GB2057036A - Guides for piles and other driven members - Google Patents

Abstract

A pile 9 is guided within a guide frame during the driving operation by rollers 20 of jaws 18 pivoted on support plates 15 so as to be capable of opening to receive a pile entering the guide frame in the direction R. The plates 15 may be swung down when the pile is firmly embedded to permit passage of the driving monkey. <IMAGE>

Description

SPECIFICATION Guides for piles and other driven members This invention relates to the driving of piles, and other members which are guided at least temporarily during the driving operation.

In pile driving, the pile to be driven into the ground is transported to the pile driving apparatus from the adjacent storage area, and raised into an upright position relative to the pile previously inserted and relative to a guide of the apparatus.

Herein, the term "pile" is used to include any elongate member intended to be driven into position by pounding one of its ends. The known guides have not proved altogether satisfactory and it is an object of the present invention to provide a guide arrangement capable of offering reliable guidance for the pile to be driven and of adapting to the cross-sectional shape of the pile, but which nevertheless does not obstruct the device used to apply or transmit force to the pile.

Accordingly, a frame within which the pile is located during the driving operation is provided internally with guides comprising jaws rotatable about axes extending parallel to the longitudinal axis of the frame, each jaw being provided with spaced apart guide rollers so arranged that when the pile is in place within the frame, the guide rollers of both jaws encompass the pile such as to restrain it against movement in the direction perpendicularly to the said axis. Each of the jaws may include a support member which may be likened to a two-armed lever, at least one roller being provided at or adjacent the end of each lever arm, whereby the rollers of both jaws lie at the vertices of a rectangle when viewed along the longitudinal axis of the frame, so that they engage four corners or edges of the pile.Since the jaws may turn about axes parallel to the longitudinal axis of the frame, the jaws may in effect open on one side to admit the pile, and thereafter close to embrace it. Conveniently, the jaws are supported on the frame so as to be movable out of contact with the pile to facilitate the passage of the device used to apply force to the pile.

The invention will now be described in greater detail but by way of example only with reference to the accompanying drawings, wherein: Figure 1 is a diagrammatic side elevation of a pile driving apparatus mounted on an excavator, Figure 2 is a cross-section taken on the line B-B in Figure 1, and Figure 3 is a section taken on the line A-A in Figure 2, to a larger scale.

Referring to the drawings, a hydraulically powered excavator 1 has a jib 2 and an extensible support arm 7 which together support a hydraulic operated pile driving apparatus 3 for driving vertically downwards piles consisting of H-sections 9. Piles of other cross-sections, including for example sheet piles, may be driven using the apparatus with, or without, adaptations which will be apparent to those skilled in the art.

Likewise, it will be appreciated that with, or without, adaptations the apparatus may be used to drive piles at an angle to the vertical. The pile driving apparatus includes a guide or leader frame 4 within which the pile is located during the driving operation and through which is guided a hydraulically actuated monkey 5 for pounding the upper end of the pile. Within the scope of the invention, other means may be used to drive the pile into the ground, including a conventional drop hammer.

Connected to the monkey is a winch or other device 6 for attachment to the pile in order to draw it into an upright position within the frame 4.

The frame 4 consists of an open framework which is rectangular in cross-section with longitudinally extending beams 4a arranged at its corners. The rear side of the framework, i.e. that nearer the excavator, is constituted by transversely extending beams 4b and the lateral sides of the framework by similar beams 4c, all of which beams 4b and 4c are rigidly joined to the beams 4a. The front side of the framework is formed by hinged doors 11 which may be opened by rams 12 formed by hydraulically operated piston and cylinder units in order to permit a pile to be introduced into the frame in direction R, as well as during maintenance or repair work. All side of the framework are covered by sound attenuating or muffling plates 10.Instead of constructing the sides of the frame 4 from separate beams so as to form an open frame, the sides may be formed from suitably reinforced metal sheets, and it falls within the scope of the invention for the frame to be of other cross-sectional shapes, including circular.

Disposed within the frame 4 near its lower end is a guide device 8 consisting of two spaced guides 8a and 8b, each of which is mounted upon a respective lateral side of the frame for pivotal movement between the horizontal position shown in Figure 2, and a lowered substantially vertical position and, possibly, a position raised above that illustrated. Each of the guides comprises a plate 1 5 bearing a pair of hinge eyes 13 pivoted by means of horizontal forwardly extending pins 14 to brackets mounted on one of the beams 4c.

Movement of each of the guides between the two or possibly three positions mentioned above takes place under the action of a ram 24 consisting of a hydraulically operated piston and cylinder unit connected between a lower beam 4c of the same lateral side wall and a point of connection 16 on the underside of the plate 15 of that guide.

Supported on the upper side of each plate 15 is a jaw including an irregularly shaped base plate 1 8a supporting upstanding walls 18 surmounted by a cover plate 1 9 of generally right-angled triangular shape. Guide rollers 20 with right-angled peripheral grooves are supported on pins received in bores in the upstanding walls at the ends of hypotenuse of the cover plate, so that the axis of rotation of each roller is parallel to one of the shorter sides of the cover plate.

The baseplate 1 8a of each jaw is supported for rotation on the plate 1 5 by means of a journal 17 disposed nearer to the rear side of the frame than the point mid-way between the rollers. A portion of the edge of the plate 1 8a is curved around the journal axis and is covered by a holding plate 22 in order to provide additional support. Between the two rollers, an edge surface of the baseplate is formed as a camming surface, for a purpose to be described. As will be appreciated by looking at Figure 2, each jaw may be considered as a two armed lever with a forward roller at the right hand end of the lever (as viewed in Figure 2) and a rearward roller at the left hand end of the lever.

The centre of gravity of each jaw consisting of baseplate 1 8a, upstanding walls 1 8, coverplate 19 and rollers 20 is located between the axis of journal 1 7 and the rear side of the frame 4.

Consequently, when the rams 24 are retracted to cause the guides to adopt vertically depending positions, the jaws turn about their journals and hang with the rearward ones on the rollers 20 lower than the forward ones. Upon extension of the rams 24, the jaws remain in these positions which they have adopted relative to the plates 15, so that when the jaws reach their horizontal positions the forward rollers of the two jaws are further apart from each other than the rearward ones, this spacing of the forward rollers being greater than the width of a pile entering the frame 4 in direction R through the forward side thereof when the doors 11 are open. The jaws when in these relative positions are referred to herein as being "open", whereas in Figure 2 the jaws are shown in their "closed" positions.The eccentric location of the journal 17 facilitates a satisfactory opening of the jaws.

Operation of the pile driving apparatus takes place as follows: The doors 11 are opened and the rams 24 retracted to lower the guides 8a, 8b. A pile lying on the ground is pulled into line with the forward side of the frame 4, and the lower end of the pile introduced into the frame. Displacement of the pile may be effected using the winch 6 and/or other means. With the pile in place or at an earlier stage in the operation, the guides are raised into their horizontal positions whereupon the jaws adopt the open positions, raising of the guides taking place in response to a control signal generated automatically by a main control unit. By reeling in the winch cable, the pile is raised towards the vertical position, swinging about its lower end. Before the vertical position is reached, the pile enters the space between the jaws.

Contact between the pile and the camming surfaces of the edges of the baseplates 1 8a causes the jaws to pivot into the illustrated closed positions and the edges of the pile to be led into the grooves 21 of the rollers. Further reeling-in of the winch cable brings the pile in the truly upright position, guided by the rollers.

At the end of this movement, the monkey 5 is engaged with the upper end of the pile and the pile driving operation is commenced. When the depth of penetration of the pile is such that guidance is unnecessary, the control unit generates a control signal which causes the guides 8a, and 8b to be lowered into their vertically depending positions or, in an alternative mode of operation, to be raised. In either case, the guides are disposed out of the path of movement of the monkey 5 during the final driving stage, in which the monkey can descend to the lower end of the frame 4 and drive the pile fully into the ground. The pile driving apparatus may be provided with a number of sets of guides, the jaws of each of which pertain to a different cross section of pile.The guides may be interchanged very rapidly and easily, simply by extracting the pins 14 to remove one guide, positioning the replacement guide and reinserting the pins.

Alternatively, interchange of the jaws may be carried out by removing the one jaw from the journal 1 7 and introducing a replacement jaw, all of the guides being equipped with uniform positions for the hinge 13 and journal 1 7.

Modifications may of course be made within the scope of the invention. Thus, for example, each of the rollers 20 may be replaced by two or more rollers, and the location of the rollers may be varied to take into account the cross-section of the pile to be driven. Further, movement of the jaws into the open positions need not take place under the effect of gravity. This movement may be carried out by suitably positioned rams or other mechanical means. Finally, displacement of the guides from the path of the monkey may be carried out other than by turning the guides about the hinges, thus for example the guides may be withdrawn while still in the horizintal plane.

Guides in which the jaws turn about axes inclined to the vertical between the open and closed position during insertion of the pile may also be used.

Reference may be made to the disclosure contained in German application No. P29343 10, a copy of which is on the file of this application, to the extent that it contains disclosure beyond the foregoing.

Claims (10)

1. Guide means for piles or other driven members, comprising a frame provided internally with jaws rotatable about axes extending longitudinally of the frame, each jaw being provided with spaced apart guide rollers so arranged that when the pile is in place within the frame, the guide rollers of both jaws encompass the pile such as to restrain it against movement transversely of the frame.

2. Guide means as claimed in claim 1, wherein the jaws are movable out of the vicinity of the pile to permit passage of a device for applying driving force to the pile.

3. Guide means as claimed in claim 1 or claim 2, wherein each jaw is pivoted on a support which is pivoted to the frame about a transverse axis oriented towards a side of the frame through which the pile enters the frame.

4. Guide means as claimed in claim 3, wherein the centre of gravity of each jaw lies between the pivot point of the jaw and that side of the frame opposite the side through which the pile enters.

5. Guide means as claimed in claim 4, wherein the pivot point is disposed eccentrically of the jaw, nearer to said opposite side than the point midway between the rollers.

6. Guide means as claimed in any of claims 3 to 5, including piston and cylinder means for pivoting each support.

7. Guide means as claimed in any preceding claim, wherein each roller has a groove of rightangled profile.

8. Guide means as claimed in any preceding claim, wherein the jaws are replaceable.

9. Guide means for piles or other driven members, comprising an elongate frame open or openable on one side for entry of a pile, a pair of supports pivoted to respective sides of the support adjoining the open side, a jaw pivoted on each support, each jaw bearing two spaced guide rollers, the jaws having a closed position in which the four rollers are disposed at the vertices of a rectangle, and an open position in which the rollers nearer the open side are further apart than the other rollers, the centers of gravity of the jaws being so located relative to their pivots that when the supports are lowered about their pivots, the jaws move into the positions relative to their supports which the jaws occupy when open.

10. Guide means for piles substantially as hereinbefore described with reference to and as illustrated in the drawings.