DE102017003963A1 - Hydraulic, in particular pressure accumulatorless, drive arrangement for and with a consumer, in particular for presses, and method for operating a hydraulic drive assembly - Google Patents

Abstract

In a pressure accumulator-free hydraulic drive assembly (10) with a press, with a double-acting, a cylinder chamber comprising piston / cylinder assembly (20), in which a reversibly movable piston (21) pressurizing fluid pressure, the first piston chamber (23A) and a second piston space (23C), with pressure lines (D1, ...), with a pump arrangement (30; 30A, 30B), which a variable speed driven pump (31; 32) and a pump (31, 32) driving variable speed Drive (33), with a pressure medium supply, in which the pump (31) via a first pressure line (D1) to the first piston chamber (23A) is connected, so that the hydraulic drive assembly (10) by means of a single single-motor drive train in both a direction of movement is operable and achieved in the operation high working pressures, an improved utilization of the drive motor and its inverter is achieved by a hydromechanical St ell cylinder (51; 51A) of the pump (32), a hydraulic connecting line (D1 ') acting between the actuating cylinder (51, 51A) and the pressure line (D1) provided between the one pump (32) and the associated piston chamber (23A), and by a proportional valve (50, 50A), wherein the valve in the connecting line (D1 ') between the actuating cylinder (51, 51A) and the pressure line (D1) is hydraulically effective, that by varying the position of this valve by means of an external Position of the hydraulic valve influencing control signal of the actuating cylinder (51, 51A) can be acted upon by a variable pressure.

Description

FIELD OF THE INVENTION

The invention relates to a hydraulic, in particular accumulatorless, drive arrangement for and with a consumer, in particular for presses with the features of the preamble of claim 1 or 10 and a method for operating a hydraulic drive assembly with the features of the preamble of claim 4 or 5.

Accordingly, the invention is based on a hydraulic drive arrangement with at least one working piston and, if necessary, a supplementary rapid traction piston and, if appropriate, a ring-like return piston, in particular if it comprises a double-acting piston comprising at least one reversibly movable working piston and at least one cylinder chamber. Cylinder arrangement comprises, wherein the at least one cylinder chamber or the cylinder chambers at least one of the working piston with fluid pressure acting on the (first) piston chamber and, preferably, at least one second piston chamber comprises / include. The piston chambers can be supplied via pressure lines with a pressure medium. At least one pump arrangement is provided with at least one, preferably at least variable speed driven, pump and with at least one at least one pump driving, preferably variable speed, drive. At least one pressure medium tank hydraulically connected or connectable to the piston / cylinder arrangement and the pump arrangement can be provided. The at least one pump can be connected or connectable via a first pressure line to the first piston chamber, so that the hydraulic drive arrangement can be operated by means of at least one single-motor drive train in both directions of movement and, preferably, also reaches high working pressures during the operation. An adjusting device of the at least one pump with an adjusting means can be provided for the latter, wherein the delivery flow of the at least one pump can be changed by means of the adjustment device which can be actuated by the adjusting means. The hydraulic accumulator-free hydraulic drive arrangement can comprise a third piston chamber which supplements the first piston chamber and which is replaced by a Pressure line is supplied. The one or the piston chamber / spaces with pressure medium supplying / n pump speed and, if desired, also rotational direction variable can be driven or driven.

TECHNOLOGICAL BACKGROUND

Variable speed hydraulic drives, especially for large cylinders, are approximately corresponding to the WO 2010/020427 or WO 2012/110259 executed. In the former, two separate pump drive arrangements for the working stroke on the one hand and the return stroke on the other hand are provided to save large-volume pressure accumulator. The hydraulic cylinder may be equipped with an additional rapid traverse piston chamber. The disadvantage is the high construction costs for the two motor pump stations. Especially with large consumers, the inverter controls and power supplies used for the motor drive are quite expensive. The large directional control valves for switching the pump delivery flow from rapid traverse piston to the large piston surface are also expensive.

Second is based, starting from the WO2010 / 020427 to provide on the concept, in a pressure accumulatorless hydraulic drive assembly with working piston, additional rapid traverse piston and ringlike Rückholkolben a Drehrichtungsvariable pump assembly of a variable speed motor with at least two pumps and the three cylinder (or piston) spaces via three pressure lines individually and directly to the pump to connect such that in both directions a rapid traverse takes place.

The servomotors currently used as servomotors and the associated converters are very cost-intensive; A reduction of the drive torque would significantly reduce the costs for the use of so-called variable displacement pumps in variable-speed hydraulic drives. The variable displacement pumps used so far are based on a pump-internal, usually purely hydromechanical torque or pressure control of the delivery flow. The adjustment (the adjustment) of the variable / / for the piston and possibly the annular space of the working cylinder is characterized by an adjusting means in the form of a hydraulic cylinder with spring return. As the operating pressure of the variable displacement pump increases, the variable displacement pump pivots against the spring and pivots back the variable displacement pump so that the flow rate per pump revolution (displacement) decreases. The drive torque of the drive motor is proportional to the product of hydraulic pressure and displacement of the driven working piston. By a suitable choice of the spring characteristic, it is possible to keep the engine drive torque almost constant pressure-independent and not to exceed the rated torque of the engine. When the operating pressure of the (variable) pump increases, its delivery flow is reduced so far that the drive torque of its drive motor remains largely constant. Alternatively, an electrical adjustment of the variable displacement is known.

It has also been found that most applications of hydraulic drive assemblies require long rapid traverse paths with little load, while the high load phases require little Make up time shares. Examples of such processes include forming or straightening tasks where high process forces are needed for less than 10 percent of the total cycle time. An improved use of the available drive torque of the engine would therefore also be desirable.

PRESENTATION OF THE INVENTION

The object of the invention is therefore to further develop a generic drive arrangement so that the utilization of the drive motor and possibly also the inverter can be improved.

To solve the problem, a possibly pressure accumulatorless hydraulic drive arrangement for and with a consumer, in particular for presses with the features of claim 1 or 10 and a method having the features of claim 4 or 5 is proposed. Accordingly, the invention is based on the WO 2010/020427 or the WO2012 / 110259 on the method concept (claim 5) that in a generic hydraulic drive assembly caused by a hydromechanical or mechanical pump regulation or adjustment change, in particular reduction, the flow of the at least one pump by means of a hydromechanical or mechanical pump control superimposed or the pump adjustment causing, externally controllable hydraulic or mechanical drive device is delayed so far until the drive torque of the engine is utilized as much as desired.

By the invention can u. A. the flow rate of the pump to the current state of the motor or the inverter to be timed. In particular, the drive torque of the motor and the thermal or electrical limits of motor or inverter can be exploited as much as desired. So u. A. a reduction in the flow rate of the pump be delayed until the thermal or electrical limits of the motor or inverter are used as far as desired.

It can also be provided a combination of drive arrangement and downstream valve controls. The speed variability can be achieved with at least one asynchronous motor and at least one frequency converter. If desired, a reversal of the direction of rotation of the pump can be achieved without the motor itself having to reverse its direction of rotation. If desired, further, the swash plate of the (axial piston) pump beyond the angle "0 °" out, in particular in the negative angle range, are rotated, so that the (gear and pressure) ports of the pump each reverse their function.

According to a (first) realization of the invention, it is in a known autarkic purely hydromechanical, a Pumpenverstell-, in particular -Verschwenkeinrichtung, and an actuating piston comprehensive control of the flow of the at least one pump - cumulative or alternatively - provided, the input pressure of the actuating piston by means of a external, in particular electrically controlled, hydraulic valve, in particular proportional valve, to be superimposed to change such that is acted upon by the variation of the position of this hydraulic valve, the actuating piston of the pump adjustment by means of the external, in particular electrical, control signal with a variable pressure, in particular according to claims 1, 4 or 11th

The adjustment of the pump can therefore comprise a known hydraulic cylinder, possibly with (spring) reset. As the operating pressure increases, the pump pivots against the return (spring). When swiveling forwards and / or backwards, the flow rate per pump revolution (displacement) is changed.

• – bei der, gemäß Anspruch 10, mindestens eine, vorzugsweise externe, insbesondere elektrisch gesteuerte, Antriebseinrichtung zur Variation der Stellung des Stellmittels der Verstelleinrichtung der mindestens einen Pumpe vorgesehen ist, und
• – bei der als Stellmittel der mindestens einen Pumpe mindestens ein hydro-mechanisches Antriebsglied, wie einen Stellzylinder dient,

vorgesehen, dass die mindestens eine Antriebseinrichtung zur Variation der Stellung des Stellmittels der Verstelleinrichtung der mindestens einen Pumpe eine (zweite) Pumpe sowie ein der (zweiten) Pumpe zugeordnetes Antriebsmittel umfasst, wobei die (zweite) Pumpe mit dem Stellmittel der mindestens einen Pumpe, im Verstellsinn fluidisch verbunden ist, und dass durch Steuern des der (zweiten) Pumpe zugeordneten Antriebmittels mit Hilfe eines externen, insbesondere elektrischen, die Fördermenge der (zweiten) Pumpe beeinflussenden Stellsignals das Stellmittel in variable Stellungen verlagerbar ist.According to an alternative (second) realization of the invention (claim 12), it is in a hydraulic, in particular pressure accumulatorless, drive arrangement for and with a consumer, in particular for pressing,

• - In which, according to claim 10, at least one, preferably external, in particular electrically controlled, drive means for varying the position of the actuating means of the adjusting device of the at least one pump is provided, and
• In which at least one hydro-mechanical drive element, such as a setting cylinder, serves as setting means of the at least one pump,

provided that the at least one drive means for varying the position of the adjusting means of the adjusting of the at least one pump comprises a (second) pump and one of the (second) pump associated drive means, wherein the (second) pump with the actuating means of at least one pump, in Verstellsinn is fluidically connected, and that by controlling the (second) pump associated drive means with the aid of an external, in particular electrical, the flow rate of the (second) pump influencing control signal, the adjusting means is displaceable in variable positions.

The drive device for varying the position of the adjusting means of the adjusting of the at least one pump of the drive assembly is also in this alternative (second) implementation of the invention of a hydraulic nature, although - unlike the first implementation - not the Working or operating pressure of the drive assembly itself but the working pressure of a comparatively small, externally driven (further) pump is used.

• – bei der, gemäß Anspruch 10, mindestens eine, vorzugsweise externe, insbesondere elektrisch gesteuerte, Antriebseinrichtung zur Variation der Stellung des Stellmittels der Verstelleinrichtung der mindestens einen Pumpe vorgesehen ist, und
• – bei der als Stellmittel der mindestens einen Pumpe mindestens ein mechanisches Antriebsglied, wie eine Stellspindel (51C), dient,

vorgesehen, dass die mindestens eine Antriebseinrichtung zur Variation der Stellung des Stellmittels der Verstelleinrichtung der mindestens einen Pumpe ein dem mindestens einen mechanischen Antriebsglied zugeordnetes Antriebsmittel umfasst, und dass durch Steuern des dem mechanischen Antriebsglied (Stellmittel) zugeordneten Antriebmittels mit Hilfe eines externen, insbesondere elektrischen, die Stellung des Antriebsmittels beeinflussenden Stellsignals das Stellmittel in variable Stellungen verlagerbar ist.According to a further alternative (third) realization of the invention (claim 13), it is in a hydraulic, in particular pressure accumulatorless, drive arrangement for and with a consumer, in particular for presses,

• - In which, according to claim 10, at least one, preferably external, in particular electrically controlled, drive means for varying the position of the actuating means of the adjusting device of the at least one pump is provided, and
• In which as actuating means of the at least one pump at least one mechanical drive member, such as an adjusting spindle ( 51C ),

that the at least one drive device comprises a drive means assigned to the at least one mechanical drive element for varying the position of the actuating means of the adjusting device of the at least one pump, and that by controlling the drive means associated with the mechanical drive element (actuating means) by means of an external, in particular electrical, the position of the drive means influencing the control signal, the adjusting means is displaceable in variable positions.

The drive means for varying the position of the adjusting means of the adjusting of the at least one pump of the drive assembly is mechanical in this alternative (third) implementation of the invention, however - unlike the first and second realization - not a pump pressure but the adjustment of the external drive means itself is used.

The use of the delivery flow adjustment according to the invention can be realized with a variety of circuit concepts, in particular variable speed, motor-pump combinations such. B. with a single motor pump station with one or more pumps of which at least on a pump, an adjustment according to the invention or with multiple motor pump stations, each having one or more pumps wherein at least at a motor pump station, a flow adjustment after Invention is provided.

Known variable-speed hydraulic drives have drive motors that can be loaded for a short time well beyond the rated torque. For example, a factor that is four times faster can be called up for about two seconds, and a 10 percent overrun is allowed for several minutes. The higher limits are determined by the thermal capacity of the motor windings and the power semiconductors of the inverter. The current I is quadratic, the duration t of the current is linear. For assessing the limits of the system, the respective load collective is evaluated ("I ^2nd t-bill"). This potential can be used by the invention in a simple and cost-effective manner, whereas known hydraulic drives automatically limit the engine torque by pivoting the pump, so that a higher torque without use of the load values of inverter and motor can therefore be used only for a short time only limited.

Adjustable pump controller according to the invention, without further control modules and sensors z. B. controlled directly from the inverter. The scheme should such be done preferably that determined according to the internal inverter I ² t calculation by the converter current load factor of the engine and drive the pump is operated as long as possible with a high tilt angle in order to utilize the motor and inverter optimal. The flow rate increased in this way makes it possible to significantly shorten the system cycle time or, alternatively, to select a smaller drive motor. It was also recognized that the above-mentioned, typical load profiles of a press with only a short time higher forces allow it to retrieve significantly higher moments during the work process, if the subsequent rapid traverse and breaks for loading and unloading the system are used again for cooling ,

According to the invention it may therefore be advantageous to use the current utilization rate as a control variable. Preferably, on the one hand, the load value of the motor and the converter is considered, but on the other hand, the rate of change of this value. With a rapidly increasing load value, the adjustment of the pump, such as the swivel angle, to reduce the engine torque is relatively quickly withdrawn, while at a slowly increasing load value adjustment can be slower or even completely omitted.

In addition to the load factor for motor and drive can be considered according to the invention as a further control variable for adjusting the pump and the knowledge of the respective work process of the entire system. If it is known, for example, that a particularly high power requirement is only needed for a short period of time, then a high degree of adjustment, such as a high swivel angle, can be maintained, although the course of the load factor indicates an imminent emergency shutdown.

The hitherto carried out according to the prior art, from which the invention proceeds In contrast, as previously mentioned, variable-speed drives are based only on a pump-internal, usually purely hydromechanical regulation of the delivery flow. With increasing pressure, the flow rate of the pump is automatically withdrawn so far that the drive torque of the motor, which is proportional to the product of hydraulic pressure and displacement remains largely constant. This made it possible by suitable choice of the spring characteristic to keep the engine drive torque pressure-independent almost constant and not to exceed the rated torque of the engine. Examples of such a hydro-mechanically torque-controlled pump is about the type A4VSO-LR2 BoschRexroth. Characteristic of this known control is the fact that the adjustment is done inside the pump and responsible for the motion control inverter has no influence on it. Alternatively, these self-sufficient, purely hydromechanical controllers could, for example, also be designed so that the operating pressure is kept constant as a control variable for the variation of the displacement (pressure regulator). This was useful in such control for that pump which was connected to the annular space of the cylinder. It had only the task to support the cylinder and possibly attached masses against gravity and to prevent cavitation of the associated with the annulus pump when driving uphill.

In addition to these hydromechanical controllers are currently also electrically influenced controller known. So z. B. today used inverter track the utilization of the motor and the inverter itself constantly and they limit the power automatically when the thermal limits are reached. Also, the respective degree of utilization of inverter and motor can be made available at an electrical interface as a numerical value for the machine control. Available for the above pump are also such regulators - z. B. in the form of the controller type DFE1 - which allow the influence of the pump by external control signals for flow or pressure. The electrically influenced controllers require their own control electronics and have sensors for the actual values z. B. swivel angle and pressure. However, the additional equipment and costs of the control system make the pump significantly more expensive.

• – Bessere Ausnutzung von Motor und Umrichter;
• – Geringer Anschaffungspreis durch Entfall einer eigenen Pumpensteuerung und Sensoren für Schwenkwinkel und Druck;
• – Günstigere Taktzeiten;
• – Anwahl energieoptimaler Betriebspunkte für Motor und Pumpe möglich (schlechte Wirkungsgrade bei sehr geringer Drehzahl);
• – Erhöhung der Maschinensicherheit: Gezieltes Schwenken der Pumpen auf „0” mindert die Gefahr einer ungewollten Bewegung;
• – Ggf. Verzicht auf Umkehrung der Drehrichtung des Motors, insbesondere durch Schwenken der Pumpe über „0°” hinaus.

By the invention are compared to and opposite to in the WO 2012/110259 described solution from which the invention proceeds, u. A. achieves the following advantages:

• - Better utilization of motor and inverter;
• - Low purchase price by omitting own pump control and sensors for tilt angle and pressure;
• - More favorable cycle times;
• - Selection of energy-optimal operating points for motor and pump possible (poor efficiencies at very low speed);
• - Increased machine safety: Targeted swiveling of the pumps to "0" reduces the risk of unwanted movement;
• - Possibly. Not to reverse the direction of rotation of the motor, in particular by pivoting the pump beyond "0 °".

The above-mentioned and the claimed and described in the embodiments described components to be used in their size, shape design, material selection and technical design are not subject to any special conditions, so that the well-known in the field of application selection criteria can apply without restriction.

Further details, features and advantages of the subject matter of the invention will become apparent from the subclaims, as well as from the following description of the accompanying drawings and table, in which - by way of example - an embodiment of a pressure accumulator hydraulic drive arrangement are shown. Also, individual features of the claims or of the embodiments may be combined with other features of other claims and embodiments.

BRIEF DESCRIPTION

In the drawing show:

1 a (first) embodiment of an accumulatorless hydraulic drive assembly with an external, in particular electrically controlled, drive means for influencing the position (position) of a hydromechanical drive member (adjusting means) of the adjusting the at least one pump of the drive assembly, wherein the drive means, the position of the actuating means for influencing the Flow of the at least one pump by means of the working pressure of the drive assembly hydraulically overlapping changed - as a block diagram;

2 a (second) embodiment of an accumulatorless hydraulic drive assembly with an external, in particular electrically controlled, drive means for influencing the position (position) of a hydromechanical drive member (adjusting means) of the adjusting the at least one pump of the drive assembly, wherein the drive means the position of the actuating means for influencing the Flow of the at least one pump by means of the working pressure of the drive assembly hydraulically overlapping changed - as a block diagram;

3 an alternative implementation of a hydraulic drive assembly with an external, in particular electrically controlled, drive means for influencing the position (position) of a hydromechanical drive member (adjusting means) of the adjusting the at least one pump of the drive assembly, wherein the drive means the position of the actuating means for influencing the flow of at least a pump hydraulically changed by means of the working pressure of a separate pump - as a block diagram;

4 a further alternative realization of a hydraulic drive assembly with an external, in particular electrically controlled, drive means for influencing the position (position) of a mechanical drive member (adjusting means) of the adjusting the at least one pump of the drive assembly, wherein the drive means the position of the mechanical drive member for influencing the flow the at least one pump mechanically changed by means of a mechanical drive member associated drive means - as a block diagram;

5 one compared to the further alternative realization 4 modified (second) embodiment - as a block diagram,

6 one compared to the further alternative realization 4 or 5 modified (third) embodiment - as a block diagram

7 one compared to the further alternative realization 4 . 5 or 6 Changed (fourth) embodiment - as a block diagram.

DETAILED DESCRIPTION OF EMBODIMENTS

From the 1 is a double-acting, a working piston 21 , a piston rod 22 and a cylinder chamber comprising piston / cylinder arrangement 20 can be seen in the reversible movable piston 21 the cylinder chamber on the one hand in a first piston chamber 23A (or working cylinder) and on the other hand into a piston rod 22 surrounding second piston chamber 23C (or annulus or Rückholzylinder) divided. A rapid motion piston, not shown in this and the other figures, but which can be used, can be inserted into a piston rod 22 in the opposite direction, or be oriented in a same direction with the piston rod. The piston / cylinder arrangement 20 is at a the first piston chamber 23A with a pressure medium supplying the first pressure line D1 and to an optional, the optional annulus 23C connected with pressure medium supplying the second pressure line D3.

A single, designed as a servomotor drive 33 drives a double pump in the form of two, in particular variable speed pumps 31 . 32 on a single drive shaft 33A at. Both pumps are each equipped with one device ( 50 . 51 'D1'; D3 ') equipped for adjusting their delivery volume. The adjustment takes place on the one hand, in particular pump-internally, in each case by a control device (adjusting device 38 ; 38A . 38B ), in particular in the form of adjusting cylinders 51 ; 51A . 51B , the flow in a known manner the current, over the connecting lines D1 'and D3' pending at her operating pressure of the associated pump 31 respectively. 32 following, for. B. by means of a pump pivoting mechanism 52 , changed. In addition, according to the invention, a hydraulically upstream adjusting device 50 (Hydraulic valve) in the form of a proportional valve; 50A . 50B used per pump, which responded to hydraulic or, in particular, electrical control variables of an external control, such as in an inverter. Thus, the pump flow in dependence on an external input signal up to the maximum flow - the operating pressure of the associated pump 31 and or 32 overlaying - hydraulically adjusted. The drive device 60 for this superimposed flow adjustment is therefore hydromechanical nature and includes - in addition to the connecting lines D1 'and D3' for the supply of the hydraulic valves 50 with pressurized fluid - via signal lines 150A respectively. 150B externally controlled and electrically adjustable hydraulic valves 50 , The latter throttle - as described in more detail below - depending on the state of the drive 33 and / or the inverter U, the amount of fluid for adjusting the flow rate of the associated pump 31 respectively. 32 through the hydromechanical drive member 51A respectively. 51B ,

The servomotor 33 nearest pump 32 is in the present embodiment with serving as a working cylinder piston chamber 23A and the other pump 31 with the opposite piston chamber 23C hydraulically connected. The pumps 31 . 32 are on one side with a tank 40 and on the other side with the piston chamber 23A or with the annulus 23C fluidly connected. The on the piston rod 22 installed encoder 36 the current piston position signals the drive to one 33 Powered inverter U.

A possibly existing mechanical transmission 37 for torque transmission from the drive 33 , as shown in the other figures as an option, is associated with both pumps of the same drive train, in particular in order to use motors with relatively high speeds compared to the pumps. It is also helpful if the pump assembly is a brake includes, in particular to promote a switching valveless operation.

The following mode of operation / construction are preferred:

A) Pump, in particular Schwenkwinkel-, Verstellsystem

Starting from the hydraulic drive system according to WO 2012/110259 is in or z. B. at the ends of at least one connecting line D1 ', D3' at least one hydraulic valve, in particular a proportional valve 50A respectively. 50B hydraulically connecting installed. The at least one connecting line D1 ', D3' is provided between / for at least one of the pumps 32 respectively. 31 assigned, actuating cylinder / n 51A respectively. 51B and the pressure lines D1 and D3 of the pumps 32 respectively. 31 , The adjusting cylinders 51A respectively. 51B can into their respective assigned pump 32 respectively. 31 be integrated. By varying the piston position of these hydraulic valves, the actuating cylinder 51A respectively. 51B be subjected to a variable pressure, which can be adjusted within the limits of 0 to the applied pump pressure. Thus, the respective pump with, in particular one each, z. B. electrical, control signal externally via the proportional valves 50A respectively. 50B be adjusted. To control the two hydraulic / proportional valves, currently available, freely programmable control systems can be used in currently available converters. The control algorithm can access all system sizes of the drive (eg engine utilization, engine temperature, tappet travel position, torque and engine speed) for optimal control of the pump displacement, particularly the pump swing angle. The existing sensors for the position, in particular the swivel angle, and pressure can be omitted, because with the current signals of the cylinder position sensor and the inverter internally available values for motor current and speed and, if necessary, a mathematical model of the pump behavior swivel angle and system pressure can be calculated indirectly. In addition, it is possible and so far preferred to install the pump without maintenance problems to save space and sound-insulating below the oil level.

The with the piston chamber 23A connected pump 32 For example, it is only then adjusted, in particular swung back, when the degree of utilization of the engine 33 this requires. The one with the annulus 23C connected pump 31 is pivoted, for example, so that the pressure on the annular space side to compensate for gravity is around 20 bar.

For the control of the two proportional valves, currently available, freely programmable systems can be used in currently available converters. The control algorithm can, in particular, on all system sizes of the drive 33 (For example, degree of utilization of the engine, engine temperature, travel position of the plunger, torque and speed of the engine) to use them for optimal control of the pump (ver) position, in particular the pump swivel angle.

To extend the on the working piston 21 provided piston rod 22 at rapid speed promotes rotation of the servomotor 33 the pump 32 Oil in the piston chamber 23A , At the same time the pump sucks 31 Oil from the annulus 23C , The filling of serving as a working cylinder piston chamber 23A required oil flow may be from the tank 40 be sucked. The pump 31 is z. B. by the common shaft 33A to the pump 32 through the servomotor 33 at the same speed as the pump 32 but driven in opposite directions. The flow rate is preferably adjusted to the maximum via the adjustment of each pump. This happens at comparatively low pump pressure.

The pump fills to switch to working speed 32 the big piston chamber 23A alone. The delivery volume of the pump 32 is withdrawn, optionally with pressure-dependent or with overlaying help of the proportional valve controlled by the inverter 50A to a predefinable value.

The positioning is done in the usual way by stopping the servomotor 33 ,

For decompressing the direction of rotation of the servomotor 33 vice versa. The pressurized oil drives the servomotor, which now acts as a generator. The resulting electrical energy can be fed back into the electrical grid.

For the upward drive, an approximately existing filling valve is opened, the reversed pump 31 now promotes into the annulus 23C the piston / cylinder arrangement 20 so that the piston rod 22 retracts at rapid traverse speed. In addition, the pump sucks 32 the oil from the piston chamber 23A , The pump 31 is preferably operated at full flow to support a possibly provided switchable filling valve during emptying of the working cylinder.

B) Pump, in particular swivel angle control, according to drive utilization

On the one hand, the utilization value of motor and inverter is considered, on the other hand but also the rate of change of this value. With a rapidly increasing utilization value, the swivel angle for reducing the engine torque must be reduced relatively quickly, while with a slowly increasing load value, an adaptation can take place more slowly or even completely cease.

C) Optimized pump, in particular swivel angle control from process data

An additional possibility of regulating the pump (ver) position, in particular the pivot angle, is possible if the actual process flow for the individual cycles of the entire system repeatedly repeated in relation to the force-speed profile in a very similar form. This is the case, for example, with forming or straightening processes. In addition to the current measurement data, knowledge about the next periods of time can provide valuable information about the optimal swivel angle adjustment of the pump. The knowledge of the process flow can, for example, be taken from parameter lists created for the respective process.

It is also possible to use self-learning algorithms for the optimization, which always further improve the swivel angle adjustment, starting from a rather "cautious" setting up to the utilization optimum. The pump connected to the annular space is pivoted, for example, so that the pressure on the side of the annular space to compensate for the force of gravity is around 20 bar.

The embodiment according to 2 Each contains a motor pump station for the piston and annulus. Here are a first and a second drive motor 33C respectively. 33B provided with inverter. The for the annulus side 23C However, significantly lower requirements for flow rate and pressure require only a small engine power and small pumps. In addition, a simple constant pump 34 for the annulus side 23C be used. The variation of the flow to the annulus side 23C is achieved only via the engine speed. When the cylinder space is arranged vertically, it is particularly advantageous to keep the annulus pressure constant by regulating the engine torque. - In detail is off 2 a double-acting, a working piston 21 , a piston rod 22 and a cylinder chamber comprising piston / cylinder arrangement 20 can be seen in the reversible movable piston 21 the cylinder chamber on the one hand in a first piston chamber 23A (or working cylinder) and on the other hand into a piston rod 22 surrounding annulus 23C (or Rückholzylinder) divided. An approximately provided rapid traverse piston can, as not shown, be oriented in a direction pointing in the opposite direction to the piston rod or in the same direction as the piston rod. The piston / cylinder arrangement 20 is at a the first piston chamber 23A with a pressure medium supplying the first pressure line D1 and the annulus 23C connected with pressure medium supplying pressure line D3.

Two, each designed as drives with variable speed motors 33B and 33C drive one each, especially variable speed pump 32 respectively. 34 at. Alone the pump 33C is with a facility 50 . 51 equipped for adjusting their delivery volume. The adjustment takes place on the one hand, in particular pump-internally, by a control device, in particular in the form of an actuating cylinder 51A which changes the flow rate in a known manner following the current pressure. In addition, a hydraulic upstream adjustment (hydraulic valve) in the form of a proportional valve 50 used, which responds to hydraulic or, in particular, electrical control variables of an external control, such as in a converter U. Thus, the pump flow rate can be adjusted hydraulically depending on an external input signal up to the maximum flow rate.

The engine 33C associated pump 32 is in the present embodiment with serving as a working cylinder piston chamber 23A hydraulically connected. Both pumps 32 and 34 are on one side with a tank 40 and on the other side with the piston chamber 23A or with the annulus 23C fluidly connected. The on the piston rod 22 installed encoder 36 the current piston position signals the drive to one 33B respectively. 33C Powered inverter U.

The equipment of the two engines 33C and 30 with suitable (not shown in any of the figures, optional) brakes can be a dangerous sinking the piston 21 under the influence of gravity with vertically installed cylinder unit 20 , for example, prevent power failure. On previously used in such cases switching valves can be dispensed with.

While adjusting the at least one pump 31 ; 32 according to the preceding realization of the invention ( 1 and 2 ) is carried out via a proportional valve, according to the realizations after 3 to 7 a small, especially mechanical, drive means 62 ; 62A . 62B , preferably in the form of a servomotor, used for the adjustment operation. He acts either on another pump 61 , preferably in the form of a small gear pump, on the adjusting piston, ie on a hydromechanical drive member 51A . 51B , which is preferably designed as a positioning cylinder ( 3 ), or it acts on a mechanical drive member 51C , which is preferably designed as an adjusting spindle ( 4 to 7 ).

At the realizations after 3 to 7 There are a number of advantages (individually or jointly): For example, there is at least one pump 31 . 32 also pivotable without a pending hydraulic pressure. The energy consumption is significantly lower. The control (x motor revolutions generate y degrees pump swivel angle) is easier. A use of the targeted tilting to "0" as an observable safety function is possible. There is a possibility of fixing the pump swivel angle by a brake on the motor side. Further, it is according to all in the embodiments 1 to 7 used, electrically pivotable pumps possible to swing them beyond the zero point. It then change suction and pressure side. In this way, one can also avoid a reversal of the direction of rotation of the motor and, instead, "swivel" the pump, in particular. In this case, a simple asynchronous motor with frequency converter can be used instead of the servomotor.

At the realizations after 5 and 7 (Exemplary and insofar preferred representations) is advantageously a use of the annulus 23C supplying pump (pump 31 ) also for filling the first piston chamber 23A possible. So far, the ring and first piston chambers each had their own pump. This was necessary because both rooms have different areas. Connecting the second pressure fluid outlet 31B the annular chamber pump 31 instead of with the pressure fluid tank, via a pipe also with the first piston chamber 23A , so u. A. the different area ratios are compensated by the pumps 31 and or 32 be adapted in their funding volume to these (area ratios). This solution concept is of inherently inventive importance and also applicable to the other implementations of the invention.

Example: For a cylinder with the piston / ring area ratio of 2: 1, two identical pumps with a delivery volume of, for example, a maximum of 40 cm ^{3 would be} selected. When the piston is extended, there is a delivery volume of 40 + 40 = 80 cm ^{3 on} the piston side. The piston pump can therefore be dimensioned much smaller. By changing the swivel angle of the pump connected to the annular space, the delivery volume can be adjusted so that the pressure in the annulus assumes the desired value (eg, about 5 bar in the downward travel, 20 bar in the upward travel). Since both pumps can be pivoted independently - such. In 6 shown, the swing angle change can be realized with increasing engine utilization. Also temporary changes in the flow ratio piston / ring z. B. during the compression or decompression are compensated by pivot angle corrections. Special advantages: The pumps can be smaller in size (40 + 40 instead of 80 + 40). Noise level and power loss and pump price decrease.

In the too 6 alternative embodiment according to 7 is on a self-controlled engine for the second drive device 60B waived. Instead, it's a gearbox 63 provided that the (single) engine 62A and the associated drive member, such as an adjusting spindle, coupled to the other drive member in a, in particular fixed, speed ratio. The adjustment of, z. B. on the annulus 23C acting on, pump 31 then follows, in particular the area ratios on the working piston 21 accordingly, the adjustment of the, z. B. the first piston chamber 23A acting on, pump 32 , This solution concept is of independent inventive importance and also in the other realizations of the invention, at least after 3 to 6 , applicable.

It is important to emphasize that it is readily possible for one skilled in the art to understand the other features of the implementations 1 and 2 and the remaining features of the realizations 3 to 7 to apply essentially in each case other implementations of the invention.

LIST OF REFERENCE NUMBERS

10

drive arrangement

20

Piston / cylinder assembly

21

working piston

22

piston rod

23A

(first) piston chamber or working cylinder

23C

(second) piston chamber or annulus or Rückholzylinder

30

pump assembly

31

(first) pump

31A

(first) pressure fluid outlet

31B

(second) pressure fluid outlet

32

second pump

33

drive

33A

drive shaft

33B

drive

33C

drive

34

pump

36

encoder

37

transmission

38

adjustment

38A

adjustment

38B

adjustment

40

Pressure medium tank

50

hydraulic valve

50A, 50B

Proportional valve / e

51

actuating means

51A, 51B

hydromechanical drive element, such as actuating cylinder

51C

mechanical drive element, such as adjusting spindle

51C '

mechanical drive element, such as adjusting spindle

51C ''

mechanical drive element, such as adjusting spindle

52

Pump-swivel mechanism

60

driving means

60A

driving means

60B

driving means

61

another pump

62

drive means

63

transmission

150

signal line

150A

signal line

150B

signal line

D1

(first) pressure line

D1 '

connecting line

D3

(second) pressure line

D3 '

connecting line

U

inverter

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2010/020427 [0003, 0004, 0008]
• WO 2012/110259 [0003, 0008, 0024, 0040]

Claims (15)

Hydraulic, in particular pressure accumulatorless, drive arrangement ( 10 ) for and with a consumer, in particular for presses, with a, in particular double-acting, piston / cylinder arrangement ( 20 ), the at least one reversibly movable working piston ( 21 ) and at least one cylinder space and in which the at least one cylinder space or the cylinder spaces at least one of the working piston ( 21 ) acted upon by fluid pressure, the first piston chamber ( 23A ), and, preferably, at least one second piston space ( 23C ), comprising pressure line (s) (D1, D3) supplying pressure fluid to the piston chamber (s) (s) (D1, D3), with at least one pump arrangement ( 30 ), which at least one, preferably at least variable speed driven pump ( 31 ; 32 ) and at least one the at least one pump ( 31 . 32 ) driving, preferably variable speed, drive ( 33 ), with at least one of the piston / cylinder arrangement ( 20 ) and the pump assembly ( 30 ) hydraulically connected or connectable pressure medium supply, wherein the at least one pump ( 32 ) via a first pressure line (D1) with the first piston chamber ( 23A ) is connected or connectable, so that the hydraulic drive arrangement ( 10 ), preferably by means of a single single-motor drive train, can be operated in at least one direction of movement and, preferably, also reaches high working pressures during operation, characterized by at least one hydromechanical actuating cylinder ( 51 ; 51A ) of the at least one pump ( 32 ), a hydraulic connection / connection line (D1 '), which between the actuating cylinder ( 51 ; 51A ) and between the at least one pump ( 32 ) and its associated piston chamber ( 23A ) provided pressure line (D1) is effective, and at least one hydraulic valve, in particular a proportional valve ( 50 ; 50A ), wherein the at least one hydraulic valve in the at least one connecting line (D1 ') between the actuating cylinder ( 51 ; 51A ) and the pressure line (D1) is hydraulically effective such that by varying the position of this hydraulic valve by means of an external, in particular electrical, the position of the hydraulic valve influencing actuating signal of the actuating cylinder ( 51 ; 51A ) can be acted upon by a variable pressure. Hydraulic drive arrangement ( 10 ) according to claim 1, characterized in that an adjusting device ( 38 ) of the at least one pump and an actuating means ( 51 ) are provided for this, wherein the flow of the at least one pump by means of the actuating means ( 51 ) actuatable adjusting device ( 38 ) is changeable. Drive arrangement according to Claim 1 or 2, characterized by at least two, each of at least one pump ( 32 ; 34 ) and a drive ( 33C ; 33B ), separate motor pump stations for the first piston chamber ( 23A ) and for at least one second piston space ( 23C ), wherein at least one of the motor pump stations is a hydraulic valve ( 50 ) in the connecting line between the actuating cylinder ( 51 ) and the associated pressure line. Method for operating a hydraulic, in particular accumulatorless, drive arrangement for a consumer, in particular for pressing, with one, in particular double-acting, at least one reversibly movable working piston ( 21 ) and at least one cylinder chamber comprising piston / cylinder arrangement ( 20 ), wherein the at least one cylinder space or the cylinder spaces at least one of the working piston ( 21 ) acted upon by fluid pressure, the first piston chamber ( 23A ), and, preferably, at least one second piston space ( 23C ) comprising, with the piston chambers with a pressure medium supplying pressure lines (D1, D3), with at least one pump arrangement ( 30 ), which at least one, preferably at least variable speed driven pump ( 31 ; 32 ) and at least one the at least one pump ( 31 . 32 ) driving, preferably variable speed, drive ( 33 ), in particular if an adjusting device ( 38 ) of the at least one pump and an actuating means ( 51 ) is provided for this, wherein the flow rate of the at least one pump by means of the actuating means ( 51 ) actuatable adjusting device ( 38 ) is variable with at least one with the piston / cylinder arrangement ( 20 ) and the pump assembly ( 30 ) hydraulically connected or connectable pressure medium supply, wherein the at least one pump ( 32 ) via a first pressure line (D1) with the first piston chamber ( 23A ) is connected or connectable, so that the hydraulic drive arrangement ( 10 ), preferably by means of a single single-motor drive train, can be operated in at least one direction of movement and, preferably, also reaches high working pressures during operation, characterized in that at least one hydromechanical actuating cylinder ( 51 ; 51A ) of the at least one pump ( 32 ) is provided, a hydraulic connection / connecting line (D1 ') between the actuating cylinder ( 51 ; 51A ) and between the at least one pump ( 32 ) and its associated piston chamber ( 23A ) provided pressure line (D1) is effective, is provided, and at least one hydraulic valve, in particular a proportional valve ( 50 ; 50A ) is provided, wherein the at least one hydraulic valve in the at least one connecting line (D1 ') between the actuating cylinder ( 51 ; 51A ) and the pressure line (D1) is so hydraulically effective that by varying the position of this hydraulic valve by means of an external, in particular electrical, the position of the hydraulic valve influencing actuating signal of the actuating cylinder ( 51 ; 51A ) is subjected to a variable pressure. Method according to the preamble of claim 4, in particular according to claim 4, characterized in that caused by a hydromechanical or mechanical pump adjustment or regulation change, in particular reduction, of the flow of the at least one pump by means of a hydromechanical or mechanical pump adjustment causing or the pump control overlaid, externally controllable hydraulic or mechanical drive device ( 60 ) is delayed until the drive torque of the engine is utilized as much as desired. A method according to claim 4 or 5, characterized in that the drive motor of the variable-speed hydraulic drive by means of externally controllable drive means ( 60 ) is briefly deliberately loaded beyond its rated torque. Method according to one of claims 4 to 6, characterized by using the current load factor of the drive motor as a controlled variable for the pump to be ordered. A method according to claim 6 or 7, characterized in that for re-cooling the previously deliberately overloaded Antiebsmotors a rapid traverse and / or pauses are used for loading and unloading of the consumer. Method according to one of claims 4 to 8, characterized in that a high tilt angle of the at least one pump is maintained, although the course of the load factor indicates a speedy emergency shutdown. Hydraulic, in particular pressure accumulatorless, drive arrangement ( 10 ) for and with a consumer, in particular for presses, with a piston / cylinder arrangement ( 20 ), the at least one reversibly movable working piston ( 21 ) and at least one cylinder space and in which the at least one cylinder space or the cylinder spaces at least one of the working piston ( 21 ) acted upon with fluid pressure (first) piston chamber ( 23A ), comprising / comprising pressure line (s) (D1, D3) supplying pressure medium to the piston chamber (s) with at least one pump arrangement ( 30 ), which at least one, preferably at least variable speed driven pump ( 31 ; 32 ) and at least one the at least one pump ( 31 . 32 ) driving, preferably variable speed, drive ( 33 ), with an adjusting device ( 38 ) of the at least one pump and an actuating means ( 51 ), wherein the flow rate of the at least one pump by means of the actuating means ( 51 ) actuatable adjusting device ( 38 ) is variable with at least one with the piston / cylinder arrangement ( 20 ) and / or the pump arrangement ( 30 ) hydraulically connected or connectable pressure medium supply, wherein the at least one pump ( 32 ) via a first pressure line (D1) with the (first) piston chamber ( 23A ) is connected or connectable, so that the hydraulic drive arrangement ( 10 ) is operable in at least one direction of movement and, preferably, also in the operation reaches the desired working pressures, characterized in that the drive arrangement ( 10 ) as adjusting means ( 51 ) of the at least one pump ( 32 ) at least one hydromechanical or mechanical drive member, such as a control cylinder ( 51A ; 51B ) or an adjusting spindle ( 51C ), and that at least one, preferably external, in particular electrically controlled, drive device ( 60 ) for varying the position of the actuating means ( 51 ) of the adjusting device ( 38 ) of the at least one pump is provided. Hydraulic drive arrangement according to Claim 10, in which the actuating means ( 51 ) of the at least one pump ( 32 ) at least one hydromechanical drive member, such as a control cylinder ( 51A ; 51B ), characterized in that the at least one drive device ( 60 ) comprises: a) a hydraulic connection / connection line (D1 ';D3') connected between the actuating cylinder ( 51A ; 51B ) and between the at least one pump ( 32 ) and its associated piston chamber ( 23A ) provided pressure line (D1) is effective, and b) at least one hydraulic valve ( 50 ), in particular a proportional valve ( 50A ; 50B ), and that the at least one hydraulic valve in the at least one connecting line (D1 ') between the Adjusting cylinder ( 51 ; 51A ) and the pressure line (D1) is hydraulically effective such that by varying the position of this hydraulic valve by means of an external, in particular electrical, the position of the hydraulic valve influencing actuating signal of the actuating cylinder ( 51 ; 51A ) can be acted upon by a variable pressure. Hydraulic drive arrangement according to Claim 10, in which the actuating means ( 51 ) of the at least one pump ( 32 ) at least one hydromechanical drive member ( 51A ; 51B ), such as an actuating cylinder, characterized in that the at least one drive device ( 60 ) comprises: a) one with the hydromechanical drive member ( 51A ; 51B ) of the at least one pump ( 32 ) in Verstellsinn fluidly connected (further) pump ( 61 ) and b) one of the other pumps ( 61 ) associated drive means ( 62 ), and that by controlling the drive means ( 62 ) by means of an external, in particular electrical, the delivery rate of the further pump ( 61 ) influencing control signal the hydromechanical drive member ( 51A ; 51B ) is displaceable in variable positions. Hydraulic drive arrangement according to Claim 10, in which the actuating means ( 51 ) of the at least one pump ( 32 ) at least one mechanical drive member ( 51C ), such as an adjusting spindle, characterized in that the at least one drive device ( 60 ) with the mechanical drive member ( 51C ) of the at least one pump ( 32 ) in the sense of adjustment connected drive means ( 62 ) and that by controlling the drive means ( 62 ) by means of an external, in particular electrical, the position of the mechanical drive member ( 51C ) affecting the mechanical drive element ( 51C ) is displaceable in variable drive positions. Hydraulic drive arrangement according to one of claims 10 to 13, wherein the piston / cylinder arrangement ( 20 ) at least one (second) piston space ( 23C ) from a (first) pump ( 31 ) of the pump assembly ( 30 ), characterized in that the (first) pump ( 31 ) via a second pressure fluid outlet ( 31B ) with the (first) piston chamber ( 23A ) of the piston / cylinder arrangement ( 20 ) is connected or connectable to its additional pressurizing agent. Hydraulic drive arrangement according to one of claims 10 to 14, wherein the piston / cylinder arrangement ( 20 ) at least one (second) piston space ( 23C ) from a (first) pump ( 31 ) of the pump assembly ( 30 ) is fed, characterized in that, waiving a self-controlled drive means for a second drive means ( 60B ), a transmission ( 63 ) is provided that the drive means of the associated drive member of the first drive means ( 60A ) Coupled with the other drive member in one, in particular fixed, speed ratio.

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