Device for mounting of a turnable implement

A drive of mounting a rotating implement to a crane arm or similar, comprises a rotator located between the crane arm and the unit that at one end is pivot-mounted to the implement for rotating the same relative to the crane arm and slewing around a first pivot axis and at the other end is mounted to the crane arm via a hinged link for slewing around a second pivot axis, a swivel coupling arranged on the rotator for supplying the working chambers of a drive for the rotator and any other consumers included in the unit with a hydraulic medium and that to one end of the swivel coupling is arranged connecting unions, to which hydraulic medium lines leading from the crane arm are attached. For the flexible hydraulic lines between the crane and implement to be both well protected and cannot swing to and fro in an uncontrolled manner during the operational movement of the implement and/or crane arm, the hinged link between the crane arm and the rotator is designed as an open joint defined by two hinged points located at a distance from each other along the joint axis of pivot axis, that the connecting unions are arranged extending parallel to the first pivot axis and facing towards the second pivot axis, whereby the hydraulic medium lines connected to the connecting unions pass between the hinged points situated a distance from each other.

This application is a US national phase of international application PCT/SE02/02117 filed in Swedish on 21 Nov. 2002, which designated the U.S. PCT/SE02/02117 claims priority to SE Application No. 0103935-3 filed 26 Nov. 2001. The entire contents of these applications are incorporated herein by reference.

The present invention concerns structure for suspending a rotating implement, as well as a device for crane-mounted implements.

Crane-mounted rotatable implements such as tree processing units or log grapples are carried by a crane arm for rotating around a first pivot axis comprising the centre or main axis of the implement and at least one other pivot axis relative to the crane arm. This second pivot axis normally comprises one hinged link between the implement and the crane arm. To execute the said pivoting movement a round the first pivot axis, there is a rotator arranged between the implement and the crane arm. Using a swivel coupling in the rotator, a hydraulic medium can be transferred between the crane arm and a hydraulically acting driving means in the rotator and, where appropriate, also between the crane arm and other consumers included in the implement. The driving means in a conventional rotator consumer is served, i.e. supplied with and evacuated of a hydraulic medium, via lines comprising a set of flexible hoses, which, originating from the crane arm in the form of a bunch of hoses hanging outside and at a distance from the implement's hinged links with the crane arm, are attached to the top of the rotator via protruding angled unions. In the pivot pin contained in a rotator are arranged passages running axially, which are in fluidal connection with radial passages running through the wall of a housing surrounding the pivot pin. In known rotators and associated swivel couplings, the housing is the part that is linked to the end of the crane arm, while the pivoted pin in the housing is the part that is linked to the implement. For reasons that are easy to appreciate and mentioned in the foregoing, the connecting unions at the upper end of the rotator to which the pairs of hoses outgoing from the crane arm are connected will extend radially or at an angle from the outside of the swivel coupling's essentially cylinder-shaped housing. The connecting unions at the bottom of the rotator for the pairs of hoses outgoing from the rotator extend in the axial direction of the pivot pin straight down from its flat bottom or end face.

It should also be understood that the hydraulic lines connected to the connecting unions on the upper end of the rotator will for design reasons extend radially from the housing. By means of a certain degree of slackness or excess, the said hydraulic lines connected to the upper end of the rotator will bend away from the hinged link between the implement and the crane arm in so far as they will run clear of and be at such a distance from the said link connections that they will not risk being pinched during the operational movement of the implement. Meanwhile, hydraulic lines or hoses have tended to swing to and fro in an uncontrolled manner during the movement of the implement and sometimes come in contact with tree trunks, wooden stanchions or other objects in the vicinity of the implement and the working range of the crane arm, which can lead to hose failure or other similar damage. Should the occasion arise, not only must the implement undergo costly service with subsequent down-time and reduction in production of the forestry machine as a result but also the hydraulic oil that escapes after, for example, a hose failure will harm the environment.

One object of the present invention is therefore to achieve a means of suspension of an implement of the aforesaid type that does not exhibit the said disadvantages but is so constructed that the flexible hydraulic lines between the crane and the implement are well protected and cannot swing in an uncontrolled manner during the operational movement of the implement and/or crane arm.

A further object is to achieve a rotator that is designed so that the normally occurring radially protruding connecting unions on the top end of the rotator or its housing can be avoided and thereby the hydraulic lines extending between the crane arm and the implement can be positioned more centrally to the link connections between the implement and the crane arm.

A third object of the invention is to achieve a combination of units for crane-mounted rotatable implements whereby all the aforesaid problems have been eliminated.

This can be achieved with the distinctive features and characteristics specified in the following claims.

In the figures, a crane arm is designated1and an implement, which in this case comprises an implement with a means of gripping the tree that can rotate relative to the crane arm is designated2. The implement2is suspended from the free end of the crane arm via a rotator4, one end of which is linked to the crane arm1with an attaching part5and the other end of which is rotatable via a pivot bearing6in the implement frame7for rotating around a first pivot axis A. The rotator4allows the implement to be rotated around the pivot axis A and thereby around its own axis as is illustrated with the arrow loop inFIG. 1. The crane arm also contains a link8at which the attaching part5is supported by the crane arm1via the said link for rotating the implement2around a first and a second relative each other perpendicular pivot axes B and C respectively. Through this mounting, the implement2is allowed to rotate cardanically in two different directions to the said pivot axis A.

Referring toFIGS. 3 and 4, the rotator4carries a swivel pin9that is pivot-mounted in a housing10fastened to the implement's frame7for rotating around the pivot axis A and which swivel pin forms part of a swivel coupling generally designated11for supplying (delivering and evacuating respectively) hydraulic medium to the operating chambers of a hydraulic means of driving12in the rotator4and supplying one or more additional consumers, among them piston-cylinder devices not shown in the figure, used for operating the unit's two means of gripping3.

The rotation and centre axes of pivot bearing6and swivel pin9are coaxial with the first pivot axis A. The delivery and evacuation of hydraulic fluid to the rotator4and the additional consumers of the implement2is done through a first and second pair of flexible lines13that, originating from the crane arm1and extending downwards, are connected to one end of the rotator4. From the other end of the rotator is a pair of lines14(inFIG. 4only indicated with dashed lines) that are connected to the rotator's4means of driving12and other consumers respectively. The said flexible pair of lines13running along the crane arm are connected in a conventional way to a pump and tank respectively on a vehicle (not shown) that is carrying the crane arm in question. The aforesaid components comprising the rotator4and swivel coupling11are arranged to the frame7included in the implement2.

Although this example of a mounting arrangement is illustrated and described for connection to a conventional grapple unit for trees, it should also be understood that the principle for the same nonetheless can be used in combination with any other type of crane-mounted implement such as a felling head with chain saw guide bar intended for a forestry machine or similar.

The unit's two means of gripping3are pivot mounted in a conventional manner with pins15arranged in the frame and each comprises a shank on each side of a line of symmetry through the stand coinciding with the centre axis A.

Referring toFIG. 3, the rotator4comprises an essentially circular upper part16that is fastened with bolts17to an outer gear ring18arranged on the periphery of a slew gear19included in the pivot bearing6. The inner ring designated20for the said slew gear19rests on a plane against the centre axis A at right angles to the top of the frame7and by means of bolts21is fixed to the frame so that the slew bearing's hollow centre concentrically coincides with a hole22in the frame. The means of driving12comprises a hydraulic motor23, which via bolts24is fastened to the frame7in such a way that its geared25drive shaft extends through a second hole26in the frame7and is mesh with the outer gear ring18of the slew bearing in order to turn it and thereby also turn the frame7or implement2in different directions around the first pivot axis A. On the essentially flat top of the frame7is a principally circular housing27covering the outer gear ring that is fastened with bolts28to the said top of the frame. In a similar way, an open-bottomed cover29is arranged on the hydraulic motor23gear wheel25and is clamped between the cover27and the flat top of the frame7.

As illustrated inFIG. 4, the rotator's circular upper part16as well as the free ends of the crane arm1are equipped with a forked part30and31respectively, where each such forked part principally comprises a pair of fork shanks32,32′ at a distance from each other and parallel with the centre axis A, each defining a hinge point. The fork shanks are located relative to each other in such a way that they between them contain a space between the pivot centre of the relatively hinged parts. The link8extending between the crane arm1and the rotator2is similarly equipped at its ends with a forked part33and associated fork shanks34,34′ located a distance from each other, which, as should be illustrated by the figures, is located in the space formed in the forked parts30,31of the crane arm and rotator respectively. The hinged link between each such forked part, located in each other, one in the other, comprises a pair of opposing pins35,35′ that hinge together the respective adjacent fork shanks of the meeting forked parts. The said opposing pair of pins35,35′ are of a length that has been chosen to extend through both on each side of each hinge meeting fork shanks32,32′ and34,34′ respectively without encroaching to any greater degree the space formed between the fork shanks. As the hinge points are separate and positioned at a distance from each other along the pivot axis (B) hinge pin line, a type of open hinge construction is obtained that is both light weight and offers a substantial and broad crane tip with associated broad hinges for secure connection of implements to the crane arm.

The link8is designed as a hollow beam or box and therefore exhibits an axial hole running through it, whereby, as illustrated in the figures, the respective pairs of lines13leading from the crane arm extend through the relative pivot centres B and C respectively of the hinged parts1,2,8, via the inner cavity of the link. Through the resulting open design of the hinged links, the pairs of hydraulic lines13extending between the crane arm1and the unit2can be placed in close proximity to the pivot axis A and in principle so that the pairs of lines cut the axis. Extending through the pivot centres B, C of the relative hinged parts and the link8cavity respectively, the flexible hydraulic lines are both well protected during the movement of the unit and connected to the rotator in close proximity of the pivot axis A and in principle arranged in a circle around the said first pivot axis A. By this arrangement, the hydraulic lines are exerted to only minimal strain from bending and twisting movements also in the case where the implement2is operated between its endmost positions.

In this illustrated embodiment, the crane arm1is of telescopic type comprising two telescopically interposed boom-like parts36,37.FIG. 2shows the telescopic crane arm in contracted and extended position respectively. To prevent the hydraulic lines13running along the outside of the crane arm from swinging to and fro in an uncontrolled manner and possibly thereby also being damaged through entanglement, stretching or friction during the telescopic movement of the crane arm, there is a means of guiding generally designated38arranged on the free end of the crane arm1. The means of guiding38comprises a rigid channel-shaped arm39, one end of which is fastened to the transitional area between the forked part's31join to the crane arm and is located parallel to the outer section of the crane arm1at a distance from its upper side. As illustrated inFIG. 2, the longitudinal concave inside of the rigid arm39facing the crane arm contains the pairs of hydraulic lines13extending between the crane arm1and the unit2, whereby the pairs of lines are arranged against the inside of the arm and are secured to the arm during the relative movements of the boom-like parts. In order to provide a smooth transition of the pair of lines13between the means of guiding38and the hollow interior of the link8during the relative movements of the boom-like parts, the rigid arm, in the area of its joining with the crane arm1, is equipped with a part40that is angled downwards towards the crane arm and via outward extensions on both sides of the downward angled part is rigidly joined to the end of the crane arm.

Referring toFIG. 4, a swivel coupling11is obtained in a conventional manner in that the swivel pin9is pivot-mounted in the housing designated10by means of suitable bearings and seals. For supplying the rotator4means of driving12with hydraulic medium, passages in the form of a set of axially drilled holes41extend through the swivel pin9. These drilled holes open into respective groove-shaped peripheral passages42in the hole wall of the housing and continue via radial passages43out through the wall of the housing10. The swivel pin9exhibits at one end a thicker part44that is mounted in the cavity located in the inner ring20of the centre of the slew bearing19. The upper end of the swivel pin9in the form of the thicker part44is fastened to the rotator's circular upper part16with bolts. The swivel coupling housing10is joined to the frame7via a cross-slotted union46so that the swivel pin and the housing can be moved axially in the slew bearing's19inner ring20for fitting.

Unlike conventional rotators4in which the housing10is normally joined to the crane arm1and is fitted with unions protruding radially towards the pivot axis A for connecting the pairs of lines13coming from the crane arm, and the swivel pin9can be joined to the implement2and is fitted with unions protruding downwards parallel with the pivot axis A for connecting the pair of lines14coming from the rotator, the present rotator4is so designed that it can be mounted in the corresponding way or in the opposite direction. That is to say, that the swivel pin9can be joined to the crane arm1via the rotator's4attaching part5and the housing10can be joined to the implement's frame7. As best illustrated inFIG. 1, this offers the advantage that the connecting unions47located on the end of the swivel pin9and extending parallel with the centre axis are arranged in a circle in the centre of the slew bearing19and face upwards towards a plane that is parallel with the second pivot axis B and to which plane the first pivot axis A, in which the implement2in this case via the link8is suspended from the crane arm, at a normal angle. The connecting unions48for the pairs of lines14coming from the lower end of the rotator are directed radially out from the circular outer of the housing10.

FIG. 5shows the rotator in an alternative embodiment and comprises herein a swivel pin9supported by the attachment part5of the rotator and a housing10that can be joined to the frame of the implement and in which the swivel pin is pivot-mounted through suitable bearings and seals. The attachment part5can be pivot-mounted to the crane arm via a joint for slewing around a pivot axis B. In the area of a cavity or a space50, the swivel pin exhibits a thicker part in which, in a conventional and well-known manner are arranged two spring-loaded flaps or vanes that divide the space into two sub- or working chambers. These parts consequently form the means of driving the rotator12, which here constitutes an integral part of the rotator. Connecting unions47are provided for connecting a pair of lines coming from the crane arm1, and a first pair of axially drilled holes or passages41are provided in the swivel pin9, each one of which opens into a swivel coupling11comprising a set of circular cavities42located at different levels in the housing and into two of which cavities the said drilled holes open. The cavities are connected via radial passages43to the connecting unions48that, protruding radially from the peripheral outer of the housing, are intended for connecting hydraulic medium lines14and thereby supplying other consumers included in the implement such as the illustrated piston-cylinder means used to operate the unit's means of gripping3. Dashed lines illustrate a second pair of axial passages41that also open into two circular cavities42in the swivel coupling. For supplying the rotator4, the said respective circular cavities42are connected to respective working chambers in the housing via respective channels52extending diagonally through the housing. As the flexible and with dashed lines indicated hydraulic lines13leading from the crane arm1to the rotator4can be connected to the rotator axially relative to the first pivot axis A they can be located more centrally in the middle of the hinged links between the implement2and the crane arm1.

FIG. 6shows the present rotator in an embodiment where it not only offers an elegant routing of the lines used to convey a hydraulic medium from the crane arm1to the implement2carried at its end but also allows electric and data signals to be conveyed between the implement and a control system for it that is located in the vehicle carrying the crane arm (not shown in the figures).

FIG. 6shows a longitudinal section through part of the lower end of the rotator4that is facing the implement2. As illustrated inFIG. 6, there is a circular cylindrical cavity generally designated53in the lower end of the swivel pin9centre. In a direction parallel with the centre or pivot axis A extends a drilled hole54that at its top end terminates in an opening fitted with an air filter55. The cavity53is two spaces arranged axially in succession in the form of an outer space55and an inner space56of which the outer space is diametrically somewhat larger then the inner space and contains a swivel and slip-ring unit generally designated57for conveying electrical signals between the implement and the control system. As described earlier, reference number41designates the axial drillings that are used to convey a hydraulic driving medium via a swivel coupling11to a consumer, such as the means of driving12the rotator4. A closer study ofFIG. 6will clearly reveal that a passage58is arranged extending diagonally between one of these axial drillings41and the inner space56.

The swivel and slip-ring unit57comprises a stator59and a rotor60with a number of inter-rotating contact paths of ring-shaped tracks61with slip rings62running in them. The stator59comprises a flange ring upper part63fastened with bolts64to a flat65shoulder made in the transition between the outer and the inner chambers55,56. The rotor60comprises a flange ring lower part66fastened with bolts67to a casing68used to cover the end of the swivel pin9. The said casing68is in turn detachably mounted with bolts69to the rotator4housing10. The casing68has an opening70through which a strand71of a cable from the implement2extends and to which opening the strand is secured with a means of load relief72. The individual conductors73in the said strand71of the cable are in contact with the connecting or contact points74of the rotator part60.

One interesting distinctive feature of the present invention is that one of the axial drillings41, which is normally used to supply a consumer with hydraulic medium via a swivel coupling11, in combination with the diagonally arranged passage58is used as a lead-through for a strand75of a cable from the crane arm1. To be precise, the strand75forms part of the wiring that is in connection with the control system for the implement that is situated in the vehicle carrying the crane arm1. The individual conductors75of the cable are in contact with the connecting or contact points77of the stator59.

In order to both protect the wiring from chafing and to make the cables exhibit characteristics that are essentially comparable to the hydraulic-conveying lines, the hydraulic lines are utilised as through passages for the wiring, whereby such a line can be suitably connected to one of the protruding connecting unions47. Contrary to known technology in which the cables are arranged hanging in bunches so as to go clear of the link connection between the top of the crane and the implement, a uniform and very elegant routing of the hydraulic lines and wiring through the centre of the hinge connection is obtained hereby.

The present invention is not limited to the above description or as illustrated in the drawings but can be changed and modified in a number of different ways within the framework of the idea of invention specified in the following claims.