EP0984895A1

EP0984895A1 - Crane with telescope jib

Info

Publication number: EP0984895A1
Application number: EP98934847A
Authority: EP
Inventors: Klaus Conrad; Thomas Krebs; Michael Irsch; Jens Fery
Original assignee: Mannesmann AG
Current assignee: Demag Mobile Cranes GmbH and Co KG
Priority date: 1997-05-28
Filing date: 1998-05-27
Publication date: 2000-03-15
Anticipated expiration: 2018-05-27
Also published as: US6189712B1; ATE216350T1; JP4068161B2; JP2001526615A; WO1998054081A1; EP0984895B1; DE29824453U1

Abstract

A crane includes a telescopic jib having telescopic jib sections and a base jib. The telescopic sections are arranged so that they can be axially moved into and out of the base jib individually. Locking pins are used hold the telescopic sections in place once they are in the required position. A hydraulic piston-cylinder unit arranged in the telescopic jib can push or pull individual jib sections when the respective locking bolts are removed. The movable portion of the piston-cylinder unit has two securing and locking units located at opposing ends of the movable portion. To move the jib section, one of the securing and locking units is connected to the jib section to be moved and the movement of the movable portions pushed or pulls the telescopic section. Once the jib section is moved to a desired position, the locking pin is reinserted to hold the position of the jib section. Since there are two securing and locking units, the piston-cylinder unit is approximately half the length of the telescopic section.

Description

Crane with a telescopic boom

description

The invention relates to a crane with a telescopic boom according to the preamble of claim 1.

In a crane with a telescopic boom known from EP 0 661 234 A1, its individual telescopic shots can be extended and retracted with only a single-stage piston-cylinder unit after releasing locking bolt connections and spring-loaded in the respective extended or retracted positions by towards their locked positions Bolted locking bolt. The piston rod of the single-stage piston-cylinder unit is articulated on the extension link piece that closes the inner end of the outer shot. A driver device, which can be coupled with receptacles of the telescopic shots, is arranged in the region of the end of the cylinder from which the piston rod emerges. The driver device consists of a hydraulic block with opposing cylinders for the retractable and retractable bolts formed by their pistons locking the respective shot and a hydraulic piston-cylinder unit arranged perpendicular to it for actuating the respective

Locking bolt. The hydraulic elements of the driver device are operatively connected so that the radial piston-cylinder unit can only be actuated to retract the respective locking bolt if the driver device is coupled with the out or bag-telescoping weft over the locking bolts.

A comparable telescopic system is known from EP 0 754 646 A1. It consists of a basic shot and at least two telescopic shots relative to the basic shot. In their respective positions, the shots become releasable plug pins which penetrate the walls of adjacent shots (Locking bolt) fixed. The telescopic system furthermore has a lifting cylinder which is delimited by the shots, preferably a single-stage lifting cylinder which can be pressurized on both sides. This lifting cylinder is provided with drivers which can be brought into active engagement with the weft to be displaced in each case. As in the previously described prior art, the piston rod is the

Piston cylinder unit hinged to the inner end of the outer shot. Both known proposals have the disadvantage that the oil supply to the piston-cylinder unit takes place on the inside and long distances are required for the return to the tank with the corresponding formation of turbulence. This reduces the speed when telescoping. In addition, the in the

The amount of oil in the piston-cylinder unit increases the main boom head weight, which means a reduction in the usable load.

DE 31 25 603 A1 discloses a telescopic boom with a basic boom and three telescopic sections which can be retracted and extended directly or indirectly via chain drives by means of a single-stage piston-cylinder unit. The rear end of the cylinder housing of the piston-cylinder unit is articulated on the inner end of the basic boom. The piston rod is connected at the front end via a bolt to a cylinder box comprising the extended piston rod, which is connected to the side walls of the first telescopic section by a bolt near its inner end. The disadvantage of this construction is that all three telescopic sections can only be retracted and extended together and that only one telescopic section can be specifically retracted and extended.

The object of the invention is to provide a crane with a telescopic boom, which is inexpensive to manufacture by maintaining a principle of individual telescoping of the shots by means of a piston-cylinder unit and enables a higher telescopic speed compared to the known prior art and whose usable load capacity is higher.

This object is achieved on the basis of the preamble in conjunction with the characterizing features of patent claim 1. Advantageous further developments are part of subclaims. In contrast to the known prior art, a locking and locking unit is attached to the inner and outer end of the displaceable element of the piston-cylinder unit, which can be coupled to recesses in the telescopic shots. The displaceable element of the piston-cylinder unit can optionally be the cylinder housing, in which case the piston rod is articulated with its rear end to the inner end of the basic boom - or the piston rod - in this case, the cylinder housing is articulated with its rear end to the inner end of the basic boom. In both cases it is advantageous that the length of the piston-cylinder unit is only about 50% of the length of the main boom due to the arrangement of two securing and locking units. A shorter piston-cylinder unit means a shorter kink length, so that the piston-cylinder unit can be dimensionally more favorable with the same lifting force. This in turn has a direct effect on the weight, which despite the additional weight is lower due to the arrangement of the second locking and locking unit compared to a 100% length. For the

Telescoping every single telescopic shot requires two strokes, but since the stroke is only 50%, the total stroke is the same as that of a long piston-cylinder unit. The arrangement is preferably selected with a cylinder housing articulated on the basic boom, in which the piston rod is connected to a guiding and pulling device lying parallel to the piston-cylinder unit, on the inner and outer ends of which the two securing and locking units are fastened. The guiding and pulling device consists of a cross bar attached to the front end of the piston rod, and two guide elements located on the right and left of the cylinder housing. The front end of the guide elements is connected to the cross bar on the one hand and the front end region of the guide elements to the second securing and locking unit on the other hand and the rear ends to the first securing and locking unit. The cross member preferably has a flat profile stiffened with a web plate and the guide elements consist of box profiles with internal sheet metal reinforcements.

The securing and locking unit arranged at the inner end has a bush which is displaceable on the cylinder housing of the piston-cylinder unit and is connected to the two guide elements. A sliding piece is slidably arranged on this bushing, which is mechanically guided by guide grooves and guide rings is in operative connection with the two safety bolts and the gripper. The arrangement of guide grooves and guide rings is chosen so that pulling the respective locking bolt is only possible if the two locking bolts are inserted into the respective lateral recesses of the telescopic sections and conversely, the two locking bolts can only be moved out of the respective recesses if the respective locking bolt is set. The actuating element for the sliding piece is preferably a piston-cylinder unit connected to the guide elements. This piston-cylinder unit is arranged parallel to the cylinder housing of the piston-cylinder unit moving the shots. In the case of the locking and locking unit arranged at the outer end, there is no need for a socket. The other elements are congruent. In addition to the recesses provided at the inner and outer ends, the wefts also have recesses in the middle area for setting the locking bolts. These additional recesses are preferably arranged one above the other at approximately 50% of the length of the shots. This means that for a pushing in or pushing out up to about 50% of the length, the locking via the locking and locking unit arranged at the inner end and for the further pushing in or pushing out between 50-100%, the locking using the one at the outer end arranged locking and locking unit takes place.

The preferred construction for the telescoping of the shots using a known piston-cylinder unit has the advantage that it can be manufactured inexpensively and has good guidance with regard to the securing and locking unit. In addition, the oil supply to the

Piston-cylinder unit facilitated by the fact that the bottom-side oil supply can be realized with the cylinder housing directly at the end of the basic boom. As a result, the amount of oil in the cylinder housing with hydraulic connections that have a large nominal diameter can be returned to the hydraulic tank in the shortest possible way without turbulence, which is conducive to an increase in speed during the telescopic operation. The center of gravity of the extended main boom shifts to the main boom base point due to the weight of the hydraulic oil in the cylinder, which means a reduction in the main boom head weight and thus an increased payload. Advantageous is also the mechanical lock, which is unaffected by electrical or hydraulic interference.

In the drawing, the telescopic boom designed according to the invention is explained in more detail using an exemplary embodiment. Show it:

Figure 1a, b in longitudinal section a retracted telescopic boom designed according to the invention Figure 2a shows a side view in the direction X in Fig. 1a

Figure 2b is a plan view in the direction X in Fig. 1a

Figure 3 is a perspective view of a partially cut telescopic boom

Figure 4 shows the individual stages of the retracted telescopic boom (a) to

Stage of the partially extended telescopic boom (d) FIG. 5 shows a section in the direction A-A in FIG. 4 (lock pulled)

6 shows a section in the direction A-A in FIG. 4 (locking bolted)

According to FIGS. 1 a, b and 2 a, b, a plurality of telescopic sections 2 - 5 are mounted in an axially displaceable manner in a basic boom 1 equipped with an oval cross section. Such a unit can be used as a telescopic boom for stationary or mobile cranes. In this exemplary embodiment, the telescopic sections 2-5 can be telescoped by means of a single-stage piston-cylinder unit known per se. In contrast to conventional designs, it is not the piston rod 16 (FIG. 2 b) but the cylinder housing 6 that is articulated on the extension link 18 that closes the basic boom 1 by means of a bearing 7. In the first to fourth telescopic sections 2 - 5, a locking bolt 2A - 5A is provided in the area of the rear bearing, via which the telescopic sections 1 - 4 are connected to one another. In addition, each telescopic section 2-5 has a recess 2B, 2B '- 5B, 5B' on both sides. A securing bolt 13, 13 'can be inserted into this recess by means of the securing and locking unit 8.1 explained in FIG. 3. On both sides of the cylinder housing 6, a guide element 9, 9 'is arranged, which are connected at the front end via a cross member 11 stiffened with a web plate 30. A support roller 12 is attached in the area of the cross member 11 for support. For the Rope guides, not shown, are provided on the head piece 19 of the basic boom 1 head rollers 15, 15 '. According to the invention, a second securing and locking unit 8.2 is arranged on the one-stage piston-cylinder unit here at the outer end. It is congruent with the locking and locking unit 8.1 arranged at the inner end, the drive 14 facing the inner end of the telescopic boom. The hydraulic supply to the respective drive of the two securing and locking units 8.1, 8.2 takes place via a control and bladder accumulator unit 35.1, 35.2. Depending on the length of the piston cylinder unit moving the sections 2-5, the two control and bladder memory units 35.1, 35.2 can be combined to form a block. For the

Power supply 17 of the respective locking and locking unit 8.1, 8.2, a guide structure 10 is arranged on the underside of the piston-cylinder unit.

Figure 3 shows a perspective view of the details of the interior

End arranged locking and locking unit 8.1. It consists of a bushing 28 which is displaceably arranged on the cylinder housing 6 of the piston-cylinder unit and which is connected to the end regions of the guide elements 9, 9 '. The connection is made via bolts 26.1, 26.2 - 26.1 ", 26.2" (Figure 2a, b). A sliding piece 21 is slidably arranged on the bushing 28. The displacement takes place via a piston-cylinder unit 14 lying parallel to the cylinder housing 6, which in turn is firmly connected to the bushing 28. On the sliding piece 21, a web plate 29, 29 'lying in the horizontal plane is arranged on the right and left, which is provided with a guide groove 27, 27'. This guide groove 27, 27 'acts together with a guide ring 22, 22' connected to the respective securing bolt 13, 13 '(FIGS. 4, 5). The two opposing securing bolts 13, 13 'can be moved into and out of the respective lateral recesses 2B, 2B' - 5B, 5B '(FIGS. 4, 5). A fork plate 31 with a guide ring 23 is provided on the sliding piece 21 perpendicular to the two web plates 29, 29 '. This guide ring 23 interacts with a guide groove 33 arranged on the gripper 24. The gripper 24 is guided in a bushing 32 in accordance with the representations in FIGS. Proximity switches 25, 25.1, 25 ', 25.1', 25.2, 25.3, 25.2 ', 25.3' are arranged in pairs in the upper area of the sliding piece 21. These signal when moving the locking and locking unit 8.1 along the Zyiindergehäuses 6 an approach to one of the side recesses 2B, 2B '- 5B, 5B'.

The individual steps in telescoping are shown in Figure 4 in the sequence of steps a - d. The sequence of steps a) is identical to the illustration in FIG. 1a, b, so that there is no need to repeat the description. To extend the piston cylinder unit is actuated and the piston rod 16 together with the guide elements 9, 9 'moved to the left. To extend the innermost telescopic section 5, the securing and locking unit 8.1 arranged at the inner end is moved along the cylinder housing until it can be coupled to the corresponding locking bolt 5A. Before the locking of the fourth telescopic section 5 with the third telescopic section 4 can be released, the securing bolts 13, 13 'are pushed into the lateral recesses 5B, 5B' provided for this purpose, as shown in FIG. In this way, the securing and locking unit 8.1 is bolted to the innermost telescopic section 5.

According to the sequence of steps b) in FIG. 4, the innermost telescopic section 5 is partially pushed out by moving the piston rod 16 to the left. The sequence of steps b) shows the final state of this first extension phase. The locking bolt 5A of the innermost telescopic section 5 is then inserted into the recess 34.1 located approximately in the middle of the third telescopic section 4. In this way, the partially extended innermost telescopic section 5 is locked with the third telescopic section 4.

Step sequence c) shows the final state of retraction of the locking and locking unit 8.1 and the engagement of the locking bolt 5A of the fourth telescopic section 5 by the second locking and locking unit 8.2 arranged according to the invention at the outer end of the piston-cylinder unit. Before this lock can be released, however, the securing bolts 13, 13 'are pushed into the lateral recesses 5B, 5B' provided for this purpose. In this way, the second securing and locking unit 8.2 is bolted to the innermost telescopic section 5.

Step sequence d) shows the final state of the full extension of the innermost telescopic section 5 after activation of the piston-cylinder unit. To lock the fourth telescopic section 5 with the third telescopic section 4, the Locking bolt 5A into the corresponding receptacle of the third telescopic section 4. At the same time, the two securing bolts 13, 13 'are moved out of the lateral recesses 5B, 5B'. The movable part of the piston-cylinder unit then moves back into the starting position, comparable to the sequence of steps a).

For reasons of space and because of the repetition of the procedural steps, the representation and description of the extension of the other telescopic sections 2-4 were dispensed with.

Figure 5 shows a section in the direction A-A in Figure 4. This representation in connection with Figure 4 shows a situation where the innermost telescopic section 5 is bolted to the locking and locking unit 8.1 arranged at the inner end. For this purpose, the securing bolts 13, 13 'arranged in the securing and locking unit 8.1 are moved to the right and to the left into the recesses 5B, 5B' arranged in the innermost telescopic section 5. Through this bolting, the innermost telescopic section 5 is bolted to the piston-cylinder unit via the locking and locking unit 8.1. The locking bolt 5A is then pulled out of the upper recess 34.1, so that the innermost telescopic section 5 can be pushed out by moving the piston rod 16.

Figure 6 shows the same section AA in Figure 4, only with the difference that the locking bolt 5A of the innermost telescopic section 5 is inserted into the upper recess 34.1 of the third telescopic section 4. Accordingly, the safety bolts 13, 13 'are moved out of the lateral recesses 5B, 5B' by the mechanical coupling described in FIG.

Reference list

Claims

claims

1. Crane with a telescopic boom, the shots (2-5) of which are arranged in a basic boom (1) and can be telescoped individually after releasing locking bolt connections (13, 13 ') with a hydraulic piston-cylinder unit, which can be extended and retracted - or retracted positions are bolted by locking bolts (2A - 5A), characterized in that a locking and locking unit is attached to the inner and outer end of the displaceable element (6, 16) of the piston-cylinder unit, which has recesses (2B, 2B ') - 5B, 5B ', 34.1 - 34.4) of the telescopic shots (2-5) can be coupled.

2. Crane according to claim 1, characterized in that the piston rod of the piston-cylinder unit is articulated with its rear end at the inner end of the basic boom (1) and the two securing and locking units at the inner and outer end of the displaceable

Cylinder housing (6) are arranged.

3. Crane according to claim 2, characterized in that the respective locking and locking unit from a hydraulic block with opposing cylinders for the retractable and extendable formed by their pistons, the respective shot (2-5) locking bolt and a perpendicular thereto arranged hydraulic piston-cylinder unit for actuating the respective locking bolt (2A - 5A).

4. Crane according to one of claims 1-3, characterized in that the radial piston-cylinder unit for pulling in the respective locking bolt (2A - 5A) can only be actuated when the respective The locking and locking unit is coupled with the extracting or retracting shot (2 - 5) over the locking bolts.

5. Crane according to claim 1, characterized in that the cylinder housing (6) of the piston-cylinder unit is articulated with its rear end at the inner end of the basic boom (1) and the piston rod (16) at the front end with a guide and parallel to the piston-cylinder unit Pulling device is connected and the two securing and locking units (8.1, 8.2) are arranged at the inner and outer ends of the guiding and pulling device and for setting the locking bolts (2A - 5A) the shots (2-5) except those on the inner and outer End recesses also have recesses (34.1-34.4) in the middle area.

6. Crane according to claim 5, characterized in that the additional recesses (34.1 - 34.4) are arranged one above the other at approximately 50% of the length of the shots (2-5).

7. Crane according to claim 5 and 6, characterized in that the guiding and pulling device comprises a cross member (11) attached to the front end of the piston rod (16) and two guide elements (9, 9) lying on the right and left of the cylinder housing (6) '), the front end of which is connected to the cross bar (11) on the one hand and the front end area of which is connected to the second securing and locking unit (8.2) on the other hand and the rear ends of which are connected to the first securing and locking unit (8.1).

8. Crane according to claims 5-7, characterized in that the cross member (11) consists of a stiffened with a web plate (30) flat profile.

9. Crane according to one of claims 5-8, characterized in that the guide elements (9, 9 ') are designed as box profiles.

10. Crane according to claim 9, characterized in that the box profiles are provided on the inside with stiffened sheets.

11. Crane according to one of claims 5 - 10, characterized in that the securing and locking unit (8.1) arranged at the inner end has a displaceable on the cylinder housing (6) bushing (28) with the two guide elements (9, 9th ') is connected and both securing and locking units (8.1, 8.2) have a sliding piece (21) connected to an actuating element, which is mechanically operatively connected to two securing bolts (13, 13') and the gripper (24).

12. Crane according to claim 11, characterized in that on the sliding piece (21) on the right and left in each case one in a horizontal plane and provided with a guide groove (27,27 ') web plate (29,29') is arranged, the guide groove ( 27, 27 ') cooperates with a guide ring (22, 22') arranged on the respective securing bolt (13, 13 ') and that one with a perpendicular to the two web plates (29, 29')

Guide ring (23) provided fork plate (31) is arranged on the sliding piece (21), the guide ring (23) cooperating with a guide groove (33) arranged on a gripper (24) guided in a bushing (32).

13. Crane according to claim 11 and 12, characterized in that each guide groove (27, 27 ', 33) has an oblique and a section parallel to the direction of movement of the sliding piece (21), the sequence of oblique and parallel sections the Guide grooves (27, 27 ') of the two web plates (29, 29') are reversed in the sequence in the guide groove (33) of the gripper (24).

14. Crane according to one of claims 11 - 13, characterized in that the actuating element for the sliding piece (21) is a piston-cylinder unit (14) connected to the respective securing and locking unit (8.1, 8.2).

15. Crane according to claim 14, characterized in that the respective piston-cylinder unit (14) lying parallel to the cylinder housing (6) of the shots (2-5) moving piston-cylinder unit is arranged.