DE1145018B - High-speed hydraulic press, especially forging press or drawing press - Google Patents

Description

In hydraulic presses, e.g. B. forging presses or drawing presses, it is known to use the drive a z. B. make compressed air loaded high pressure accumulator and high pressure translator. At all known hydraulic high-pressure intensifiers, however, is the ratio of the primary pressure to the secondary pressure constant, equal to the ratio of the two piston areas. In addition, the speed with which a pressing stroke including relief can be carried out, not satisfactory. Drop forging presses and drawing presses, e.g. B. rubber drawing presses, are in the rest of the usual Way driven by a water-loaded high-pressure accumulator, dispensing with pressure intensifiers. In these presses in particular, there are difficulties in the pressing and relieving processes to be carried out in short times. In particular, hot workpieces, like titanium sheets, are not deformed, since the rubber cushions over the duration of the pressing and Relief processes cannot bear the temperatures and thereby heat themselves up too high and destroy them will.

It has therefore been proposed that the contact times between the hot workpiece be considerably shorter and the deformation tool, and therefore has to deform titanium workpieces, especially sheet metal, drop hammers are used. The efficiency of such drop hammers is bad, because a rubber block has to serve as a hammer for the sheets mentioned.

The invention has set itself the task of the pressing and relieving process of hydraulic Accelerate pressing without enlarging the high pressure accumulator in a disadvantageous manner or its Increase pressure intolerably.

The invention is used in high-speed hydraulic presses, in particular forging presses or drawing presses, e.g. B. rubber drawing presses, driven by a z. B. compressed air loaded high pressure accumulator and a high pressure intensifier. It consists in the fact that the high pressure intensifier consists of consists of driving and driven pistons, the driving and driven pistons are at an angle to each other move and are directly connected by a toggle system, drive through its extended position will.

In a further development, the invention consists in adapting the control of the pressing pressure that takes place in the high pressure intensifier via the pressing away to the pressure characteristics of the pressing process, whereby a high-speed hydraulic press,
in particular forging press or drawing press

Applicant:
G. Siempelkamp & Co., Krefeld, Ritterstrasse

Mathias Schmid, Krefeld,
has been named as the inventor

Further energy savings are possible, as this setting results in a pressure rise with a similar characteristic can be done as needed in the press

ao, and the energy used is thus limited to what is absolutely necessary. To z. B. regardless of the die height and die depth or other conditions of the pressing process in the case of the invention hydraulic presses to get by with a single high-pressure intensifier suggests the invention provides that the pressure increase in the Hochdrack booster through a pressure relief valve is limited. The pressure relief valve can be assigned to the driving pistons or their cylinders be. In particular, it is advisable to make the device as a whole in such a way that two driving pistons of the high-pressure booster mounted coaxially in two cylinders, connected to one another by a rigid piston rod connected and to this piston rod the toggle rods of two driven pistons with the first are arranged at right angles to the direction of movement. This embodiment is in the simplest way a variable translation between driving pistons, driven pistons and thus a variable Pressure translation achieved in such a way that the driven piston at the beginning of their movement only a small and theoretically an infinitely large hydraulic one at the dead center of the drive linkage Can generate pressure, the delivery rate in relation to the path of the driving piston in the reverse Relation stands as the pressures. This makes it easy to see that the last described The pressure intensifier generates hydraulic pressure with a similar characteristic that increases as it does in die presses and in particular, rubber pad presses are required according to the deformation conditions of the workpieces will.

309 538/248

Claims (5)

In hydraulic presses according to the invention it is possible in the dead center of the drive linkage 13 a, 13 b theoim rest, the plunger and thus retically an infinitely large hydraulic pressure, the driven piston of the intensifier can generate with oil, the delivery rate in relation to to drive, whereas the driving Piston the path of the driving piston 11 a, 11 b in the reverse pressure booster and the high pressure accumulator 5 th ratio is as the pressures. From this it recognizes that water can be fed. that the hydraulic generated by the intensifier The advantages achieved by the invention are lische pressure in a similar characteristic grows as mainly to be seen in the fact that it is needed with hydraulic he in die presses (see. Druckver-Pressen is possible, the actual pressing process in the running sketch of Fig. 2). to lead extremely short times, even if io A press stroke is z. B. executed by Bewees are large presses. For example, with the drive joint 14, the toggle rods, it is possible to move the press in a few seconds up to \ 2> a, 13 b from point α to point b, while the movement of this point from b to c by touching the dies with the rubber block close the press and then relax again in a second or two. Here you get to carry out the pressing process in point b and to do the complete 15 a moderate high hydraulic pressure in the Zy retraction in a few more seconds. relieve the driven piston 12 ″, 12 b. Since this Another significant ¹ advantage is that pressure in dead center, that is imfPunkt b, infinitely large by the high-pressure accumulator forth considerable energy _se in may whose absolute value is saved by one, as more fully below safety valve 15 limits . As the amount of is explained. Finally, in the erfindungsgemä- 20 applied dies 2 will be different and SEN hydraulic press, the hydraulic working pressure _SO with the working stroke of the plunger in the cylinder 4 can always be substantially increased in the press, which also varies, it could happen that z. B. allowed with smaller press dimensions and with direct low dies and small required Ar press drive from Akjsp was previously not possible. bitshub is the maximum pressure at any point The invention at hand is a would be required between α and b 25, only one exemplary embodiment illustrative drawings u _m the high-pressure intensifier 10 is not unnecessarily large explained. It shows need to build is achieved through valve 15, Fig. 1 in a schematic representation of a system that the maximum pressure can always be generated at point b according to the invention umL. The valve 15 is used for this purpose Fig. 2 is a pressure curve sketch of the Drucküberset- 3 ° by the pressure in one of the two cylinders of the zers. Pistons 12 a, 12 b of the high pressure booster 10 so The illustrated in Fig. 1 rubber cushion drawing press 1 controls that it drains pressing fluid when the hydraubesitzt in the usual way a fixed die 2 and a pressure in the drive cylinder should be larger rubber block 3 as a counter-die. The operation of the z. B. the coming from the high pressure accumulator press takes place via the press piston 4 and requires 35 mende drive pressure minus 10%>. This 10% difference in relation to the press itself, not referring to the details, is used to overcome the flow explanation. For the hydraulic drive of the press resistances from the high pressure accumulator to a known, loaded with compressed air water drive cylinder of the high pressure booster 10. As accumulator 5 is available. The closing stroke, which can be seen from the drawing, the deformation press 1 takes place with low pressure, which is taken from a pressure intensifier driven by the work in the press and its relaxation up to the accumulator. Closing pressure is generated by the driving pressure being generated. This pressure intensifier has a small ben the pressure intensifier is driven from α to c . High pressure piston 6α ,, which with 300 atm acted upon this way, a changeover of the drive liquid Schlagt If, and a large low-pressure piston 6 b, ness at the point of highest pressure, as in which the closing, ie to raise the overall 45 available type of hydraulic presses generated the case weight required hydraulic pressure. is avoided. Since the speed of the driving The working speed of this pressure booster 6 piston by using the accumulator drive can be controlled almost arbitrarily by appropriately large control valves 7 and since each switchover can be set up as quickly as desired. The low pressure generated here in this area of the pressing cycle is able to close the press. 50, this arrangement is the only possibility until the material to be deformed 8, which is on the part of such a large press, is actually solid Lower die 2 lies, touches rubber block 3. lent pressing and relaxation process in the shortest possible time. The next pressing cycle is switched automatically to the second pressure booster 10, which, when fed from the accumulator, rather generates the high pressure required for pressing from the second opposite drive cylinder. where the driving piston or the toggle lever This high-pressure booster has two driving rod pivot point 14 migrating from c to α. 11a, Ub, and two driven pistons 12 a, 12 b. the
driving piston ll'e, b 11 fed from the high-pressure accumulator 5 and move the perpendicular 60 CLAIMS: arranged to driven piston 12 a, 12 b via two toggle rods 13 α, 13 b, the extended position of which is 1st high-speed hydraulic press, ins- is driven through. The drawing shows that special forging press or drawing press, with in the selected power transmission from the driving drive via a z. B. high- Piston to the driven piston a variable 65 pressure accumulator and a high pressure over-transmission in such a way that the driven setter, characterized in that the high piston 12a, 126 at the beginning of their movement only pressure transducer (10) from driving ( 11a, 11b) one can generate small pressure while it and driven piston (12 a, 12 b) consists of the driving and driven pistons (11 a, 11 6 or 12 a, 126) move at an angle to each other and are directly connected by a toggle system (13 α, 13 b) , the extended position of which is passed. 2. Hydraulic press according to claim 1, characterized in that to adapt the Pressing pressure to the pressure characteristics required to deform the workpiece (8) Pressure translation between high pressure accumulator pressure and press pressure in the high pressure intensifier (10) is mutable. 3. Hydraulic press according to claims 1 and 2, characterized in that the pressure increase limited in the high pressure booster (10) by a pressure relief valve (15) and thereby is adaptable to the drawing or pressing depth. 4. Hydraulic press according to claims 1 to 3, characterized in that the pressure relief valve (15) the driving piston (11a, 116) of the high pressure booster silO) or their Cylinder is assigned. 5. Hydraulic press according to claims 1 to 4, characterized in that two driving pistons (11 α, 116) of the high pressure booster (10) mounted coaxially in two cylinders, connected to one another by a rigid piston rod and to this the toggle rods (13 a, 13 b) two driven pistons (12a, 126) are arranged with the direction of movement at an angle to the first. Considered publications:
German patent specifications No. 47 229, 261719,
510; German patent application H 8583 Ib / 58 a (published 11/6/1952);
U.S. Patent No. 1927 085;
"Journal of the Iron and Steel Institute",
February 1951, p. 185;
"La Machine Moderne", February 1956, pp. 57 to 59. 1 sheet of drawings