JP2004521046A - Telescopic jib for mobile cranes - Google Patents

Abstract

The invention relates to a telescopic boom for a vehicle crane, comprising a base housing (1), which may be mounted to an upper construction on the vehicle crane in a horizontal joint (2), at the lower end thereof and has a further horizontal joint (3), to which a tipping cylinder, for inclination of the telescopic boom, which may be connected to the upper construction, may be connected and several telescopic stages (4-11), running either in each other, or in the base housing (1), all of which may be telescoped by means of a telescoping device (12) directly connected thereto and which may be locked relative to each other in the telescoped position. One of the telescoping stages (4-11) is embodied from two part pieces (4a, b) in the axial direction thereof, as a bending telescopic stage (4), and both part pieces (4a, b) are pivoted together by means of a hinge. The part pieces (4a, b) may be locked together by means of a locking device in respect of their longitudinal axis in a coaxial orientation and in at least one position, bent relative to each other. According to the invention, the hinge and locking device on the bending telescopic stage (4) lie within the internal contour of the next largest telescopic stage (5).

Description

【Technical field】
[0001]
The invention relates to a telescopic jib for mobile cranes having the features of the preamble of claim 1.
[Background Art]
[0002]
A mobile crane with a telescopic jib according to the preamble is known from US Pat. The mobile crane disclosed therein has a lower traveling body with a road traveling device and an upper revolving superstructure rotatably mounted on the lower traveling body about a vertical axis. The upper revolving structure includes a telescoping jib having a base box having a horizontal pivot joint at a lower end thereof for securing to the upper revolving structure. Another pivot joint is located on the underside of the base in a substantially central region of the base. This pivot joint serves to pivotally mount a hydraulic undulating cylinder, which itself is rotatably supported by an upper revolving structure, for erecting the telescoping jib and for holding it at the desired inclination each time during work input. Useful. A number of telescoping jib sections are located within the base box, and the telescoping jib sections are guided telescopically or within the base box (outermost telescoping jib section). The telescoping jib sections can all be advanced from their entry position to the extended position by a telescoping system mainly configured as a hydraulic cylinder and piston system that can be directly connected to the telescopic jib sections to be moved. The telescoping jib portions can be mechanically locked together in the extended position so that they do not slip back when tilted under the action of the load to be lifted or their own weight. One of the telescopic jib portions of the telescopic jib is composed of two sub-pieces having an axial length, and the sub-pieces can be pivoted to each other by a hinge so that bending occurs inside the telescopic jib. By means of the fixing device, the two pieces are coaxially aligned with respect to their longitudinal axis and can be locked to one another in at least one position bent to one another. The fixing device is configured as a hydraulic cylinder-piston unit, and the cylinder is pivotally supported in a bearing table which is externally connected to one of the flexible telescopic jib parts. , So that the piston rod of the cylinder-piston unit is pivotally connected to the holding arm by means of a pivot joint and this holding arm is rigidly connected on the outside to the other part of the bendable telescopic jib. It is located outside on the telescopic jib. On the underside of the bendable telescoping jib part, both parts are connected to each other by an outer hinge. The bendable portion of the bendable telescopic jib is located approximately one fifth above the telescopic jib. Due to the arrangement of the hinges and the securing device, the bendable telescopic jib can only penetrate to the point of bending and into the next larger telescopic jib. Because the permissible transport length of the jib is limited in the shortened state, the telescopic jib and base surrounding the bendable telescopic jib are shorter than comparable mobile cranes without bendable telescopic jib Have been. At the same time, the maximum extension length of the telescopic jib is reduced.
[Patent Document 1] European Patent Application Publication No. 0970914 [Disclosure of the Invention]
[Problems to be solved by the invention]
[0003]
The object of the present invention is to improve a telescopic jib of the kind set forth in the preamble, such that the telescopic length of the jib is clearly increased without having to use an auxiliary jib.
[Means for Solving the Problems]
[0004]
This problem is solved by the features specified in the characterizing part of claim 1. Advantageous configurations of the invention emerge from the dependent claims.
【The invention's effect】
[0005]
The present invention relates to a bendable telescoping jib portion by having the hinges and securing devices of the bendable telescoping jib portion located within the inner contour of the next larger telescoping jib portion. Prevents the drawback of shortening the rear telescoping jib and base. This makes it possible for the bendable telescoping jib to be completely inserted into the next larger telescoping jib by the telescoping device. At the same time, the next larger telescoping jib and the other larger telescoping jib can maintain their full length as in a conventional telescoping jib. Suitably, the hinges and the fixing devices are arranged such that they do not overhang the outer contour previously provided by the respective hollow profiles of the telescopic jib, ie are located inside the hollow profiles.
[0006]
Primarily, the innermost telescopic jib is configured as a bendable telescopic jib. However, it is basically also possible to form the further outer telescopic jib, for example the penultimate or third telescopic jib, so that it can be bent. In any case, it is preferable that the bendable elastic jib portion is disposed within the upper third of the full extension length of the elastic jib.
[0007]
Since there is usually a certain minimum distance between the two telescopic jib sections guided in a telescoping manner, the hinge may extend slightly from the outer contour of the hollow section of the bendable telescopic jib section, It is desirable to place the hinge completely inside the lower surface of the bendable telescopic jib. Advantageously, the hinge has at least one, in particular a pair, of joint pins, each of which cooperates with a joint plate and a joint bifurcation, the joint plate being connected to one of the flexible telescopic jib parts. It is connected, and the joint fork is connected to the other piece.
[0008]
Similarly, the anchoring device is also expediently located completely inward on the top of the bendable telescopic jib, so that the outer contour of the hollow section of the bendable telescopic jib is as little or as little as possible. It is.
[0009]
The fixing device of the telescopic jib according to the invention can also be formed by one or more hydraulic cylinder-piston systems or, for example, by one or more screw spindle transmissions, each of which is a bendable telescopic jib part. Are arranged on the inner surface of both pieces. In this way, a stepless adjustment of the angle between the two pieces can be made possible. But this is usually not necessary at all. Preference is therefore given, within the scope of the invention, to a solution in which the fixing device is configured as a bolt locking system, which is simple, therefore particularly inexpensive and hard to break down.
[0010]
For this purpose, at least one fixing bolt, in particular a pair of fixing bolts, is provided in the fixing device, in order to achieve a coaxially aligned lock by aligning the longitudinal axes of the pieces of the bendable telescopic jib part coaxially. Each of the fixing bolts can be introduced into a coaxial hole of a fixing fork connected to one part and a fixing plate connected to the other part, and can be unlocked and pulled out from the hole. The diameter of the coaxial hole then corresponds to the diameter of the fixing bolt. In this way, a completely reliable standard operation of the bendable telescoping jib part can be guaranteed, i.e. there is no bending of the two parts with respect to each other. In order to fix both pieces in the bent position, the fixing device mainly has a holding plate, which is connected to the holding fork by means of holding bolts, and the holding fork is itself bendable telescopic. Each of the two pieces of the jib portion is firmly connected on the inside to one of the two pieces. Suitably, the holding plate is provided with a slot along its longitudinal axis, the diameter (width) of the slot matches the diameter of the holding bolt, and the holding bolt can slide relatively in the slot. In this case, in the bent position of the two pieces, the two retaining bolts are respectively located on the inner surface of the semi-cylindrical shape at the two end regions of the slot, and thus the axis of this slot is provided. Directional length is designed. Extending both pieces from the bent position to the non-bent coaxial position allows both retaining bolts to slide smoothly within the slot, and extension is possible without disassembling the retaining bolts. At that time, it is naturally impossible to fix the intermediate position of the bending. However, if this is necessary, for example, holding plates with different slot lengths can be used. It would also be basically possible to provide a plurality of axially spaced holes in the holding plate and to insert the holding bolts into the holes at appropriate angular positions. But this would require undesirable assembly expenditures. It is of course possible to use one or more combinations of a holding plate, a holding fork and a holding bolt. However, the use of a single such combination is entirely sufficient.
[0011]
In a preferred embodiment, in the present invention, fixing bolts are respectively fixed to bolt supports that can move in parallel with the axes of the holes of the fixing fork and the fixing plate. The movement of the bolt support can preferably be effected by means of a screw spindle transmission. The drive for the movement of the bolt support can be hydraulic, pneumatic, electric or electromagnetic. However, it is preferable to drive the screw spindle transmission for the bolt support by means of the crank handle, because of the implementation which is particularly simple, difficult to break down and has low expenditures both in terms of construction expenditure and operation. Such a crank handle can be made removable in order to require as little construction space as possible without exceeding the outer contour of the hollow section of the bendable telescopic jib. Preferably, however, the crank handle has a drive shaft which is axially slidably and non-rotatably guided in a corresponding hollow shaft of the threaded spindle transmission. This allows the crank handle to be withdrawn from the interior of the hollow section of the telescoping jib section through a corresponding hole in its side wall and moved to a working position for operation. It is particularly desirable to equip this crank handle with a foldable grip.
[0012]
Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings.
BEST MODE FOR CARRYING OUT THE INVENTION
[0013]
FIG. 1 shows a telescopic jib according to the invention in an axial longitudinal section at two positions. In the upper figure, all the telescopic jib portions 4 to 10 that can be extended from the telescopic jib base 1 have completely entered the base 1. This position corresponds to the transport position of the telescopic jib. In the lower view of FIG. 1, only the innermost telescopic jib part 4 has advanced out of the base box 1 or the next larger telescopic jib part 5 by means of the hydraulic telescopic device 12, and the bend 32 is a bendable telescopic jib part. 4 is exposed between the two pieces 4a, 4b, ie is no longer surrounded by the telescopic jib part 5. The design structure of the bend 32 will be described in more detail later. The base is provided with a pivot joint 2 at its lower (right) end, by means of which the telescopic jib according to the invention is fixed on the upper structure of a mobile crane so that it can swing about a horizontal axis of rotation. can do. Another pivot joint 3 is arranged on the long side surface of the base 1 which can be regarded as a lower surface when in the working position, this pivot joint also has a horizontal rotation axis and connects a hydraulic undulating cylinder. Help to do. With this undulating cylinder, the telescopic jib achieves the required tilt for the task to be fulfilled in each case and holds it under load.
[0014]
2 to 7, the structure and function of the bending portion 32 of the telescopic jib according to the present invention will be clarified in detail. FIG. 2 shows the bending point in a telescopic position in a side view, in which both pieces 4a, 4b of the telescopic jib part 4 are aligned with one another in a coaxial position and are fixed to each other in this position. I have. For this purpose, hinges are arranged on the inner surfaces of the hollow profiles of the two parts 4a, 4b, and as can be seen in particular from FIG. 5, these hinges consist of two joint pins 13a, 13b and two joint plates 14a, 14b. And two joint forks 15a and 15b. The joint plates 14a, 14b are respectively inserted into cavities formed by mutually parallel plate portions of the joint forks 15a, 15b, each having a coaxial hole. The diameter of this hole corresponds to the diameter of each joint pin 13a, 13b. Coupling pins are inserted into these holes and secured axially, thus creating a pivot joint as a permanent hinge. In order to be able to fasten the two pieces 4a, 4b to one another in their coaxial alignment, design measures are taken in the upper part of the hollow profile as fastening devices on its inner surface, which correspond to the hinges on the lower surface. The hinges each include one fixed fork 18a, 18b and fixed plates 17a, 17b introduced into the fixed fork 18a, 18b. The fixed fork 18a, 18b and the fixed plates 17a, 17b have coaxial holes. Further comprises one fixing bolt 16a, 16b which can be introduced into these holes, the outer diameter of which corresponds to the diameter of the holes. 3 and 5, the fixing bolts 16a, 16b are shown in the locked position. Under these conditions, the innermost telescopic jib portion 4 behaves like a conventional integral telescopic jib portion, ie is telescopic. The fixing bolts 16a, 16b are fixed to the upper ends of the bolt supports 23a, 23b on the front side by screw connections, respectively, and the bolt supports have screw holes at their lower ends extending parallel to the longitudinal axes of the fixing bolts 16a, 16b. (FIG. 5). Both bolt supports 23a, 23b are arranged parallel to each other such that both screw holes are coaxially aligned. An adjusting shaft 24 is passed through the screw hole, and the adjusting shaft has two screw portions 25a and 25b corresponding to the screw holes. Both threaded portions 25a, 25b likewise have oppositely oriented leads in both threaded holes. Therefore, turning the adjustment shaft 24 moves both bolt supports 23a, 23b either closer or farther depending on the direction of rotation. In this way, the fixing bolts 16a, 16b can be pulled out or drawn into the holes of the fixing plates 17a, 17b and the fixing forks 18a, 18b as required. To prevent the bolt supports 23a, 23b from rotating together with the adjustment shaft 24, the bolt supports are relatively non-rotatable in the slots 27a, 27b (FIGS. 5 and 7), but are slidable longitudinally. You are being guided. The adjusting shaft 24 is rotatably supported inside the partial piece 4a of the telescopic jib portion 4 so as not to slide in the axial direction. The adjustment shaft 24 has a hollow shaft at the left end, and has a slot 30 extending parallel to the longitudinal axis of the adjustment shaft 24. The drive shaft 28 of the crank handle 26 can be introduced into the hollow shaft portion of the adjustment shaft 24. At its right end, the drive shaft 28 has a driving pin 29 projecting in the radial direction, and this driving pin is inserted into the slot 30. Thus, the entraining pin 29 forms a stop when pulling out the drive shaft 28 from the hollow shaft portion of the adjusting shaft 24. At the same time, this entraining pin 30 provides a non-rotatable connection between the drive shaft 28 and the adjusting shaft 24. In FIG. 5, a wall hole is recognized in the left side wall of the hollow section of the piece 4 a, and this wall hole corresponds to the extension of the crank handle 26. Since the hollow shaft portion 24 has a length corresponding to the axial length of the drive shaft 28, the crank handle 26 can thus be completely retracted into the hollow profile as will be clear from FIG. The grip of the crank handle 26 is advantageously collapsible so that, in the folded state, the obstruction does not overhang the outer contour of the hollow profile.
[0015]
In order for the two pieces 4a, 4b to be able to bend relative to one another in the bending point 32, the locking by the fixing bolts 16a, 16b must be released by an appropriate operation of the adjusting shaft 24. That is, the fixing bolts 16a, 16b must be pulled out from the corresponding holes of the fixing forks 18a, 18b and the fixing plates 17a, 17b. As is clear from FIG. 6, which shows the unlocking position as in FIG. 4, it is of course possible for the fixing bolts 16a, 16b respectively to still protrude into the holes in the portions inside the fixing forks 18a, 18b, respectively. The fixing plates 17a and 17b swing out from the attached fixed forks 18a and 18b when both the partial pieces 4a and 4b are in the bending positions. A corresponding holding device is provided in the upper part of the hollow section of the telescopic jib part 4 in order to fix the two pieces 4a, 4b to one another in the desired bending position in the sense of a stop. The device prevents the angle between the two pieces 4a, 4b from changing beyond a predetermined value under the action of the load to be lifted or the weight of the bent piece 4a. This holding device is centrally located between the two fixed forks 18a, 18b and has two holding forks 21a, 21b fixed to one of the two pieces 4a, 4b, respectively. The holding plate 20 is positioned between the holding forks 21 a and 21 b, and the holding plate is provided with a slot 22, which extends in the direction of the longitudinal axis of the holding plate 20. Each of the two holding forks 21a, 21b has a through-hole, into which a respective one of the holding bolts 19a, 19b is introduced so as to be non-slidable in the axial direction. The holding plate 20 having a slot 22 whose diameter or width corresponds to the diameter of the holding bolts 19a, 19b and which is considerably longer than the axial distance of both holding bolts 19a, 19b (FIG. 3). Is slidably held by holding bolts 19a, 19b. Therefore, as shown in FIG. 4, the two pieces 4a, 4b can swing relative to one another about the common axis of the joint pins 13a, 13b, and in the slot 22 both retaining bolts 19a, Only after reaching the end position 19b is this swinging movement restricted. 2 and 3, the arrangement of the sensor 31 is further clarified, and it can be monitored by this sensor that the crank handle 26 is properly inserted and the shortening of the telescopic jib portion 4 is not prevented.
[0016]
The telescopic jib provided in the configuration according to the present invention allows all of the telescopic jib parts to advance by a common telescopic device, and the bendable portions of the telescopic telescopic jib surround the bendable telescopic jib parts respectively. Since the jib portion is completely penetrable, the length of the telescopic jib, including the length of the base, does not have to be accommodated in any way compared to conventional telescopic jib. The design measures required for this can be purely mechanical and are therefore relatively inexpensive and in any case extremely reliable in operation. This operation can be performed by hand without any problem, since the operation of unlocking the bend requires only a very small expenditure and the bend is relatively rarely necessary. To move the bent telescoping jib section back into coaxial alignment of the two pieces, place the jib tip on the base (eg, the ground) and let the fixing plate and the fixing bifurcated holes align with each other to enter the fixing bolt. It only needs to be lowered further until it can be done. Thereafter, the last part of the telescopic jib can also be completely shortened.
[Brief description of the drawings]
[0017]
FIG. 1 shows a telescopic jib according to the invention in a fully retracted position and in an extended and bent position of the innermost telescopic jib.
FIG. 2 shows a bending portion when co-aligned partial pieces of a bendable telescopic jib.
FIG. 3 is a plan view of a bending portion.
FIG. 4 shows a bent portion when a partial piece of an elastic jib portion is bent.
FIG. 5 is an axial cross-sectional view taken along the line AA of FIG. 2;
FIG. 6 is an axial cross-sectional view taken along the line CC of FIG. 4;
FIG. 7 is a sectional view taken along line BB of FIG. 5;
[Explanation of symbols]
[0018]
Reference Signs List 1 base box 2 pivot joint 3 pivot joint 4 innermost telescopic jib part 4a, 4b innermost telescopic jib part piece 5-11 telescopic jib part 12 telescopic device 13a, 13b coupling pin 14a, 14b coupling plate 15a, 15b Joint fork 16a, 16b Fixing bolt 17a, 17b Fixing plate 18a, 18b Fixing fork 19a, 19b Holding bolt 20 Holding plate 21a, 21b Holding fork 22 Slot 23a, 23b Bolt support 24 Adjustment shaft 25a, 25b Screw part 26 Crank handle 27a, 27b Slot 28 Drive shaft 29 Carrying pin 30 Slot 31 Sensor 32 Bending point

Claims (17)

A telescopic jib for a mobile crane, comprising a base (1), the lower end of which can be supported in a horizontal pivot joint (2) of a superstructure of the mobile crane and other bases. An undulating cylinder for tilting the telescoping jib, which has a horizontal pivot joint (3) and can be connected to the superstructure, is pivotable to this other pivot joint and is further respectively telescopic or to the base (1). ) Having a plurality of telescoping jib parts (4 to 11) guided in a telescopic device (12) which can be directly connected to each telescoping jib part. One of the extendable elastic jib portions (4 to 11) that can be locked and stretchable is configured as a bendable elastic jib portion (4) and has an axial length of two partial pieces (4a, b). , Both parts (4a, b) are hinged Thus, they are pivotable with respect to one another and can be bent in that the pieces (4a, b) are coaxially aligned with respect to their longitudinal axis by a fastening device and can be locked together in at least one mutually bent position. A telescopic jib, characterized in that the hinge and the fixing device of the telescopic jib part (4) are inside the inner contour of the next larger telescopic jib part (5). The telescopic jib according to claim 1, wherein the bendable telescopic jib part (4) is the innermost telescopic jib part among the telescopic jib parts (4 to 11). The telescoping jib according to claim 1 or 2, characterized in that the hinge is arranged on the inside of the lower surface of the bendable telescoping jib (4). The hinge has at least one, in particular a pair, of joint pins (13a, b), the joint pins being connected to one part (4a) of a joint plate (14a, b) and the other part. The telescoping jib according to any one of claims 1 to 3, characterized in that each cooperates with a joint fork (15a, b) coupled to (4b). The telescoping jib according to any of the preceding claims, characterized in that the fixing device is arranged inside on the upper surface of the bendable telescoping jib part (4). 6. The fixing device according to claim 1, wherein the fixing device is formed by one or more hydraulic cylinder and piston systems pivotally mounted on the inner surface of the two pieces (4a, b). Or a telescopic jib according to item 1. 6. The device according to claim 1, wherein the fixing device is formed by one or more screw spindle transmissions which are pivotally mounted on the inner surfaces of the two pieces (14a, b). The telescopic jib according to 1. The telescoping jib according to any one of claims 1 to 5, wherein the fixing device is configured as a bolt locking system. At least one fixing bolt, in particular a pair of fixing bolts (16a, b), is provided in the fixing device, and the longitudinal axes of the pieces (4a, b) are coaxially aligned to lock the lock in this alignment. To achieve this, the fixing bolts are respectively introduced into the coaxial holes of the fixing bifurcation (18a, b) connected to one part (4a) and the fixing plate (17a, b) connected to the other part (4b). 9. The telescoping jib according to claim 8, wherein the jib is unlockable and can be unlocked and withdrawn from the hole. The fixing device has a holding plate (20) for fixing the two pieces (4a, b) in the bent position, and this holding plate is held by holding bolts (19a, b), respectively, in a fork (21a, b). 10. The telescopic jib according to claim 8, wherein the retaining bifurcation is secured inside each one of the two pieces (14 a, b). 10. The telescopic jib according to claim 10, characterized in that the holding plate (20) has a slot (31) in which the holding bolts (19a, b) are slidable. The fixing bolts (16a, b) are fixed to one bolt support (23a, b), respectively, and the bolt support is fixed to the fork (18a, b) and the axis of the hole of the fixing plate (17a, b). The telescoping jib according to any one of claims 8 to 11, wherein the telescoping jib is movable in parallel with the jib. The telescopic jib according to claim 12, characterized in that the bolt support (23a, b) is movable by a screw spindle transmission (24,25a, b). The telescopic jib according to claim 12 or 13, characterized in that the bolt support (23a, b) is movable by a hydraulic, pneumatic, electric or electromagnetic drive. The telescoping jib according to claim 13, characterized in that said screw spindle transmission (24, 25a, b) is rotatable by a crank handle (26). The crank handle (26) has a drive shaft (28) which is axially slidably and non-rotatably guided in a corresponding hollow shaft (adjustment shaft 24) of the screw spindle transmission. The telescoping jib according to claim 15, characterized in that: The telescopic jib according to claim 15 or 16, characterized in that the crank handle (26) has a foldable grip.