Gripping device with closing drive through geared force multiplication

Abstract

Gripping device (10) for a rope gripper (12), comprising a) a rope suspension (22) to which the gripping device (10) is attached, b) an upper cross member (24) of the gripping device (10), on which locking rods (28) are articulated, c) a lower cross member (34) of the gripping device (10), on which gripping shells (36) are arranged in an articulated manner, wherein at least one locking rod (28) is connected in an articulated manner to a gripping shell (36), d) an actuating mechanism (48) which controls the distance between the lower cross member (34) and the upper cross member (24) for opening or closing the gripping shells (36), e) the actuating mechanism (48) has a mounting platform (50) on which a drive (52) with a reduction gear (54, 56) is arranged, which drives an adjusting device (58) for opening and closing the gripping shells (36), wherein the adjusting device (58) is connected to the upper cross member (24) and the lower cross member (34) in an adjusting manner, characterized in that f) the drive (52) has a rotatable drive cable drum (60) with a drive cable (20a, 20b), wherein the drive cable (20a, 20b) is driven by the cable gripper (12) and drives the drive drum (60), wherein g) the adjusting device (58) has a cable pulley (62, 64) with a winding or unwinding adjusting cable (66, 68) for controlling the distance between the cross members (24, 34), wherein the cable pulley (62, 64) is rotatably mounted in the mounting platform (50) and is coupled to the reduction gear (54, 56).

Description

Technical FieldThe invention relates to a gripping device for a cable gripper, comprising a) a cable suspension to which the gripping device is fastened, b) an upper cross-member of the gripping device, on which closing rods are arranged in an articulated manner, c) a lower cross-member of the gripping device, on which gripping shells are arranged in an articulated manner, wherein in each case at least one closing rod is connected in an articulated manner to a gripping shell, d) an actuating mechanism which controls the distance between the lower and upper cross-members for opening or closing the gripping shells, e) the actuating mechanism has a mounting platform on which a drive with a reduction gear is arranged, which drive drives an adjusting device for opening and closing the gripping shells, wherein the adjusting device is connected in an adjustable manner to the upper and the lower cross-member.DESCRIPTION OF THE INVENTIONSuch cable grippers, such as excavators, cranes and comparable machines, are used in particular for transferring or reloading goods, such as e.g. garbage, scrap, bulk material or the like, by lifting. For this purpose, the machines have spoons, bucket grippers, hooks, karabiners or other gripping means. They are therefore easily used for loading or unloading, for example, ships, goods trains or trucks.Excavators with rigid booms can only reach a fixed depth at any time, since the length of the booms is largely fixed by the rigid boom components which are moved electrically or with hydraulic cylinders. Cranes have the advantage over these excavators with rigid booms that they can pick up or unload the material with their ropes almost as low or as high as desired.So-called excavators are also known as cable grippers. These can grip the depth relatively far with their grippers or shell grippers. The depth in such machines is limited only by the cable length. The grippers are actuated by suitably arranged pulley trains and deflection rollers. Cable-winding rollers are driven for this purpose by electric drives and / or by internal combustion engines. These cable winding rollers wind up or down the cable or the cables of the cable grippers as required.The gripping shells are actuated by ropes. By lengthening or shortening the cables, the gripping shells are opened or closed.Prior ArtDE 1731 261 U describes a hydraulically actuatable multishell gripper which has resilient stops on the gripping shells, which, when the gripper is opened, support against counterstops on the lower case and limit the opening movement.DE 27 18 434 C2 discloses a gripper articulated on the boom of a working machine. The gripper comprises at least two gripping shells which can be actuated by a hydraulic cylinder. The gripping shells are articulated on a lower cross-member. On an upper cross-member there are articulated hydraulic cylinders which are articulated to the gripping shells. Between the cross members there is a spacer part with a stop. By actuation of the hydraulic cylinders, the gripping shells are opened or closed.DD 62784 A5 relates to a universal excavator with hydraulic drive, which forms a crane with two-cable grippers or cable scraper. The two-rope gripper or rope scraper is suspended on a boom from a pull rod.DE 76 13 642 U relates to a tong gripper. The tong gripper has two cross-pieces arranged one above the other, which are movable relative to one another by a movement mechanism. Angle-shaped gripper tongs and a supporting cable are fastened to these cross-pieces. The main function of this construction is that the gripper tongs can be moved during the opening and closing process via articulated rods which are connected to a cross member. The gripper tongs execute a circular movement about their fastening points, while one of the cross-pieces executes a vertical movement. This arrangement prevents the prongs of the tongs from penetrating into the ground when the material is being picked up, by describing a flatter path which approximates a plane. The movement of the cross members can be effected either by a screw spindle and a nut or hydraulically, the drive being controlled by an electric motor or hydraulically.DE 603 166 A describes a motor gripper which is constructed by means of cross members, closing rods and gripper arms. The drive is effected by a motor which drives the drum, a cable of which is guided over a plurality of rollers and finally fed back to the drum. The central element of the art is an axially slidable brake lock held by a spring in frictional engagement with gear parts to minimize the run-out of the drive. The locking mechanism is equipped with an adjustable spring, which makes it possible to adjust the frictional engagement and thus the braking properties.DE 1 223 121 A relates to a mobile crane with a two-rope gripper which for auxiliary gripper operation is equipped with a second rope drum which is hydraulically and manually controlled. The control system includes the control spools for raising and lowering, the operation being effected by hand levers. The clutch and brake of the support drum is electrically operated by sheave sensing rollers which can also turn the entire hydraulic circuit on and off. In addition, there are electrical switches for cases of emergency and overload situations. The construction of the cable drums allows both bulk material and bulk material to be transported efficiently by the closing cable functioning as a retaining cable and vice versa. The mechanism for controlling and operating the clutches and brakes is designed to simplify operation and reduce the wear on the cables.DE 832 198 B describes a motor gripper which is operated with closing ropes which are usually guided over a closing rope drum in order to close or open the rope during the gripping process. In order to avoid the formation of slack rope and the resulting problems such as rope bends and bends, rope guidance is implemented. A central element of this technique is the slack rope switch, which is activated when the rope tension is released and automatically stops the closing motor to control the rope length and ensure orderly rope running. The motor is arranged on a lower cross member. The switch can also function as a limit switch at maximum opening width of the gripper shells, as a result of which additional components such as cable winders become unnecessary. The lap cable switch and cable guide are designed to be installed at various locations along the cable path, and optional elements such as a cable storage or link may be incorporated with a loose pulley or weight slide guide to regulate cable tension.The known machines, excavators or cranes which operate on the basis of cable grippers have the disadvantage that the cables suffer from a relatively great wear. The cables are worn in particular by friction with the deflection rollers and / or the pulley trains. The cables namely transmit the force to the gripping shells and control the gripping.Disclosure of the InventionIt is therefore the object of the invention to avoid the disadvantages of the prior art and in particular to reduce the wear of the cables in cable grippers.According to the invention, the object is achieved in that in the case of a gripping device for a cable gripper of the type mentioned at the beginningf) the drive has a rotatable drive cable drum with a drive cable, wherein the drive cable is driven by the cable gripper and drives the drive drum, whereinThe adjusting device has a cable reel with an adjustable cable that can be wound up or unwound for controlling the distance between the cross members, wherein the cable reel is rotatably mounted in the mounting platform and is coupled to the reduction gear.The invention is based on the principle that the reduction in the transmission of force is no longer dependent solely on relatively long cables which can wear out greatly due to the friction occurring. Rather, a reduction gear is now used which is not subject to wear as much as the cables.An advantageous embodiment of the gripping device according to the invention for a cable gripper has proven to be provided if the drive has a rotatable drive cable drum with a drive cable. This drive cable drum acts on the reduction gear and can be controlled from the distance by a drive cable. In this case, the drive cable drum can be rotated by the cables in two directions about its axis of rotation. This allows opening and closing of the gripping device with relatively large forces.In a preferred embodiment of the gripping device according to the invention for a cable gripper, the adjusting device has a cable reel with an adjustable cable that can be wound up or unwound for controlling the distance between the cross members, wherein the cable reel is rotatably mounted in the mounting platform and is coupled to the reduction gear.A further advantageous embodiment of the gripping device according to the invention for a cable gripper is achieved in that the reduction gear is designed as a gear drive. The gear train consisting of gears is not subject to so great wear. A cable which reduces the forces, for example via a pulley block, must travel over long paths. This also entails correspondingly high friction on the rollers or guides. As a result, the cable wears correspondingly quickly. The gears of the gear drive, on the other hand, are not so susceptible to wear.A further preferred embodiment of the gripping device according to the invention for a cable gripper consists in the fact that the adjusting device has a chain, a toothed rack and / or a spindle for controlling the distance between the cross-members, which are driven via the reduction gear. Preferably, it is to be avoided that cables susceptible to wear are used. Therefore, with this measure, agents are optionally used which are not subject to such high wear. This can be effected, for example, by a chain, a toothed rack and / or a spindle. The combination of these listed means for controlling the distance between the cross members is also possible.An advantageous embodiment of the gripping device according to the invention for a cable gripper further consists in the fact that the mounting platform is provided on the lower cross-member. This measure achieves the effect that the weight of the lower cross-member is increased in order to open the gripping shells. Gravitational forces thus make it easier to open the gripping device with its gripping shells.Further embodiments and advantages result from the subject matter of the dependent claims and from the drawings with the associated descriptions. An exemplary embodiment is explained in more detail below with reference to the attached drawings. The invention is not intended to be limited solely to these exemplary embodiments listed. They serve merely to explain the invention in more detail. The present invention is intended to refer to all items now and in the future referred to by those skilled in the art as being obvious to the practice of the invention. The prior art cited in the publication is included in the disclosure content of the present invention.BRIEF DESCRIPTION OF THE DRAWINGFIG. 1 shows a perspective illustration of an exemplary embodiment of a gripping device according to the invention. FIG. 2 shows an enlarged detail of the gripping device according to the invention according to FIG. 1 with the reduction gearing.Preferred EmbodimentIn FIG. 1, reference numeral 10 designates a gripping device according to the invention. The gripping device 10 is provided for a cable gripper 12. The cable gripper 12 is indicated in this illustration only as a cantilever 14. Here, cable gripper 12 is understood to mean a machine in which the gripping device 10 is held and optionally controlled via cables 16. In this exemplary embodiment, the cable gripper 12 can be, for example, a crane or an excavator. The ropes 16 run over the boom 14 of the rope gripper 12, on the one hand they are support ropes 18 which hold the gripping device 10 and on the other hand they are control ropes 20 with which the gripping device 10 is controlled. With the suspension ropes 18, the gripping device 10 can be pulled up or lowered on the boom 14. For this purpose, the cable gripper 12 has a non-illustrated support cable pulley which rolls up or down the support cables 18.The gripping device 10 comprises a cable suspension 22 with which it is fastened to the holding cables 18. The gripping device 10 contains an upper cross member 24, on which an eyelet 26 of the cable suspension 22 is provided centrally. Closing rods 28 are arranged in a star shape on the upper cross member 24. The closure rods 28 are pivotally mounted by bolts 30 in pivot brackets 32.The gripping device 10 further comprises a lower cross-member 34. gripping shells 36 are arranged in an articulated manner on the lower cross-member 34. For this purpose, the gripping shells 36 are each screwed with their upper gripping shell end 38 in a joint mounting 40 in an articulated manner to the lower cross-member 34 by means of screw bolts 42. At least one closing rod 28 is always connected to a gripping shell 36 in articulated fashion via a joint holder 44 with screw bolts 46.In order to actuate the gripping device 10, the distance between the cross members 24, 34 must be changed as required. To open the gripping shells 36, the distance between the cross members 24, 34 is increased. For closing the gripping shells 36, the distance between the cross members 24, 34 is correspondingly reduced. An actuating mechanism 48 controls the distance between the lower and upper cross-pieces for opening or closing the gripping shells 36.In the present exemplary embodiment, the actuating mechanism 48 is mounted on the lower cross member 34 in a mounting platform 50. The mounting platform 50 is fixed to the lower cross member 24. On the mounting platform 50, as components of the actuating mechanism 48, a drive 52 with reduction gears 54, 56 are arranged. The reduction gears 54, 56 drive an actuator 58 for opening and closing the gripping cups 36. In this case, the adjusting device 58 is operatively connected to the upper cross-member 24 and the lower cross-member 34 in an adjusting manner, such that the distance between the cross-members 24, 34 can be varied.In the present exemplary embodiment, the drive 52 consists of a cylindrical drive cable drum 60 which is rotatably mounted in the mounting platform 50 via a shaft 61 which corresponds to the axis of rotation 61 aof the drive drum 60. The control cables 20 are guided through openings 63 in the upper cross member 24 and drive the drive cable drum 60. Pulleys 65 prevent excessive wear of control cables 20 as they enter openings 63.A first drive cable 20 aand a second drive cable 20 bof the control cables 20 drive the drive drum 60 actively about the axis of rotation 61 ato close the gripping shells 36. By the weight of the gripping device 10, the drive cable drum 60 is correspondingly rotated in the opposite direction for opening the gripping shells 36. Instead of the drive cable drum 60, a motor, such as an electric motor or a hydraulic or pneumatic motor, can alternatively be used to drive the reduction gears 54, 56.The reduction gears 54, 56 are operatively engaged to the shaft 61 laterally of the drive cable drum 60. The reduction gears 54, 56 are coupled to the actuator 58. The adjusting device 58 consists of two cable pulleys 62, 64. the cable pulleys 62, 64 are likewise rotatably mounted in the mounting platform 50. The rope pulleys 62, 64 of the adjusting device 56 wind up and down adjusting ropes 66, 68. The control cables 66, 68 are each anchored with their one end to the upper cross member 24 with holders 70, 72. When the adjusting cables 66, 68 are unwound, the distance of the upper cross member 24 from the lower cross member 34 is increased. As a result, the gripping shells 36 open for gripping. Accordingly, the distance between the cross members 24, 34 is reduced by winding up the adjusting cables 66, 68, so that the gripping shells 36 are closed.FIG. 2 shows an enlarged detail in the region of the actuating mechanism 48 of the gripping device 10, as is illustrated in FIG. 1. Insofar as the two figures correspond, the same reference numerals are also used. As will be seen herein, the actuating mechanism 48 is mounted on the lower cross-member 34 in the mounting platform 50. The mounting platform 50 is attached to the lower cross member 34. The drive 52 is arranged with the reduction gears 54, 56 on the mounting platform 50. The locking rods 28 have not been shown for reasons of clarity.The drive cable drum 60 of the drive 52 is rotatably mounted in the mounting platform 50 via a rotation axis 62. In this case, the control cables 20 drive the drive cable drum 60. The driving parts 20 aand 20 brotate the driving rope drum 60 in the one direction about the rotation axis 61 ato actively drive the gripping shells 36 to close the gripping devices 10, and the driving rope drum 60 is rotated in the opposite direction to open the gripping shells 36.The reduction gears 54, 56 are operatively engaged laterally of the drive cable drum 60 at the rotational axis 61a thereof. The reduction gears 54, 56 are designed as gear drives 74, 76 with gears 78, 80. The gears 78, 80 are also rotatably mounted in the mounting platform 50. The gears 78, 80 mesh with each other in such a way that a reduction of the rotation is transmitted. The reduction gears 54, 56 are coupled to the actuator 58. The cable pulleys 62, 64 of the adjusting device 58 are likewise rotatably mounted in the mounting platform 50. The cable pulleys 62, 64 of the adjusting device 56 wind up and down the adjusting cables 66, 68. The adjusting cables 66, 68 are each anchored with their ends to the upper cross member 24 with holders 70, 72. When the adjusting cables 66, 68 are unwound, the distance of the upper cross member 24 from the lower cross member 34 is increased. As a result, the gripping shells 36 open for gripping. Accordingly, the distance between the cross members 24, 34 is reduced by winding up the adjusting cables 66, 68, so that the gripping shells 36 are closed.List of reference characters10 Gripping device 12 cable gripper 14 boom 16 cables 18 support cables 20 control cables 20 a, 20 bdrive cable 22 cable suspension 24 upper cross member 26 eyelet 28 closing rods 30 screw bolts 32 joint holders 34 lower cross member 36 gripping shells 38 upper gripping shell end 40 joint holders 42 screw bolts 44 joint holder 46 screw bolts 48 actuating mechanism 50 mounting platform 52 drive 54, 56 reduction gear 58 adjusting device 60 drive cable drum 61 shaft 61 arotation axis 62, 64 cable rollers 63 openings 65 deflection rollers 66, 68 adjusting cables 70, 72 holders 74, 76 gear drive 78, 80 gear wheels

Claims

Gripping device (10) for a cable gripper (12), comprising a) a cable suspension (22) to which the gripping device (10) is fastened, b) an upper cross-member (24) of the gripping device (10), on which closing rods (28) are articulated, c) a lower cross-member (34) of the gripping device (10), on which gripping shells (36) are articulated, wherein in each case at least one closing rod (28) is articulated to a gripping shell (36), d) an actuating mechanism (48) which controls the distance between the lower cross-member (34) and upper cross-member (24) for opening or closing the gripping shells (36), e) the actuating mechanism (48) has a mounting platform (50) on which a drive (52) with a reduction gearing (54, 56) is arranged, which drives an adjusting device (58) for opening and closing the gripping shells (36), wherein the adjusting device (58) is operatively connected in an adjusting manner to the upper cross-member (24) and the lower cross-member (34), characterized in that f) the drive (52) has a rotatable drive cable drum (60) with a drive cable (20a, 20b), wherein the drive cable (20a, 20b) is driven by the cable gripper (12) and drives the drive drum (60), wherein g) the adjusting device (58) has a cable reel (62, 64) with an openable and developable adjusting cable (66, 68) for controlling the distance between the cross-members (24, 34), wherein the cable reel (62, 64) is rotatably mounted in the mounting platform (50) and is coupled to the reduction gearing (54, 56).Gripping device (10) for a cable gripper (12) according to Claim 1, characterized in that the reduction gearing (54, 56) is designed as a toothed gearing (74, 76).Gripping device (10) for a cable gripper (12) according to Claim 2, characterized in that the adjusting device (58) has a chain, a toothed rack and / or a spindle for controlling the distance between the cross members (24, 34), which are driven via the reduction gearing (54, 56).Gripping device (10) for a cable gripper (12) according to one of Claims 1 to 3, characterized in that the mounting platform (50) is provided on the lower cross-member (34).

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