FORESTRY WINCH WITH IMPROVED TRANSMISSION GEAR

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 adapted for attachment to a tractor, wherein a power transmission between a driving joint shaft of said tractor and a driven winding drum of said winch could be performed more efficiently by simultaneously reducing loads on each exposed bearing parts, and wherein the transmission gearing should be preferably integrated within said winding drum.

[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. Such winch 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 cable is wound around said drum, which is optionally directed over an upper pulley block towards each load, which shall be towed. The winding drum is embedded within a casing and is mounted on a shaft, on which in addition to said drum also a driving gear of the winding drum is mounted.

[0004] A transmission gear as such is also described in SI 23429 A, which actually concerns a two-step transmission gear with cylindrical gears, wherein a splined shaft is connectable with a cardan joint shaft of a tractor and- is furnished with a gear with a relatively small number of teeth, which is adapted to mesh with the first gear with essentially larger number of teeth, which is mounted on an intermediate shaft. Said intermediate shaft is moreover furnished with a further gear with relatively small number of teeth, which is intended to mesh with said gear on the shaft of the winding drum wherein the lastly mentioned gear is also provided with relatively high number of teeth. Accordingly, the torque i.e. power transmission from the cardan joint shaft onto the winding drum shaft is performed via a two-step reduction gear, which is actually embedded within a casing of the winch, but completely outside of the winding drum, the diameter of which can be consequently relatively small. The winch is basically intended wither for tensioning each towing cable and winding said cable onto the winding drum, or also to release the cable and dispense it from the drum. Each particular position of the tensioning force and consequently also each stresses and stability of the complete appliance depend on position of the towing cable. Each corresponding position of the winding drum within the casing is therefore adjusted to each disposable position of the tensioning force, which then also determines appropriate position of the input shaft, which is connectable to the tractor cardan joint shaft. When considering all these circumstances, in the practice the cardan joint shaft is offset in two planes, which actually undesired, since the dynamic stresses involving undesired impacts and vibrations of particular components are relatively high. Consequently, also the overall efficiency of power transmission from the tractor towards the winding drum of the winch is then correspondingly decreased.

[0005] US 2402756 discloses a winch according to the preamble of claim 1.

[0006] The invention refers to a forestry winch with improved transmission gear for power i.e. torque transmission from the input shaft, which is in detachable manner connectable to a tractor cardan joint shaft, towards the winding drum, which is intended for tensioning or releasing of a towing cable, wherein said transmission gear is adapted to cooperate with alternatively operating clutch and brake, so that by activated clutch the brake is deactivated and the torque can be transmitted from the input shaft onto the winding drum, which is then rotated in one or another direction, or vice versa, and that by activated brake the clutch is deactivated, by which rotation of the winding drum is blocked and at the same time the transmission of torque from the input shaft onto the winding drum is interrupted.

[0007] The invention provides that said transmission gear is formed as a two-step planetary gear consisting of a first planetary assembly and a second planetary assembly, which are embedded within a common casing. In the first planetary gearing, a sun gear is with the possibility of torque transmission mounted on a primary shaft and is by means of the last via said clutch connectable with said input shaft of the transmission gear and is moreover adapted to mesh with corresponding planet gears meshing with inner teeth of an outer ring gear within the casing of the transmission gear. Axle bearings of said planet gears of the first planetary assembly are jointly and with the possibility of torque transmission via a secondary shaft connected with a sun gear of the secondary planet gear, which is capable to mesh with corresponding planet gears, which are capable to mesh with corresponding teeth of an outer ring gear within said casing and axle bearings thereof are jointly and with the possibility of torque transmission connected with the winding drum, by which the casing of the transmission gear is at least partially surrounded, so that said casing of the transmission gear and said winding drum are arranged coaxially with each other and at the same time the winding drum is rotatable relative to said casing.

[0008] Said clutch comprises at least a primary friction disc, with which the input shaft of the transmission gear is connected, and a secondary friction disc, with which said planetary gear is connected. In a preferred embodiment of the invention, the input shaft is connected, in addition to the primary friction disc of the clutch, the secondary friction disc of which is connected with the primary shaft of the planetary gear, also with at least one further transmission gear, via which by means of said input shaft and independently with respect to operation of said clutch, at least one further powered means is driven, in particular a hydraulic media pressurizing pump.

[0009] The invention will be described in more detail on the basis of an embodiment, which is schematically illustrated in Fig. 1.

[0010] A forestry winch according to the invention comprises an improved transmission gearbox 1, which is intended for transmission of torque i.e. power from the input shaft 3 onto a winding drum 3, on which a towing cable 4 is wound.

[0011] Said input shaft 2 is on the one hand detachably, however with the possibility of torque transmission, interconnectable with a cardan joint shaft of each tractor and on the other hand with a clutch 5, namely with a primary friction disc 5' of said clutch 5, while its secondary friction disc 5" is connected with a planetary gear 8, namely with a primary shaft 80' thereof, to which in addition to said secondary friction disc 5" also a brake 7 and a sun gear 811 of the first planetary assembly 81 are connected, which planet gears 812 in the shown embodiment mesh with the inner teeth of the outer ring gear 812 within the casing of said gearbox 1.

[0012] Bearings 812' of axles of said planet gears 812 of the first planetary assembly 81 are jointly connected with a secondary shaft 80", on which a sun gear 821 of the second planet assembly is attached, which in the shown embodiment via planet gears 822 meshes with inner teeth of the outer ring gear 823 within the casing 9 of the transmission gear 1. Bearings 822' of axles of said planet gears 822 of the second planetary assembly 82 are connected with said winding drum 3; with which said casing 9 of the transmission gear 1 is at least partially surrounded. The casing 9, within which said first and second planet assembly 81, 82 are embedded, and said winding drum 3 are arranged coaxially with each other, and at the same the winding drum 3 is rotatable relative to the casing 9.

[0013] The clutch 5 with friction discs 5', 5" and the brake 7 are operating in alternative manner. When the clutch 5 is activated, which means that the primary friction disc 5' and the secondary friction disc 5" are brought in contact with each other in order to establish a required torque transmission via the clutch 5, then the brake 7 is released and allows rotation of the winding drum 3 in one or another direction. As soon as the brake 7 is activated in order to prevent said rotation of the winding drum 3, said friction discs 5', 5" are separated from each other and the clutch 5 is deactivated in order to disable the torque transmission from the input shaft 2 onto a primary shaft 80' and the secondary shaft 80' of the planetary gear 8 of the gearbox 1 and consequently to the winding drum 3, although said shaft 2 continues rotating together with the tractor joint shaft.

[0014] Whenever the forestry winch is controlled by means of a not-shown hydraulic assembly, a hydraulic pump 100 for pressurizing each hydraulic media is foreseen adjacent to the casing 9 and is be driven by means of the input shaft 2 via appropriate transmission assembly 101.

[0015] Since thanks to previously described concept the transmission gear 1 with its casing 9 is embedded within the winding drum 3, the winch according to the invention, when compared with state-of-the art winches, allows essential change of position of the input shaft 2 in each desired position of the towing cable 4 with respect to each position of the towing force, so that the input shaft 2 can be located within the same plane as the cardan joint shaft, namely in the central vertical plane, which means that the cardan joint shaft is located within a single plane instead of being offset in two planes, as known from the prior art, which essentially reduces vibrations and mechanical stresses, to which machine parts are exposed, and at the same time also the efficiency of power transmission can be essentially improved.

[0016] In comparison with known winches, said integration of the planetary gear 8 into the generally pretty wide winding drum 3 might result in certain increasing diameter thereof, which shall however not be understood as a deficiency. On the contrary, bending of the towing cable 4 is less intensive, since the radius of the bending curve is correspondingly enlarged, and besides, enlarging the diameter of the winding drum 3 by winding the same length of the cable leads to reduction of layers of the cable on the surface of the drum, which leads to still further decreasing of loadings, to which the cable is exposed, and moreover also to reduction of variations in diameter of windings, by which also the towing force can be much more uniform. Precisely controlling the operation of the clutch 5 and the brake 7, and herewith accurate operation of the winding drum 3, can be easily achieved by means of cooperation of the clutch 5 and the brake 7 with the first planetary assembly 81 of the transmission gear 8 of the winch. Consequently, the parts are exposed to essentially lower stresses, by which their dimensions and weight can be essentially reduced.

[0017] In particular, the transmission gearbox 1 of the winch according to the invention is an independent construction assembly, which is available within its own casing 9, and can therefore be manufactured separately and independently from any other components in mass production processes, and can therefore be separately assembled, tested, inserted, removed, repaired, or replaced, when appropriate.

Claims

1. Forestry winch with improved transmission gear (1) for power i.e. torque transmission from the input shaft (2), which is in detachable manner connectable to a tractor cardan joint shaft, towards the winding drum (3), which is intended for tensioning or releasing of a towing cable (4), wherein said transmission gear (1) is adapted to cooperate with alternatively operating clutch (5) and brake (7), so that by activated clutch (5) the brake is deactivated and the torque can be transmitted from the input shaft (2) onto the winding drum (3), which is then rotated in one or another direction, or vice versa, and that by activated brake (7) the clutch (5) is deactivated, by which rotation of the winding drum (3) is blocked and at the same time the transmission of torque from the input shaft (2) onto the winding drum (3) is interrupted, characterized in that said transmission gear (1) is formed as a two-step planetary gear (8) consisting of a first planetary assembly (81) and a second planetary assembly (82), which are embedded within a common casing (9), wherein in said first planetary gearing (81) a sun gear (811) is with the possibility of torque transmission mounted on a primary shaft (80') and is by means of the last via said clutch (5) connectable with said input shaft (2) of the transmission gear (1) and is moreover adapted to mesh with corresponding planet gears (812) meshing with inner teeth of an outer ring gear (813) within the casing (9) of the transmission gear (1), and wherein axle bearings (812') of said planet gears (812) of the first planetary assembly (81) are jointly and with the possibility of torque transmission via a secondary shaft (80") connected with a sun gear (821) of the secondary planet gear (82), which is capable to mesh with corresponding planet gears (822), which are capable to mesh with corresponding teeth of an outer ring gear (823) within said casing (9) and axle bearings (822') of which are jointly and with the possibility of torque transmission connected with the winding drum (3), by which the casing (9) of the transmission gear (1) is at least partially surrounded, so that said casing (9) of the transmission gear (1) and said winding drum (3) are arranged coaxially with each other and at the same time the winding drum (3) is rotatable relative to said casing (9).

2. Forestry winch according to Claim 1, characterized in that said clutch (5) comprises at least a primary friction disc (5'), with which the input shaft (2) of the transmission gear (1) is connected, and a secondary friction disc (5"), with which said planetary gear (8) is connected, and in that said input shaft (2) is connected, in addition to the primary friction disc (5') of the clutch (5), the secondary friction disc (5") of which is connected with the primary shat (80') of the planetary gear (8), also with at least one further transmission gear (101), via which by means of said input shaft (2) and independently with respect to operation of said clutch (5), at least one further powered means is driven, in particular a hydraulic media pressurizing pump (100).

Ansprüche

1. Forstseilwinde mit verbessertem Übersetzungsgetriebe (1) zur Energie-, d. h. Drehmomentübertragung von der Antriebswelle (2), die lösbar mit einer Kardangelenkwelle einer Zugmaschine verbindbar ist, auf die Aufwickeltrommel (3), die zum Spannen oder Lösen eines Zugseils (4) vorgesehen ist, wobei das Übersetzungsgetriebe (1) dafür geeignet ist, mit einer Kupplung (5) und einer Bremse (7), die abwechseln arbeiten, zusammenzuwirken, so dass die Bremse durch eine aktivierte Kupplung (5) deaktiviert wird und das Drehmoment von der Antriebswelle (2) auf die Aufwickeltrommel (3) übertragen werden kann, welche dann in die eine oder andere Richtung gedreht wird, oder umgekehrt, und dass die Kopplung (5) durch die aktivierte Bremse (7) deaktiviert wird; wodurch die Drehung der Aufwickeltrommel (3) blockiert wird und gleichzeitig die Übertragung des Drehmoments von der Antriebswelle (2) auf die Aufwickeltrommel (3) unterbrochen wird, dadurch gekennzeichnet, dass das Übersetzungsgetriebe (1) als ein zweistufiges Planetengetriebe (8) ausgebildet ist, welches aus einem ersten Planetenaufbau (81) und einem zweiten Planetenaufbau (82) besteht, die in einem gemeinsamen Gehäuse (9) eingebettet sind, wobei in dem ersten Planetengetriebe (81) ein Sonnenrad (811) mit der Möglichkeit einer Drehmomentübertragung auf einer primären Welle (80') angebracht und durch die wenigstens eine Kupplung (5) mit der Antriebswelle (2) des Übersetzungsgetriebes (1) verbindbar ist und außerdem dazu geeignet ist, mit entsprechenden Planetenrädern (812) ineinander zu greifen, die in Innenzähne eines äußeren Hohlrads (813) innerhalb des Gehäuses (9) des Übersetzungsgetriebes (1) eingreifen, und wobei Achslager (812') der Planetenräder (812) des ersten Planetenaufbaus (81) zusammen und mit der Möglichkeit der Drehmomentübertragung über eine sekundäre Welle (80") mit einem Sonnenrad (821) des sekundären Planetenrades (82) verbunden sind, das in der Lage ist, in entsprechende Planetenräder (822) einzugreifen, die in der Lage sind, in entsprechende Zähne eines äußeren Hohlrads (823) innerhalb des Gehäuses (9) einzugreifen und deren Achslager (822') zusammen und mit der Möglichkeit der Drehmomentübertragung mit der Aufwickeltrommel (3) verbunden sind, von der das Gehäuse (9) des Übersetzungsgetriebes (1) zumindest teilweise umgeben ist, so dass das Gehäuse (9) des Übersetzungsgetriebes (1) und die Aufwickeltrommel (3) koaxial zueinander angeordnet sind und die Aufwickeltrommel (3) gleichzeitig relativ zu dem Gehäuse (9) drehbar ist.

2. Forstseilwinde nach Anspruch 1, dadurch gekennzeichnet, dass die Kupplung (5) wenigstens eine primäre Reibscheibe (5'), mit der die Antriebswelle (2) des Übersetzungsgetriebes (1) verbunden ist, und eine sekundäre Reibscheibe (5") umfasst, mit der das Planetengetriebe (8) verbunden ist, und dass die Antriebswelle (2), außer mit der primären Reibscheibe (5') der Kupplung (5), deren sekundäre Reibscheibe (5') mit der primären Welle (80') des Planetengetriebes (8) verbunden ist, auch mit wenigstens einem weiteren Übersetzungsgetriebe (101) verbunden ist, über welches durch die Antriebswelle (2) und unabhängig vom Betrieb der Kupplung (5) wenigstens eine weitere motorisch betriebene Einrichtung, insbesondere eine hydraulische Medien-Druckpumpe (100), angetrieben wird.

Revendications

1. Treuil forestier avec engrenage de transmission amélioré (1) pour transmission de puissance, c'est-à-dire de couple, depuis l'arbre d'entrée (2), qui peut être relié, de manière détachable, à un arbre à joint de cardan de tracteur, vers le tambour d'enroulement (3), qui est destiné à tendre ou à relâcher un câble de remorquage (4), dans lequel ledit engrenage de transmission (1) est conçu pour coopérer avec un embrayage (5) et un frein (7) fonctionnant en alternance, de sorte que, par l'embrayage (5) activé, le frein est désactivé et le couple peut être transmis de l'arbre d'entrée (2) sur le tambour d'enroulement (3), qui est ensuite mis en rotation dans une direction ou l'autre, ou vice versa, et en ce que, par le frein (7) activé, l'embrayage (5) est désactivé, grâce à quoi la rotation du tambour d'enroulement (3) est bloquée et en même temps la transmission de couple depuis l'arbre d'entrée (2) sur le tambour d'enroulement (3) est interrompue, caractérisé en ce que l'engrenage de transmission (1) a la forme d'un engrenage planétaire (8) à deux étages se composant d'un premier ensemble planétaire (81) et d'un second ensemble planétaire (82), qui sont encastrés dans un boîtier commun (9), dans lequel, dans ledit premier engrenage planétaire (81), un planétaire (811) est monté, avec possibilité de transmission de couple, sur un arbre primaire (80') et peut être relié, à l'aide de ce dernier par le biais dudit embrayage (5), audit arbre d'entrée (2) de l'engrenage de transmission (1) et est en plus conçu pour s'emboîter dans des engrenages planétaires correspondants (812) s'emboîtant dans les dents intérieures d'une couronne dentée extérieure (813) dans le boîtier (9) de l'engrenage de transmission (1), et dans lequel des paliers (812') d'essieu desdits engrenages planétaires (812) du premier ensemble planétaire (81) sont, conjointement et avec possibilité de transmission de couple par l'intermédiaire d'un arbre secondaire (80"), reliés à un planétaire (821) du second engrenage planétaire (82), qui peut s'emboîter dans des engrenages planétaires correspondants (822), qui peuvent s'emboîter dans les dents correspondantes d'une couronne dentée extérieure (823) dans ledit boîtier (9) et dont les paliers (822') d'essieu sont, conjointement et avec possibilité de transmission de couple, reliés au tambour d'enroulement (3), grâce à quoi le boîtier (9) de l'engrenage de transmission (1) est au moins partiellement entouré, de sorte que ledit boîtier (9) de l'engrenage de transmission (1) et ledit boîtier de transmission (3) sont agencés de manière coaxiale l'un avec l'autre et en même temps le tambour d'enroulement (3) peut tourner par rapport audit boîtier (9).

2. Treuil forestier selon la revendication 1, caractérisé en ce que ledit embrayage (5) comprend au moins un disque à friction primaire (5'), auquel l'arbre d'entrée (2) de l'engrenage de transmission (1) est relié, et un disque à friction secondaire (5"), auquel ledit engrenage planétaire (8) est également relié, et en ce que ledit arbre d'entrée (2) est relié, en plus du disque à friction primaire (5') de l'embrayage (5), dont le disque à friction secondaire (5") est relié à l'arbre primaire (80') de l'engrenage planétaire (8), à au moins un autre engrenage de transmission (101), par l'intermédiaire duquel, à l'aide dudit arbre d'entrée (2) et de manière indépendante par rapport au fonctionnement dudit embrayage (5), au moins un autre moyen motorisé est entraîné, en particulier une pompe de mise sous pression (100) d'agent hydraulique.

Drawing