FORESTRY WINCH WITH A HEIGHT-ADJUSTABLE PULLEY

Description

[0001] In the field of transporting, the invention refers to hoisting, lifting or hauling appliances, in particular to winches, namely to construction details thereof.

[0002] The purpose of the invention is to create a forestry winch, which could be attached to a tractor, and in which a towing rope, depending on each position of acting each tensioning forces, could be optionally placed over a rope pulley of a higher positioned pulley block, or over a rope pulley of a lower positioned pulley block, wherein said lower pulley block shall be height adjustable with a constant velocity, and should moreover act on the towing rope with a constant force.

[0003] A forestry winch as such is described e.g. in SI 9600339 A2. Such winch comprises a casing, which is on the one hand furnished with beams for establishing connection with a three-point mechanism of an usual tractor, as well as with an end portion of a shaft suitable for connection with a joint shaft of a tractor. The opposite side of said housing is furnished with a deflecting surface, a so-called board, which essentially forms a part of casing of a driving and towing unit in such winch, which moreover comprises a winding drum with a brake and a clutch, as well as a reduction gearbox, via which said shaft is connected to said end portion of the shaft for connection with said joint shaft of each tractor. A towing rope is wound around said drum, which is optionally directed over an upper pulley block or over a lower pulley block towards each load, which shall be towed. Said pulley blocks are each per se attached to said winch casing in such manner, than each of them is independently pivotal around its vertical axis at a predetermined angle, by which the pulley can be adjusted to each particular direction of the towing rope relative to each particular position of the tractor furnished with such winch. When smaller loads are towed, said rope can be directed over the upper pulley block, while by towing heavier loads the rope must be released and placed over the lower pulley block. By such measure, the position of tension forces is adjusted, namely the distance thereof apart from the ground, by which the stability of the tractor is assured in the case of applying essential towing forces, since on the contrary the tractor could start tilting or overturning.

[0004] The lower pulley block of a forestry winch is described in SI 23476 A. However both SI 9600339 A2 and SI 23476 A disclose a lower pulley block, which is not height-adjustable. The position of each rope pulley in such pulley block can be changed by pivoting around the vertical axis, by which the position of the pulley is adjusted to each direction of the towing rope. In this, SI 23476 A has proposed that the rope pulley in such lower pulley block is by means of a magnet held in its end position, by which undesired pivoting of the pulley during transporting or storage is prevented.

[0005] During a practical exploitation, such winch is used in situ, wherein each configuration of terrain can essentially vary. The height of the lower pulley block is determined in advance, and prior to towing heavier loads, the rope has to be redirected from the pulley of the upper pulley block to the pulley of the lower pulley block, which with respect to configuration of the ground located too low. In such situation there is a need on introduction of a height-adjustable lower pulley block, which should be displaced at least in such extent that the tensioned rope used for towing the load would not be in contact with the ground. The applicant is aware of attempts, according to which the lower pulley block was embedded within a guide in order to enable displacements of said lower pulley block in the vertical direction, by which such displacements were established by means of a multi-step i.e. telescopic hydraulic cylinder. Such approach generally enables achieving of sufficient height-displacement of the lower pulley block, wherein however the velocity of such displacing is not constant, and the force for supporting the pulley, over which the towing rope is directed, is decreased proportionally to the height. In a telescopic hydraulic cylinder, the surface exposed to the pressure is step-like changing. This means that by supplying each hydraulic media into a cylinder, the velocity of displacing the piston rod and the force produced by piston rod are step-like changing. The efficiency of generating a supporting force is therefore in contradiction with actual needs, in accordance with which the towing rope shall be redirected over the lower pulley block when the heavier loads are towed, which should jeopardize the stability of each tractor. Consequently, such redirecting of the towing rope from the upper pulley block to the lower pulley block may be helpful in the sense of maintaining the stability of the tractor despite to applying essentially higher towing force, while at the same time the disposable force on the lower pulley block is essentially reduced. A winch according to the prior art is disclosed in document US 4,238,116.

[0006] The invention refers to a forestry winch, which is in particular adapted for attachment to a three-point mechanism of a tractor and comprising a casing, within which a winding drum is embedded, which is driven by means of a joint shaft of said tractor via appropriate clutch and appropriate transmission gear and is adapted for tensioning or releasing of a towing rope, wherein at least an upper pulley block and at least one lower pulley block are available on the external surface of said winch casing, by which said lower pulley block is arranged at appropriate distance above the ground, and said towing rope can be directed either via the upper pulley block, or alternatively via the lower pulley block, and wherein the lower pulley block, consisting at least of a supporting beam, a casing which is allowed to pivot relative to said beam at certain angle around an axle, as well as of a rope pulley which is embedded within said casing with the possibility of freely rotating, is embedded within each belonging guide on the winch casing and vertically displaceable along said guide.

[0007] According to the invention, said lower pulley block is vertically displaceable by means of a flexible towing member, which is by means of its first end portion attached to said supporting beam and by means of its second end portion to a fixed fastening point, wherein a resting member, which is attached on a displaceable part of a working cylinder, is pressed towards said flexible towing member in the area between said supporting beam and said fixed fastening point, wherein said cylinder consists of said displaceable part as well as of a stationary part, which is connected to the winch casing.

[0008] A piston rod together with a belonging piston can e.g. be used as the displaceable part of the working cylinder, while on the contrary an alternative embodiment of the invention provides that said piston rod together with a belonging piston can also be used as the stationary part of the working cylinder.

[0009] One of embodiments of the invention further provides that between the supporting beam of the lower pulley block and the resting member at least one redirecting member is available, via which a flexible towing member is directed. The invention however further provides that between the fixed fastening point of the flexible towing member on the winch casing and the resting member at least one redirecting member can be available, via which a flexible towing member is directed. In general, between the fixed fastening point and the supporting beam (of the lower pulley block at least one redirecting member is available, via which a flexible towing member is directed.

[0010] Said flexible towing member is selected from the group consisting of ropes, belts, chains or combinations thereof.

[0011] Said resting member is pivotally, in particular freely rotationally, connected with the displaceable part of the cylinder.

[0012] Each desired resting member is adapted to each disposable flexible towing member and is selected from the group consisting of rope pulleys, belt pulleys and chain wheels.

[0013] Each desired redirecting member is adapted to each disposable flexible towing member and is selected from the group consisting of rope pulleys, belt pulleys and chain wheels.

[0014] The invention will be described in more detail on the basis of an embodiment, which is schematically illustrated in Fig. 1.

[0015] Similarly like the previously mentioned state of the art winches, also the winch according to the invention comprises a lower pulley block 1, which is by means of a not shown guide, which is attached to each disposable casing of the winch and is intended for guiding of a towing rope 2, optionally together with each particular load.

[0016] Said lower pulley block 1 consists of a supporting beam 11, which is adapted to cooperate with said guide on the winch casing and is furnished with two ears 12', 12", which are located above each other and through which a vertical axle 13 is extending, which is integrated within the casing 14 of the lower pulley block 1, where also a pulley 15 is rotatable embedded, over which said towing rope 2 is directed. Thanks to said ears 12', 12 and to said axle 13, the lower pulley block 1 can be pivoted at a desired angle around the vertical geometric axis, which corresponds to the longitudinal central axis of said axle 13.

[0017] Said supporting beam 11 of the lower pulley block 1 is vertically displaceable along said not-shown guide by means of a flexible towing member 3, which is selected from the group consisting of ropes, belts and chains, or various combinations thereof, and which is guided via at least one redirecting member 4, 4', which is, depending on each used towing member 3, selected from the group consisting of rope pulleys, belt pulleys and chain wheels.

[0018] Said flexible towing member 3 is by means of its one end portion 3' attached to said supporting beam 11 of the lower pulley block 1, and by means of its other end portion 3" to a fixed fastening point 5, which is preferably available on the winch casing.

[0019] A resting member 7 is arranged between said at least one supporting beam 11 of the lower pulley block 1 and said fixed fastening point 5 of the flexible towing member 3, and is rest on said flexible towing member 3 for the purposes of cooperating therewith in the sense of tensioning or releasing thereof. To this aim, depending on each used flexible towing member 3, a rope pulley or a belt pulley or a chain wheel or at least a circumferential section of one of these elements can be used for the purposes of establishing such resting member 7.

[0020] Said resting member 7 is attached to each displaceable part 81 of a working cylinder 8, which is in the shown embodiment available as a hydraulic cylinder, while the stationary part 82 of said cylinder 8 is optionally together with said fixed fastening point 5 or independently there-from, attached to the winch casing. In a preferred embodiment of the invention, said resting member 7 is rotationally attached onto said displaceable part 81 of the cylinder 8.

[0021] One skilled in the art shall understand that an alternative embodiment of the invention can also provide, that a piston rod of a cylinder 8 is used as a stationary part 82, which is attached to each disposable winch casing, wherein in such case said resting member 7 is attached to the cylinder as such. In such case, said displaceable part 81 is a cylinder, while said stationary part 82 is a piston rod together with a belonging piston.

[0022] When said supporting beam 11 is embedded in each corresponding guide and is located in each desired position, a flexible towing member 3 is attached thereto by means of its first end portion 3', while its second end portion 3" is attached to said fixed fastening point 5. The resting member 7 is pressed towards said flexible towing member 3 extending between said supporting beam 11 of the lower pulley block 1 and the fixed fastening point 5, preferably via at least one further redirecting member 4, 4'. When each required pressure P is established within said cylinder 8, the displaceable part 81 of the cylinder 8 is displaced together with said resting member 7 in one or another direction, by which said flexible towing member 3 is either tensioned or released, depending on which then the lower pulley block 1 is displaced along the belonging guide, by which each desired vertical position of said lower pulley block 1 can be adjusted. Said working cylinder 8 is a simple single-stroke i.e. non-telescopic cylinder, so that displacing of said resting member 7 and correspondingly tensioning or releasing of the flexible lowing member 3 is performed with a constant velocity and uniform transmission ratio, which means that also the tension force within the flexible towing member 3 is constant regardless to each position of the lower pulley block 1.

Claims

1. A forestry winch, which is in particular adapted for attachment to a three-point mechanism of a tractor and comprising a casing, within which a winding drum is embedded, which is driven by means of a joint shaft of said tractor via appropriate clutch and appropriate transmission gear and is adapted for tensioning or releasing of a towing rope (2), wherein at least an upper pulley and at least one lower pulley block (1) are available on the external surface of said winch casing, by which said lower pulley block (1) is arranged at appropriate distance above the ground, and said towing rope (2) can be directed either via the upper pulley, or alternatively via a pulley (15) of the lower pulley block (1), and wherein the lower pulley block (1), consisting at least of a supporting beam (11), a casing (14) which is allowed to pivot relative to said beam (11) at certain angle around an axle (13), as well as of a pulley (15) which is freely rotatable embedded within said casing (14), is adapted to cooperate with guides on the winch casing and characterised in that the lower pulley block (1) is vertically displaceable along said guide, and that said lower pulley block (1) is vertically displaceable by means of a flexible towing member (3), which is by means of its first end portion (3') attached to said supporting beam (11) and by means of its second end portion (3") to a fixed fastening point (5), wherein a resting member (7), which is attached on a displaceable part (81) of a working cylinder (8), is pressed towards said flexible towing member (3) in the area between said supporting beam (11) and said fixed fastening point (5), wherein said cylinder (8) consists of said displaceable part (81) as well as of a stationary part (82) which is connected to the winch casing.

2. Winch according to Claim 1, characterized in that said displaceable part (81) of the working cylinder (8) is a piston rod with each belonging piston.

3. Winch according to Claim 1, characterized in that said stationary part (82) of the working cylinder (8) is a piston rod together with each belonging piston.

4. Winch according to anyone of Claims 1 - 3, characterized in that between the supporting beam (11) of the lower pulley block (1) and the resting member (7) at least one redirecting member (4, 4') is available, via which a flexible towing member (3) is directed.

5. Winch according to anyone of Claims 1 - 3, characterized in that between the fixed fastening point (5) of the flexible towing member (3) on the winch casing and the resting member (7) at least one redirecting member (4, 4') is available, via which a flexible towing member (3) is directed.

6. Winch according to anyone of Claims 1 - 3, characterized in that between the fixed fastening point (5) and the supporting beam (11) of the lower pulley block (1) at least one redirecting member (4, 4') is available, via which a flexible towing member (3) is directed.

7. Winch according to anyone of Claims 1 - 6, characterized in that said flexible towing member (3) is selected from the group consisting of ropes, belts, chains or combinations thereof.

8. Winch according to anyone of Claims 1 - 7, characterized in that said resting member (7) is pivotally connected with the displaceable part (81) of the cylinder (8).

9. Winch according to anyone of Claims 1 - 8, characterized in that said resting member (7) is freely rotationally connected with the displaceable part (81) of the cylinder (8).

10. Winch according to anyone of Claims 1 - 9, characterized in that each desired resting member (7) is adapted to each disposable flexible towing member (3) and is selected from the group consisting of rope pulleys, belt pulleys and chain wheels.

11. Winch according to anyone of Claims 1 - 9, characterized in that each desired redirecting member (4, 4') is adapted to each disposable flexible towing member (3) and is selected from the group consisting of rope pulleys, belt pulleys and chain wheels.

Ansprüche

1. Forstseilwinde, die insbesondere zur Anbringung an einem Dreipunktmechanismus einer Zugmaschine geeignet ist und ein Gehäuse umfasst, in welchem eine Aufwickeltrommel eingebettet ist, die mittels einer Gelenkwelle der Zugmaschine über eine geeignete Kupplung und ein geeignetes Übersetzungsgetriebe angetrieben wird und dazu geeignet ist, ein Schleppkabel (2) zu spannen oder zu lösen, wobei wenigstens eine obere Riemenscheibe und wenigstens ein unterer Flaschenzug (1) auf der Außenfläche des Seüwindengehäuses vorhanden sind, wodurch der untere Flaschenzug (1) in einem geeigneten Abstand oberhalb des Bodens angeordnet ist und das Schleppkabel (2) entweder über die obere Riemenscheibe oder alternativ über eine Riemenscheibe (15) des unteren Flaschenzugs (1) gelenkt werden kann, und wobei der untere Flaschenzug (1), der wenigstens aus einem Stützbalken (11), einem Gehäuse (14), welches relativ zu dem Balken (11) um einen bestimmten Winkel um eine Achse (13) schwenkbar ist, sowie aus einer Riemenscheibe (15) besteht, die frei drehbar in dem Gehäuse (14) eingebettet ist, dazu geeignet ist, mit Führungen auf dem Seilwindengehäuse zusammenzuwirken, und dadurch gekennzeichnet, dass der untere Flaschenzug (1) vertical entlang der Führung verschiebbar ist und dass der untere Flaschenzug (1) mittels eines flexiblen Schleppelements (3), welches mittels seines ersten Endabschnitts (3') an dem Stützbalken (11) und mittels seines zweiten Endabschnitts (3") an einem festen Befestigungspunkt (5) angebracht ist, vertikal verschiebbar ist, wobei ein Ruheelement (7), welches auf einem verschiebbaren Teil (81) eines Arbeitszylinders (8) angebracht ist, im Bereich zwischen dem Stützbalken (11) und dem festen Befestigungspunkt (5) zum flexiblen Schleppelement (3) hin gedrückt wird, wobei der Zylinder (8) aus dem verschiebbaren Teil (81) sowie aus einem feststehenden Teil (82) besteht, welches mit dem Seilwindengehäuse verbunden ist.

2. Seilwinde nach Anspruch 1, dadurch gekennzeichnet, dass der verschiebbare Teil (81) des Arbeitszylinders (8) eine Kolbenstange mit jeweils zugehörigem Kolben ist.

3. Seilwinde nach Anspruch 1, dadurch gekennzeichnet, dass der feststehende Teil (82) des Arbeitszylinders (8) eine Kolbenstange zusammen mit jeweils zugehörigem Kolben ist.

4. Seilwinde nach einem der Ansprüche 1 - 3, dadurch gekennzeichnet, dass zwischen dem Stützbalken (11) des unteren Flaschenzugs (1) und dem Ruheelement (7) wenigstens ein Umlenkelement (4, 4') vorhanden ist, über welches ein flexibles Schleppelement (3) gelenkt wird.

5. Seilwinde nach einem der Ansprüche 1 - 3, dadurch gekennzeichnet, dass zwischen dem festen Befestigungspunkt (5) des flexiblen Schleppelements (3) auf dem Seilwindengehäuse und dem Ruheelement (7) wenigstens ein Umlenkelement (4, 4') vorhanden ist, über welches ein flexibles Schleppelement (3) gelenkt wird.

6. Seilwinde nach einem der Ansprüche 1 - 3, dadurch gekennzeichnet, dass zwischen dem festen Befestigungspunkt (5) und dem Stützbalken (11) des unteren Flaschenzugs (1) wenigstens ein Umlenkelement (4, 4') vorhanden ist, über welches ein flexibles Schleppelement (3) gelenkt wird.

7. Seilwinde nach einem der Ansprüche 1 - 6, dadurch gekennzeichnet, dass das flexible Schleppelement (3) aus der aus Seilen, Gurten, Ketten oder Kombinationen davon bestehenden Gruppe ausgewählt ist.

8. Seilwinde nach einem der Ansprüche 1 - 7, dadurch gekennzeichnet, dass das Ruheelement (7) schwenkbar mit dem verschiebbaren Teil (81) des Zylinders (8) verbunden ist.

9. Seilwinde nach einem der Ansprüche 1 - 8, dadurch gekennzeichnet, dass das Ruheelement (7) frei drehbar mit dem verschiebbaren Teil (81) des Zylinders (8) verbunden ist.

10. Seilwinde nach einem der Ansprüche 1 - 9, dadurch gekennzeichnet, dass jedes gewünschte Ruheelement (7) für jedes verfügbare flexible Schleppelement (3) geeignet ist und aus der aus Seilrollen, Gurtrollen und Kettenrädern bestehenden Gruppe ausgewählt ist.

11. Seilwinde nach einem der Ansprüche 1 - 9, dadurch gekennzeichnet, dass jedes gewünschte Umlenkelement (4, 4') für jedes verfügbare flexible Schleppelement (3) geeignet ist und aus der aus Seilrollen, Gurtrollen und Kettenrädern bestehenden Gruppe ausgewählt ist.

Revendications

1. Treuil forestier, qui est en particulier conçu pour être fixé à un mécanisme à trois points d'un tracteur et comprenant un boîtier, dans lequel est encastré un tambour d'enroulement, qui est entraîné à l'aide d'un arbre articulé dudit tracteur par l'intermédiaire d'un embrayage approprié et d'un engrenage de transmission approprié et est conçu pour tendre ou relâcher un câble de remorquage (2), dans lequel au moins une poulie supérieure et au moins une moufle inférieure (1) sont disponibles sur la surface externe dudit boîtier de treuil, grâce auquel ladite moufle inférieure (1) est agencée à une distance appropriée au-dessus du sol, et ledit câble de remorquage (2) peut être orienté par le biais de la poulie supérieure, ou en variante par le biais d'une poulie (15) de la moufle inférieure (1), et dans lequel la mouffe inférieure (1), se composant d'au moins une poutre de support (11), d'un boîtier (14) qui peut pivoter par rapport à ladite poutre (11) selon un certain angle autour d'un axe (13), ainsi que d'une poulie (15) qui est encastrée de manière à pouvoir tourner librement dans ledit boîtier (14), est conçue pour coopérer avec des guides situés sur le boîtier de treuil et caractérisé en ce que la moufle inférieure (1) peut être déplacée verticalement le long dudit guide, et en ce que ladite moufle inférieure (1) peut être déplacée verticalement à l'aide d'un élément de remorquage flexible (3), qui, à l'aide de sa première partie d'extrémité (3'), est fixé à ladite poutre de support (11) et à l'aide de sa seconde partie d'extrémité (3") est fixé à un point de fixation fixe (5), dans lequel un élément d'appui (7), qui est fixé sur une pièce déplaçable (81) d'un cylindre de travail (8), est pressé vers ledit élément de remorquage flexible (3) dans la région située entre ladite poutre de support (11) et ledit point de fixation fixe (5), dans lequel ledit cylindre (8) se compose de ladite pièce déplaçable (81) ainsi que d'une pièce fixe (82) qui est reliée au boîtier de treuil.

2. Treuil forestier selon la revendication 1, caractérisé en ce que ladite pièce déplaçable (81) du cylindre de travail (8) est une tige de piston avec chaque piston associé.

3. Treuil forestier selon la revendication 1, caractérisé en ce que ladite pièce fixe (82) du cylindre de travail (8) est une tige de piston avec chaque piston associé.

4. Treuil forestier selon l'une quelconque des revendications 1 à 3, caractérisé en ce que, entre la poutre de support (11) de la moufle inférieure (1) et l'élément d'appui (7), se trouve au moins un élément de réorientation (4, 4'), par l'intermédiaire duquel est orienté un élément de remorquage flexible (3).

5. Treuil forestier selon l'une quelconque des revendications 1 à 3, caractérisé en ce que, entre le point de fixation fixe (5) de l'élément de remorquage flexible (3) sur le boîtier de Treuil et l'élément d'appui (7), se trouve au moins un élément de réorientation (4, 4'), par l'intermédiaire duquel est orienté un élément de remorquage flexible (3).

6. Treuil forestier selon l'une quelconque des revendications 1 à 3, caractérisé en ce que, entre le point de fixation fixe (5) et la poutre de support (11) de la moufle inférieure (1), se trouve au moins un élément de réorientation (4, 4'), par l'intermédiaire duquel est orienté un élément de remorquage flexible (3).

7. Treuil forestier selon l'une quelconque des revendications 1 à 6, caractérisé en ce que ledit élément de remorquage flexible (3) est choisi dans le groupe constitué de câbles, de courroies, de chaînes ou de combinaisons de ceux-ci.

8. Treuil forestier selon l'une quelconque des revendications 1 à 7, caractérisé en ce que ledit élément d'appui (7) est relié pivotant à la pièce déplaçable (81) du cylindre (8).

9. Treuil forestier selon l'une quelconque des revendications 1 à 8, caractérisé en ce que ledit élément d'appui (7) est relié, de manière à pouvoir tourner librement, à la pièce déplaçable (81) du cylindre (8).

10. Treuil forestier selon l'une quelconque des revendications 1 à 9, caractérisé en ce que chaque élément d'appui (7) souhaité est adapté à chaque élément de remorquage flexible (3) disponible et est choisi dans le groupe constitué de poulies à câble, de poulies à courroie et de roues à chaîne.

11. Treuil forestier selon l'une quelconque des revendications 1 à 9, caractérisé en ce que chaque élément de réorientation (4, 4') souhaité est adapté à chaque élément de remorquage flexible (3) disponible et est choisi dans le groupe constitué de poulies à câble, de poulies à courroie et de roues à chaîne.

Drawing