EP0070950A1 - Internal grab for lifting loads, especially rolls - Google Patents

Abstract

1. Internal gripping device (1) as load lifter, especially roll lifter, with a connecting means (7) for a supporting apparatus for example a crane hook, also with an expanding mandrel (2) on whose housing (5) a radially projecting bearing contact surface (46) is arranged at the upper region and in whose housing (5) an expanding device is arranged which consists of at least one axially mobile expanding guide (14) converging towards the connecting means, and of radially mobile expanding teeth (19) which abut on said guide, wherein the connecting means (7) is connected to an entrainment element (6) guided to be axially movable in the expanding mandrel housing (5) for the entrainment of the expanding guide (14) after a specific idle travel, and the entrainment element (6) and the expanding mandrel housing (5) are connected by means of a gravity change-over switch for changing-over the expanding device to "expand" when the bearing contact surface comes to bear on the load and for subsequently changing-over to "release" after the load has been set down, characterised in that the gravity change-over switch consists substantially of two parts arranged on the one hand on the entrainment element (6) and on the other hand on the expanding mandrel housing (5), namely a triangular control plate (35) and a control lever (32) which co-operates with the control plate (35) and which is movable in the circumferential direction, the control plate (35) having a substantially circumferentially disposed side (38) provided with a recess (39), and, oppositely, a nose (37) which is directed towards the suspension of the control lever (32) and in the region of which there is arranged a latch (43) for the guiding of the control lever (32) on telescoping of the entrainment element (6) and the expanding mandrel housing (5) in opposition to a force (31) acting on the control lever (32).

Description

The invention relates to an internal gripper as a load lifter, in particular a roller lifter, with a connection means for a carrying device, for example a crane hook, and with an expanding mandrel, on the expanding mandrel housing of which a radially projecting seating surface is arranged in the upper region and in the expanding housing a spreading device are arranged, which at least consist of there is an axially movable spreading cone, which is connected to the connecting means at least when spreading and radially movable spreading teeth abutting against it, an automatic switching device for switching the spreading device to "spreading" when the seating surface is seated on the load and then switched to "loosening" after the load has been set down.

Internal grippers are used to transport loads that have a recess in the area of their center of gravity into which the internal gripper can move. Material loads, for example paper, rolled up on winding cores, in particular, come as loads or plastic sheeting, in question. The inner gripper, which is usually suspended from a crane hook via a suitable connection means, can be lowered for transport into the winding tube, where it is clamped with the winding tube and the load can then be lifted (cf. A. Schmidt, load handler with inner grippers in "conveying and lifting""26th year, No. 3, March 1976, pages 269 to 271).

Various constructions are known for bracing the winding tube and inner gripper. One of these constructions works with spreading teeth that extend radially outwards from the mandrel housing and that lie against the inner wall of the winding tube. The expansion takes place via an expansion cone which is guided axially displaceably in the expansion mandrel housing and is connected to the connection means for the carrying device, for example a crane. When the inner gripper is lifted after it has been inserted into the winding tube, only the expansion cone is initially lifted and thus moves within the expanding mandrel housing. The spreading teeth on it are thereby pushed out and come to rest on the winding tube. When the load is lifted, the spreading teeth are pressed against the winding tube, the higher the weight of the load.

In order to give the expanding teeth an initial tension after insertion into the winding tube, a spring is arranged between the expanding mandrel housing and the extension of the expanding cone, which strives to move the expanding cone relative to the expanding mandrel housing in such a way that the expanding teeth are pressed outwards even without lifting the inner gripper will. However, this requires that the expanding mandrel housing and expanding cone Before moving into the winding tube and after the load has been set down, they have to be pushed together by hand against the action of the spring in order to release the initial tension. At a relatively high load, the operator has to climb up, which creates the risk of an accident. In addition, handling below the crane hook bottle is not permitted.

In a further article by A.Schmidt, lifting and turning rolls without material damage, in "Wochenblatt für Papierfabrikation" lo7.jahrgang, No. 13, 1979, page 5 ₀ 3 to 5o7, a proposal has therefore been made, an internal gripper of the aforementioned Type to be provided with a switching device which automatically switches to "spreading" after the inner gripper has been lowered into the winding tube and "released" after the load has been set down. The operator can therefore bring the internal gripper to the spreading teeth or their loosening in the winding tube solely by controlling the carrying device, so that there is no longer any risk of an accident. Since this is to be done purely mechanically, no external energy is required.

However, this publication does not contain any details about the means by which the automatic switching without external energy is to be effected. The invention is therefore based on the object to provide an internal gripper of the type mentioned with a simple and reliable device that enables automatic connection and disconnection of the internal gripper with or from the load.

This object is achieved in that the connection means with one in the expanding mandrel Housing axially movably guided driving element for driving the expansion cone is connected after a certain idle stroke and that driving element and expanding mandrel housing are connected via a heavy weight changeover switch as a switching device. A heavyweight switch is understood to mean a mechanical switching device which, after the driving element and the expanding mandrel housing have been pushed into one another, initially prevents the two parts from being pulled apart by appropriate latching, but releases the connection again when pushed further together. The former switch position results after a load has been set down, if the driving element lowers due to its own weight into the expanding mandrel housing when the crane hook is lowered further and thereby also moves the expanding cone in such a way that the expanding teeth detach from the winding axis. The inner gripper can then be lifted out of the winding tube. The release position is reached when the internal gripper is lowered again into a winding tube and the seating surface of the expanding mandrel housing comes to rest on the load. When the crane hook is lowered further, the driving element lowers a little further into the expanding mandrel housing, so that the connection between these two parts disengages. During the subsequent lifting, the driving element connected to the crane hook pulls up the expansion cone, so that the expansion teeth are moved outwards against the winding tube, and the more the greater the weight of the load.

In an embodiment of the invention it is provided that the heavy weight changeover switch essentially consists of two on the one hand on the driver element and the other on the part of the expanding mandrel housing parts, namely a triangular control disk and a shift lever which cooperates with the control disk and can be moved in the circumferential direction, the control disk having an essentially circumferential direction with an indentation and opposite a tip directed to suspending the shift lever, in the area of which a pawl for guiding the shift lever when pushing together the driving element and expanding mandrel housing is arranged against a force acting on the shift lever. This design of the heavy weight changeover switch has proven to be particularly simple and reliable. It can also be implemented at a relatively low cost.

The shift lever can, for example, be directed downward from the driving element to the control cam on the expanding mandrel housing. The shift lever expediently has a radially projecting guide pin for abutment on the control disk.

According to a further feature of the invention it is provided that the shift lever is pivotally mounted on a radially extending axis. In this case, the force acting on the shift lever can be gravity, for example by shaping an asymmetrically arranged weight. There is also the option of exerting a spring force on the gear lever.

As an alternative to the pivotable arrangement of a shift lever, this can also be rigidly attached to a guide ring which can be rotated in the circumferential direction against the action of a spring force.

In a further embodiment of the invention, a guide groove for guiding the shift lever into the indentation is provided opposite the indentation of the control disk. A further improvement in the guidance can be achieved in that the control disk is surrounded by a groove in which the shift lever surrounds.

The pawl is expediently designed such that it can be pivoted away by the switching lever when the driving element and expanding mandrel housing are pulled apart. However, the pawl can also be designed as a flat spring projecting from an edge.

According to a further feature of the invention, it is proposed that the entrainment element be designed as an entrainment sleeve which has an inner web for entrainment of an extension of the expansion cone protruding into the entrainment sleeve.

• Fig. 1 einen Längsschnitt durch einen Innengreifer;
• Fig. 2 einen Querschnitt durch den Innengreifer nach Figur 1 in der Ebene IV-IV;
• Fig. 3 eine Teilansicht des Innengreifers gemäß Figur 1 in einer um 9o gedrehten Stellung;
• Fig. 4 einen Längsschnitt durch den Innengreifer gemäß den Figuren 1 bis 3 nach dem Einsenken in eine Papierrolle;
• Fig. 5 eine Teilansicht des Innengreifers gemäß den Figuren 1 bis 4 in der Stellung gemäß Figur 4 in um 9₀° gedrehter Stellung;
• Fig. 6 einen Längsschnitt durch den Innengreifer gemäß den Figuren 1 bis 5 mit angehobener Papierrolle und
• Fig. 7 eine Teilansicht des Innengreifers gemäß den Figuren 1 bis 6 in um 90° verdrehter Stellung.

In the drawing, the invention is illustrated in more detail using an exemplary embodiment. Show it:

• 1 shows a longitudinal section through an internal gripper.
• 2 shows a cross section through the internal gripper according to FIG. 1 in the plane IV-IV;
• 3 shows a partial view of the inner gripper according to FIG. 1 in a position rotated by 90 °;
• Fig. 4 shows a longitudinal section through the inner gripper according to Figures 1 to 3 after ones ken in a roll of paper;
• Fig. 5 is a partial view of the inner hook Figures 1 to 4 in the position shown in figure 4 turned in around 9 ₀ ° position shown;
• 6 shows a longitudinal section through the inner gripper according to FIGS. 1 to 5 with the paper roll raised and
• Fig. 7 is a partial view of the inner gripper according to Figures 1 to 6 in a position rotated by 90 °.

The inner gripper 1 shown in FIGS. 1, 4 and 6 has an expanding mandrel 2 which can be sunk into the winding sleeve 3 of a paper roll 4. The expanding mandrel 2 has a cylindrical expanding mandrel housing 5, in which a driving sleeve 6 is axially displaceably guided. An eyebolt 7 serving as a connecting means for a carrying device, for example a crane with a crane hook, is screwed into the driving sleeve 6 at the top. The inner gripper 1 can thus be hung on the crane hook.

On the right-hand side, the driving sleeve 6 has an anti-rotation device in the form of an axially extending guide groove 8, in which a guide block 10 fixed by means of screws 9 on the inside of the expanding mandrel housing 5 is fixed. This anti-rotation device also has the task of limiting the axial relative movement between expanding mandrel housing and driving sleeve 6.

A support bolt 11 projects into the driving sleeve 6 from below into it, which has at its upper end a thickened guide piston 12 lying against the inside of the driving sleeve 6. As shown in particular in FIG. 6, it can be supported on an inwardly projecting annular web 13 of the driving sleeve 6.

At the lower end of the support bolt 11, an expansion cone 14 is fastened by means of a screw 15. The screw 15 clamps the expansion cone 14 against a hat-shaped spacer sleeve 16, which is supported on a shoulder 17 on the supporting bolt 11.

As the cross section in FIG. 2 in particular shows, the expansion cone 14 has a total of five expansion grooves 18 at equal angular intervals, which taper conically towards one another, that is to say become ever deeper. Spreader teeth 19 are inserted into them, each of which consists of an expansion web 21 encompassing the expansion grooves 18 and an expansion surface 22 formed thereon. The spreading surfaces 22 are so wide in the circumferential direction that there are only slight gaps between them, so the contact surface on the winding tube 3 is relatively large.

In the lower end of the expanding mandrel housing 5, a locking ring 23 is inserted on the inside, on which a hat-shaped disk nut 24 is supported. In the screw 25 is screwed from below, which carries an end cap 26.

In the area of the upper end of the driving sleeve 6, a support web 27 is fastened, on which a pivot ring 28 which is rotatable in the circumferential direction is mounted. Its upward movement is opposed by two countered locknut 29, 3o limited. A tension spring 31 (see FIGS. 3, 5 and 7) acts on the swivel ring 28 in the circumferential direction.

As can be seen in particular from FIGS. 3, 5 and 7, a vertically downward shift lever 32 is rigidly attached to the swivel ring 28 and has a radially inwardly projecting guide pin 33 at its lower end. This engages in a control groove 34 in the driving sleeve 6 of substantially constant width, which has an approximately triangular control disk 35 in the middle. The left side 36 in this view bends from an upper tip 37 in an arc obliquely to the bottom left, where it then merges into a side 38 extending in the circumferential direction. However, this side 38 has a strong indentation 39 upwards. The adjoining right-hand side 40 has a hump 41. Above the hump 41, a flat spring 43 fastened by means of the screw 42 is let into the groove base and rises upwards from the groove base.

The area of the control groove 34 is surrounded by a cover tube 45 which is fastened to the expanding mandrel housing 5 at the bottom via a seat ring 46. This cover tube 45 partially covers a cover pot 47 clamped between the eyebolt 7 and the driving sleeve 6. Both cover tube 45 and cover pot 47 are omitted in FIGS. 3, 5 and 7 in order to make the switching device shown there visible.

The function of this automatically switching interior gripper 1 is designed as follows.

Figures 1 to 3 show the position in which the inner gripper 1 is suspended without load via its eye bolt 7 on a crane hook. The driving sleeve 6 is pushed fairly far into the expanding mandrel housing 5, wherein - as can be seen above all in FIG. 3 - the shift lever 32 is seated in the lower recess 39 of the control disk 35 and in this way holds the expanding mandrel housing 5 raised. Also, the expansion cone 14 is pressed by the driver sleeve 6 via the spacer sleeve 16 as far down that the spreading teeth 19 ^g in the contour of the expanding mandrel 5 ehäuses are retracted. In this form, the inner gripper 1 can therefore be lowered with its expanding mandrel 2 into a cylindrical recess in a load to be transported.

This has been done in FIG. 4 using the example of the winding tube 3 of a paper roll 4. The lowering movement is limited by the landing ring 46. If the crane hook is then lowered a little further, the driving sleeve 6, together with the expanding cone 14, moves even further into the expanding mandrel housing 5 due to its own weight, the position shown in FIG. 4 being reached.

This in turn causes the shift lever 32 and with its guide pin 33 due to its positional run ^g of the driver sleeve 6 after moving down is, and thus moves out of the indentation. 39 Since he or the swivel ring 28 are simultaneously rotated in the circumferential direction by the tension spring 31, he comes - as can be seen in FIG. 5 - into an area of the control groove 34 which moves upwards allows. The inner gripper 1 is thus ready for the pretensioning with the winding tube 3.

This is done by lifting the crane hook or the eyebolt 7. As a result, only the pick sleeve 6 is first pulled up. The guide pin 33 moves up the right part of the control groove 34 along the side 40 of the control disk 35, passes over the flat spring 43 while depressing the upper, bent edge and thus reaches the straight upward section 48 of the control groove 34.

Only now is the lower annular surface of the guide piston 12 seated on the inner shoulder of the annular web 13, so that when the eyebolt 7 and thus the driving sleeve 6 are raised further, the supporting bolt 11 is lifted up together with the expansion cone 14. Because of the conical shape of the expansion slots 18, the expansion teeth 19 are thereby pushed radially outwards and come to rest on the inside of the winding tube 3. The shift lever 32 with the guide pin 33 in the section 48 of the control groove 34 will also move upward, as shown in particular in FIG. 7. The spreading teeth 19 claw into the winding tube 3 and the paper roll 4 can then be raised, as shown in FIG. 6.

When the paper roll 4 is set down, the crane hook is lowered a little further. As a result, the driving sleeve 6 lowers again into the expanding mandrel housing 5 due to its own weight from the position shown in FIG. 6. As soon as its ring web 13 comes to rest on the spacer sleeve 16, the expanding cone 14 is also pressed down when the lowering continues, so that the expanding teeth 19 are drawn in will. With the driver sleeve 6 and the lever 32 moves downwards simultaneously with its _F üh- approximately bolts 33 initially in the straight portion is downwardly out and then retract against the action of the tension spring 31 in the left portion of the cam groove 34, since the right portion is blocked by the upstanding edge of the flat spring 43 at its entrance.

The lowering continues until the driving sleeve 6 and expansion cone 14 have reached their lowest position shown in FIG. 4. The guide pin 33 is then located in a recess 49 in front of a guide cam 5 _0, which prevents further rotation of the switch lever 32 under the action of the tension spring 31st When the inner gripper 1 can now be lifted out, the driving sleeve 6 is pulled out a little from the expanding mandrel housing 5 until the guide pin 33 of the shift lever 32 has entered the indentation 39 in the control disk 35. This position then corresponds to that shown in FIGS. 1 and 3. With further lifting, the expanding mandrel housing 5 is also carried along via the contact of the guide bolt 33 on the control disk 35 and lifted out of the winding tube 3. The cycle can then start again.

Of course, the different positions of the driving sleeve 6 and expanding mandrel housing 5 can also be adjusted by hand by correspondingly displacing the two parts.

In a modified embodiment, the shift lever can also be pivotally mounted on the driving sleeve. The bracing in a scope Direction can - as in the example shown - take place via a spring or solely by gravity by attaching an asymmetrically attached weight to the suspension or by a suspension twisted in the circumferential direction to the control groove. In this way, the shift lever then always strives to pivot in one direction, as is done in the exemplary embodiment shown by means of the pivot ring 28 and the tension spring 31.

With such a pivotable shift lever there is also no need for a control groove, but an attached control disk is sufficient, possibly together with an additional control cam in the same arrangement as in the embodiment shown. Instead of the flat spring, a pivotable pawl can then be provided, which performs the same function.

Claims (13)

1. Internal gripper as a load, in particular roller lifter, with a connection means for a carrying device, for example a crane hook, and with an expanding mandrel, on the expanding mandrel housing in the upper region of which a radially projecting seat surface and in the expanding mandrel housing a spreading device are arranged, which at least consist of an axial movable and with the connection means at least when spreading cone and adjacent to it, radially movable spreading teeth, an automatic switching device for switching the spreading device to "spreading" when sitting on the seat on the load and then switching to "loosening" after the load is set down, characterized in that the connecting means (7) with a driving element (6) which is axially movably guided in the expanding mandrel housing (5) for the entrainment of the expanding cone (14) after a certain idle stroke and that entrainment element (6) and expanding mandrel housing (5) are connected via a heavy weight changeover switch as a switching device. 2. Internal gripper according to claim 1, characterized in that the heavy weight change switch consists essentially of two parts on the one hand on the driving element (6) and on the other hand on the expanding mandrel housing (5), namely a triangular control disc (35) _' and one with the control disc ( 35) cooperating shift lever (32) which can be moved in the circumferential direction, the control disk (35) having a side (38) which runs essentially in the circumferential direction and has an indentation (39) and opposite a tip which is directed towards the suspension of the shift lever (32) (37), in the area of which a pawl (43) for guiding the shift lever (32) when pushing together the driving element (6) and expanding mandrel housing (5) is arranged against a force (31) acting on the shift lever (32). 3. Internal gripper according to claim 2, characterized in that the switching lever (32) of the driving element (6) projects downward to the control cam (34) on the expanding mandrel housing (5). 4. Internal gripper according to claim 2 or 3, characterized in that the switching lever (32) has a radially projecting guide pin (33) for contact with the control disc (35). 5. Internal gripper according to claim 3 or 4, characterized in that the shift lever is pivotally mounted on a radially extending axis. 6. Internal gripper according to claim 5, characterized in that the force acting on the shift lever is gravity. 7. Internal gripper according to claim 5, characterized in that the force acting on the shift lever (32) is a spring force. 8. Internal gripper according to one of claims 2 to 4, characterized in that the switching lever (32) is rigidly attached to a guide ring (28) rotatable in the circumferential direction against the action of a spring force (31). 9. Internal gripper according to one of claims 2 to 8, characterized in that a guide cam (5o) for guiding the shift lever (32) into the recess (39) is provided opposite the indentation (39) of the control disc (35). lo. Internal gripper according to one of claims 2 to 9, characterized in that the control disc (35) is surrounded by a groove (34) into which the shift lever (32) surrounds. 11. Internal gripper according to one of claims 2 to lo, characterized in that the pawl can be pivoted away by the switching lever when pulling apart the driving element and expanding mandrel housing. 12. Internal gripper according to one of claims 2 to lo, characterized in that the pawl is constructed as a flat spring (43) standing up on one edge. 13. Internal gripper according to one of claims 1 to 12, characterized in that the driving element is designed as a driving sleeve (6) which has an inner web (13) for driving an extension (11, 12) of the expanding cone projecting into the driving sleeve (6) (14).

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