This application claims the benefit of and priority to German utility model DE 202019101747.3, filed Mar. 27, 2019, which the entire contents are incorporated by reference for all purposes.
The present invention relates to a quick-hitch for coupling a tool to an excavator arm or a similar tool manipulator, comprising two hitch halves that can be latched together and that can be coupled to one another at a first pair of latching parts and can be pivoted together, about the coupled first pair of latching parts, into a coupling position in which a second pair of latching parts of the hitch halves can be latched, wherein energy coupling parts are provided on each of the two hitch halves, which energy coupling parts move together when the hitch halves are pivoted together about the mentioned first pair of latching parts, wherein a coupling carrier is attached to each of the hitch halves, which coupling carrier carries a plurality of energy coupling parts in each case.
Quick couplings for coupling various tools, such as rakers, clamshell buckets or demolition claws, to an excavator arm or similar tool guides such as articulated arm jibs, are often used on construction vehicles such as hydraulic excavators, or articulated grabbers such as wood handling machines or demolition devices, or similar material handling machines, in order to be able to use different tools without long retooling times.
As latching elements, quick couplings of this kind can in particular comprise two mutually spaced latching shafts on one coupling part, while the other coupling part, in particular the coupling part on the excavator arm side, can comprise a preferably hook-shaped coupling receptacle for hooking in a first of the two latching shafts, and a latching receptacle for latching to the second latching shaft. After the first latching shaft has been hooked into the coupling receptacle, the two coupling parts can be pivoted relative to one another, wherein the latching shaft located in the coupling receptacle forms the axis of rotation, such that the second latching shaft is inserted or pivoted into the latching receptacle, where said second latching shaft can then be latched, for example in the manner of an extensible chock, by means of a latching element, such that it is at the same time also no longer possible to move the first latching shaft out of the coupling receptacle. In order to move said latching element, an adjustment actuator that is actuated by external energy is provided, which actuator can for example be designed as a hydraulic cylinder and is typically actuatable by means of hydraulic pressure, from the device.
In this case, said latching shafts on one of the coupling parts can be formed by latching bolts which can extend on the corresponding coupling part, in particular so as to be mutually parallel, wherein it may also be possible, however, for other structural parts of the coupling part, such as protruding lugs, axle journals, engagement stubs in the form of protrusions or recesses, for example in the form of pockets, to be used as the latching part, instead of such bolts, the shape of which parts is matched to the coupling receptacle or the latching receptacle of the other coupling part.
Quick couplings of this kind are also subject to standards with respect to the dimensions and the latching parts, in order to ensure the compatibility of a coupling half used on the excavator arm with various tools on which a coupling half is mounted and which, depending on the tool, may originate from various manufacturers and must be sufficiently compatible with the arm-side coupling half that the two coupling halves can come together and latch. Standardization of this kind is achieved for example in the form of what is known as the S-coupler or the S-standard, which specifies the dimensions and arrangement of the latching elements and receiving jaws and was specified by the Swedish institute Maskinleverantörerna and was last published on 28 May 2010. Said S-coupler comprises, in the manner described above, two mutually parallel transverse bolts as latching parts on one coupling half, while the other coupling half comprises a jaw-like coupling receptacle on one side, and an L-shaped latching receptacle on the other side, on opposing end faces, which receptacles can be locked or closed to form a receptacle which is then also U-shaped or jaw-like, by means of a pair of extensible latching bolts.
Further examples of quick couplings of this kind are known from documents EP 1 852 555 A2, DE 20 2012 007 124 U1 and DE 20 2014 001 328 U1.
In this case, quick-hitches of this kind are often provided with energy couplings, which can for example comprise hydraulic couplings or electrical power couplings, in order to be able to provide energy to the tool to be coupled, by means of an adjustment actuator that is provided on the second hitch half. For example, rotary motors may be provided on the side of the hitch half that is to be coupled, which motors are hydraulically actuated, in order for it to be possible to rotate the tool about an upright axis. Furthermore, adjustment actuators such as hydraulic cylinders or spindle drives comprising electric motors can also be supplied with energy in this manner.
However, in the mentioned type of quick-hitches, the quick-hitch halves of which are pivoted together about the first latching bolt when this is hooked in, it is not particularly easy to bring together the energy couplings. In particular hydraulic couplings react extremely sensitively if they are not brought together in an exactly flush manner, because the hydraulic pins can then cant or jam in the hydraulic bushings into which they are to be inserted, or can damage the coupling parts. The pivot movement of the two hitch halves causes the energy circuit couplings themselves to be moved into one another on a circular path, which inherently also contains a rotary component or a tilting movement component.
In order to prevent these pivot components or the elements coming together on a circular arc, it has already been proposed to decouple the coupling movement from the pivot movement, and to bring the energy couplings together only when the pivot movement has finished. For example, document EP 20 18 456 B1 disclosed a quick-hitch, the hitch halves of which are pivoted together in the manner mentioned. However, the energy couplings are finally coupled together only when the pivot movement has finished, and the second pair of latching parts are latched together. Specifically, the energy couplings are pressed together in a force-locking manner, when the second latching parts pair latches. For this purpose, a latch part that is to be moved has a wedge or sloping surface which, when the latch part is displaced, presses the energy couplings upwards, onto the mating coupling pieces, by means of the wedge action. However, pressing the energy coupling parts against one another in a force-locking manner stresses said parts fairly significantly and can lead to premature wear. In particular, the vibrations arising during rough construction site operation result in micromovements between the energy coupling parts, leading to continuous wear as a result of the force-locking bracing of the energy coupling parts. At the same time, the wedge surface that pushes the energy coupling parts together is itself subject to corresponding wear. As a result, impurities on said wedge surface can lead to the sensitive energy couplings being pushed against one another too firmly.
Furthermore, it has also already been proposed that the problem of the circular path movement should be alleviated by the energy couplings being arranged on a coupling carrier which can tilt relative to the relevant quick-hitch half, specifically about a tilting axis that extends in parallel with the pivot axis of the two quick-hitch halves. In order to actually compensate for the rotary components of the circular path movement upon coupling, the coupling carrier is guided, with respect to the orientation thereof, by separate guide bolts that are inserted into associated guide holes, in order to couple the energy circuit couplings themselves in a manner having an exact linear movement relative to one another. However, exact linear guidance of this kind can be achieved only with a high degree of complexity and allows for no, or only the very smallest, manufacturing tolerances, as a result of which the quick-hitch is expensive to produce. Furthermore, the energy coupling parts react sensitively to wear of said separate guide bolts and holes. When said guide bolts and holes no longer engage with one another in an exactly clearance-free manner, the mentioned canting problem occurs again at the energy coupling parts and can result in damage or even destruction thereof.
The object of the present invention is therefore that of providing an improved quick-hitch of the type mentioned, which overcomes the disadvantages of the prior art and develops said prior art in an advantageous manner. In particular, reliable coupling of the energy coupling parts when the quick-hitch halves are pivoted together is intended to be made possible, which coupling is low-wear even in the case of large manufacturing tolerances, and does not require any complicated mechanics for pressing or separately actuating the energy circuit couplings.
The stated object is achieved according to the invention by a quick-hitch according to claim 1. Preferred embodiments of the invention can be found in the dependent claims.
It is thus proposed for the energy coupling parts to find each other and orientate themselves with one another when the hitch halves are pivoted together, such that the energy coupling parts move into one another in a precisely fitting manner, despite the circular path movement caused by pivoting together the hitch halves. It is furthermore proposed for the energy coupling parts to be designed so as to be self-centering, wherein at least one of the coupling carriers is mounted on the associated hitch half thereof by means of a rubber-elastic carrier bearing so as to be resiliently tiltable in a multiaxial manner, and at least one energy coupling part of each energy coupling part pair that is to be moved together is mounted on the associated coupling carrier by means of a rubber-elastic coupling part bearing so as to be resiliently tilted in a multiaxial manner.
The self-centering of the energy coupling parts with respect to one another makes it possible for the error source of manufacturing tolerances between separate guide bolts/holes and the energy coupling parts to be eliminated, such that the energy coupling parts orient themselves more precisely, relative to one another. If the rotary component of the circular path movement is compensated by means of separate guide bolts and holes, tolerances of position and angle between the guide bolts and holes on the one hand and the energy coupling parts on the other hand result in canting of the energy coupling parts relative to one another. Therefore, the self-alignment of the energy coupling parts relative to one another surprisingly leads to less wear.
In this case, the multi-stage rubber-elastic bearing of the energy coupling parts allows for particularly smooth self-alignment which compensates the rotary components of the circular path movement, wherein the rubber-elastic bearings promote finding of the energy coupling parts and, as a result of the rubber-elastic actuating forces, reduce canting or the tendency to cant. In this case, the rubber-elastic bearing of the coupling carrier allows, in a first stage, for orientation of all the energy coupling parts of one hitch half relative to the energy coupling parts of the other hitch half. Since a plurality of coupling part pairs must find each other, the rubber-elastic bearing of the overall coupling carrier allows for a type of pre-centering. The rubber-elastic bearings, which additionally allow for tilting of individual energy coupling parts relative to the associated coupling carrier, bring about additional fine adjustment, relative to one another, of the two energy coupling parts that find each other in each case, wherein at the same time tolerances of position and/or angle of the energy coupling parts mounted on a common coupling carrier can be compensated. If for example two energy coupling pins are not oriented so as to be exactly mutually parallel, on a coupling plate, even in the case of tilting of the coupling plate this would result in jamming or wear-promotion of the plug-in movement of the two coupling pins in the energy coupling sleeve on the other hitch half. The additional rubber-elastic bearings which allow the energy coupling parts to tilt relative to the coupling carrier can compensate for such shape tolerances or tolerances of position and angle.
In principle, the two coupling carriers can in each case be mounted in a rubber-elastic manner on the two hitch halves, such that each coupling carrier can tilt resiliently in a multiaxial manner relative to the hitch half thereof. In an advantageous development of the invention, however, it is possible for only one of the coupling carriers to be mounted in a rubber-elastic manner on the hitch half thereof, while the coupling carrier on the other hitch half may be rigidly fastened. Unexpectedly, the self-centering of the energy coupling parts relative to one another functions better if only one of the two coupling carriers can tilt resiliently, wherein it may be assumed here that, in the case of rubber-elastic mounting of both coupling carriers, on both sides, simultaneous tilting of both coupling carriers can result in the pivot movement path being over-compensated or the energy coupling parts canting more significantly if both coupling carriers tilt in the same direction.
The rubber-elastic bearings which allow for tilting of the energy coupling parts relative to the coupling carrier can in particular be provided at least on the energy coupling parts which are mounted on the coupling carrier that is itself mounted in a rubber-elastic manner.
In a development of the invention, the mentioned rubber-elastic bearings that allow for tilting of the energy coupling parts relative to the coupling carrier are provided on all the energy coupling parts on both hitch halves. Accordingly, the energy coupling parts on one hitch half can tilt relative to the coupling carrier that is rigidly mounted there. At the same time, the energy coupling parts on the other hitch half can also tilt relative to the coupling carrier that is itself tiltably mounted.
The mentioned energy coupling parts can in particular form coupling plugs that can be plugged into one another. In this case, a coupling plug pair that can be plugged into one another can advantageously comprise a coupling pin and a coupling sleeve, into which said coupling pin can be plugged.
In a development of the invention, the mentioned energy coupling parts can form hydraulic coupling parts in order to be able to convey pressurized fluid away via the two hitch halves. Alternatively or in addition, however, it is also possible for at least one electrical energy coupling part pair to be provided.
In a development of the invention, the self-centering design of the energy coupling parts can comprise a lead-in chamfer on at least one energy coupling part of a pair of energy coupling parts to be coupled. If coupling pins and coupling sleeves that can be plugged into one another in the above-mentioned manner are provided, a lead-in chamber can be formed in particular on the end-face edge of the coupling sleeve.
Alternatively or in addition, however, it would also be possible to provide a lead-in chamber at the end-face end of a coupling pin.
With the exception of the lead-in chamfer, said coupling pins and sleeves can be contoured so as to be in particular at least approximately cylindrical.
In this case, said lead-in chamfer can in principle be contoured differently, for example have cup-shaped curve course. In particular, said lead-in chamfer can have a conical contour. If the relevant energy coupling part is considered in a longitudinal sectional view, the lead-in chamfer can have a straight flank profile.
In an advantageous development of the invention, the lead-in chamfer can be designed having a taper angle of 2 times 20° to 2 times 60° or 2 times 30° to 2 times 50°.
In an advantageous development of the invention, the energy coupling parts are not pushed together in a force-locking manner in the position when coupled together, but instead maintain a certain axial clearance in order not to experience any wear-promoting micromovements as a result of vibrations occurring during operation.
In order to prevent high hydraulic pressure from pushing apart the two energy coupling parts, in the case of hydraulic coupling parts, a securing or latching means that operates in an interlocking manner can be provided, which prevents the rubber-elastic bearings from being pushed apart and/or being overloaded. In particular a latching means that can be latched in an interlocking manner can be provided which, in the normal operating situation when the energy coupling parts are closed, exhibits clearance and allows the energy coupling parts a certain degree of freedom of movement.
In a development of the invention, such a latching means that operates only in an interlocking manner can comprise a displaceable latch which displaceably mounted on a quick-hitch half, for example on the coupling carrier provided there, wherein the displaceability can be provided in a plane perpendicular to the direction of the coupling movement of the energy coupling parts that move into one another.
Said displaceable latch can be latched and/or unlatched by means of an adjustment actuator, for example in the form of a pressure medium cylinder.
In an advantageous development of the invention, the latching means can be designed so as to be self-opening, in particular such that the latching means falls into the lock by itself, irrespective of the current state and/or the current position thereof, and/or is optionally pushed open when the hitch halves are pivoted together and/or when the energy coupling parts are moved together, if the latching part is in the closed position. Such a self-opening design of the latching means prevents the latching means from preventing the energy coupling parts from moving together if the latching means was inadvertently not in the open position when the energy coupling parts are moved together.
Such a self-opening design of the latching means can advantageously be achieved by means of a displaceable latch and/or a detent that is to be latched comprising a lead-in chamfer which exerts a wedge action on the displaceable latch part and pushes the displaceable latch part when said chamfer runs onto the mating surface.
In an advantageous development of the invention, the latching means can comprise a plurality of preferably mushroom-shaped latching pins which are oriented approximately in the direction of the circular arc path and the mushroom-shaped heads of which face forwards when the hitch halves are moved together. The latch part that is complementary to the mushroom-shaped latching pins can be a latching plate in which recesses, preferably in the form of through-holes or open grooves, can be provided, through which the mushroom-shaped latching pins can pass. If the mushroom-shaped heads of the mushroom-shaped latching pins have passed through the recess, the latch part can move transversely to the insertion direction of the latching pins and engage below the mushroom-shaped heads.
The invention will be explained in greater detail in the following, with reference to a preferred embodiment and accompanying drawings. In the drawings:
As shown in
In this case, said quick-hitch 1 can be able to be mounted on said jib arm 5, by means of an arm-side hitch half 2, so as to be pivotable about a horizontal pivot axis that is oriented transversely to the longitudinal axis of the jib arm 5, such that the quick coupling 1, together with the tool 4 attached thereto, can be pivoted relative to the jib arm 5 for example by means of a pressure medium cylinder 36 and an interposed pivot piece 37.
A tool-side hitch half 3 (cf.
As shown in
As shown in
The other hitch half, in particular the tool-side hitch half 3, can comprise two transverse bolts 33 and 34 as latching parts which can be oriented so as to be in parallel with one another and mutually spaced to such an extent that they fit into the openings of the coupling and latching receptacles 6 and 10.
In order to couple the two hitch halves 2 and 3 together, firstly the coupling receptacle 6 is suspended on the transverse bolt 33, wherein a securing element 7 can capture or secure the transverse bolt 33 in the coupling receptacle 6 in order to prevent said bolt from inadvertently slipping out when the two hitch halves 2 and 3 are pivoted together. Said securing element 7 can for example be spring-preloaded and opened by a pressure actuator when the quick-hitch is intended to be decoupled.
If the coupling receptacle 6 is suspended on the transverse bolt 33, as is shown in
As shown in
Said energy coupling parts 12 and 13 can be hydraulic couplings for example. Irrespective thereof, the energy coupling parts 12 and 13 can be designed as plug-in couplings which can be moved into one another and can comprise coupling sleeves and coupling pins that can be inserted therein; cf.
In order to mount the energy coupling parts 12 and 13 on the two hitch halves 2 and 3, a coupling carrier 14 and 15 is provided on each hitch half 2 and 3, which coupling carrier 14 and 15 can be designed in the form of a carrier plate for example, on which the energy coupling parts 12 and 13 can be mounted.
As made clear in
As
The rubber-elastic coupling bearings 18 can advantageously comprise a plurality of annular or plate-shaped rubber bearing parts 19 which are connected between adjacent portions of the energy coupling parts 12 and 13 and/or can be provided between the energy coupling parts 12 and 13 on one side and the coupling carriers 14 and 15 on the other side. Said rubber bearing parts 19 can form rubber hinges which allow for multiaxial tilting of the tips or front portions, to be inserted, of the energy coupling parts.
As
Specifically, the energy coupling parts 12 and 13 center themselves, relative to one another. The self-centering design of the energy coupling parts 12 and 13 comprises lead-in chamfers 22 at the end-face edges of the sleeve-like coupling parts 12, which chamfers may be designed for example in the form of a conical lead-in chamfer or a conical insertion funnel. Alternatively or in addition, a corresponding lead-in chamfer, in particular in the form of a conical chamfering, could also be provided on the end-face edges of the coupling pins 13.
If the energy coupling parts 12 and 13 are moved towards one another and into one another on a circular arc path, by means of pivoting together the hitch halves 2 and 3, said lead-in chamfers 22 bring about self-centering of the energy coupling parts 12 and 13 and compensation of the rotary components of the circular arc path.
In this case, the rubber-elastic bearings of the energy coupling parts 12 and 13 and of the coupling carrier 15 allow for tilting of the energy coupling parts 12 and 13 relative to one another and relative to the particular coupling carrier, as well as, by means of the rubber-elastic carrier bearing 16, also overall tilting of all the energy coupling parts 13 on the tool-side coupler part.
The energy coupling parts 12 and 13 are thus coupled together fully and only by means of pivoting together the two hitch halves 2 and 3, wherein the energy coupling parts are moved together at the same time as the pivoting together takes place and before the process of latching the latch 11 onto the latching receptacle 10 has yet been completed.
In order to prevent the energy coupling parts 12 and 13 from moving apart undesirably, under high hydraulic pressure, an interlocking latching device 23 can be provided which latches the two coupling carriers 14 and 15 in an interlocking manner and prevents said carriers from moving apart. As shown most clearly in
Said transverse latch 26 can be displaced or moved transversely to the insertion direction of the latching pins 24, which can be achieved by means of a suitable actuator, for example in the form of a pressure medium cylinder.
As shown in
Number | Date | Country | Kind |
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202019101747.3 | Mar 2019 | DE | national |
Number | Name | Date | Kind |
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6813851 | Mieger | Nov 2004 | B2 |
20020157287 | Mieger | Oct 2002 | A1 |
20100183417 | Martin | Jul 2010 | A1 |
20150211206 | Otto | Jul 2015 | A1 |
20200291599 | Marchetta | Sep 2020 | A1 |
20220018087 | Iwamoto | Jan 2022 | A1 |
Number | Date | Country |
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102004014824 | Oct 2005 | DE |
102004015471 | Oct 2005 | DE |
102006023420 | Nov 2007 | DE |
202012007124 | Jul 2012 | DE |
202014001328 | May 2015 | DE |
1239087 | Sep 2002 | EP |
1852555 | Nov 2007 | EP |
2018456 | Jan 2009 | EP |
2005093172 | Oct 2005 | WO |
2018074937 | Apr 2018 | WO |
Number | Date | Country | |
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20200308802 A1 | Oct 2020 | US |