GB2258627A

GB2258627A - Pile cutters

Info

Publication number: GB2258627A
Application number: GB9215411A
Authority: GB
Inventors: Roger Alfred Bullivant
Original assignee: Roxbury Ltd
Current assignee: Roxbury Ltd
Priority date: 1991-08-16
Filing date: 1992-07-21
Publication date: 1993-02-17
Anticipated expiration: 2012-07-21
Also published as: GB2258627B; GB9215411D0

Abstract

A pile cutter (10) for cutting a concrete pile (100) comprises cutting means (12), force applying means (16) to apply a first force to the cutting means (12), and reaction means (18) arranged opposite the cutting means (12), The pile (100) can be received between the cutting means (12) and the reaction means (14) such that the reaction means (14) is adapted to apply a second force in reaction to the first force. <IMAGE>

Description

IMPROVEMENTS IN OR RELATING TO PILE CUTTERS This invention relates to pile cutters.

In the building and allied industries pre-cast concrete piles reinforced with steel rods are often used.

When such a pile is driven into the ground, its top portion can protrude above the ground level. In such cases, it is necessary to remove the top portion by cutting it off. This is presently accomplished by the use of sledge hammers to shatter the concrete and suitable cutting means to cut the reinforcement. Also, in some cases, it is nessesary to cut the pile at a point just below the ground level and here it is necessary first of all to dig around the pile initially to expose the pile at the level at which it is to be cut.

The use of sledge hammers is unsatisfactory since it can result in the concrete cracking in that portion of the pile which it is desired to retain. Also the use of sledge hammers does not result in a clean break.

It is an object of the present invention to obviate or mitigate these and other disadvantages.

According to the present invention, there is provided a pile cutter for cutting a concrete pile, the cutter comprising cutting means, force applying means to apply a first force to the cutting means, and reaction means arranged opposite the cutting means whereby the pile can be received between the cutting means and the reaction means, the reaction means being adapted to apply a second force in reaction to the first force.

The pile cutter may comprise a support means to support the force applying means. Preferably, the support means comprises a frame upon which the force applying means is mounted. Preferably, the frame is shaped so as to be capable of being disposed over the pile. The reaction means may be mounted on the support means.

The pile cutter may include transmission means to transmit the first force from the force applying means to the cutting means.

The transmission means may comprise an elongate member having first and second end portions pivotally mounted on the support means at the first end portion.

The cutting means is preferably provided on the second end portion, and the force applying means is preferably arranged so that the first force is applied to the transmission means at the second end portion to cause the transmission means to pivot thereby to move the cutting means in the first direction.

In a first embodiment, the reaction means is fixedly mounted to the support means. Guide means may be provided to guide the force applying means to ensure that the first force is applied to be transmitted. Preferably, the guide means comprises a rod pivotally mounted at one end thereof to the support means and attached at its other end to the force applying means.

In a second embodiment, the transmission means comprises an elongate member having a first end portion and a second end portion angled about a middle portion to form a bell crank. Preferably the tranmission means may be pivotally attached to the support means at the middle portion.

In the second embodiment, the force applying means applies the first force to the transmission means at the first end portion, the cutting means being provided on the second end portion. Preferably, the second end portion is arranged below the middle portion. This has the advantge that the pile cutter can be used to cut the pile at a region below the surface of the ground.

In the second embodiment, the reaction means is provided on an arm rigidly fixed to and extending below the support means.

In a third embodiment, the transmission means comprises a carrier connected to the force applying means for movement thereby, said carrier carrying a carrying member, and said transmission means further including an elongate member having first and second end portions, and a carrying surface for engagement with the carrying member, the elongate member being pivotally mounted on the support means at said first end portion. Preferably, the cutting means is provided at the second end portion of the elongate member. Movement of the carrier by the force applying means moves the carrying member therewith along the carrying surface to transmit said first force to the cutting means.

The carrier may comprise an outer member arranged around the support means and the elongate member.

The force applying means may comprise an hydraulic cylinder. Preferably, the cutting means comprises a first elongate cutting edge.

Alternatively, the cutting means may have first and second elongate cutting edges arranged opposite each other. The cutting means may have a mounting point arranged closer to the first edge than the second edge whereby the cutting member can be selectively mounted on the elongate member with said first or said second cutting edges in a cutting position for cutting the pile. This second cutting edge protrudes further than the first cutting edge when the first and second cutting edges are respectively in the cutting position.

An embodiment of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which Fig. 1 is a side view of a first embodiment of the invention; Fig. 2 is a sectional plan viewed on the lines II-II in Fig. 1; Fig. 3 is a side view of a second embodiment of the invention; Fig. 4 is a schematic view of a cutting means; Fig. 5 is a front view of a third embodiment of the invention; and Fig. 6 is a view along the lines VI-VI of Fig. 5.

Referring to the drawings, Figs. 1 and 2 show a first embodiment of the invention which is used to cut piles at ground level. The pile cutter is generally designated 10 and comprises cutting means 12 in the form of a first elongate blade having a first elongate cutting edge 14. The pile cutter 10 also comprises force applying means in the form of an hydraulic ram 16 to apply a first force to the cutting means 12, to move the cutting means 12 in a first direction as indicated by the arrow A.

The pile cutter 10 also comprises support means 22 in the form of a frame fabricated from sheet steel upon which the various components are mounted.

The pile cutter 10 comprises also reaction means 18 in the form of a second elongate blade having a second elongate cutting edge 20 fixedly mounted on the support means 22 and adapted to provide a second force in reaction to the first force in the direction opposite to that indicated by the arrow A.

Transmission means 24 comprise an elongate member pivotally mounted at one end thereof to the support means 22 at pivot 26 and transmit the first force from the hydraulic ram 16 to the first blade 12. The first blade 12 is attached to the transmission means 24 at the end remote from the pivot 26 as shown in Fig. 1.

A rod 28 is pivotally mounted at one of its end at pivot 29 to the support means 22 and its other end is attached to the hydraulic ram 16 by means of a shaft 30.

Thus, the first force applied by the hydraulic ram 16 causes the rod 28 to rotate in the direction indicated by arrow B against the elongate member 24 which rotates towards the pile to be cut.

In operation, the pile cutter is lowered over the pile to be cut (generally designated 100). As can be seen from Fig. 1, the pile 100 is received between the cutting means 12 and the reaction means 18. When the pile cutter 10 is in position, the hydraulic ram 16 is activated to apply the first force. The hydraulic ram 16 can conveniently be connected to the circuitry of appropriate machinery used on building sites, for example an excavator.

The first force from the hydraulic ram 16 is applied via the rod 28 to the transmission means 24, to transmit the first force to the cuttings means 12. The transmission means 24 has a surface 32 over which the rod 28 can slide. Thus, the surface 32 acts as a cam surface.

When the first force is applied by the hydraulic cylinder 16, the cutting means 12 is forced into the pile 100 to cut it. As the first force is applied the reaction means 18 which is in engagement with the pile applies a reaction force in the opposite direction to the first force. It will be appreciated, that the cutting means 12 and the reaction means 18 form a system of equal and opposite forces to fracture the concrete of the pile and produce a clean break across the pile.

This embodiment has the advantage that the distance travelled by the cutting means to cut the pile is very small and so there is a very high mechanical advantage.

This results in low hydraulic pressure being required to operate the hydraulic cylinder 16.

As can be seen from Fig. 2, the pile cutter 10 comprises a pair of transmission means 24 and rods 28, each being mounted on opposite sides of the support means 22 as shown.

Fig. 3 shows another embodiment of the invention which is used for cutting piles below the ground. In this figure, many of the features are the same as those shown in Figs. 1 and 2. These features have been designated by the same reference numerals as those of Figs. 1 and 2.

The transmission means 24 is in this embodiment has a ball-crank configuration as shown in Fig. 3. The transmission means 24 is pivotally mounted at the middle portion 42 thereof to the support means 22 by pivot 44.

The cutting means 12 is mounted at one end of the transmission means 24. The other end of the transmission means 24 is connected to the hydraulic ram 16 by a shaft 46. Thus when the hydraulic ram 16 applies the first force the transmission means 24 rotates in the direction of arrow B to move the cutting means in the direction of arrow A to cut the pile 100.

The reaction means 18 is mounted at one end of an arm 48. The opposite end of the arm 48 is fixedly attached to the support means by pins 50.

The arm 48 is also fixedly attached to the support means 22 at a middle portion 52 of the arm 48 by a pin 54.

Thus, the second embodiment of the invention provides a pile cutter which enables clean breaks to be made of piles below the surface of the ground.

Figs. 5 and 6 show a third embodiment of the invention. In this figure, many of the features are the same as those shown in Figs, 1 and 2.

In the third embodiment shown in Figs. 5 and 6 the transmission means 24 comprises an outer member 60, a camming member 62 mounted on the outer member 60, and an elongate member 24 mounted on the support means 22. The elongate member 24 is pivotally mounted on the support means 22 at pivot 66 at one end there of and the cutting means 14 is provided at the opposite end of the elongate member 24. The camming member 62 comprises a plurality of camming wheels 64. In the embodiment shown, the camming member 62 has three camming wheel 64. The elongate member 24 is provided with a camming surface 68 adapted to engage each of the camming wheels 64 of the camming member 62.

The purpose of this arrangement will be explained below.

Force applying means in the form of first and second hydraulic rams 16 are attached to the support means 22 (see Fig. 6). The hydraulic rams 16 are also connected to the outer member 60. Actuation of the hydraulic rams 16 to apply a force downwardly to the outer member 60 causes the camming member 60 to move downwardly against the camming surface 68 thereby driving the cutting means 12 into the pile. The pile 100 is thereby cut by the repetitive action of the hydraulic rams 16 applying the force downwardly to the outer member 60.

Fig. 4 shows a modification of the cutting means 12 in which two elongate blades 14a and 14b are provided.

The cutting means 12 has an off set bore 70 and is fixed to the transmission means 24 by means about a shaft (not shown) passing through the bore 70. It will therefore be appreciated that by rotating the cutting means about the shaft blade 14b can be used instead of the blade 14a, This has the advantage that narrower piles can be cut by the same apparatus simply by changing the position of the cutting means.

Various modifications can be made without departing from the invention. For example, in the first embodiment, the rod 28 could be omitted and the hydraulic cylinder 16 connected directly to the transmission means 24. Also it is not essential for the transmission means to be connected to the frame as shown in Fig. 1 and could be connected at any other suitable position. The hydraulic cylinder 16 could be replaced by a screw-jack or other suitable means to apply the first force.

Claims

Claims:

1. A pile cutter for cutting a concrete pile, the cutter comprising cutting means, force applying means to apply a first force to the cutting means, and reaction means arranged opposite the cutting means whereby the pile can be received between the cutting means and the reaction means, the reaction means being adapted to apply a second force in reaction to the first force.

2. A pile cutter according to claim 1, including transmission means to transmit the first force from the force applying means to the cutting means.

3. A pile cutter according to claim 2, including a support means to support the force applying means, the support means comprises a frame upon which the force applying means is mounted, and the frame being shaped so as to be capable of being disposed over the pile.

4. A pile cutter according to claim 3, wherein the reaction means is mounted on the support means.

5. A pile cutter according to claim 3 or 4, wherein the transmission means includes an elongate member having first and second end portions pivotally mounted on the support means at the first end portion, the cutting means being provided on the second end portion, and the force applying means being arranged so that the force is applied to the transmission means at the second end portion to cause the transmission means to pivot thereby to move the cutting means in the first direction.

6. A pile cutter according to any of claims 2 to 5, wherein the reaction means is fixedly mounted to the support means, and guide means are provided to guide the force applying means to ensure that the first force is applied to the transmission means to be transmitted.

7. A pile cutter according to claim 6, wherein the guide means comprises a rod pivotally mounted at one end thereof to the support means and attached at its other end to the force applying means.

8. A pile cutter according to any of claims 2 to 4, wherein the transmission means comprises an elongate member having a first end portion and a second end portion angled about a middle portion to form a bell crank, the transmission means being pivotally attached to the support means at the middle portion.

9. A pile cutter according to claim 8, wherein the reaction means is provided on an arm rigidly fixed to and extending below the support means.

10. A pile cutter according to claim 2,3 or 4, wherein the transmission means comprises a carrier connected to the force applying means for movement thereby, said carrier carrying a camming member, and said transmission means further including an elongate member having first and second end portions, and a camming surface for engagement with the camming member, the elongate member being pivotally mounted on the support means at said first end portion, the cutting means, being provided at the second end portion of the elongate member, and the carrier being so connected to the force applying means that movement of the carrier by the force applying means moves the camming member along said camming surface to transmit said first force to the cutting means.

11. A pile cutter according to claim 1, wherein the carrier comprises an outer member arranged around the support means and the elongate member.

12. A pile cutter according to any preceding claim, wherein the force applying means comprises an hydraulic ram

13. A pile cutter according to any preceding claim, wherein the cutting means has an elongate cutting edge adapted to extend across the pile.

14. A pile cutter according to claim 13, wherein the cutting means comprises first and second elongate cutting edges arranged opposite each other, the cutting means having a mounting point arranged closer to the first edge than the second edge.

15. A pile cutter substantially as herein described with reference to and as shown in the accompanying drawings.

16. Any novel subject matter or combination including novel subject matter disclosed in the foregoing specification or claims and/or shown in the drawings, whether or not within the scope of or relating to the same invention as any of the preceding claims.