EP3417178A1

EP3417178A1 - Synchronizing cylinder for extrusion plants

Info

Publication number: EP3417178A1
Application number: EP17702621.8A
Authority: EP
Inventors: Hermann-Josef Klingen; Uwe Muschalik; Ekhard Siemer; Karl Herrmann CLAASEN; Valentin Gala Losada; Andreas WERSHOFEN-CROMBACH
Original assignee: SMS Group GmbH
Current assignee: SMS Group GmbH
Priority date: 2016-02-16
Filing date: 2017-02-01
Publication date: 2018-12-26
Anticipated expiration: 2037-02-01
Also published as: CN108603521A; WO2017140499A1; KR20180098346A; KR102166035B1; JP2019511681A; JP6851388B2; EP3417178B1; DE102016214767A1; CN108603521B; US10670052B2; ES2880351T3; US20190017522A1; TW201738010A

Abstract

The invention relates to a synchronizing cylinder (1), preferably for an extrusion plant, comprising an outer cylinder (10), an inner cylinder (20) accommodated therein and arranged concentrically thereto, a double-acting working piston (41) that is displaceably provided in the inner cylinder, and a bypass device (50) having a bypass valve (52). The working piston (41) subdivides the inner cylinder (20) into two pressure chambers (42) and can be acted upon by both pressure chambers (42) with a hydraulic fluid. The bypass device (50) is designed such that in a bypass position of the bypass valve (52), a fluid connection between the two pressure chambers (42) is established via a direct connection, preferably at least one bypass line, and in a working position of the bypass valve (52), no such fluid connection exists.

Description

Synchronous cylinder for extrusion presses

Technical area

The invention relates to a synchronous cylinder, preferably for use in a forming device, in particular pressing system, extruder or ring rolling mill.

Background of the invention

Extrusion and ring rolling plants are devices for the plastic deformation of materials, such as preheated heavy or light metal blocks, by means of a targeted application of force. Thus, in the case of an extrusion press about such a heavy or light metal block, also referred to as a bolt, driven by a hydraulically operated ram through a so-called die, whereby a semifinished product is produced with a specific, defined profile. Such

Extrusion plants are known for example from DE 38 36 702 C1 and DE 10 2012 009 182 A1.

In addition to the actual application of force for forming the workpiece, such systems typically have drives for moving or positioning the

Transducer with the die or other equipment components on. Conventionally, the billet is configured by hydraulic cylinders over large strokes and brought into position. Thus, for example, the pickup is moved in this way between a position for block change and a front end position, the working position at which the sealing or pressing, airing and stripping is done. Alternatively, electric motors are used, which move the pickup between the block change position and the working position. In the case of the use of electric motors internal forces of the hydraulic cylinders are overcome. This applies in particular to the use of constant velocity cylinders where, due to their design, two guided piston rods plus pistons,

possibly hollow cylinder pistons - in addition to flow losses, relatively mechanical friction forces are to be overcome. On the other hand, are Gleichgangzylinder in the

Conveying facilities useful because they can be changed over their entire stroke from drag to the working mode.

Presentation of the invention

An object of the invention is to provide a synchronous cylinder, which in a compact, durable design of a foreign drive preferably in the electric or pneumatic motor or a hydraulic cylinder or the like with low loss, efficient and fast movement. A further object is to provide a forming device, preferably a pressing system, extrusion press or a ring rolling system, which realizes an efficient and fast method of the system between a working configuration and one or more other configurations in a compact, durable design.

The objects to be achieved with a synchronous cylinder with the features of claim 1, and a forming device with the features of claim 1 1. Advantageous further developments follow from the dependent claims, the following description of the invention and the description of preferred embodiments.

The synchronous cylinder according to the invention is a hydraulic cylinder, it has an outer cylinder and an inner cylinder inserted therein and arranged concentrically thereto. In the inner cylinder is a sliding, double-acting

Working piston introduced. For double-acting hydraulic cylinders or working pistons There are two opposing piston surfaces, which are supplied with hydraulic fluid. The hydraulic cylinder thus has two active directions of movement. For this purpose, the working piston divides the inner cylinder into two pressure chambers and can be acted upon by both pressure chambers with a hydraulic fluid. If there is a pressure difference between the two pressure chambers, a worker acts on the working piston. The working piston is further connected to a piston rod or integrally formed therewith or integrally, wherein the piston rod preferably protrudes from both ends of the outer cylinder and is guided there, such as by means of end-mounted cylinder locks. An annular gap between the inner cylinder and the outer cylinder and / or another direct connection, for example in the form of one or more bypass lines are available.

Furthermore, the synchronous cylinder has a bypass device with at least one, preferably two, bypass valves. The above-mentioned annular gap and / or the at least one bypass line are. Part of the bypass device. The bypass means is arranged such that at a particular position or position of the bypass valve, referred to herein as a bypass position, fluid communication is established between the two pressure chambers via the annular gap and / or the at least one bypass line and in a different position or position the bypass valve, which is referred to here as a working position, no such fluid connection (within the Gleichgangzylinders) is made. In other words, the bypass position allows fluid communication between the pressure chambers by flowing hydraulic fluid from one pressure chamber via the annular gap and / or the at least one bypass line into the other pressure chamber, while such

Fluid exchange is prevented in the working position.

The synchronous cylinder described has a compact design in which a bypass function, also referred to as a bypass function, is realized in a technically simple manner. The loop, which is made by the concentric cylinders - inner cylinder and outer cylinder - allows a low-loss bypass flow. The same applies, in addition to the ring line or alternatively for the at least one bypass line outside the cylinder housing. The working piston can thus be Energy-saving, low-loss and fast moving from a third-party drive. Due to the Gleichgangbauweise the hydraulic cylinder in each stroke position the full

Develop design power.

Due to the technical effects and advantages described above is the

Gleichgangzylinder particularly advantageous in the field of forming equipment, in particular pressing plants, extrusion or annular rolling mills applicable. The extrusion presses take a prominent position, since there is a rapid process of the pickup or possibly other parts of the system over a large stroke is desirable. The synchronous cylinder according to the invention combines in a synergetic manner a working operation and a towing operation over the entire stroke. In particular, the synchronous cylinder can be switched over the entire stroke between the working mode and the towing mode, ie the operation in which the bypass valve is brought into the bypass position and the

Synchronous cylinder from a third-party drive, such as one or more electric motors, is moved. Here are the flow losses and the internal friction of the

Synchronous cylinder reduced, so that the towing operation can be carried out energy-saving, energy-efficient and fast.

Preferably, the piston rod is designed so that it extends on both sides of the working piston and has the same diameter on both sides. In this way, the synchronous cylinder can be realized in a particularly technically simple manner, since in a cylindrical working piston, the contact surfaces for

Loading with the hydraulic fluid on both sides are the same size. On a fluidically disadvantageous hollow cylindrical piston can be omitted.

Preferably, in this case, the bypass valve is guided on the piston rod, this surrounds the piston rod preferably annular, and for switching between the bypass position and the working position, the bypass valve is axially displaced in this case. Thus, the piston rod is used synergistically as a guide and thus, as it were, as part of the bypass valve. This simplifies the technical structure of the Gleichgangzylinders, the error rate is reduced. Preferably, the bypass valve is by means of a spring in the bypass position or the working position, particularly preferably in the

Bypass position, biased. Basically, the operation of the

Bypass valve in various ways, such as electric, magnetic, hydraulic and / or mechanical. However, the bypass valve should be controllable from the outside. By biasing the bypass valve to one side, the structure is simplified, since an active actuation must be technically realized only along the other direction. Particularly Favor the bypass valve is firmly fixed in the working position, so that it is not inadvertently brought about by the pressure in the pressure chamber in the bypass position. According to a particularly preferred embodiment, the spring for returning or biasing the bypass valve is internal, d. H. at least partially provided within the outer cylinder, preferably completely within the housing or completely within the same through the head sections end-side synchronous cylinder.

Preferably, the bypass valve is hydraulically operable to provide a fault-tolerant, durable technical solution. Particularly preferred are the

Preload combined by a spring and the hydraulic solution. For the purpose of hydraulic actuation, the bypass valve is provided with an actuating fluid

Contact, which is supplied via an actuating line, optionally with an actuating chamber, and a suitable connection on the synchronizing cylinder.

The bypass device preferably has two bypass valves which are provided on the opposite sides of the working piston. As a result, the bypass path via the annular gap and / or the at least one bypass line can be realized in a technically simple manner. Particularly preferred here is an essentially mirror-symmetrical structure of the bypass device, optionally the entire Gleichgangzylinders used to homogenize the force characteristics. The bypass valve (s) are preferably provided at the end portions and the head sides of the synchronous cylinder, respectively, thereby maximizing the stroke. The Bypass valves, along with the piston surfaces and the inner cylinder, may provide a portion of those walls which form the pressure chambers.

The outer cylinder is preferably at its end portions each with a

Cylinder lock closed. The inner cylinder is preferably fixed at its end portions in each case preferably by means of a cylinder head carrier relative to the outer cylinder. For this purpose, the inner cylinder in the axial direction is preferably formed shorter than the

Outer cylinder. The terms "end face", "head face" and "face" are used synonymously and mean the outer sections of the synchronous cylinder, seen in the axial direction.

Preferably, a hydraulic fluid port is provided with a hydraulic fluid conduit that pierces the cylinder closure and / or the cylinder head carrier of the corresponding end side. The hydraulic fluid line with the hydraulic fluid port is in fluid communication with the corresponding pressure chamber and supplies it with

Hydraulic fluid.

The cylinder head supports may be components which contribute to the manufacture and definition of the bypass device, preferably the annular gap, as well as the hydraulic fluid lines. As a further function, they can support the technical structure of the bypass valves, because preferably the bypass valves are in contact with both the piston rod and with the corresponding cylinder head carrier. Thus, the structure of the Gleichgangzylinders simplified considerably, its error rate is reduced.

Preferably, the two cylinder head carriers each have one or more

Bypass lines, which establish a fluid connection between the pressure chambers and the annular gap and / or the at least one bypass line. In this case, the bypass valves in the working position preferably close the Fluid connection between the corresponding pressure chamber and the corresponding bypass line and open this fluid connection in the bypass position.

Although the invention is particularly preferred in the technical environment of

Extrusion plants is used, the invention can also be implemented in other areas, such as in the field of rolling mills or of general facilities for the plastic deformation of hard workpieces, such as metal blocks or sheets. Further advantages and features of the present invention will be apparent from the following description of preferred embodiments. The features described therein may be implemented alone or in combination with one or more of the features set forth above insofar as the features do not

disagree. The following description of the preferred embodiments is made with reference to the accompanying drawings.

Brief description of the figures

FIG. 1 shows the longitudinal section of a synchronous cylinder in a first embodiment

Embodiment of the invention.

2 shows a section of a longitudinal section through a synchronous cylinder with a modified structure.

FIG. 3 shows the installation position of a synchronous cylinder in the extrusion press.

FIG. 4 shows a further embodiment of the invention with an outer bypass line. FIG. 5 shows a further embodiment of the invention with a multiplicity of bypass lines integrated in the synchronizing cylinder.

Detailed description of preferred embodiments

In the following, preferred embodiments will be described with reference to FIG. Here are the same, similar or equivalent elements with identical

Reference numerals provided, and a repetitive description of these elements is partially omitted in order to avoid redundancies.

Figure 1 shows a synchronous cylinder 1. More precisely, the two

End portions of the cylinder 1 shown in longitudinal section, in the present

Embodiment are constructed essentially mirror-symmetrical.

The hydraulic cylinder 1 has a hollow outer cylinder 10, a hollow inner cylinder 20, left and right each having a head portion 30 and a piston rod 40 with an integrated or associated working piston 41. The head portion 30 has a cylinder head support 31 and a cylinder lock 33, whereby the hydraulic cylinder 1 is closed at both ends and the inner cylinder 20 is fixed relative to the outer cylinder 10. The inner cylinder 20 is introduced into the outer cylinder 10, both are concentric with each other, so that an annular gap 51, which is part of a later described in detail by-pass or bypass device 50, between the inner cylinder 20 and the outer cylinder 10 is formed. The working piston 41 is slidably mounted in the inner cylinder 20. The piston rod 40 extends on both sides of the working piston 41, pierces the respective head portions 30 and is through this guided. Not described in detail, but partially shown in the Figure 1 seals and parts for supporting the piston rod 40 and the working piston 41, which ensure trouble-free operation of the hydraulic cylinder 1 can be provided at appropriate locations.

Left and right of the working piston 41 are pressure chambers 42, which are surrounded by the working piston 41, the inner cylinder 20 and head-side components, such as a cylinder head carrier 31 and a bypass valve 52 described later, and thereby defined. The working piston 41 is acted upon by a pressure medium or hydraulic fluid - such as a hydraulic oil - from both sides, which is located in the pressure chambers 42. The hydraulic fluid is supplied via bores or lines, here referred to as hydraulic fluid lines 32, into the pressure chambers 42. The hydraulic fluid lines 32 extend through the two head sections 30. The hydraulic fluid lines 32 may include a hydraulic fluid port 32 ', a

Hydraulic fluid loop 32 "and other components that are suitable under

To supply pressurized hydraulic fluid to the pressure chambers 42, distribute and dissipate, have or be fluidly connected.

A pressure difference of the hydraulic fluid between the two pressure chambers 42 causes a force on the working piston 41, which can lead to a displacement of the working piston 41 in the axial direction and thus the piston rod 40. For this there is an influx of hydraulic fluid in one of the two pressure chambers 42, over the relevant

Hydraulic fluid line 32, and a displacement of the hydraulic fluid in the other pressure chamber 42 instead, wherein hydraulic fluid via the other hydraulic fluid line 32 is discharged. By the loading surface of the working piston 41 is the same size on both sides, the hydraulic cylinder 1 acts as a synchronous cylinder, which is also referred to as a synchronous cylinder. This mode of operation is referred to as a working mode, for the purpose of distinguishing from a towing mode described below, which allows a non-pressurized or low-pressure displacement of the working piston 41. For rapid, unpressurized movement of the working piston 41 - for example for adjusting or adjusting a pickup in an extrusion press - the hydraulic cylinder 1 has a bypass device 50. This comprises in the present embodiment, the annular gap 51, the two bypass valves 52, bypass lines 53, which are in fluid communication with the annular gap 51, and actuators 54. The two bypass valves 52 are on the piston rod 40, in the region of the two

Head portions 30 out and open and close the bypass lines 53 by being actuated by the actuator 54 in the axial direction, i. be moved. When the bypass valve 52 is open, the hydraulic fluid from the

When both bypass valves 52 are opened, the working piston 41 can be displaced in this way without power or force, since a fluid connection between the two pressure chambers 42, over the bypass lines 53 and the annular gap 51 consists. In this case, the annular gap 51 allows by its external arrangement and annular shape a fluidically particularly optimal behavior.

The operation of the bypass valves 52 via the actuators 54. These have in the present embodiment, a spring-biased actuating rod 54 'which extends through the respective head portions 30 and is connected to the bypass valve 52, and an actuating hydraulic portion 54 "with an actuating port 54th '', a hole and a chamber (without

Reference numeral). By biasing the bypass valve 52, here

For example, by means of the spring, the bypass valve 52 is automatically brought into a preferred position. By introducing or discharging a fluid into the actuating hydraulic section 54 "via the actuating port 54" ', the

Actuating valve 52 is actuated.

The bypass device 50 for pressure-free or low-pressure method of

Working piston 41 is realized by means of the annular gap 51 described above, which passes around the outer side of the working piston 41 through the concentric hollow cylinders 10 and 20. This technical solution is space-saving and with regard to the flow conditions excellent, because the annular gap 51 has the lowest flow losses in

Comparison to other solutions. The here exemplified, on the

Piston rod 40 guided, concentric, annular bypass valves 52 allow quick and safe switching of the modes of the hydraulic cylinder. 1 A targeted control of the flow of hydraulic fluid between the two pressure chambers 42, and from the annular gap 51 in the pressure chambers 42 is realized in a technically simple, fehlerunanfällige and durable manner. Furthermore, the technical solution shown here has a small number of hydraulic connections, which further simplifies the operation of the hydraulic cylinder 1.

FIG. 2 shows a structure modified with respect to the actuating device 54. For the purpose of illustration, only a section of the longitudinal section is shown by the synchronous cylinder 1, but this can - as in the figure 1 - be constructed essentially mirror-symmetrical.

In contrast to the synchronous cylinder of Figure 1, the actuator 54 for actuating the bypass valves 52 no actuating rod 54 'with external return spring, but the provision or bias of the bypass valve 52 via an inner spring 55. The Betätigungshydraulikabschnitt 54 "with the operating terminal 54"' are essentially unchanged. At the end of

Actuating hydraulic section 54 ", which is opposite to the actuation port 54" ', is an annular chamber (without reference numeral but clearly visible in FIG. 2)

provided adjacent to one side of the bypass valve 52. The actuation of the bypass valve 52 takes place as in the embodiment of Figure 1; d ,. H. by biasing the bypass valve 52, here according to Figure 2 by means of the internal spring 55, the bypass valve 52 is automatically brought into a default position. By introducing or discharging a fluid into the actuation hydraulic portion 54 "via the actuation port 54" ', the actuation valve 52 is actuated.

Due to the slim design, the synchronous cylinder 1 can be guided by a cylinder spar of an extrusion press. For this reason, the hydraulic cylinder is 1 particularly preferably used in the field of extrusion presses, in particular for the realization of the transducer kinematics, including the power function. It has the great advantage that it can be changed over from the trailing to the working mode by the unpressurized adjustment over the entire stroke. Thus, the synchronous cylinder 1 is able to support in all positions any electric motors for quick travel over the entire stroke with the full cylinder force.

The installation position of the synchronous cylinder 1 in an extrusion press system 100 is shown in FIG. The synchronous cylinder 1, the structure of which is shown in less detail in FIG. 3 than in the preceding figures, is guided by a cylinder spar 101. One side of the piston rod 40 is connected to a pickup 102 which is movable over the synchronous cylinder 1, such as between a position for block change and a front end position, the working position at which the pressing, airing and stripping takes place. Alternatively, the transducer 102 can be moved over one or more electric motors, not shown, which the transducer 102 between the

Move block change position and working position. The Gleichgangzylinder 1 is moved externally,. For such a foreign movement, d. H. for fast, depressurized operation of the synchronous cylinder 1, this is switched in the manner described above in the towing mode.

FIG. 4 shows an alternative embodiment of a device according to the invention

Gleichgangzylinders 1, in which, unlike in the first embodiment according to Figures 1 to 3, a bypass means 50 is arranged in the form of a bypass line 103 outside the housing and the pressure chambers 42 via respective bypass valves 52 with each other. The bypass line 103 replaces the

Annular gap between outer cylinder 10 and inner cylinder 20 according to the

Embodiments of Figures 1 to 3. However, the bypass line 103 causes the same technical effects as the annular gap 51 according to the embodiments of Figures 1 to 3. FIG. 5 shows a further embodiment of the invention

Synchronous cylinder 1 in a side view and a cut along the line AA of Figure 5 frontal view. From the front view according to Figure 5b it can be seen that within the housing of the synchronous cylinder 1 outside the outer cylinder 10 four bypass lines 103a-d are arranged. This bypass

Lines 103a-d as well as the bypass line 103 in FIG. 4 completely replace the annular gap 51 according to the embodiments of FIGS. 1 to 3. The bypass lines 103a-d, like the bypass line 103 according to FIG. 4, connect the pressure chambers 42 of the synchronous cylinder 1.

Where applicable, all individual features illustrated in the embodiments may be combined and / or interchanged without departing from the scope of the invention. Not all of the exemplary

Embodiments illustrated technical features must be essential to the invention. Thus, for example, the inflow and outflow between the annular gap 51 and the pressure chambers 42 can be different than by means of the one shown here

Realize bypass lines 53. The bypass valves 52 may be constructed and / or positioned differently, although the technical solution outlined is preferred.

LIST OF REFERENCE NUMBERS

1 synchronous cylinder

10 outer cylinders

20 inner cylinders

30 head section

31 cylinder head carrier

32 hydraulic fluid line

32 'hydraulic fluid port 32 "hydraulic fluid loop

33 cylinder lock

40 piston rod

41 working piston

42 pressure chambers

50 bypass device

51 annular gap

52 bypass valve

53 bypass

54 Actuator 54 'operating rod

54 "actuating hydraulic section

54 "'operating connection Spring for biasing the bypass valve extrusion plant

cylinder beam

pickup

Bypass line

Claims

claims

1 . Synchronous cylinder (1), preferably for an extrusion press, with a

Outer cylinder (10), one inserted therein and concentric to it

arranged inner cylinder (20), a slidably provided in the inner cylinder, double-acting working piston (41) and a

Bypass device (50) with at least one bypass valve (52), wherein the working piston (41) divides the inner cylinder (20) into two pressure chambers (412) and from both pressure chambers (42) with a hydraulic fluid

can be acted upon, wherein the bypass device (50) is arranged so that in a bypass position of the bypass valve (52), a fluid connection between the two pressure chambers (42) via a direct connection,

preferably at least one bypass line, is manufactured and in a working position of the bypass valve (52) there is no such fluid connection.

2. synchronous cylinder (1) according to claim 1, characterized in that the

Direct connection, preferably the bypass line, between the outer cylinder and the inner cylinder of the Gleichgangzylinders (1) is arranged.

3. synchronous cylinder (1) according to one of claims 1 or 2, characterized

in that the bypass line is arranged outside the Gleichgangzylinders- housing.

4. synchronous cylinder (1) according to one of the preceding claims, characterized

characterized in that the bypass valve (52) by means of a spring (55) in the bypass position or the working position, preferably the

Bypass position, is biased.

5. synchronous cylinder (1) according to claim 4, characterized in that the spring (55) for resetting or biasing of the bypass valve (52) partially or completely in the outer cylinder, preferably completely within the is provided by head sections (30) on the head side completed Gleichgangzylinders (1).

Synchronous cylinder (1) according to one of the preceding claims, characterized in that the bypass valve (52) is hydraulically actuated.

Synchronous cylinder (1) according to one of the preceding claims, characterized in that the bypass device (50) has two bypass valves

(52) provided on the opposite sides of the working piston (41).

Synchronous cylinder (1) according to one of the preceding claims, characterized in that the outer cylinder (10) is closed at its end portions each with a cylinder closure (33), the inner cylinder (20) at its end portions in each case by means of a cylinder head carrier (31) relative to the outer cylinder (10) is fixed and at both ends in each case a hydraulic fluid connection (32 ') and a hydraulic fluid line (32) which in the

Cylinder closure (33) and / or cylinder head carrier (31) of the corresponding side is introduced, is provided.

Synchronous cylinder (1) according to claim 8, characterized in that the two cylinder head carrier (31) each have one or more bypass lines

(53) which establish fluid communication between the pressure chambers (42) and the annular gap (51).

0. Gleichgangzylinder (1) according to claim 7 and 9, characterized in that the bypass valves (52) with both the piston rod (40) and with the corresponding cylinder head carrier (31) are in contact, in the working position, the fluid connection between the corresponding pressure chamber (42) and the Close the corresponding bypass line (53) and in the

Open the bypass position.

Forming device, preferably pressing system, extruder or ring rolling mill, with one or more Gleichgangzylindern (1) according to the preceding claims.

Forming device according to claim 1 1, characterized in that one or more electric motors for adjusting the Gleichgangzylinders (1) are provided.