EP3770445A1 - Vérin pneumatique ou hydraulique - Google Patents

Vérin pneumatique ou hydraulique Download PDF

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Publication number
EP3770445A1
EP3770445A1 EP19187881.8A EP19187881A EP3770445A1 EP 3770445 A1 EP3770445 A1 EP 3770445A1 EP 19187881 A EP19187881 A EP 19187881A EP 3770445 A1 EP3770445 A1 EP 3770445A1
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EP
European Patent Office
Prior art keywords
pressure
pressure chamber
piston rod
cylinder
piston
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP19187881.8A
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German (de)
English (en)
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EP3770445B1 (fr
Inventor
Marc Tellen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beumer Group GmbH and Co KG
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Beumer Group GmbH and Co KG
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Filing date
Publication date
Application filed by Beumer Group GmbH and Co KG filed Critical Beumer Group GmbH and Co KG
Priority to EP19187881.8A priority Critical patent/EP3770445B1/fr
Priority to ES19187881T priority patent/ES2919566T3/es
Priority to PCT/DE2020/100590 priority patent/WO2021013295A1/fr
Publication of EP3770445A1 publication Critical patent/EP3770445A1/fr
Application granted granted Critical
Publication of EP3770445B1 publication Critical patent/EP3770445B1/fr
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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    • 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
    • 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
    • F15B11/028—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force
    • 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
    • F15B11/028—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force
    • F15B11/036—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force by means of servomotors having a plurality of working chambers
    • 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
    • F15B11/028—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force
    • F15B11/036—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force by means of servomotors having a plurality of working chambers
    • F15B11/0365—Tandem constructions
    • 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
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08—Characterised by the construction of the motor unit
    • F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/17—Characterised by the construction of the motor unit of the straight-cylinder type of differential-piston type
    • 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
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/204—Control means for piston speed or actuating force without external control, e.g. control valve inside the piston
    • 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
    • F15B20/00—Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
    • 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
    • F15B2011/0243—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 the regenerative circuit being activated or deactivated automatically
    • 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
    • F15B2211/30505—Non-return valves, i.e. check valves
    • 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
    • F15B2211/3057—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 two valves, one for each port of a double-acting output member
    • 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
    • F15B2211/40—Flow control
    • F15B2211/415—Flow control characterised by the connections of the flow control means in the circuit
    • F15B2211/41527—Flow control characterised by the connections of the flow control means in the circuit being connected to an output member and a directional control valve
    • F15B2211/41536—Flow control characterised by the connections of the flow control means in the circuit being connected to an output member and a directional control valve being connected to multiple ports of an output member
    • 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
    • F15B2211/705—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
    • F15B2211/7055—Linear output members having more than two chambers
    • 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
    • F15B2211/7055—Linear output members having more than two chambers
    • F15B2211/7056—Tandem cylinders
    • 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
    • F15B2211/76—Control of force or torque of the output member
    • 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
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/86—Control during or prevention of abnormal conditions
    • F15B2211/8643—Control during or prevention of abnormal conditions the abnormal condition being a human failure
    • 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
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/875—Control measures for coping with failures
    • F15B2211/8757—Control measures for coping with failures using redundant components or assemblies

Definitions

  • the invention is based on a pneumatic or hydraulic piston rod cylinder with a cylinder and a piston adjustable in its longitudinal direction, which is coupled to a piston rod protruding from the cylinder and a volume accommodated in the cylinder in a first pressure chamber through which the piston rod extends , and subdivided a second pressure chamber, the pressure chambers being fluidically connected to one another via a bypass and each having a pressure connection, which can optionally also be formed in a cylinder wall of the cylinder and via which the pressure chambers can be acted upon with a fluid, and with a first side of the piston, the first pressure chamber and a second side, which is arranged opposite the first side and has a larger area than the first side, delimits the second pressure chamber.
  • a piston rod cylinder is from DE 2 061 883 A known. Similar piston rod cylinders also describe the DE 10 2006 041 707 B4 and the DE 10 2012 007 170 B3 .
  • the known piston rod cylinders have the disadvantage that the design of the bypass is structurally complex, for example in that the bypass is ensured by a recess in the cylinder.
  • the bore diameter of the cylinder can be made larger in sections than the diameter of the piston, so that the fluid can flow around the piston in this section.
  • This design also has the disadvantage that it is impossible to install additional functional components, for example the installation of valves in the bypass.
  • solutions are known in which the bypass is formed within the piston rod so that the connection points for the bypass are moved with the piston and are interrupted by moving a connection point out of the compressed pressure chamber into another chamber of the bypass. This design is also complex in terms of construction.
  • first and the second pressure chamber are fluidically connected to one another via a bypass line of the bypass that is connected to the pressure connections of the pressure chambers.
  • bypass line is arranged and / or guided outside the cylinder at least over part of its length and preferably over its entire length.
  • the bypass line can have a unidirectionally permeable valve, preferably a check valve, which is permeable in the direction of fluid flow from the second pressure chamber to the first pressure chamber and is impermeable in the opposite direction.
  • bypass line and / or the unidirectionally permeable valve can be formed at least partially and preferably completely in a wall of the cylinder.
  • the pressure connection need not necessarily be led to the outside.
  • the bypass line can be connected to the second pressure chamber via the pressure connection of the second pressure chamber.
  • the bypass line can be connected to the first pressure chamber via the pressure connection of the first pressure chamber.
  • the piston can have a lower stop position which corresponds to an end point of movement of the piston at which the piston rod protrudes from the cylinder by a maximum length.
  • a sealing circumference of the piston via which the piston rests in a sealing manner on the inner circumference of the cylinder, can close the pressure connection of the first pressure chamber, via which the bypass line is connected to the first pressure chamber.
  • the pressure connection of the first pressure chamber can be closed in such a way that the sealing circumference of the piston passes over the pressure connection shortly before reaching the lower stop position and then continuously until reaching the lower stop position.
  • the first pressure chamber can have a minimum volume into which a further pressure connection opens into the first pressure chamber.
  • the further pressure connection can be provided in order to move the piston out of the stop position after the stop position has been reached by applying pressure to the first pressure chamber, so that the volume of the first pressure chamber increases and the volume of the second pressure chamber decreases.
  • the sealing circumference of the piston can close the pressure connection of the bypass line, which opens into the first pressure chamber, without interruption by an adjustment path of the piston that ends in the stop position and is thus immediately upstream of the stop position.
  • This adjustment path can for example be up to 10 mm, preferably up to 8 mm and particularly preferably up to or exactly 4 mm and determined by the dimensions of the sealing circumference in the longitudinal direction or smaller than this dimension.
  • the bypass line can have at least two sub-lines interconnected in parallel, each having a unidirectionally permeable valve, preferably a check valve, which are permeable in the direction from the second pressure chamber to the first pressure chamber.
  • the area of the second side can correspond to the cross-sectional area of the cylinder perpendicular to the longitudinal direction, the area of the first side being less than the area of the second side by a cross-sectional area of the piston rod.
  • the difference in area between the two sides of the piston can cause a maximum force of 150 N and particularly preferably a maximum of 135 N acting on the piston at a given pressure.
  • a piston rod cylinder which is pneumatically or hydraulically driven and divides a cylinder into two pressure chambers, each of which has a pressure connection.
  • the first pressure chamber can have a further pressure connection in order to retract the piston, which has been maximally or partially extended from the cylinder, back into the cylinder. Since the two pressure chambers are fluidically connected to one another via the bypass line, essentially the same pressure is present in them. Since in the first pressure chamber the Piston rod is arranged, the pressurized area of the piston on the side of the first pressure chamber is smaller than on the side of the second pressure chamber. As a result, the piston is displaced at the same pressure in the first and the second pressure chamber in such a way that the volume of the first pressure chamber is reduced and that of the second pressure chamber is increased.
  • the pressure connection of the first pressure chamber can be arranged somewhat above the end point of movement of the piston, for example by 4 mm.
  • the piston passes the pressure connection of the bypass line of the first pressure chamber and closes it, the two pressure chambers are no longer connected to one another via the bypass line, so that pressure is not applied to the pressure connection of the first pressure chamber. This increases the force effectively acting on the piston and the piston is pressed in the direction of the first pressure chamber.
  • the first pressure chamber can be pressurized via a further pressure connection which is arranged outside the range of movement of the piston in the cylinder, for example below or above the end point of movement of the piston.
  • the piston can be moved in a first movement section with a low feed force, so that there is no risk of injury, for example by pinching a finger, and in a second movement section with an increased feed force.
  • Appropriately driven piston rod cylinders can be used, for example, in sack holding cylinders or welding tongs for ultrasonic welding.
  • the Figure 1 shows a schematic representation of a first embodiment of a piston rod cylinder 1 according to the invention.
  • the piston rod cylinder 1 has a cylinder 2 which has an essentially constant cross section over its entire height and is therefore simple and inexpensive to provide.
  • a piston 3 is arranged to be adjustable in the longitudinal direction of the cylinder 2, the piston 3 with its sealing circumference 12 lying fluidically sealing against the inner circumference 13 of the cylinder 2 and thus the volume inside the cylinder 2 in two fluidically separated pressure chambers 5 , 6 divided.
  • the first pressure chamber 5 is subjected to a fluid pressure or optionally vented.
  • pressurization of both the first pressure chamber 5 and the second pressure chamber 6 is provided via a second valve 18, a second pressure connection line 20 and pressure connections 15.
  • the lowermost pressure connection 16, which is connected via the first valve 17, is arranged below a lower stop position of the piston sealing circumference 12, so that in this lower stop position the piston sealing circumference 12 does not close the pressure connection 16 and thus for the pressurization of the first pressure chamber 5 Available.
  • the piston 3 with its sealing circumference 12 closes the lower pressure connection 15, which is connected to the second valve 18 via the pressure line 20, in the lower stop position and by an upstream adjustment path x, here 4 mm.
  • a bypass line 10 which connects the pressure connections 15 to one another and is routed outside of the cylinder 2, ensures that in the first and the The second pressure chamber 5, 6 always has the same pressure when the piston 3 is arranged with its circumferential sealing surface between the two pressure connections 15 and in particular does not close the lower pressure connection 15 connected to the second valve 18.
  • the bypass line 10 has two sub-lines 14 which run parallel to one another and in each of which a check valve 11 is arranged, so that redundancy is established with regard to the function of the check valves 11.
  • the check valves 11 are permeable in the direction from the second pressure chamber 6 to the first pressure chamber 5 and are blocking in the opposite direction.
  • the pressure connection 16, via which the first pressure connection line 19 is connected to the first pressure chamber, is arranged by an adjustment path x below the pressure connection 15 of the second pressure connection line 20 opening into the first pressure chamber 5.
  • the adjustment path x is preferably 4 mm.
  • FIG Figure 1 To remove the piston 3 of the piston rod 4 from the cylinder 2 from a retracted position, as shown, for example, in FIG Figure 1 is shown to be transferred into an extended position, in which, based on the representation according to FIG Figure 1 the piston 3 is vertically displaced further down in the cylinder 2, the two valves 17, 18 each provide the same or essentially the same fluid pressure with which the first and second pressure chambers 5, 6 via the pressure connection lines 19, 20 and the Pressure connections 15, 16 are acted upon.
  • the force which acts on the piston 3 and thus on the piston rod 4 at a given air pressure can thus be adjusted via the diameter of the piston rod 4. If, for example, the aim is to keep the force acting on the piston 3 so low that fingers are avoided, for example, at a given system pressure of 6 bar, which is applied to the two chambers 5, 6 via the pressure connections 15, 16 is given, a maximum piston rod diameter of 16.9 mm can be determined to ensure a "bearable" 135 N clamping force.
  • the second chamber 6 can be subjected to increased pressure via the second valve 18 and the second pressure line 20 an increased force can be exerted on the piston 3 and the piston rod 4, as might be required depending on the application.
  • the pressure connection 15 of the bypass line 10 to the first pressure chamber 5 can be arranged so low and just above a lower stop point of the piston 3 that, for example, it is no longer possible for fingers to be trapped.
  • this last adjustment path x, over which an increased pressure can be built up on the side of the first pressure chamber 5 when the pressure connection line 15 is closed, can be only 4 mm or the like.
  • a fluid pressure can be provided via the first valve 17 and the first pressure line 19, while the second valve 18, which is connected to the second pressure chamber 6 via the second pressure connection line and the pressure connection 15, is enabled , so that when the piston 3 is displaced upwards in the vertical direction, the volume of the second pressure chamber 6 being reduced, pressure compensation can be provided by fluid discharge via the second pressure connection line 20 and the second valve 18.
  • FIG Figure 2 Another embodiment of the invention is shown in FIG Figure 2 shown.
  • a second piston 3.2 is arranged along the same piston rod 4 in the cylinder 2 next to a first piston 3.1 at a distance therefrom.
  • the pistons 3.1, 3.2 are again similar to the embodiment according to FIG Figure 1 along their respective outer circumference sealingly on the inner circumference of the cylinder 2, so that they subdivide the fluid volume accommodated in the interior of the cylinder 2.
  • lower piston 3.1 separates a first pressure chamber 5 from a second pressure chamber 6, while the second piston 3.2 separates a third pressure chamber 21 from a fourth pressure chamber 22.
  • the third pressure chamber 21 is separated from the second pressure chamber 6 in a fluid-tight manner via a separating element 23.
  • the piston rod 4 extends over the entire length of the first pressure chamber 5 through the first pressure chamber 5 and over it cylinder 2 out.
  • the piston rod 4 has a diameter which is greater than the diameter of the piston rod 4 in the area of the first pressure chamber.
  • the diameter of the piston rod 4 is essentially constant, but it can also have a diameter that varies between the second pressure chamber 6 and the fourth pressure chamber 22 in its longitudinal direction.
  • the piston rod 4 has a different diameter compared to the first and second pressure chambers 5, 6, the diameter of the piston rod 4 in the second pressure chamber 6 being greater than the diameter of the piston rod 4 in the first pressure chamber 5.
  • the first pressure connection line 19 has a fluid pressure applied to it by a first valve 17 and opens into the two pressure connections 15 of the first and second pressure chambers 5, 6, which in turn are connected to one another via a bypass line 10 to maintain a constant pressure in the two chambers 5 To ensure 6 if the bypass line is not blocked over the outer circumference of the first piston element 3.1.
  • a further pressure connection 25 is arranged by a piston adjustment path x of about 4 mm vertically above the pressure connection 15 of the second pressure chamber 6, via which pressure is applied to the second pressure chamber 6 independently of the first valve 17 by a second valve 18 and a second pressure connection line 20 can be.
  • the second piston 3.2 By moving the first piston 3.1 while varying the volumes of the first and second pressure chambers 5, 6, the second piston 3.2 is also displaced at the upper end of the piston rod 4 in such a way that the volumes of the third and fourth pressure chambers 21, 22 change.
  • the fourth pressure chamber 22 is connected via a further pressure connection point 16 and an additional pressure connection line 26 to a third valve 27, via which an overpressure can be reduced by moving the second piston 3.2 upwards by activating the third valve 27, the third pressure chamber 21 has an optionally soundproofed ventilation valve 24, so that the ambient pressure always prevails in the third pressure chamber 21.
  • the valves 17, 18, 27 shown in the embodiments can be designed, for example, as 3-way valves which are connected with a first connection side to a fluid pressure source, for example to a fluid pressure line or to a compressor. With a further connection side they are connected to a pressureless fluid volume, that is to say, for example, to the ambient air if the fluid is air.
  • the third valve connection side can then in each case be connected to one of the pressure connection lines 19, 20, 26 in order to provide the fluid pressure at the corresponding pressure connections 15, 16, 25 or to achieve pressure equalization, if necessary.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Actuator (AREA)
  • Load-Engaging Elements For Cranes (AREA)
  • Forklifts And Lifting Vehicles (AREA)
EP19187881.8A 2019-07-23 2019-07-23 Arrangement avec un vérin pneumatique ou hydraulique Active EP3770445B1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP19187881.8A EP3770445B1 (fr) 2019-07-23 2019-07-23 Arrangement avec un vérin pneumatique ou hydraulique
ES19187881T ES2919566T3 (es) 2019-07-23 2019-07-23 Disposición con cilindro de vástago de pistón neumático o hidráulico
PCT/DE2020/100590 WO2021013295A1 (fr) 2019-07-23 2020-07-03 Cylindre de tige de piston pneumatique ou hydraulique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP19187881.8A EP3770445B1 (fr) 2019-07-23 2019-07-23 Arrangement avec un vérin pneumatique ou hydraulique

Publications (2)

Publication Number Publication Date
EP3770445A1 true EP3770445A1 (fr) 2021-01-27
EP3770445B1 EP3770445B1 (fr) 2022-05-25

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EP (1) EP3770445B1 (fr)
ES (1) ES2919566T3 (fr)
WO (1) WO2021013295A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1941785A1 (de) * 1969-08-16 1971-03-04 Metrawatt Ag Fabrik Elek Scher Pneumatischer oder hydraulisch angetriebener Arbeitshubzylinder
DE2061883A1 (de) 1970-12-16 1972-06-22 Aviat Gmbh Hydraulik- oder Pneumatikarbeitszylinder
DE102006041707B4 (de) 2006-05-10 2009-01-02 Tünkers Maschinenbau Gmbh Kolben-Zylinder-Einheit (Arbeitszylinder) zum Spannen, und/oder Pressen, und/oder Fügen, und/oder Stanzen, und/oder Prägen, und/oder Lochen und/oder Schweißen, zum Beispiel unter Zwischenschaltung einer Kniehebelgelenkanordnung
DE102011009302A1 (de) * 2011-01-24 2012-07-26 Helmut Steinhilber Fluidzylinder und Pressvorrichtung
DE102012007170B3 (de) 2012-04-07 2013-08-08 Festo Ag & Co. Kg Antriebsvorrichtung
WO2013174121A1 (fr) * 2012-05-23 2013-11-28 中联重科股份有限公司 Procédé de commande d'amortissement de vérin hydraulique, système de commande de vérin hydraulique à amortissement et équipement hydraulique

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1941785A1 (de) * 1969-08-16 1971-03-04 Metrawatt Ag Fabrik Elek Scher Pneumatischer oder hydraulisch angetriebener Arbeitshubzylinder
DE2061883A1 (de) 1970-12-16 1972-06-22 Aviat Gmbh Hydraulik- oder Pneumatikarbeitszylinder
DE102006041707B4 (de) 2006-05-10 2009-01-02 Tünkers Maschinenbau Gmbh Kolben-Zylinder-Einheit (Arbeitszylinder) zum Spannen, und/oder Pressen, und/oder Fügen, und/oder Stanzen, und/oder Prägen, und/oder Lochen und/oder Schweißen, zum Beispiel unter Zwischenschaltung einer Kniehebelgelenkanordnung
DE102011009302A1 (de) * 2011-01-24 2012-07-26 Helmut Steinhilber Fluidzylinder und Pressvorrichtung
DE102012007170B3 (de) 2012-04-07 2013-08-08 Festo Ag & Co. Kg Antriebsvorrichtung
WO2013174121A1 (fr) * 2012-05-23 2013-11-28 中联重科股份有限公司 Procédé de commande d'amortissement de vérin hydraulique, système de commande de vérin hydraulique à amortissement et équipement hydraulique

Also Published As

Publication number Publication date
EP3770445B1 (fr) 2022-05-25
WO2021013295A1 (fr) 2021-01-28
ES2919566T3 (es) 2022-07-27

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