IE62601B1 - Suction lifter for lifting and laying of concrete components - Google Patents

Abstract

A suction device for lifting and laying paving stones using suction plungers which can be moved axially and at an angle is designed in such a way that the stones to be laid can be shifted by at least half a stone length relative to one another in order to form a stone bond.

Description

SuCTXON LIFTER FOR LIFTING AND LAYING OF CONCRETE COMPONENTS The invention relates to a suction lifter for lifting and laying material having a high specific weight, for example, for lifting concrete members and concrete blocks and also clinkers and natural paving stone, having a number of axially and angularly movable suction plungers which are constructed in the form of bellows and which are disposed on the underside of the suction lifter and engage around the individual members.

Paving blocks, more particularly bonded blocks, are increasingly being laid by machines. These are selfpropelled devices with running gear and a rectangular suction lifter, attached at least to at least one adjustable jib, for lifting and moving the paving blocks, as disclosed more particularly in German Patent Specifications 32 43 045; 33 24 441; 33 42 424 and European Patent Application 84 101 823.7. Their use makes it possible for the first time to produce economically large areas of bonded blocks which can be driven over by vehicles. However, the suction lifter of such an apparatus is only able to lift bonded block units produced in the works and to perform block laying without any change in the position of the individual rows of blocks.

Attempts are made at the works to load as completely as possible the moulds in which concrete blocks are produced. Blocks not connected to one another by a positive connection can be produced with cross30 joints. However, cross-joints are undesirable for laid bonded blocks, since cross-joints may lead more quickly to a loosening of the bonding. More particularly in the case of blocks for rubble walls, over which water is flushed at least at times, cross-joints enable the water to flush out and under the joints in the blocks more easily. Cross-joints do not offer adequate resistance to the flow of water, so that the regulations require 2 6 01 blocks which are flushed over by water to be set in stretcher courses - i.e., the rows of blocks must be laid off-set in relation to one another. The layers of blocks with cross-joints taken out of the manufacturing moulds are therefore unsuitable for direct mechanical laying using the known apparatus . However, there are limits to manual work in the case of large blocks such as, for example, blocks for rubble walls which, to perform their task adequately, must be as large and heavy as possible and reach weights of more than 50kg.

It is an object of the invention to provide a suction lifter of the kind specified which enables layers of blocks produced with cross-joints and supplying it to the building site while maintaining said joint structure to be lifted and laid in stretcher courses.

This problem is solved according to the invention by the features that the suction plungers are disposed on the undersides of a number of elongate hollow sections, which are disposed one beside the other and in which there is a vacuum, each second hollow section being constructed to slide in the longitudinal direction by at least one half length of a block.

Accordingly, the present invention provides a suction lifter for lifting and laying having a high specific weight, for example, for lifting concrete members and concrete blocks and also clinkers and natural paving stone, having a number of axially and angularly movable suction plungers which are constructed in the form of bellows and which are disposed on the underside of the suction lifter and engage around the individual members, characterized in that the suction 2a plungers are disposed on the undersides of a number of elongate hollow sections, which are disposed one beside the other and in which there is a vacuum, each second hollow section being constructed to slide in the longitudinal direction by at least one half length of a block.

Such a suction lifter enables the laying apparatus to shift individual rows of blocks by at least half a block length after a course with cross-joints has been lifted. As a result, more particularly the large, heavy blocks for rubble walls can also be laid in stretcher bonding by machines. In the case of a suction lifter comprising, for example, five suction rows, the two outer ones and the central one can be constructed rigid, while the two suction rows situated therebetween can be hydraulically displaced in the longitudinal direction. The three rigid hollow sections with their suction plungers are inter-connected via hollow transverse sections in which there is also the vacuum required for lifting the blocks. Connections for the vacuum generator extend from the transverse sections. The facing sides of the hollow sections are furnished with supporting strips which engage in one another, thereby supporting the displaceable hollow sections disposed between the rigid sections. The vacuum connections between the displaceable hollow sections and the rigid sections can be made by flexible lines, for example, pressure hoses.

If the suction level has aligning jaws, these are disposed on three sides. The movable hollow sections with the suction plungers can be advanced over the side free from aligning jaws. Both the rigidly secured and also indirectly the displaceable hollow sections are carried by the transversely directed hollow sections.

The hydraulic adjusting cylinders for the adjusting force required for displacement can be disposed on the top side of the hollow sections.

A separate control system, for example, a manual control system can of course be used for the adjusting cylinders which displace hollow sections, to enable the movement required for the formation of the stretcher bonding to be initiated at any time during the opened position of the aligning jaws. Particularly advantageously, however, they are shunt connected to the adjusting cylinders of the aligning jaws or to their pressure lines. As a result the movement of the hollow sections can be initiated automatically after the opening of the aligning jaws. As soon as the latter have reached their top abutment position, the maximum hydraulic pressure then set up is propagated via the shunt lines to the adjusting cylinders for the hollow sections, enabling them to be displaced. To ensure that in any case the displacement starts only when the aligning jaws are completely opened, the hollow sections - 4 can be additionally loaded by a spring prestressing counteracting the displacement. The spring prestressing is so strong that it cannot be overcome by the partial pressure of the hydraulic working medium prevailing during the opening movement of the aligning jaws. Use can be made of return springs disposed directly in the adjusting cylinder which load the adjusting pistons in the appropriate direction.

Particularly advantageously the suction openings of adjacent suction plungers discharge into a suction chamber which can be placed on the surface of the material to be lifted and which have a suction face acting in common whose shape can also be adapted to the surface curvature of the material to be lifted. As a result, the spaces between the individual suction plungers can be collected and also included in the particularly operative suction chambers of the suction plungers, thereby enhancing the suction force without increasing the suction performance of the vacuum pumps. The connection of at least two adjacent suction plungers via a suction plate of elastomeric material to a common suction chamber is enough to allow the lifting of, for example, concrete members having, for example, a porous structure, which could hitherto be seized by two suction plungers, but not lifted. Due to the flexibility of the suction plate, the enlarged suction chamber can adapt itself to the surface shape of an object to be lifted, thus achieving higher reliability in the transmission of the suction force.

Further advantageous features of the application are set forth in the subclaims.

An explanation will now be given of embodiments of the invention purely diagrammatically illustrated in the drawings, wherein: Fig. 1 shows diagrammatically an arrangement of a number of parallel hollow sections of which three are fixed and two displaceable, Fig. 2 is an end view of the arrangement shown in Fig- 1, Fig. 3 shows diagrammatically an embodiment ready for use, with the aligning jaws closed, Fig. 4 shows the construction illustrated in Fig. 3 with the aligning jaws opened and two hollow sections displaced in the longitudinal direction to form a stretcher bonding.

Fig. 5 shows an apparatus ready for use (Fig. 4) at a shallower viewing angle, Fig. 6 is a longitudinal section through bellows.

Fig. 7 is a longitudinal section through two suction plungers discharging into a common suction chamber, Fig. 8 is a section, offset through 90°, through one of the two suction plungers and the suction plate (Fig. 7), Fig. 9 shows a suction plate placed on the material to be lifted, in a slightly raised position, and Fig. 10 shows a freely floating load on the suction plate shown in Fig. 9.

Fig. 1 shows diagrammatically five hollow sections to 5 disposed parallel one beside the other. The sections 2 and 4 are disposed for displacement in the longitudinal direction. The rigidly constructed hollow sections 1, 3 and 5 are welded to transverse sections 6 and 7 via welds 8.

The displaceable hollow sections 2 and 4 are carried by the rigid hollow sections 1, 3 and 5. To this end the facing sides of the hollow sections have supporting and guide strips 9 and 10. The supporting and guide strips 9 are disposed on the rigid hollow 'sections, while the strips 10 are disposed on the displaceable hollow sections and frame the rigid supporting and guide strips 9 on both sides. They can be displaced in the longitudinal direction by the force of hydraulic pressure cylinders which are articulated to the transverse section 6 and engage the hollow sections 2 and 4 by their piston rods 13 and 14.

The transverse sections 6 and 7 are also hollow, to distribute the vacuum first uniformly over the rigid hollow sections. To this end connecting openings are provided between the rigid sections and the transverse sections. The central section 3 has a connection opening 15 for a vacuum supplying hose 16. The vacuum in the displaceable hollow sections 2 and 4 is produced via flexible connections 17 and 18 which connect the central, rigid hollow section 3 via openings 19 and 20 to the sections 2 and 4. These sections are formed with connecting openings 21 and 22.

The whole arrangement of sections is framed on three sides by aligning jaws 23 to 25 by which the layers of blocks are precisely aligned prior to lifting by means of suction plungers 27. The blocks have the reference 26 (Figs. 3 to 5), The suction lifter can be suspended pendulumfashion from the supporting head 30 of a lifting arm (not shown) of a conveying vehicle. Disposed, between the supporting head and a supporting yoke 31 of the suction lift is a hydraulically driven pivoting head 32 by which tha suction lever can be pivoted steplessly through 360°, th© pivoting axis always being maintained vertical by the pendulum-like suspension. The supporting yoke is connected by means of suitably dimensioned supporting plates 33 to supporting sheets 34 which can transmit the supporting force to the outer rigid hollow sections 1 and 5 via box-shaped connecting sections 35 (Fig. 5).

Hydraulic piston-and-cylinder units 36, 37 and 38 (Fig. 3) are also provided for opening and closing the aligning jaws 23, 24 and 25. All the hydraulic adjusting cylinders are supplied with the working medium via hydraulic supply lines 40 and 41. Two additional lines 42 and 43 extend to the hydraulic pivoting head 32.

From the supply lines 40 and 41, branches (not shown in detail) extend to the individual adjusting cylinders. The adjusting cylinders for displacing the two movable hollow sections are shunt connected to the supply lines 40 and 41 or shunt connected to a number of lines branching therefrom.

To seize and lift a layer of blocks as shown, for example, in Fig. 3, the suction lifter is placed on the blocks with its suction plungers without vacuum and with the aligning jaws 23 to 25 pivoted upwards. Then the aligning jaws are pivoted downwards and pressed against the blocks, as shown in Fig. 3. Since at first there is no vacuum in the hollow sections or therefore in the suction plungers 27, the blocks can be precisely aligned by the contact pressure of the aligning jaws. After alignment, the vacuum is created in all the hollow sections via the hose line 16 of considerable crosssection and propagated to the suction plungers, pressing the blocks tightly against their bottom edges.

After the vacuum has been set up, the aligning jaws are pivoted upwards. As soon as they reach their top end positions, the pressure in the adjusting cylinders of the aligning jaws rises to its maximum value. At the same time the pressure of the hydraulic working medium in the supply lines 40 and 41 rises to its maximum value and is propagated via the shunt connected supply lines to the adjusting cylinders 11 and 12. The maximum pressure is of a value such that it is able to ensure the displacement of the movable hollow sections 2 and 4 with the blocks suspended therefrom. This appropriate connection of the supply lines for the cylinders 11 and 12 to the adjusting cylinders for the aligning jaws ensures that two rows of blocks are displaced automatically only after the aligning jaws have been pivoted upwards.

After this operation the rows of blocks reach the positions on the hollow cylinders 2 and 4 shown in Figs. 4 and 5. The layer of blocks now forms a stretcher bonding which is more particularly suitable for laying on surfaces over which water washes, since it offers a substantially higher resistance to the loosening attack of the water than a bonding with cross-joints.

Bellows 50 of a suction plunger are attached via a shaft to one of the hollow sections in which there is a vacuum. From this shaft folds 52, 53 and 54 extend as far as an outer cylindrical part 55, possibly made of a stiffer material, to which a closure plate 56 (Figs. 7 to 10) can be joined.

In the zone of the transition from the fold 53 to the fold 54 the wall thickness 57 is smaller than that over the rest of the overall fold zone. Also the diameter D of the outermost fold - i.e., immediately in front of the free end of the bellows - is distinctly larger than the diameter d of the other two folds 52 and 53. Both these steps ensure a reliable angular mobility even when the suction lifter starts to be placed onto the object to be lifted. In addition, the angles determining the folds can differ from one another, for example, increasingly from 55’ for the outermost fold 54, 70’ for the central fold 53, up to 90’ for the topmost fold 52. As a result, at the same time the axial mobility of the folds is differentially staged - i.e., ’bellows constructed in this way have a rigidity which starts from the free end and increases in the upward direction.

Figs. 7 to 10 show an example of the connection of two suction plungers to a common suction plate 58 of an elastomeric - i.e., also flexible material. A suction chamber 59 is formed by this plate in conjunction with a circularly raised edge 60 of sealing material and in conjunction with the surface of the object to be lifted. At its base the plate 58 is formed with a profile of intersecting grooves 61 and 62, thus producing spacing knobs which prevent the flexibility of the plate from making its suction side surface directly abut the material to be lifted, thereby preventing the formation of a uniform field of suction, as shown more particularly in Figs. 9 and 10. They indicate, for example, how by using suction plungers constructed in this way it is possible to seize material for lifting whose surface also consists of a resilient material, for example, packaging material, and which changes when the suction force starts to be transmitted from a slight curvature to a heavy curvature (Fig. 10).

Claims:

Claims (15)

1. A suction lifter for lifting end laying having a high specific weight, for example, for lifting concrete members and concrete blocks and also clinkers and natural paving stone, having a number of axially and angularly movable suction plungers which are constructed in the form of bellows end which are disposed on the underside of the suction lifter and engage around the individual members, characterized in that the suction plungers (26) are disposed on the undersides of a number of elongate hollow sections (1, 2, 3, 4, 5), which are disposed one beside the other and in which there is a vacuum, each second hollow section (2, 4) being constructed to slide in the longitudinal direction by at least one half length of a block.

2. A suction lifter according to Claim 1, characterised in that the immobile sections (1, 3, 5) are attached force-transmittingly to at least two supporting transverse section (6, 7) in which there is also a vacuum, whilst the displaceable hollow sections are retained by the immobile rigid hollow sections by means of lateral supporting and guide strips (9, 10).

3. A suction lifter according to Claims 1 and/or 2, characterised in that the displaceable hollow sections are connected to the rigid hollow sections via flexible lines (17, 18).

4. A suction lifter according to one or more of Claims 1 to 3, characterised in that hydraulic adjusting cylinders (11, 12) are provided for displacing the hollow sections.

5. A suction lifter according to Claim 4, characterised in that the adjusting cylinders are double-acting.

6. A suction lifter according to one or more of Claims 1 to 5, characterised in that the pressure lines of the adjusting cylinders (11, 12) for the displacement of the hollow sections are connected side by side to pressure lines of adjusting cylinders (36, 37, 38) for aligning j aws.

7. A suction lifter according to one or more of Claims 1 to 6, characterized in that the displaceable hollow sections are loaded with a spring prestressing acting contrary to the displacement.

8. A suction lifter according to Claim 7, characterised in that the spring producing the spring prestressing is disposed in the adjusting cylinder for the hollow sections.

9. A suction lifter according to one or more of Claims 1 to 8, characterised in that the wall thickness of the bellows (50) of a suction plunger is thinner at the free end in the transition sone from the last fold but one to the last, outermost fold (54) than the wall thickness of the rest of the bellows, and the diameter of the outermost fold is larger than the diameter of the bellows in the remaining sone of the fold, the diameter of the fold being taken to be the maximum diamerex* (D) in the sone of the convex bulge.

10. A suction lifter according to one or more of Claims 1 to 9, characterized in that a cross-secrional narrowing is provided as a restrictor ( 64) in the operative zone of the supporting suction.©! crosssection.

11. » A suction lifter according to Claim 10, characterized in that at least two joining suction plungers are connected to a common suction chamber whose shape is adapted to the surface curvature of an article to be lifted.

12. A suction lifter according to Claim 11, characterized in that a suction chamber is formed by a plate (58) made of an elastomeric material having a circularly extending projecting edge (60) of sealing material and is connected to the suction plungers via nozzle-shaped air passage openings.

13. A suction lifter according to Claim 12, characterised in that the suction side surface of the plate has a profiling (61, 62, 63).

14. A suction lifter according to Claim 13, characterized in that the profiling is forced by regularly intersecting depressions (61, 62).

15. A suction lifter according to any one of the preceding claims, substantially as herein described with reference to