the tool than z. B. the   The distance between the tool stages itself corresponds. The additional Time saved through this phase-shifted movement for loading and unloading the workpieces in the Machining stations corresponds to the angular offset of the Phase shift of the ram or the trolley. This creates a better one in particular Free movement to the upper tool. Finally, through the phase-shifted run of the individual press rams one possibly provided common coupling chosen smaller become, because basically not all plungers to the same Are at the bottom dead center.

When changing tools, the upper tool is placed on the Lower tool driven and detached from the ram. Subsequently the ram is moved to the top dead center position and the Support rails are with the car and the crossbars booted. It is - as mentioned - advantageous if the crossbars moved laterally over the tools and staked on this, d. H. from the dolly be uncoupled. The cars are in the Stand area moved and the mounting rails as far up driven that the sliding tables with the tools and unplugged cross members from the press. It is also advantageous if the cross members at Can be swiveled to the side when changing over to create additional space and to change tools facilitate.

The invention further provides that the entry of Blanks in the first processing station also by means of a crossbar can be made. Because of several Degrees of freedom on the dolly can also be greater Transport steps are carried out, for example, the System to a larger spider or gripper to adapt this area.  

Further details and advantages of the invention are known from the Drawings can be seen and in the description below an embodiment shown.

Fig. 1

einen Schnitt nach der Linie A-A in Fig. 5 in einer ersten Pressenstellung,

Fig. 2

einen gleichen Schnitt in Fig. 5 in einer anderen Pressenstellung,

Fig. 3

einen Schnitt nach der Linie B-B in Fig. 6,

Fig. 4

einen Schnitt nach der Linie F-F in Fig. 7,

Fig. 5

einen Schnitt nach der Linie C-C in Fig. 2,

Fig. 6

einen Schnitt nach der Linie D-D in Fig. 3,

Fig. 7

einen Schnitt nach der Linie E-E in Fig. 4 sowie

Fig. 8

ein Bewegungsschaubild.

Show it

Fig. 1

5 shows a section along the line AA in FIG. 5 in a first press position,

Fig. 2

5 shows the same section in another press position,

Fig. 3

6 shows a section along the line BB in FIG. 6,

Fig. 4

7 shows a section along the line FF in FIG. 7,

Fig. 5

3 shows a section along the line CC in FIG. 2,

Fig. 6

4 shows a section along the line DD in FIG. 3,

Fig. 7

a section along the line EE in Fig. 4 and

Fig. 8

a motion diagram.

Description of an embodiment:

In Figures 1 to 4 in side view, and Fig. 5 to 7 in front view is a press line, a large part step press or a press group in general in different editing settings. Of the The press assembly initially consists of headers 1 to 4 as well as the respective press stands 9 one behind the other, 9a to 13, 13a. The press stands are on the Press tables 5 to 8 on which the sliding tables 14 to   17 are arranged. In the press group are still shown the press rams 18 to 21 with associated Upper tools 26 to 29 with the lower tools 22 to 25 interact.

In the longitudinal direction through the individual presses or the Press assembly are mounting rails 31, 31a in height-adjustable slide 30, 30a mounted, which in turn are guided in vertical guides 63, 63a to 67, 67a (Fig. 5). Transport trolleys 32, 32a in and against the transport direction of the workpieces slidably guided. The transport trolleys 32, 32a have in turn vertical guides 33, 33a on which Carriages 34, 34a are vertically displaceably mounted (see Fig. 5). The carriages 34, 34a have pivotable receptacles 35, 35a, in which the crossbars 37 to 41 can be inserted are attached (Fig. 5). The crossbeams are with Transport elements 80, e.g. B. sucker or magnetic elements equipped on which a board 42 or the workpieces 43rd up to 47 can be transported through the press stages.

The drive of the trolley 32, 32a takes place via z. B. programmable electric drives or the like, the Drive is synchronized with the press control. Furthermore, the drive of the trolleys 32, 32a for the Crossbeams 37 to 41 electric motors in connection with Pinions, racks or toothed belt pulleys with toothed belts respectively. As an alternative, a linear motor drive be provided. Finally, the drive of the Transport trolleys 32, 32a also mechanically from the individual presses controlled, whereby cam gears, levers, spline shafts, Toothed belts and racks or the like can be provided can.  

With a higher-level control of the press system Part-specific travel paths of the trolleys specified will.

When changing tools, the cross beams 37 to 41 are open Stake out pins 48, 48a to 52, 52a preferably for placing or removing the tools on the Sliding tables 14 to 17 as shown in dashed lines in Fig. 3 also laterally in an approximately horizontal position can be pivoted away. The swinging away takes place outside or to the side of the press or tool set. In another embodiment as shown in FIG. 4 the crossbars 37 to 41 on the upper tool attached brackets 53, 53a to 57, 57a staked and can remain assigned to the tool set.

The energy supply for the drives of the trolleys 32, 32a takes place via a cable drag chain 58, 58a to 62, 62a (see Fig. 2 or 4).

Figures 1 and 2 show press rams 18 to 21, the work out of phase with each other. This is with the arrows 93 shown. In this case, the plunger 18 hurries to the plunger in FIG. 1 19 a little ahead, while the plunger 20 straight in the lower Dead center lingers and the plunger 21 a downward movement carries out. In this phase, the trolleys 32, 32a be arranged outside the processing room, they can but are already moving in this direction. After the Tappet 18 in Fig. 1 first moved up, the First approach the first transport trolley with cross-beam 37 and the board 42 from the board feed belt to the first Lead processing station 5 (Fig. 2). During this phase the press ram 18 can already move downwards (see arrow 93 in Fig. 2). Alike the second crossbar 38 takes over the workpiece from the first processing station 5 and transfers this with a   full work step taking advantage of the necessary Degrees of freedom of movement to the second processing station 6. The other cross members 39 to 41 work analogously, whereby the phase shift of the movement of the Press rams 18 to 21 alike from the dolly 32, 32a of the individual cross members. This results in a considerable saving of time.

8 are the time-shifted Strokes of the press rams 18 to 21 with the curves 84 to 87 and the horizontal movement of the cross members 38, 39 with the Curves 88, 89 shown. The is on the X axis Crank angle o or time t and the path s on the Y axis applied. The distance between the top and bottom Boundary lines 91, 92 represent the step distance or the Transport step between the processing stations 5, 6. The center line 90 corresponds to half the step spacing Parking or waiting positions 94 shown there for the Transport trolleys 32, 32a.

The curve section 70 shows the retraction of the crossbar 38 into the tool 22 to remove the workpiece 43. in the Curve section 71, the workpiece in the tool 23 on Press ram 19 transported. In the curve section 72 drives the crossbar 38 back out of the tool 23 out and is when the plunger 19 reaches point 73 is in waiting position 94 between the processing stations 5, 6, d. H. from the collision area with the associated one Tool upper parts 26, 27. To measure 74 (offset of the lower or top dead center UT, OT) are the press rams 18 to 21 out of phase with each other. To the same phase shift as the press rams 18 to 21 the cross members 37 to 41 run out of phase to each other, z. B. the crossbar 38 in Transport step 71 the cross member 39 by the dimension 75   catches up. This measure must be smaller than the measure of Step distance minus the sheet metal part width.

The invention is not based on that shown and described Embodiment limited. Rather, it includes everyone professional training and development within the framework of the inventive idea. In particular, the Invention in both a mechanical and a hydraulic press.

Claims (9)

1. A press line or multiple-die press for large pressings, with a conveyor means for transporting workpieces, with serially disposed working stations for the workpiece, in which upwardly and downwardly movable rams with tools for reshaping the workpieces are disposed, the workpieces being mounted on cross-members which can be transported to the working stations by means of independently operable transport means, characterised in that associated with each cross-member (37 to 41) there is on both sides a transport carriage (32, 32a) comprising drives in a plurality of degrees of freedom and independent of other transport carriages on other cross-members, whereby in order to carry out any desired workpiece transport step in and against the direction of workpiece transport there is a longitudinal drive and also a lifting drive for performing a vertical lifting movement of the cross-member and preferably a rotary drive for carrying out a rotary movement of the longitudinal axis of the cross-member and in that both the press rams (18 to 21) and also the transport carries (32, 32a) for the cross-members (37 to 41) are adapted for movement towards one another, the latter with phase displacement.
2. A press line or multiple-die press for large pressings, according to claim 1, characterised in that the lifting drive for the transport carriages (32, 32a) of a cross-member (37 to 41) can be variously loaded in order to achieve a desired sloping attitude of the cross-member.
3. A press line or multiple-die press for large pressings according to claim 1 or 2, characterised in that programmable drives synchronised with the press are provided to drive the transport carriage (32, 32a).
4. A press line or multiple-die press for large pressings according to one of the preceding claims, characterised in that the drive of a hydraulic press ram (18 to 21) and/or the transport carriages (32, 32a) for the cross-members (37 to 41) is provided by means of an overriding control arrangement in order to achieve part-specific movement distances of the transport carriages.
5. A press line or multiple-die press for large pressings according to one of the preceding claims 1 to 4, characterised in that the drive of the transport carriages (32, 32a) for the cross-members (37 to 41) is provided by means of electric motors, pinions, racks or toothed belt pulleys.
6. A press line or multiple-die press for large pressings according to one of the preceding claims 1 to 4, characterised in that the drive of the transport carriages (32, 32a) for the cross-members (37 to 41) is provided by linear motors.
7. A press line or multiple-die press for large pressings according to one or more of the preceding claims, characterised in that the drive of the transport carriages (32, 32a) for the cross-members (37 to 41) is controlled mechanically by the individual presses by means of cam transmissions, levers, splined shafts, toothed belts and racks or the like.
8. A press line or multiple-die press for large pressings according to one or more of the preceding claims, characterised in that the transport carriages (32, 32a) for the cross-members (37 to 41) are guided on supporting rails (31, 31a) which are guided through the press or press line.
9. A press line or multiple-die press for large pressings according to one or more of the preceding claims, characterised in that the supporting rails (31, 31a) are adapted for vertical adjustment by separate lifting means with vertically adjustable slideways (30, 30a) as well as guides (63 to 67 and 63a to 67a).