Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
  • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
  • F15B11/024—Systems essentially incorporating special features for controlling the speed or actuating force of an output member by means of differential connection of the servomotor lines, e.g. regenerative circuits
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B30—PRESSES
  • B30B—PRESSES IN GENERAL
  • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
  • B30B15/16—Control arrangements for fluid-driven presses
  • B30B15/161—Control arrangements for fluid-driven presses controlling the ram speed and ram pressure, e.g. fast approach speed at low pressure, low pressing speed at high pressure
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2211/00—Circuits for servomotor systems
  • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
  • F15B2211/205—Systems with pumps
  • F15B2211/20507—Type of prime mover
  • F15B2211/20515—Electric motor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2211/00—Circuits for servomotor systems
  • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
  • F15B2211/205—Systems with pumps
  • F15B2211/2053—Type of pump
  • F15B2211/20561—Type of pump reversible
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2211/00—Circuits for servomotor systems
  • F15B2211/30—Directional control
  • F15B2211/305—Directional control characterised by the type of valves
  • F15B2211/3056—Assemblies of multiple valves
  • F15B2211/30565—Assemblies of multiple valves having multiple valves for a single output member, e.g. for creating higher valve function by use of multiple valves like two 2/2-valves replacing a 5/3-valve
  • F15B2211/3058—Assemblies of multiple valves having multiple valves for a single output member, e.g. for creating higher valve function by use of multiple valves like two 2/2-valves replacing a 5/3-valve having additional valves for interconnecting the fluid chambers of a double-acting actuator, e.g. for regeneration mode or for floating mode
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2211/00—Circuits for servomotor systems
  • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
  • F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
  • F15B2211/7051—Linear output members
  • F15B2211/7053—Double-acting output members
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2211/00—Circuits for servomotor systems
  • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
  • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
  • F15B2211/7107—Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being mechanically linked
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2211/00—Circuits for servomotor systems
  • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
  • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
  • F15B2211/7114—Multiple output members, e.g. multiple hydraulic motors or cylinders with direct connection between the chambers of different actuators
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2211/00—Circuits for servomotor systems
  • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
  • F15B2211/775—Combined control, e.g. control of speed and force for providing a high speed approach stroke with low force followed by a low speed working stroke with high force, e.g. for a hydraulic press
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2211/00—Circuits for servomotor systems
  • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
  • F15B2211/78—Control of multiple output members
  • F15B2211/782—Concurrent control, e.g. synchronisation of two or more actuators
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2211/00—Circuits for servomotor systems
  • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
  • F15B2211/785—Compensation of the difference in flow rate in closed fluid circuits using differential actuators

Definitions

• the present invention generally relates to a hydraulic drive preferably for a press, plastic machine, bending machine, etc. according to the preamble of claim 1.
• Such drives are designed to at least two movements, namely a fast transfer movement (hereinafter referred to as “rapid traverse") and a force applying work movement (hereinafter referred to as "press gear”) to realize.
• a generic hydraulic drive for a press is known.
• This drive consists of a driven hydrostatic machine that generates a predetermined constant pressure in a primary pressure line system and a hydraulic transformer consisting of a hydraulic motor and a hydraulic pump connected to it mechanically.
• the preferably adjustable hydraulic motor is connected to the primary pressure line system and is thus driven by the hydrostatic machine.
• the also adjustable hydraulic pump acts on a secondary pressure line system with a
• Hydraulic pressure in which a press cylinder is used, whose cylinder chambers are connected via valves to the two hydraulic connections of the hydraulic pump. Finally, the two cylinder chambers of the press cylinder are connected via a pressure line to the primary pressure line system to bias the plunger to the primary pressure (corresponding to the required bias pressure for the press cylinder).
• Invention is to provide a generic hydraulic drive, which manages with a reduced number of hydraulic components and is characterized in operation by a low energy consumption.
• the invention accordingly relates to a hydraulic drive with a variable speed controlled by an electric drive motor hydraulic machine, a master cylinder for performing a force-building movement sequence and a slave cylinder to perform a fast movement.
• the master cylinder is through one, preferably both
• Piston surfaces acting further preferably pre-clamped or clamped by an external pressure source generated predetermined permanent pressure, wherein the
• Movements are responsible hydraulic machine or by the external
• FIG. 1 is a schematic diagram of a hydraulic drive according to a preferred embodiment of the invention at a standstill (under bias),
• FIG. 2 shows the schematic diagram of the hydraulic drive according to FIG. 1 in "rapid traverse” downwards
• FIG. 3 shows the block diagram of the hydraulic drive according to FIG. 1 in the "press gear"
• Fig. 4 shows the block diagram of the hydraulic drive of FIG. 1 in a Re-compression phase
• Fig. 5 shows the schematic diagram of the hydraulic drive of FIG. 1 in the "rapid" up (retraction phase).
• the inventive hydraulic drive a pressure medium source in the form of a variable speed driven hydraulic machine 1 as a pump, which is mechanically connected thereto for an electric motor 2.
• the hydraulic machine 1 is at its two
• Pressure ports connected to a hydraulic pressure line system, which forms a closed hydraulic pressure circuit.
• a first connection line 3 is connected to a first pressure connection of the hydraulic machine 1, which leads directly to a piston side
• Pressure chamber 4a of a master cylinder 4 leads.
• a second line 5 is connected, which is connected via a valve 6 with a piston rod-side pressure chamber 4b of the master cylinder 4 (hereinafter referred to as annular chamber 4b).
• the valve 6 is present as a
• Directional control valve and in particular as a 3/2 way switching valve formed with a first switching position, in which only a hydraulic fluid flow from the
• Annular chamber 4b of the master cylinder 4 is allowed in the direction of hydraulic machine 1, a second switching position in which a hydraulic fluid flow in both directions is possible and a third switching position in which the second line 5 is completely locked.
• a branch 7 is inserted into the second line 5, which leads to a
• piston rod side pressure chamber 8a of an auxiliary cylinder 8 leads.
• the piston 8b of the auxiliary cylinder 8 is in its diameter significantly smaller than the piston 4c of the master cylinder 4, so that the stroke of the auxiliary cylinder 8 at a comparable volume flow of the hydraulic fluid is greater than the stroke of the
• the ring sides of the cylinders 4, 8 ideally have in sum the same area as the piston side of the master cylinder 4.
• a bypass or shorting line 9 which connects the piston chamber 4a of the master cylinder 4 with the annular chamber 4b.
• a short-circuit valve 10 is interposed, the in the present case designed as a way switching valve and preferably as a 2/2 way switching valve.
• the bypass line 9 In a first switching position of this short-circuit valve 10, the bypass line 9 is fully open (ie in both directions), wherein in a second switching position only a fluid flow from the annular chamber 4b is admitted into the piston chamber 4a of the master cylinder 4 via the bypass line 9.
• the hydraulic drive with the above structure is installed in a press.
• the piston rod 4d of the master cylinder 4 as well as the piston rod 8c of the slave cylinder 8 are connected to a displaceably mounted ram 11 to which a pressing tool 12 or a punching tool is attached.
• the hydraulic pressure system according to the invention also has numerous safety devices to prevent overpressure conditions or unintentional lowering of the ram 11, which are not shown in detail in the figures.
• the annular chamber 8a of the auxiliary cylinder 8 can be secured via two series-monitored, monitored seat valves (not shown). Thereby, a lowering of the upper pressing tool 12 can be securely prevented.
• the piston chamber 4 a of the master cylinder 4 can be secured against unintentional pressurization. This can be achieved by the shown directional valves 6, 10 itself, or by a supervised release of the
• a pressure accumulator 13 is connected via a valve 14 to the first pressure line 3 between the hydraulic machine 1 and the piston chamber 4a of the master cylinder 4.
• This valve 14 is provided by a directional control valve, preferably a 2/2 way switching valve, with a first switching position in which the connection between the external pressure source 13 and the first pressure line 3 is fully released and a second switching position in which only a fluid flow the external pressure source 13 in the first pressure line 3 is allowed.
• Pressure medium source with a predetermined approximately constant (in particular regulated) hydraulic pressure applied.
• the movement of the two cylinders 4, 8 is controlled by circulating pressure medium in the closed pressure circuit by means of the variable-speed driven hydraulic machine 1.
• Movement of the working stroke of the press with participation of both cylinders by means of the valves 6, 10 and the variable speed driven (constant) pump can be controlled.
• the switching-off valve 6 when the hydraulic drive is at a standstill (in the retracted position of the ram 11), the switching-off valve 6 is in that switching position in which only one fluid flow out of the annular chamber 4b of the
• the slave cylinder 8 is smaller than the master cylinder 4 and the pump 1 acts only on the volume of the ring side of the slave cylinder 8, the downward movement (and later the retraction movement) of the ram 11 at a predetermined volume flow at a relatively high speed, even then, if the
• Hydromachine 1 is designed with a small capacity. In addition, by briefly overloading the electric drive motor 2 (permissible), the speed but also the subsequent pressing force can be further increased.
• the short-circuit valve 10 switches to the switching position in which only one flow from the annular chamber 4b of the master cylinder 4 is allowed and the valve 6 in the switching position in which a fluid flow from the annular chamber 4b to Hydromachine 1 is allowed.
• the pressure within the annular chamber 4 b is now reduced by the hydraulic machine 1, since no pressure equalization between the master cylinder chambers 4 a, 4 b on the
• Short circuit valve 10 takes place more, whereas the pressure within the
• Piston chamber 4a of the master cylinder 4 is maintained or increased. That is, instead of a considerable compression of the piston side of the master cylinder 4, the actual pressing force is generated by pressure release of the ring sides of the cylinders 4, 8. Since no pressure equalization takes place between the main cylinder chambers 4a, 4b, furthermore, the continuous pressing movement of the master cylinder 4 at a constant volumetric flow decreases significantly to a lowering movement
• valve 6 is brought into a switching position according to FIG. 4, after which a fluid flow within the connecting line 5 in both directions, ie from and to the annular chamber 4b of the master cylinder 4 is made possible. In this case, a pressure equalization between the
• the plunger 11 can be retracted by, as shown in Fig. 5, the valve 6 is brought into the switching position, in the only one
• the hydraulic machine 1 can be flanged to a valve block (not shown), which the
• Function or safety valves of the drive contains.
• the electric motor for operating the pump can be attached to these.
• This unit can in turn be constructed on a hydraulic cylinder, whereby a particularly compact Anstriebsachse is available. LIST OF REFERENCES

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• General Engineering & Computer Science (AREA)
• Control Of Presses (AREA)
• Fluid-Pressure Circuits (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

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ID=43087109

Family Applications (1)

Country Status (5)

Cited By (2)

Families Citing this family (15)

Citations (2)

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• 2009
  • 2009-09-25 DE DE200910043034 patent/DE102009043034A1/de active Pending
• 2010
  • 2010-07-27 CN CN201080042771.7A patent/CN102612430B/zh active Active
  • 2010-07-27 WO PCT/EP2010/004578 patent/WO2011035828A1/de active Application Filing
  • 2010-07-27 EP EP10740535.9A patent/EP2480405B1/de not_active Revoked
  • 2010-09-23 TW TW099132124A patent/TWI519717B/zh active

Patent Citations (3)

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