Patent Application
20110302980
WO 2009/146715 A1 discloses a bush expander in which a punched bush blank can be slipped over a forging mandrel, which is internally coolable by a coolant, can be mounted onto support rollers and, following intermittent rotation of the bush blank about its longitudinal axis, can be deformed on its outer side, in portions, by at least one laterally disposed forming tool, which is intermittently drivable by motorized means, for example hydraulically, said bush blank being supported internally on the forging mandrel. With the previously known bush expander, bush blanks having unit weights of many hundreds of tonnes, for example between 200 and 600 tonnes, preferably around 400 tonnes, a diameter of 3000 to 10 000 mm, preferably 8000 mm, and overall heights of one to nine meters, preferably three to six meters overall height, are able to be machined and forged on the outer side by partial shaping. The bush blank over the flanging mandrel is here mounted onto support rollers by means of a crane. Following closure of the platen, the partial forging is then commenced. After each stroke, centering rollers push the bush blank somewhat away from the flanging mandrel and further rotate the bush blank by a small angular measure in its longitudinal axis, before the next forging stroke is executed. The mandrel is rotated by the same angle. To this end, laser measuring systems move the centering rollers into the correct working position. The cyclical alternation in the course of the forging, and thus the partial forging, should be realized at very high speed, for example between 30 and 90 strokes, preferably between 40 and 60 strokes per minute. Conical blanks can also be widened into cylindrical bushes, while the height of the bush can also be increased.
It is also known to use large ring-rolling mills. The investment costs for these are very high. In the case of relatively small numbers, the investment in such ring-rolling mills often does not pay. The bush cannot be lengthened. On the inside, in the middle, the structure is unacceptable.
DE 31 26 120 A1 discloses a turntable-type manipulator on ring-forging presses having a horizontal forging press with forging mandrel, for use in the production of rings or bushes. No further information is given about the press itself.
EP 0 524 815 A shows a device which can be inserted into a vertical press. The hydraulic energy is redirected to the horizontal cylinders of the device in order then to expand the bush.
DE 24 20 921 A1 is not suitable for partial forging in order to influence the degree of forging of the structure, remedy conicities and profile the bush.
DE 24 34 587 A1 discloses a machine for expanding forged ring blanks.
The object of the invention is to provide a charging device for a bush expander, which allows very precise positioning of the respective punched bush blank and thus precise and flexible shaping/forging of the bush blank.
A further object of the invention is to provide a method for forging extremely large and heavy bush blanks.
The object is achieved by virtue of each of the coordinate patent claims 1 to 4.
A charging device according to the invention can be operated independently of the actual bush expander or forging press and thus in a flexible manner. The charging device takes up the weight of the bush blank, transports it into the forging press, and out of the same, and also has bearing pedestals having preferably three, mutually spaced supporting means, which are vertically movable in a reciprocating motion in opposite directions and are rotatable, in both cases, respectively, by motorized means. The movement and thus actuation of these supporting means is incorporated in a CNC system, as well as all drives of the forming tool or tools and of the charging device, so that programmed, very precise working is possible. As a result of the preferably three, mutually spaced supporting means, a very precise adjustment of the bush blank, where necessary after each forging stroke, can be obtained by the CNC system, so that precise forging with narrow tolerances is possible with great accuracy in the peripheral direction and/or in the direction of the longitudinal axis of the forging stroke.
Much the same applies also to the approach according to patent claim 2, wherein the supporting means constitute cylinders and pistons of a piston-cylinder unit, which are drivable by a pressure medium, in particular by a hydraulic pressure medium, and which are movable independently of each other in a reciprocating motion, where necessary, however, also simultaneously in synchronization, in a CNC-controlled manner.
It is particularly advantageous if, in the basic solution as described also in patent claim 3, the supporting means and their motorized drives can be driven in a rotationally movable manner. The bush blank is thereby able to be rotated by the supporting means by a specific angular measure in its peripheral direction. The supporting means can then be lowered, so that the bush blank comes to rest upon appropriate bearing projections, walls or the like. The supporting means can then be back-rotated by a certain angular amount and are then extended to raise the bush blank, so that, after the next forging operation, the bush blank, where necessary, can once again be further rotated by a certain angular measure, and so on.
Patent claim 4 describes eccentric drives for the supporting means, based on basically the same solution process.
Further inventive embodiments are described in patent claims 5 to 16.
The charging device according to patent claim 5 allows a stable, yet precise alignment of the bush blank.
In the embodiment according to patent claim 6, strip-like and parallelly arranged supporting walls are provided on both sides of one of the reciprocating supporting means, while two further bearing pedestals arranged in corner points of a triangle are disposed next to strip-shaped supporting walls. These supporting walls serve to receive the bush blank after the supporting means have been lowered in order to, for example, back-rotate the supporting means by a certain angular measure.
It is particularly advantageous if, according to patent claim 7, the periphery of the bush blank is surveyed by at least two measuring devices in order to align the bush blank precisely to the supporting means, in particular to precisely determine its vertical position, to enable an optimally precise forging to be realized in the desired manner. The measurement values are electrically incorporated as signals in a CNC system and the drives of the supporting means are actuated correspondingly. The measurement values can also be used, however, to actuate the forging tool or tools so that, for example, wall regions of different thickness are deformed with correspondingly greater frequency or with correspondingly greater energy.
In addition, an embodiment according to patent claim 8 is particularly advantageous. The charging device is here configured as a trolley and runs on wheels or rollers, which can be arranged such that they are transportable in a forcibly guided manner, in particular on rails. This enables the bush blanks to be driven correspondingly easily into the forging device, but also removed from this again so as to be fed, for example, to a furnace, in which, after a certain forging time, they are further heated.
According to patent claim 9, the laser measuring devices are arranged scattered by an acute angle, preferably by an angle of 90 degrees, over the periphery of the bush blank and record measurement values in the vertical direction at the bush blank, which measurement values are relayed to the CNC system. This allows precise vertical alignment of the bush blank to the supporting means.
In the embodiment according to patent claim 10, the forging mandrel, by means of a crane, is inserted into the punched hole of the bush blank, and also withdrawn again therefrom and transported away. In the insertion process, the forging mandrel is placed by means of hydraulic lead-in cylinders downward onto a bearing and centered.
Advantageously, the centerpoints of the supporting means lie in the corner points of an isosceles triangle—patent claim 11, while the centerpoints of the lift cylinders of the supporting means, in the embodiment according to patent claim 12, are arranged in the corner points of an equilateral triangle.
In addition, it is particularly advantageous that, in the embodiment according to patent claim 13, the lift cylinders of the supporting means are controlled in such a way by the CNC system that they adjust their horizontal position by motorized means in accordance with the growth in the diameter of the bush blank, so that the bush blank is always securely and reliably supported and maintains its exact vertical position.
According to patent claim 14, the supporting means, in particular three supporting means, operate with their support surfaces or support points as a translatory walking beam system, in which the stroke can be preselected on a continuously variable basis via the CNC system. The corresponding signals can be filed in the software of the CNC system.
In addition, it is particularly advantageous that, according to patent claim 15, the support surfaces or support points of the supporting means are freely movable in the horizontal direction, so as to automatically return the bush blank into the correct position after each forging stroke. The actuation of the drives of the supporting means which is necessary for this purpose can be performed by the CNC system.
In the embodiment according to patent claim 16, the end face position of the forging blank is registered by the alignment leveling of the lift cylinders.
This object is achieved by virtue of each of patent claims 17 to 20.
The method according to the invention allows a very precise and efficient forging of punched bush blanks, in particular the reduction of setup times and dead times in the charging operation.
Further inventive embodiments are described in patent claims 21 to 24.
The advantageous characteristics and effects deriving from these claims emerge from the following description of the drawing, in which the invention is illustrated—partly schematically—by way of example, wherein:
In the drawing, the invention is represented applied to a bush expander, configured as a forging press, bearing the reference symbol 1.
By means of a trolley-like charging device, denoted in its entirety by the reference symbol 2, the bush expander can be fed a bush blank 3, which can also, however, be transported back out of the bush expander 1.
The bush blank 3 can consist of steel, for example, and is fed to the bush expander 1 at a forging temperature of over 1200° C., in the case of steel, and remains in the bush expander 1 for a certain period, for example one to two hours, and is then returned by the charging device 2 to a furnace, for example, where it is reheated to the forging temperature. Other bush blanks 3 can meanwhile be heated in other furnaces, which other bush blanks are alternately fed by means of trolley-like charging devices 2 to the same bush expander 1 or to a plurality or multiplicity of bush expanders 1, which are arranged side by side or one behind the other in the same building or in other buildings.
Not just one, but also a plurality of trolley-like charging devices 2 can therefore be provided for one and the same bush expander 1 or for a plurality of bush expanders 1 (not represented).
In the represented embodiment, the bush blank 3 is configured such that it is cylindrically or conically offset or profiled on the inside and the outside, and thus on the inside possesses a pervasive punched hole 4 (shown in idealized representation in the drawing), which can also deviate more or less strongly from the cylindrical form in the initial stage and into which a forging mandrel 5 can be inserted from above by means of a crane or other manipulator (not represented), which forging mandrel at the top and bottom is locked in place and held in centered arrangement by appropriate bearings 6 and 7 or platens. The forging mandrel 5 has a longitudinal channel 8 passing through it, through which the coolant, in particular cooling water, is conveyed by a pump (not represented).
At 9 is represented a die block, which, by means of suitable, for example hydraulically operated drives 10 and 11, is driven in the direction X, Y, i.e. onto the periphery of the bush blank 3 and deforms the latter correspondingly. In the drawing, only one forging tool or forming tool, configured as a die block 9, is represented. However, a plurality of such forging tools 9 can also be arranged one above the other and/or side by side in the peripheral direction of the bush blank 3, which forging tools are driven jointly or alternately on an intermittent basis by the drives 10 and 11 and appropriately deform and forge the bush blank 3 correspondingly. Both the bush blank 3 and, preferably, the forging mandrel 5 are arranged such that they can be rotated, where necessary, about their longitudinal axis and can also be shifted in the X or Y direction and locked in place in the longitudinal axis.
The drives 10 and 11 can be configured as hydraulic drives, which can be driven alternately on both sides, in a controlled manner, by a suitable pressure medium, in particular by a hydraulic pressure medium.
A frame or a base for the bush expander configured as a forging press is denoted by 12, which frame or base rests firmly on a suitable further base, for example made of swing concrete, concrete or the like (not represented).
The trolley-like charging device 2 has a plurality or a multiplicity of wheels or rollers 13, of which, on both sides of the charging device, a plurality of wheel sets are arranged at a distance apart with their axles one behind the other in the direction X or Y, so that the trolley-like charging device 2 can carry and convey large bush blanks of, for example, 200 to 800 tonnes, preferably 200 to 600 tonnes starting weight, in the state heated to forging temperature. The wheel sets or wheels 13 can be arranged in a forcibly guided manner (not represented) on rails, which are laid in the factory building floor (likewise not represented) or on beams.
As can be seen from the drawing, in particular from
These supporting walls 16 and 17 are adjoined by offset supporting walls 21 and 22, which are likewise configured as workpiece holders and the upward-facing surfaces of which likewise lie in a same horizontal plane, the longitudinal axes 19, 20 of these supporting walls 21 and respectively forming an acute angle α and β with the longitudinal axis 15 of the trolley-like charging device 2. The upward-facing end faces of the supporting walls 21 and 22 configured as a support structure lie in the same horizontal plane and can be disposed in the same horizontal plane as the upper end faces of the supporting walls 16 and 17.
Arranged between the supporting walls 16 and 17 serving as a workpiece holder is a rail guide 23, 24, which serves for the longitudinal and forcible guidance of a supporting means 25, which is arranged such that it can be shifted by a motor drive 26 in the direction of the longitudinal axis 15 of the trolley-shaped charging device 2 and locked in place. This motor drive 26 is in the present case configured as a workpiece positioning and linear cylinder and consists of a piston-cylinder unit, the piston of which can be acted upon alternately on both sides, in a controlled manner, by a suitable pressure medium, for example hydraulically, from a hydraulic source (not represented).
To the supporting means 25 there is likewise assigned a piston-cylinder unit, which is vertically movable in a reciprocating motion, hence in opposite directions, and can also be locked in place in the respectively desired stroke position. This piston-cylinder unit is likewise acted upon alternately on both sides by a suitable pressure medium, in particular by means of hydraulic fluid. The pressure medium is delivered from a pressure medium source (also not represented), for example by a pump set (likewise not represented). Power is supplied via power cable carriers (not represented).
In addition, the supporting means 25 is provided with a motorized rotary or pivot drive 27, which is connected to a rotary and receiving slide 28 and, in the case of an eccentric drive 29, is articulately coupled by a hinge joint 30 to an eccentric lever 31.
At 32 is provided a motor drive for the trolley-shaped charging device 2, which motor drive in the present case is likewise configured as a piston-cylinder unit, the piston of which can be acted upon alternately on both sides by suitable pressure medium, especially by hydraulic pressure, from a suitable pressure medium source, in order to transport the charging device 2 in the direction X or Y and also lock it in place in the respectively desired position.
Instead of a piston-cylinder unit for the motor drive 32, other suitable motor drives, for example a suitable linear motor, a spindle drive or the like, may also be considered.
As can be seen particularly clearly from
The supporting means 33 and 34 are respectively disposed, like the supporting means 25, on a rotary and receiving slide 54 and 55 and are respectively linearly displaceable via a respective motor drive 43 and 44 and are also adjustable into the respectively desired position. The motor drives 43 and 44 are configured, just like the motor drive 26, as workpiece positioning cylinders, to which motor drives are respectively assigned pistons, which can be acted upon, alternately on both sides, by pressure medium pressure, in particular hydraulic pressure, in order to displace the slides and lock them in place in the desired position. These adjustment tasks can be sensitively performed.
With reference to
As can be seen, in particular, from
The motor drive 26, which is configured as a workpiece positioning and linear cylinder, also has a position measuring system 46 of this type, by means of which the adjustment travel of the rotary and receiving slide 28 is able to be measured and determined. To the respective supporting means, or, more precisely, to the piston-cylinder unit configured as a trolley receiving and adjusting cylinder, is assigned an eccentric 47, to which there is assigned the eccentric lever 31, which, via the hinge joint 30 and the motor drive 27, is respectively swiveled in the direction A or B, whereby the trolley-receiving and adjusting cylinder is pivoted by maximally 45° to both sides of the longitudinal axis 48. As already mentioned, the two other supporting means 33 and 34 are of the same construction, i.e. possess the same eccentric drives, piston-cylinder units, motor drives and position measuring systems, like the position measuring systems 45 and 46.
As is apparent from
Furthermore, to the bush expander are assigned, in the represented embodiment, two laser measuring systems 52 and 53, which are offset by 90° in the peripheral direction of the bush blank 3 and which are connected to the switch cabinets, and thus to the CNC system, by electric leads (merely indicated). All motor drives, hence including the motor drives of the supporting means 25, 33, 34, of the measuring systems, and the laser measuring systems 52, 53 and the drives 10 and 11, are incorporated in the CNC system, so that a program control of the entire motional sequence, inclusive of the shaping or forging operation, is able to be obtained. The lasers are scanning lasers, which can scan the whole of the bush contour. In the drawing, only two scanning lasers, mutually offset by 90°, are represented. Further scanning lasers for measuring position, profile, ovality and wall thickness are not represented.
Illustrative Procedure:
Depositing of the heated bush blank 3 on the trolley-like charging device 1.
A crane inserts the forging mandrel 5 into the bush blank 3, whereupon the forging mandrel 5 is locked in place.
The laser measuring systems record the position of the bush blank 3 and correct it by appropriate actuation of the motor drives of the supporting means 25, 33, 34 and/or of the drive of the trolley-shaped charging device 2.
After a certain time, the locking mechanism of the forging mandrel 5 is removed, the forging mandrel 5 is lifted out by a crane, and the not yet fully shaped bush blank 3 is heated in a furnace back up to forging temperature, while a previously heated bush blank 3 is loaded on a provided charging device 1. A plurality of bush expanders 1, which interact with numerous furnaces, can be parallelly in use.
The pressure in the water-oil emulsion for the drive of the forming tool can measure 250 bar to 650 bar.
The features described in the abstract, in the patent claims and in the description, as well as those which are apparent from the drawing, can be fundamental to the realization of the invention, both individually and in optional combinations.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20 2010 009 094.6 | Jun 2010 | DE | national |
