WO2022117753A1 - Hydraulisches arbeitswerkzeug mit einrichtung zur stossdämpfung - Google Patents
Hydraulisches arbeitswerkzeug mit einrichtung zur stossdämpfung Download PDFInfo
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- WO2022117753A1 WO2022117753A1 PCT/EP2021/084030 EP2021084030W WO2022117753A1 WO 2022117753 A1 WO2022117753 A1 WO 2022117753A1 EP 2021084030 W EP2021084030 W EP 2021084030W WO 2022117753 A1 WO2022117753 A1 WO 2022117753A1
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- piston
- hydraulic cylinder
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- intermediate piston
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- 238000000034 method Methods 0.000 claims abstract description 70
- 230000014759 maintenance of location Effects 0.000 claims abstract description 6
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- 238000005520 cutting process Methods 0.000 claims description 23
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- 238000010521 absorption reaction Methods 0.000 claims description 11
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
- B25B27/00—Hand tools, specially adapted for fitting together or separating parts or objects whether or not involving some deformation, not otherwise provided for
- B25B27/02—Hand tools, specially adapted for fitting together or separating parts or objects whether or not involving some deformation, not otherwise provided for for connecting objects by press fit or detaching same
- B25B27/10—Hand tools, specially adapted for fitting together or separating parts or objects whether or not involving some deformation, not otherwise provided for for connecting objects by press fit or detaching same inserting fittings into hoses
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23D—PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR
- B23D29/00—Hand-held metal-shearing or metal-cutting devices
- B23D29/002—Hand-held metal-shearing or metal-cutting devices for cutting wire or the like
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
- B25B27/00—Hand tools, specially adapted for fitting together or separating parts or objects whether or not involving some deformation, not otherwise provided for
- B25B27/14—Hand tools, specially adapted for fitting together or separating parts or objects whether or not involving some deformation, not otherwise provided for for assembling objects other than by press fit or detaching same
- B25B27/146—Clip clamping hand tools
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25F—COMBINATION OR MULTI-PURPOSE TOOLS NOT OTHERWISE PROVIDED FOR; DETAILS OR COMPONENTS OF PORTABLE POWER-DRIVEN TOOLS NOT PARTICULARLY RELATED TO THE OPERATIONS PERFORMED AND NOT OTHERWISE PROVIDED FOR
- B25F5/00—Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for
- B25F5/005—Hydraulic driving means
Definitions
- the disclosure relates first of all to a hydraulic cylinder with a working piston that can be moved and hydraulically acted upon therein, for transmitting a working force to an object to be machined outside of the hydraulic cylinder, with the build-up of a counterforce, the working piston having an acting surface, the acting surface having a surface between the working piston and
- the loading space given to the hydraulic cylinder is limited in a working direction in which the working force is transmitted, and hydraulic fluid for moving the working piston in the working direction can act on the loading surface while enlarging the loading space in order to carry out a working process.
- the disclosure also relates to a hydraulic working tool with a working head and a working piston that can be moved in a hydraulic cylinder and hydraulically acted upon.
- the disclosure also relates to a method for shock absorption of a hydraulically actuable working piston that can be moved in a hydraulic cylinder, for the transmission of a working force to an object to be machined outside of the hydraulic cylinder, with the build-up of a counterforce, the working piston having an impinging surface, the impinging surface a between the working piston and the hydraulic cylinder given loading space limited in a working direction in which the working force is transmitted, and hydraulic fluid for movement of the working piston in the working direction onto the impingement surface while enlarging the impingement space in the impingement space.
- Hydraulic cylinders with a working piston that can be moved and acted upon hydraulically therein have already become known in various respects.
- US Pat. No. 2,863,346 A discloses a hydraulic cylinder in which two hydraulic pistons are arranged one behind the other. Both hydraulic pistons are working pistons that transmit a working force to an object outside the hydraulic cylinder.
- the second working piston in the working direction is initially, at the beginning of a working process, moved by the first working piston through direct contact.
- a pressure-dependent valve opens in the first working piston. Hydraulic medium flowing through the first working piston then moves the second working piston, filling a chamber between the first and the second working piston, so that the second working piston can also act on the object outside the hydraulic cylinder.
- the second working piston can transmit impact energy to the hydraulic cylinder via a return spring which is then compressed in a force-transmitting manner.
- WO 2018/065513 A1 discloses a hydraulic cylinder with an arm that can be moved and acted upon hydraulically.
- Beitskolben and a hydraulic working tool with a working head and a hydraulic cylinder and also a method for shock absorption of a movable in a hydraulic cylinder hydraulically actuable working piston is known.
- WO 2017/080877 A1 discloses a hydraulic cylinder or a working tool and a method for shock absorption, in which a hydraulic chamber filled with hydraulic fluid is formed downstream of the working piston in the working direction and expands during a movement of the working piston in the working direction decreases with the displacement of hydraulic fluid from this hydraulic chamber into the loading chamber. In the event of a sudden loss of the counterforce, a sudden movement of the drive piston initiated in this way in the working direction is damped by the filled hydraulic chamber.
- the disclosure deals with the task of specifying another hydraulic cylinder that is advantageous in terms of shock absorption or a working tool that is advantageous in terms of shock absorption with such a hydraulic cylinder or a method for shock absorption.
- this object is initially and essentially achieved in the subject matter of claim 1, whereby it is taken into account that the working piston can be mechanically retained when the counteracting force drops in order to prevent a further movement of the working piston, which is possible without the counteracting force dropping off the working direction when the opposing force is removed.
- the hydraulic working tool it is essential that it has a hydraulic cylinder, as described above.
- the mechanical restraint becomes effective with the sudden drop in the opposing force.
- the working piston has not yet reached a stop position, so further movement of the working piston in the working direction is still possible.
- the mechanical restraint does not permit this possible further movement, which is then very often jerky and leads to a force impact on the hydraulic cylinder and possibly a working device as a whole in which the hydraulic cylinder is located.
- Different configurations are possible for this mechanical retention, as will be explained further below.
- the process of the working piston in the working direction is practically unimpeded until the counterforce drops.
- the work process preferably a separation or cutting off, can be carried out as is known in the case of known hydraulic cylinders of this type or hydraulic working tools with a hydraulic cylinder of this type. the.
- the disadvantageous effect of a sudden movement of the working piston as a result of the omission of the counterforce, which can result in heavy loads on the hydraulic cylinder and the working tool as a whole, is significantly reduced to the point that it is no longer relevant.
- the service life of such a hydraulic cylinder or a working tool with such a hydraulic cylinder is also significantly extended if such work processes leading to stress are carried out repeatedly or often with the hydraulic cylinder or the working tool.
- the mechanical coupling which can be given in further specification between the working piston and a counter-holder in general, such as the hydraulic cylinder or between the working piston and a cylinder bottom still arranged intermediate piston, allows a preferably only short-term effective restraint.
- the retention leads to an encapsulation of hydraulic fluid in the working space between the working piston and the intermediate piston or the loading space in general, which is also preferably only effective for a short time.
- This hydraulic fluid is under very high pressure shortly before the end of a work process.
- the pressures can be 200 bar or more, up to about 600, 700 or 800 bar or even more.
- the stored energy in the event of a sudden termination of the work process means that the working piston and the intermediate piston are acted upon in opposite directions or of the working piston and the counter-holder, which cancel each other out due to the mechanical coupling.
- the mechanical retention can be achieved by a mechanical coupling between the working piston and a counter-holder.
- the counter-holder can be provided in various configurations.
- the counter-holder is an intermediate piston.
- the intermediate piston is arranged between the working piston and the hydraulic cylinder, in the working direction between the working piston and a cylinder base of the hydraulic cylinder.
- the counter-holder can also be provided by the hydraulic cylinder itself, as explained in more detail below.
- the intermediate piston prefferably be arranged in front of the working piston in the working direction, for the pressure chamber to be divided by the intermediate piston into an antechamber and a working chamber, with the antechamber being located between the cylinder base and the intermediate piston and the working space is formed between the working piston and the intermediate piston, so that hydraulic fluid can flow from the antechamber into the working space while enlarging the working space, and that a mechanical coupling between the working piston and the intermediate piston causes one of the hydraulic fluid in the working space to flow out the counterforce outgoing impact can be compensated.
- the intermediate piston is arranged in the working direction in front of the working piston in the manner already described, that the loading space is divided by the intermediate piston into an antechamber and a working space , wherein the vestibule is located between the cylinder base and the intermediate piston and the working space between the working piston and the intermediate piston and that further hydraulic fluid is passed from the vestibule into the working space, increasing the working space when carrying out a work process.
- a mechanical coupling between the working piston and the intermediate piston prevents these pistons from moving away from one another.
- the intermediate piston is, as it were, only freely suspended in the hydraulic cylinder, with the exception of the mechanical coupling, which is provided at least at the end of the work process, with regard to a relative movement to the working piston in the direction of the cylinder base.
- the intermediate piston can have a coupling extension for interaction with a coupling stop of the working piston.
- This coupling extension can be designed in different ways. It can initially be a shoulder-like extension, which can meet a step-like enlargement of the working piston behind it. But it can also be a threaded part, for example with a very large thread pitch, for example as in a drill, act, which is received in a corresponding threaded opening of the working piston. At the start of a work process, when the work space is enlarged by pumping hydraulic fluid into the work space, this can lead to a rotary movement of the intermediate piston in this embodiment.
- the sudden relaxation at the end of the working process then leads to the tendency of a sudden movement in the sense of a distance from each other with respect to the intermediate piston and the working piston.
- This tendency to an abrupt movement causes a preferably short-term, momentary blockage between the threaded extension of the intermediate piston and the threaded receptacle of the working piston, not least because of the inertia of the intermediate piston, which is then to be displaced in an opposite direction of rotation.
- This also makes it possible to achieve a desired, as it were, rigid coupling between the intermediate pistons at the time when the working process is suddenly ended. This can advantageously be achieved independently of a relative distance between the working piston and the intermediate piston in the course of a working process.
- the coupling extension in the sense of a shoulder and the counter stop in the sense of a stage it is necessary in order to achieve the desired effect that the system is in place before the work process is completed.
- the minimum traversing path is selected in such a way that it is significantly shorter than the traversing path typically achieved when the work process is completed.
- the travel distance that is typically reached at the end of a travel distance can correspond to 80 to 90 percent of a maximum travel distance.
- the minimum travel can be, for example, between 40 and 70 percent of the maximum travel.
- the working piston can preferably still move further in the working direction. In this case, it then moves together with the intermediate piston. In this case, the working piston and the intermediate piston move synchronously with one another in the working direction once the minimum displacement path has been reached.
- the coupling extension can pass through the acting surface of the working piston.
- the stop means can be designed accordingly inside the working piston.
- the working piston can have an opening, preferably in the manner of a blind bore, into which an extension of the intermediate piston extends.
- the extension can have the stop shoulder.
- the extension can have the mentioned spindle embodiment.
- the spindle nut can also be arranged in the working direction behind the impingement surface of the working piston.
- the spindle nut is preferably firmly connected, optionally also in one piece, to the working piston.
- it can also be rotatably accommodated in the working piston.
- it is not necessary for the spindle itself or possibly the intermediate piston to which it is connected to be rotatable or at least rotate during the course of a work process.
- such a design is advantageous when the coupling extension, ie possibly the spindle, is fastened directly in the hydraulic cylinder and there is no intermediate piston.
- the coupling stop is formed behind the loading surface in the loading direction.
- the intermediate piston can already be biased into a position at a distance from the working piston. This can ensure that the working chamber is also filled with hydraulic fluid in the course of a working process and the associated desired distancing of the working piston from the intermediate piston until, for example, the stop position mentioned is reached. However, it is preferred that no prestressing is required.
- the intermediate piston can have a passage opening provided with a valve, preferably with a valve that can be controlled between an open position and a closed position, in order to enable hydraulic fluid to flow from the working chamber into the antechamber.
- the valve can preferably be opened easily in the direction of the working space, but cannot be opened in the direction of the antechamber, or can only be opened under special conditions.
- the valve in the closed position enables a reduced throughput of hydraulic fluid compared to the open position.
- the valve does not close completely. If a work process comes to an end as mentioned, for example if the object being acted on suddenly breaks through, the effect of the hydraulic fluid in the working chamber, which is under high tension, is nevertheless stopped, since this hydraulic fluid cannot suddenly relax.
- the reduced passage allows a time-delayed and stretched relaxation over time, so that the described stored energy in the working space is reduced without a significant damaging effect on the working tool being associated with this.
- the sudden loss of load has no effect the measures mentioned within a very short period of time, typically within a few milliseconds, while the design described here allows a time extension to a few tens of milliseconds, for example 20 to 40 ms, to be achieved with a significantly lower maximum load on the hydraulic cylinder or of the work tool, up to a maximum load that is no longer noticeable.
- valve can be controlled by a stop on the cylinder base in an open position. If necessary, this can be a second, larger open position. If, after the described end of a work process, hydraulic fluid flows back into a hydraulic tank, for example of the working tool, which can be brought about by controlling a return valve in the open position, with automatic opening of a return valve depending on a certain pressure reached being possible ( compare, for example, WO 99/019947 A1 or US Pat. No. 6,276,186 B1), the working piston and the intermediate piston move back in the direction of the cylinder base. This is usually due to a restoring spring, which, supported on the hydraulic cylinder, acts on the working piston.
- the intermediate piston reaches the bottom of the cylinder after a certain, relatively short distance.
- the resulting control of the valve in the intermediate piston into the (larger) open position can then result in hydraulic fluid flowing back out of the working chamber more quickly.
- the working space is reduced because the working piston moves closer to the intermediate piston.
- Said valve is preferably biased into its closed position, for example by a spring.
- the intermediate piston leaves a gap opening to an inner cylinder surface of the hydraulic cylinder in order to allow hydraulic fluid to flow from the antechamber into the working chamber.
- said valve which is preferably also formed in the intermediate piston in this embodiment, does not allow hydraulic fluid to flow out of the working chamber into the antechamber in its closed position. If the work process ends abruptly, hydraulic fluid can only flow through the gap opening into the antechamber. As a result of the splitting effect, this process is also dampened in the sense mentioned and extended over time, so that the desired gentle reduction of the stored energy can also be advantageously achieved in this way.
- the intermediate piston can also preferably be acted upon independently by a worker with a restraining force that supports hydraulic fluid being able to flow through the intermediate piston into the working space in order to enlarge the working space.
- This retaining force can be achieved, for example, by the already mentioned spring support of the intermediate piston on the working piston. This spring support tends to cause the working piston to increasingly move away from the intermediate piston when a work process is being carried out.
- the retaining force can also, at least in an embodiment in which a gap opening between an inner surface of the hydraulic cylinder and the intermediate piston is not important, consist of a frictional force between the intermediate piston and an inner surface of the hydraulic cylinder, for example caused by a circumferential seal of the intermediate piston, which interacts with said inner surface of the hydraulic piston.
- the retaining force in any case allows a movement of the intermediate piston in the working direction.
- This movement also preferably occurs before there is a rigid coupling between the working piston and the intermediate piston in an embodiment with a shoulder-like extension and a step-like enlargement.
- At least a slight removal of the intermediate piston from the cylinder base in the course of a work process can occur.
- the intermediate piston does not move before the rigid coupling between the working piston and the intermediate piston is established.
- the intermediate piston can be in contact with the cylinder base up to that point and also previously been in contact with the working piston.
- a projection for example rib-like or nub-like, can be formed on the working piston, which ensures that the hydraulic fluid reaches an entire pressure surface of the intermediate piston.
- the working piston is already at a certain distance from the intermediate piston at the start of a working process.
- the working piston is preferably not in direct contact with the intermediate piston, but only by means of the hydraulic fluid already present in the working chamber at the beginning of the working process.
- the hydraulic working tool is accordingly provided with a hydraulic cylinder in one of the above-described embodiments.
- Such a hydraulic working tool can be designed in particular as a cutting tool.
- such a hydraulic working tool has a storage space for hydraulic fluid from which the hydraulic fluid by means of a pump, which is preferably driven by an electric motor, can be pumped into the hydraulic cylinder in order to carry out a work process.
- a controller can also be provided which, for example when there is a drop in pressure that can be interpreted as the end of a cutting process in the case of a cutting tool, moves the aforementioned return valve to an open position so that the hydraulic fluid from the hydraulic cylinder can flow back into the reservoir.
- such a working tool is provided with an accumulator for operating the electric motor.
- the intermediate piston is prevented from moving relative to the working piston in the direction of the cylinder base by a mechanical coupling with the working piston is prevented. This also corresponds to preventing a relative movement of the working piston and the intermediate piston to one another in opposite directions.
- the working piston can also be mechanically coupled to the counter-holder via a spindle part.
- the spindle part can be fastened to the intermediate piston.
- it can also be attached to the hydraulic cylinder itself, preferably to the cylinder base.
- the spindle part can be rotatable.
- a spindle nut is then further preferably provided in the working piston, relative to which the spindle part can be moved axially, in the working direction.
- the spindle part can be fixed and the spin delmutter rotatable, but also the spindle part rotatable and the spindle nut may be provided fixed.
- the rotation of the spindle part can be achieved by rotating the intermediate piston or a corresponding part of the hydraulic cylinder.
- the spindle part can also be rotatably fastened in the intermediate piston or in a corresponding part of the hydraulic cylinder.
- the spindle part can be provided in a stationary manner in the intermediate piston or the hydraulic cylinder.
- the spindle nut is rotatably accommodated in the working piston.
- the spindle nut can initially be held away from its stop surface, which is ultimately effective when the opposing force is removed, by a spring element.
- the stop surface can also be designed to run obliquely in a section obliquely to a longitudinal axis in which the working direction is given.
- FIG. 1 shows a longitudinal section through a hydraulic cylinder with a working head in a first embodiment, before the start of a working process
- FIG. 2 shows a representation according to FIG. 1, at the end of a work process; 3 shows an enlarged illustration of a valve located in an intermediate piston forming a counter-holder, in the position according to FIG. 2;
- FIG. 4 shows a representation according to FIG. 3, in the position according to FIG. 1;
- FIG. 5 shows a representation according to FIG. 1, a second embodiment
- FIG. 7 shows the valve in the intermediate piston of the second embodiment in the position according to FIG. 6;
- FIG. 8 shows the valve in the intermediate piston of the second embodiment in the position according to FIG. 5;
- FIG. 9 shows a representation according to FIG. 1 of a further embodiment, in which the intermediate piston is caught in a spindle nut of the working piston by means of a spindle;
- FIG. 10 shows a representation according to FIG. 9, but with a counter-holder being formed by the hydraulic cylinder;
- FIG. 10a shows a magnified view of the region Xa in FIG. 10.
- Fig. 11 is a schematic representation of a complete hydraulic work tool; 12 is a schematic representation of a return valve.
- a hydraulic working tool 1 is shown and described first with reference to FIG. 11.
- the hydraulic working tool 1 is designed as a hand tool. It preferably has an accumulator 2 , an electric motor 3 , advantageously a gear 4 and a pump 5 . Hydraulic fluid can be pumped from a storage space 7 into a hydraulic cylinder 6 with the pump 5 .
- hydraulic fluid can flow back from the hydraulic cylinder 6 into the reservoir 7 after the end of a work process.
- the return valve 8 is arranged in a hydraulic medium return line, outside and in the working direction R of a working piston 10 in front of the reservoir 7 .
- the hydraulic medium return line can partially coincide with a hydraulic line 22 .
- a grip area surrounding the motor 3 and/or the transmission 4 and/or the pump 5 can be provided.
- an actuating switch 9 can be provided in association with the handle area.
- a first embodiment is shown with reference to FIGS.
- the working piston 10 has an impingement surface 12 . Between the loading surface 12 and an inner surface 13 of the hydraulic cylinder 6 there is a loading space which is divided by the intermediate piston 11 into an antechamber 14 and a working space 15 .
- a working force for carrying out a work process can be transmitted by transmission with a piston rod 16.
- a working head 17, which is connected to the hydraulic cylinder 6, is designed as a cutting tool.
- a first movable cutting edge 18 is connected to the piston rod 16 and is moved against a second fixed cutting edge 19 in the working head 17 in the course of a movement of the working piston 10 .
- An object 20, for example a steel bolt in the exemplary embodiment, can be accommodated between the first and the second cutting edge 18, 19 for cutting.
- the antechamber 14 which is very small in an initial state, as shown in FIG. Via a hydraulic line 22, hydraulic fluid can be drawn from the reservoir by means of the already scribed pump 5, into the vestibule 14 and from there via a valve 23 arranged in the intermediate piston 11 into the working chamber 15. This also results in the working chamber 15 when a work process is carried out, an increasing hydraulic pressure, which leads to a progressive enlargement of the working chamber 15 with movement of the working piston 10 in a working direction R.
- the intermediate piston 11 has a coupling extension 24 which is designed to interact with a coupling stop 25 of the working piston 10 .
- the coupling extension 24 is preferably a radially outwardly directed projection running in a direction transverse to a central axis x of the hydraulic cylinder 6 .
- the radial projection can come to a stop in the working piston 10 with a step-like taper, as which the coupling stop 25 is preferably designed.
- the coupling extension 24 is formed by an area, preferably an end area, of an intermediate piston rod 26 connected to the intermediate piston 11.
- the intermediate piston rod 26 and thus also the coupling extension 24 pass through a through-opening 50 through the impingement surface 12 of the working piston 10.
- the coupling stop 25 is in the embodiment and preferably in a loading direction, which is here with the working direction R, in which the movable cutting edge 18 can move in the direction of the fixed cutting edge 19, is formed behind the loading surface 12.
- the working chamber 15 is filled with hydraulic fluid under very high pressure, at least a pressure of several 100 bar, for example 600 to 800 bar.
- a corresponding back pressure is exerted by the first cutting edge 18 and transmitted through the piston rod 16 by the working piston 10 . If the object 20 suddenly breaks through as a result of the advanced cutting process, for example, the counter-pressure is suddenly eliminated and the energy stored in the hydraulic fluid enclosed in the working chamber 15 between the working piston 10 and the intermediate piston 11, and possibly the working chamber 15 delimiting cylinder wall of the hydraulic cylinder 6 can also, without the precautions taken here, suddenly become free and, in principle, lead to damage.
- the released stored energy leads to an application of force to the surface of the intermediate piston 11 facing the working piston 10 - in the graphic representation of the exemplary embodiment upper - and the loading surface 12 of the working piston 10.
- the coupling extension 24 is in contact with the coupling stop 25 in this position means that the intermediate piston 11 and the working piston 10 cannot move away from one another.
- the valve 23 is preferably and as shown in the drawing, for example by a valve spring 34, biased in its closed position. Even without such a preload, however, the valve 23 is pressed into the closed position when the back pressure suddenly ceases.
- valve 23 is further preferably designed in such a way, compare FIG.
- This passage 27 is very small, so that the effect on the working space 15 at the time hydraulic fluid trapped at the point of severing object 20 equates to a convenient closure. A sudden relaxation is hereby prevented. Nevertheless, this energy stored in the hydraulic fluid can be gently dissipated with a time delay and dampened by the slightly possible backflow of hydraulic fluid through the closed valve 23 .
- valve 23 hits the cylinder base 21 and is thereby moved into the open position according to FIG.
- valve 23 can have an extension 28 projecting in the direction of the cylinder base 21 over a lower surface of the intermediate piston 11 .
- the valve 23 then abuts the cylinder base 21 with the extension 28 and can thereby be moved into the open position according to FIG.
- the valve 23 includes a passage section 29, which is preferably formed like a tube, as in the exemplary embodiment.
- the lead-through section 29 is closed at the top by a closure formation 30 , that is to say towards the working space 15 .
- the passage section 29 has one or more, in the exemplary embodiment preferably two, radial passages 31, through which in the offset state of the Through-line section 29 in the position according to FIG.
- a radial opening 41 of the passage section 29 assigned to the cylinder base 21 acts in the same way in order to enable the hydraulic fluid to flow back into a return line 42 penetrating the cylinder base 21 .
- the closure shoulder 32 is part of a through-opening 33 in the intermediate piston 11, in which the passage section 29 with the closure formation 30 is movably caught.
- the closure formation 30 and/or the closure shoulder 32 leaves the passage 27 already mentioned, which allows a slight flow of hydraulic fluid from the working chamber 15 into the antechamber 14 even when the valve 23 is closed according to FIG.
- the closed state of the valve 23 is preferably achieved by the valve spring 34 acting on the passage section 29 .
- the lead-through section 29 can have a stop shoulder 44 which, as in the exemplary embodiment, can be formed by a snap ring connected to the lead-through section 29 .
- the valve spring 34 can be supported on a stop shoulder 51 formed in the through opening 43 .
- the valve spring 34 is preferably provided to act with such a low force that even when carrying out a work process, when hydraulic fluid is pumped into the antechamber 14 and from there into the working chamber 15, the valve 23 can be moved into its open position and thus The hydraulic fluid can also flow relatively freely through the intermediate piston 11 into the working chamber 15 .
- the intermediate piston 11 is further preferably provided with a circumferential sealing element 35 which acts between the intermediate piston 11 and the inner surface 13 of the hydraulic cylinder 6 .
- this sealing element 35 generates a certain frictional force, which also ensures a retaining force when hydraulic fluid is pumped into the antechamber 14 and from there into the working chamber 15, so that the desired removal of the working piston 10 from the intermediate piston 11 occurs as the pumping continues .
- the sealing element 35 can be an O-ring, for example.
- the intermediate piston 11 is formed without the sealing element 35 in this second embodiment. Rather, a gap opening 36 , which cannot be seen any further in the drawing, is left between the intermediate piston 11 and the inner surface of the hydraulic cylinder 6 .
- the gap opening 36 is preferably set in such a way that, while a work process is being carried out, hydraulic fluid from the reservoir 14 flows around the intermediate piston 11, so to speak, in the work space 15 can flow, but that essentially, as in the first described embodiment, the hydraulic fluid flows through the valve 23 into the work space 15 . After completion of a work process, hydraulic fluid can flow from the work chamber 15 through the gap opening 36 into the antechamber 14 in a greatly restricted manner.
- the setting of the gap opening 36 is also such that when a work process is being carried out, the hydraulic fluid flowing through the gap opening 36 is practically negligible in comparison to the hydraulic fluid flowing through the valve 23 .
- the intermediate piston 11 is loaded with a compression spring 37 which acts between the working piston 10 and the intermediate piston 11 .
- the compression spring 37 is accommodated in a receiving space 38 , which is preferably designed as a blind bore, in the piston rod 16 .
- the compression spring 37 acts here and in the exemplary embodiment on a facing face of the intermediate piston rod 26, preferably in the exemplary embodiment on the coupling extension 24 of the intermediate piston 11.
- valve 23 can also be designed in accordance with the first embodiment in this embodiment.
- FIG. 9 A further embodiment is shown with reference to FIG. 9, in which, however, only the initial state according to FIG. 1 or FIG. 5 is shown. Also with respect to the embodiment of FIG. 9, only the differences are described. Otherwise, the comments on the first two embodiments apply.
- the intermediate piston 11 is formed with a spindle part 39 which interacts with a spindle nut 40 which is formed in the working piston 10 .
- the spindle formation 39 can initially move through the spindle nut 40, if necessary with the intermediate piston 11 also rotating, whereby, as described, at the beginning of a work process, the intermediate piston 11 is also initially removed from the working piston 10 , So an increase in the working space 15 results.
- a configuration according to the second embodiment ie without a sealing element 35, is further preferably provided with regard to the intermediate piston 11.
- This enables and facilitates the rotation of the intermediate piston 11 within the hydraulic cylinder 6, which is possible in a specific embodiment in this regard.
- the valve 23 can nevertheless be designed as described in relation to the first embodiment.
- the valve 23 can also be designed according to the second embodiment here if the gap opening 36 is left between the intermediate piston 11 and the inner surface 13 of the hydraulic cylinder 6, as described in relation to the second embodiment.
- the spindle part 39 accordingly has a spindle thread with a very large pitch, for example in the range of 30 to 60 degrees or more.
- the spindle nut 40 is designed with a corresponding mating thread.
- the spindle nut 40 can be seated in the working piston 10 in a torque-proof manner. It is preferably also designed in one piece with this.
- the spindle part 39 can also sit directly in the cylinder base 21 .
- the intermediate piston 11 can also be omitted entirely.
- the spindle part 39 can be rotatably accommodated in the cylinder base 21 or can also be firmly connected to the cylinder base 21, that is to say non-rotatably connected.
- the spindle part 39 can also be rotatably accommodated in the intermediate piston 11.
- the spindle nut 40 can be movably accommodated in the working piston 10 when the spindle part 39 is held in place, namely rotatably about a Axis of the spindle part during a movement of the spindle part relative to the spindle nut.
- FIG. 1 Another embodiment is shown with reference to FIG. 1
- a spindle part 39 is also provided in this embodiment, which is anchored directly in the cylinder base 21 in this case. As illustrated, it may be bolted into the cylinder base 21.
- the spindle part 39 is operationally non-rotatably anchored in the cylinder base 21.
- the spindle nut 40 is movably, namely rotatably, accommodated in the working piston 10 .
- the spindle nut 40 is held between a front stop 45 in the working direction and a rear stop 46 in the working direction.
- the rear stop 46 is preferably formed by a screw-in part.
- a stop surface 47 of the rear stop 46 and also more preferably a corresponding mating surface 48 of the spindle nut 40 is formed so as to run obliquely in relation to a longitudinal axis of the hydraulic cylinder 6 or in relation to the working direction R in the cross-sectional position of Figure 10. This allows for a favorable self-locking pairing of the surfaces in the event that the surfaces are subjected to force when the counterforce suddenly ceases. The rotation of the spindle nut 40 can thereby be effectively prevented for this moment when the opposing force is no longer present.
- the non-return valve 8 is essentially arranged in an area between the antechamber 14 and the storage chamber 7 and also consists essentially of a valve piston 52 with a pointed conical needle tip 53 arranged centrally on the front side, for the formation of a piston surface 54 which is essential compared to an entire piston surface smaller and defined by the diameter of a bore 55 connected to the vestibule 14 partial piston area (seat valve effective area). The latter is closed by the needle tip 53 in an initial closed position, as shown in FIG.
- valve piston 52 is acted upon at the rear by a pressure spring 56, as a result of which the needle tip 53 is pressed against the bore 55 with a force that also determines a maximum release pressure.
- the aim is for the return valve 8 to be triggered automatically or deliberately.
- the return valve 8 opens at a pressure of, for example, 500 or 600 bar. This maximum pressure is defined by the very small partial piston area of the needle tip 53 projected onto the bore 55 or by the transverse sectional area of the bore 55 and by the contact pressure of the pressure spring 56 on the valve piston 52.
- valve piston 52 If the oil pressure now exceeds the predefined maximum value, the valve piston 52 is moved from its seat sealing the bore 55 against the force of the pressure spring 56, after which a significantly larger piston area, namely the total piston area 54 of the valve piston 52, in effect occurs. Due to the backward displacement of the valve piston 52, an outlet opening 58 arranged in the cylinder 57 accommodating the valve piston 52 is at least partially uncovered for the return flow of the hydraulic medium into the reservoir 7.
- the user of the working tool 1 can open the return valve 8 voluntarily, for example by arranging a hand-operated lever which is accessible from the outside, for example when arranged in the grip area, can act directly or indirectly on the valve piston 52 in such a way that when the lever is actuated accordingly, the valve piston 52 is lifted from its valve seat against the restoring force of the pressure spring 56, so that both the bore 55 and the drain opening 58 are released for the return flow of the hydraulic medium into the storage space 7.
- valve 23 allows hydraulic fluid to flow from the antechamber 14 into the working chamber 15.
- valve 23 in the closed position allows a reduced throughput of hydraulic fluid compared to the open position.
- valve 23 is biased to its closed position.
- An arrangement which is characterized in that the intermediate piston 11 can be acted upon independently by a worker with a restraining force which supports that hydraulic fluid can flow through the intermediate piston 11 into the working space 15 to enlarge the working space 15 .
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Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU2021390167A AU2021390167A1 (en) | 2020-12-03 | 2021-12-02 | Hydraulic work tool with device for impact damping |
CN202180089940.0A CN116745045A (zh) | 2020-12-03 | 2021-12-02 | 带有用于冲击吸收的装置的液压工作工具 |
EP21835623.6A EP4255680A1 (de) | 2020-12-03 | 2021-12-02 | Hydraulisches arbeitswerkzeug mit einrichtung zur stossdämpfung |
US18/265,175 US20240009816A1 (en) | 2020-12-03 | 2021-12-02 | Hydraulic work tool with a device for impact damping |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
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DE102020132185 | 2020-12-03 | ||
DE102020132185.6 | 2020-12-03 | ||
DE102021107120.8 | 2021-03-23 | ||
DE102021107120.8A DE102021107120A1 (de) | 2020-12-03 | 2021-03-23 | Hydraulikzylinder, hydraulisches Arbeitswerkzeug mit einem Arbeitskopf und einem Hydraulikzylinder und Verfahren zur Stoßdämpfung eines in einem Hydraulikzylinder bewegbaren Arbeitskolbens |
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WO2022117753A1 true WO2022117753A1 (de) | 2022-06-09 |
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PCT/EP2021/084030 WO2022117753A1 (de) | 2020-12-03 | 2021-12-02 | Hydraulisches arbeitswerkzeug mit einrichtung zur stossdämpfung |
Country Status (4)
Country | Link |
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US (1) | US20240009816A1 (de) |
EP (1) | EP4255680A1 (de) |
AU (1) | AU2021390167A1 (de) |
WO (1) | WO2022117753A1 (de) |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2863346A (en) | 1956-03-26 | 1958-12-09 | Amp Inc | Hand operated crimping tool |
CH370617A (de) * | 1959-07-15 | 1963-07-15 | Sieber Kilian | Schneideinrichtung |
US3267573A (en) * | 1964-05-26 | 1966-08-23 | Porter Inc H K | Shock absorber |
WO1999019947A1 (de) | 1997-10-15 | 1999-04-22 | Gustav Klauke Gmbh | Hydraulisches pressgerät und verfahren zum betreiben desselben |
WO2003084719A2 (de) | 2002-04-10 | 2003-10-16 | Gustav Klauke Gmbh | Elektrohydraulisches verpressgerät und verfahren zum betreiben desselben |
WO2017080877A1 (de) | 2015-11-10 | 2017-05-18 | Gustav Klauke Gmbh | In einem zylinder geführter hydraulisch beaufschlagter kolben sowie hydraulisches arbeitswerkzeug |
WO2018065513A1 (de) | 2016-10-07 | 2018-04-12 | Gustav Klauke Gmbh | Arbeitswerkzeug |
-
2021
- 2021-12-02 AU AU2021390167A patent/AU2021390167A1/en active Pending
- 2021-12-02 WO PCT/EP2021/084030 patent/WO2022117753A1/de active Application Filing
- 2021-12-02 US US18/265,175 patent/US20240009816A1/en active Pending
- 2021-12-02 EP EP21835623.6A patent/EP4255680A1/de active Pending
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2863346A (en) | 1956-03-26 | 1958-12-09 | Amp Inc | Hand operated crimping tool |
CH370617A (de) * | 1959-07-15 | 1963-07-15 | Sieber Kilian | Schneideinrichtung |
US3267573A (en) * | 1964-05-26 | 1966-08-23 | Porter Inc H K | Shock absorber |
WO1999019947A1 (de) | 1997-10-15 | 1999-04-22 | Gustav Klauke Gmbh | Hydraulisches pressgerät und verfahren zum betreiben desselben |
US6276186B1 (en) | 1997-10-15 | 2001-08-21 | Gustav Klauke Gmbh | Hydraulic pressing device and method for operating the same |
WO2003084719A2 (de) | 2002-04-10 | 2003-10-16 | Gustav Klauke Gmbh | Elektrohydraulisches verpressgerät und verfahren zum betreiben desselben |
US7412868B2 (en) | 2002-04-10 | 2008-08-19 | Gustav Klauke Gmbh | Electrohydraulic pressing device and method for operating same |
WO2017080877A1 (de) | 2015-11-10 | 2017-05-18 | Gustav Klauke Gmbh | In einem zylinder geführter hydraulisch beaufschlagter kolben sowie hydraulisches arbeitswerkzeug |
US10821593B2 (en) | 2015-11-10 | 2020-11-03 | Gustav Klauke Gmbh | Hydraulically actuated piston guided in a cylinder, and hydraulic working tool |
WO2018065513A1 (de) | 2016-10-07 | 2018-04-12 | Gustav Klauke Gmbh | Arbeitswerkzeug |
US20190240826A1 (en) | 2016-10-07 | 2019-08-08 | Gustav Klauke Gmbh | Working tool |
Also Published As
Publication number | Publication date |
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AU2021390167A1 (en) | 2023-06-29 |
EP4255680A1 (de) | 2023-10-11 |
US20240009816A1 (en) | 2024-01-11 |
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