DE2163933B2 - Device for driving a pile - Google Patents

Description

The invention relates to a device for driving a pile according to the preamble of claim 1.

The well-known diesel pile drivers use a falling piston or steam powered pile drivers work with a very heavy ram that hits a ram plate to hit the in the Transfer soil to be driven pile. Such conventional pile drivers have the disadvantage that they transmit the energy of the falling mass by one blow to a ram plate. Every stroke produces a very loud noisy sound of metal colliding with metal that many people annoyed, even those that are relatively far away from the construction site. The noisy blow is a relatively unsatisfactory one, especially in the case of a steam-operated percussion hammer of the open design Method of power transmission to the stake in order to drive it, because of the sudden, brief nature of this blow. Also work when strong forces are required to drive the pile destroying them on the ramming plate and the pile.

In order to dampen the impact, a number of mechanical ones have already been proposed Coil springs that can also be used in another damping device to use to mitigate the impact of the ram on the mechanical damping device. It is also possible, to form the damping device by an enclosed gas (US-PS 34 46 293).

A similar arrangement to eliminate metal-to-metal impact is known, wherein arranged between the ram and the ram head a compressible body in the loading direction which is designed as an energy store (DE-Gbm 66 02 793).

Such devices save energy for the upward movement of the battering ram, but they are for the upward movement is completely based on mechanical means such as springs or rubber buffers have proven to be unsuitable in the robust operation of a pile driver and that the noise pollution could not eliminate.

On the basis of the known devices, the invention is based on the object, in a ram, in which a metallic impact between the heavy impact piston and the floor pan through a pressure medium cushion is avoided to improve so that

allows easy adaptation to changing field speeds and working conditions will. In addition, the noise when ramming are minimized and overall a more energy-saving and more effective pile driving are made possible.

This object is in the invention Device for ramming a pile solved in that the impact chamber by means of a valve with a Storage chamber communicates with the inlet means;: · for the supply of compressible pressure medium, the valve in its two end positions the connection between the storage chamber and the impact chamber is blocked and can be opened by the lowering percussion piston can be actuated. ■>

Further refinements of the invention emerge from the subclaims.

With the measures of the invention it is achieved that the movement of the piston slows down and its upward movement accelerates. Within the cylinders>: \ DERS padded baffle effect is a strong, padded through a medium shear generated which acts on the cylinder base group down and is transmitted to the pile during the deceleration of the piston with a sudden, medium. Then r. the release of the relaxed pressure medium from the cylinder and a renewed downward movement of the piston as well as a constant repetition takes place. According to the invention, the injected medium is temporarily confined between the piston, which is moving downwards, and the cylinder base assembly, in order to prevent the heavy weight of the piston from hitting the cylinder base assembly. In contrast, the invention makes it possible for the piston, which is slowed in motion, to hit the cylinder base group via a cushion in order to generate an impact, which is followed by a downward thrust which occurs when the piston weight is accelerated upward again.

Other advantages of the invention include 4 » In certain respects, that the pile driver is able to work in four different modes of operation suitable:

1. only double-acting, "

2. single-acting and automatically switching to double-acting at the highest point of the work path,

3. only single-acting and

4. pretensioning plus serving plus pushing.

One of the advantages of the invention is that in the single-acting mode of operation when the rammed When the pile hits softer layers of earth, the working travel of the piston is automatically shortened while the number of surcharges per minute increases. This increases the speed of the quiet, strong impacts and the pile is driven in faster. If, on the other hand, he works on harder layers bumps, the rebound of the piston is automatically higher and results in a longer work path fewer hits per minute, increasing the force of each of the soft, powerful hits by the to overcome any stronger resistance one has encountered.

In the double-acting mode of operation, they increase when one encounters harder layers of soil. Speed and working distance of the piston weight automatically, so that stronger rams take place.

The pressure medium used can be compressed air or steam or any other under pressure standing gas or other pressurized vapors.

The invention is shown in the drawing in some exemplary embodiments and in the following described in more detail. It shows

Fig. 1 is a side elevation of a device for driving a pile on a greatly reduced scale,

Fig.2 is a partially sectioned view of the Device showing the piston in contact with the head of the valve,

F i g. 3 is a partial cross-section along line 4-4 of FIG F i g. 2 as a top view,

4 shows a section through the inlet means for the Print medium,

Fig. 5, 6, 7, 8, 9 and 10 sections similar to Fig. 3. These figures show the successive operating positions of the few moving parts of the Device during an operation to execute a powerful push or push towards the ramming stake.

F i g. 10 the piston in double-acting mode,

F i g. 11 a section along the vertical axis, which shows a modified embodiment of the invention, and

F i g. 12 a section along the vertical axis another embodiment.

Figures 1 and 2 show as an embodiment of the Invention a low-noise device 20 for driving a pile with automatically self-regulating variable travel to work and variable ram impact speed. The device 20 consists from a cylinder wall 22 which surrounds a cylinder 23 which has a heavy percussion piston 24. At the At the lower end of the cylinder wall 22, a floor assembly 26 is arranged, which is the lower end of the cylinder wall 22 closes tightly. The floor pan 26 is coupled to the pile 28 which is to be driven by a releasable coupling 30 and a fitting 32 which is shaped so that it into the upper end of the to ramming post 28 engages

When driving a pile of a different size or shape (such as a tubular pile, H-beam pile, wooden pile) the coupling 30 is temporarily removed and another connection piece 32 to make the desired engagement with the pile. In Figs. 1 and 2, for example a tubular pile 28 is shown.

A baffle chamber 34 (Figure 2) is within the Cylinder wall 22 between the lower end of the heavy impact piston 24 and the cylinder base assembly 26 arranged. For the sudden injection of pressure medium into the impingement chamber 34 under the downwardly moving percussion piston 24, an injection device 36 is provided. The blowing device 36 consists of a storage chamber 38 for the pressure medium and a valve 40, which is connected to the Storage chamber 38 is provided with the impact chamber 34.

The heavy percussion piston 24 moves up and down in the cylinder 23 and strikes a cushion of the Pressure medium in the impingement chamber 34. The operation of the device will be described later.

The percussion piston 24 expediently consists of

a weight 42 of generally cylindrical shape with bearings, piston rings and end caps attached to the lower and upper ends. Its upper and lower ends have the same construction, so that only the lower end in FIG. 2 is shown in detail.

Particular attention is drawn to FIG. 2, from which it can be seen that a bearing sleeve member 44 is attached to each end of the weight 42 . This bearing sleeve portion 44 is annular and fits on a reduced diameter end portion 46 at the end of the weight 42 and rests on an annular projection 48. This bearing sleeve portion 44 is made of a bearing metal and is held by an end cap 50 of tough hardened steel which is attached to the Weight 42 due to detachable fastening center! 52 is attached.

In the illustrated embodiment, the floor pan 26 comprises a second piston 60. This second piston 60 is suitable for up and down movement on a limited working path within a second cylinder 6i, which is delimited by a lower extension of the cylinder wall 22 below the level of the impact chamber 34 In order to hold the piston 60 within the cylinder 61, an annular projection 63 surrounds the piston 60. An annular fastening and bearing part 65 delimits the lower end of the cylinder 61. The fastening and bearing part 65 is fastened with large machine screws 67 to an installation ring 69 which is welded to the outside of the cylinder wall 22. At the lower end of the piston 60 there is a coupling flange 71 which is suitable for the engagement of the releasable coupling 30. The releasable coupling 30 is formed by two semicircular clips with protruding mating collars 73 which are fastened to one another by screws 75.

As an alternative embodiment, FIG. 12 shows that the floor pan 26 can be delimited by a closed lower end of the cylinder 22. In other words, in such an alternative embodiment, the second piston 60 is replaced by a fixed part 604 which is welded or otherwise fastened to the lower part of the cylinder wall 22. so that it forms a whole with the cylinder wall 22.

A floor assembly 26 is preferred here, which comprises a relatively movable second piston 60, because the use of this second piston 60 decouples the cylinder wall 22 from the post 28. This decoupling of the cylinder wall 22 from the pile 28 reduces the mass that must be driven down when the forceful ram thrust occurs in order to drive the pile 28.

As already explained, the medium injection device 36 consists of the storage chamber 38 and the valve 40. The purpose of the injection device 36 is to blow a pressurized medium through an injection opening 62 into the impact chamber 34 under the descending percussion piston 24. The injection of the pressure medium is controlled by the valve 40

The storage chamber 38 is arranged in the second piston 60 of the floor pan 26. The bore 64 of the chamber is lined with a cylinder sleeve 66. A lower flange 68 of an upright valve spindle guide 70 forms the lining of the underside of the storage chamber 38. The valve guide 70 has a bore 72 into which a valve spindle 74 of the valve 76 extends. The valve 76 has a conical surface 78 that rests up against a conical valve seat 80 that is in the end cap 82 of the second piston 60

is trained. This second piston is provided with a bearing sleeve 84, piston rings 86 and an annular stuffing box 88 which has an annular clearance, similar to the parts for the two ends of the percussion piston 24.

To release the valve 40 by the percussion piston 24, an upwardly extending actuator 91 is provided, which is attached to the valve 76. The Betaliger91 is provided with sealing means for the pressure medium in the form of an enlarged cylindrical head 93. This head 93 can be pushed down so that it fits exactly into the opening 62 in order to enclose a pressure medium in the impingement chamber 34.

When the valve member 76 is pressed away from its valve seat 80 downward, print medium can escape from the Storage chamber 38 flow upward through a number of channels 90, around the perimeter of valve member 76 around so that it penetrates through the opening 62 into the impact chamber 34. The channels 90 are through Grooves are formed between the protruding webs 92 in the interior of the cylindrical liner 66.

The print medium is obtained from a suitable source, e.g. B. from the (not shown) storage container an air compressor (not shown). The compressed air has a suitable pressure of for example 5 to 210 bar.

When the valve member 76 is depressed, its annular groove 95 (Fig. 3) acts with the upper end of the Valve guide 70 (as can be seen in FIG. 12) to be opened by trapping the medium in the groove 95 to act as an elastic braking means. This enclosed medium causes elastic braking the movement of the depressed valve part and thus prevents it from suddenly striking down the valve guide 70.

The pressure medium is fed to the pile driving device 20 through a hose pressure line 94 and through a connection piece 96. Via this connection piece 96 it is passed into a bore 98 which is connected to the bore 72 of the valve spindle guide 70. The pressure medium from the bore 72 flows through a narrowed through opening 100 into the chamber 38. When the valve spindle 74 is in its highest position (as shown in FIG. 3), the pressure medium can also enter the chamber through a less narrow opening 102 38 flow in. A parallel flow is present in the two openings 100 and 102; the lower narrow opening 100 is always open, but the upper non-narrowed opening 102 is blocked when the valve part 76 with its spindle 74 is pressed down by the percussion piston 24.

After the percussion piston 24 has bounced upwards from the cushion formed by the pressure medium. as shown in FIG. 9, the relaxed pressure medium 104 emerges from the cylinder 23 through a plurality of outlet openings 106 in the cylinder wall 22 .

Oil is pumped under high pressure via a flap valve into an oil line 180 which leads down to a rotating part 182 (FIG. 8) at the inlet connection piece 96 for the pressure medium. The rotating part 182 has a passage 183 and an annular channel 184 to guide oil inwardly through a pair of openings in the bore 97 of the connecting part 96.

In this way, the lubricating oil is mixed with the incoming pressure medium and thereby it is distributed upward through the bore 98, so that the injection device 36 including the valve 40

is lubricated. This entering through the bore 98 oil is also used to lubricate the Impact chamber 34, of the piston 60 and of the cylinder wall 22 surrounding the piston 60.

In order to allow atmospheric air to flow in and out in the upper part of the cylinder 23 above the percussion piston 24 let is a plurality of air openings 216 (Fig. 1) which are in communication with an annular muffler and air filter housing 140. This Housing defines the inner and outer annular muffler chambers 218 and 220.

In order to allow different types of piling for the pile driving system 20, different sizes of head plug 230 (Fig. 1) is used. The head plugs are at the top of the cylinder wall 22 removable attached. The depth shown in Fig. 1 The head connector 230 extends so far down that it blocks the air openings 216 and thus effects a double-acting ramming method, as will be explained in more detail later is explained. The flat head plug enables a single-acting mode of operation.

When the percussion piston 24 moves extremely far upwards within the cylinder 23, as in FIG. 10 is shown, the single-acting piling method is automatically switched to double-acting operation.

In operation, the pile driving device 20 (Fig. 1) or 20Λ (Fig. 12) can be driven by a cable 236 (Fig. 1) from a suitable crane (not shown) and is attached to suitable mounting means 234 at the upper end of the pile driver, for example on the head plug 230 or 230/4.

It is - as shown in Fig. 11 - the percussion piston 24, when it moves down, in its movement through the pressure medium in the impingement chamber slows down and then pushes it Medium back down into the rammedium storage chamber 38. This can cause the impact take place between the percussion piston 14 and the second piston 60 at a reduced speed. Then the percussion piston 24 starts moving upwards again due to the pressure medium released from the storage chamber 38 via the open valve 40 accelerated.

It will therefore be understood that the embodiment of FIG. 11 works very well for the fourth in the introduction specified operating mode is suitable, namely pre-tensioning plus surcharge plus thrust. The pre-tensioning takes place, while the pressure medium cushion blown into the impingement chamber through the valve 40 together with in The residual medium present in the impact chamber slows down the percussion piston. This bias eliminates that f the entire "play" between the second piston 60 and the post 28. Then, when the percussion piston 24 with impacts the second piston 60, as in FIG F i g. 11, the stake begins with the impact to move downward as indicated by the steps shown in FIG. 11 in The double arrows located near the coupling 30 are indicated A powerful thrust is given to the moving pile so that it continues in a very effective piling process moved downwards This powerful, sustained thrust is exerted on the pile during the percussion piston the upward movement accelerates again

There is an advantageous method of increasing or decreasing the impact in the system MA of FIG. 11. The actuator SiA is lengthened to reduce the impact force and shortened by it zn

enlarge. This lengthening or shortening takes place by removing the valve part 76, at which Place a valve with a longer or shorter actuator 91Λ as required.

When a longer actuator 9iA is used, the valve 40 is opened to inject the pressure medium under the sinking piston 24 when it is further from the floor pan 60. As a result, the pressure medium has a longer exposure time and slows the movement of the percussion piston 24 to a lower speed before the impact occurs, whereby this impact becomes weaker and vice versa.

If a sufficiently long actuator 91Λ is used there is no impact provided that the Rammediumkammer 38 is large enough to hold the impingement chamber with sufficient pressure medium Pressure to fully brake the piston in the time available.

This mode of operation of pre-tensioning plus impact plus shear ramming can be particularly good for very difficult situations to be applied to driven piles. The strength of the impact can be adjusted, as explained above, so that the pile moves Then the post driver applies a powerful, sustained thrust to the moving post effective further ramming. The force of the impact may be just enough to move the post begins which is very effective as the pile is already prestressed. Thus becomes an overly strong Surcharge, as it occurs with the known rams, avoided. The strong, sustained replenishment is very effective because it is already one moving stake.

Fig. 12 shows another modified pile driving device 20SaIs embodiment of the invention, the The only change compared to the pile driving system is suitable for carrying out the procedure and method 20 is that in the system 20 ß the floor pan 60Λ is attached to the lower end of the cylinder wall 22. This floor pan is through a large number of machine screws 262 attached. This attachment is advantageous because it increases the number of moving parts in the pile driver is reduced to two, namely the percussion piston 24 and the valve part 76. (When calculating two moving parts, the lubrication system 150,160 is not included because that Lubrication system is shown as an advantageous feature of the illustrated embodiment. It could however, other conventional lubrication systems can be used).

The pile driving devices 20 or 20A, the three moving parts 24, 60 and 76 are currently preferred include, since the movement of the floor pan 60 the effective mass to be rammed by the uncoupling Mass of the cylinder wall 22 (together with everything that is rigidly attached to the wall 22) from the to reducing the pile driving and thus facilitating the pile driving accordingly. However, with some Pile driving applications have the advantage of having fewer moving parts than the advantage of having To effectively reduce rammed mass, take precedence.

If the pile driving systems are 20.20A or 20J? done are set up to drive a stake, the Up and down movement of the heavy percussion piston 24 is initiated as follows: Initially, the piston rests firmly of the floor pan 26,60,6OA Thus, the valve actuator 91 or 91Λ is pressed down, so that the valve 76

10

15th

20th

away from his seat. There is a slight play around the enlarged head 93, so that compressed air can penetrate from the storage chamber 38 into the impact chamber 34. There is a large amount of play around the actuator 91A so that the air can flow from the storage chamber 38 into the impingement chamber 34.

The operator of the pile drivers 20, 20A or 20S starts them by suddenly opening a shut-off valve (not shown) in order to supply the pressure medium through the hose line 94. The storage chamber 38 is then supplied with pressure medium through the narrow opening 100 (FIG. 2). (The large opening 102 is now blocked by the firmly pressed down spindle 74).

In the device 20 or 203, the pressure medium trills into the impingement chamber 34 by seeping in through the play around the head 93. The percussion piston 24 is lifted by the entering medium, and the pressure medium in the bore 72 acts on the spindle 74, so that the valve part 76 rises together with the percussion piston 24 upwards. When the head 93 emerges from the injection port 62, the pressure medium accumulated in the storage chamber 38 pushes upwards into the impingement chamber 34 to suddenly push the piston upwards. The valve part 76 rises against its seat 80 and closes the valve 40. The opening 102 is released because the spindle 74 has moved upwards. The pressure medium now flows through openings 100 and 102, so that the pressure in the storage chamber 38 now has increased substantially to the supply pressure.

In the pile-driving apparatus 20/4 of FIG. 11 on the operator the percussion piston 24 in the same manner a as in the devices 20 and 20SS, namely by sudden switching of the flow of the pressure medium through the opening 100, the pressure medium can through the conduit 94. in the storage chamber 38 rise, and it flows through the opened valve 40 upwards. This upward flow of the pressure medium through the opened valve 40 suddenly pushes the percussion piston 24 upwards.

The upward shock suddenly acting on the percussion piston 24 in the devices 20, 20A or 20ß lifts it, as in FIG. 9 to the point where the exit ports 106 are exposed. The relaxed pressure medium in the impingement chamber 34

40 exits through the openings 106 , as a result of which the percussion piston falls down, as shown in FIG. 5. When the percussion piston strikes the actuator 91 (FIG. 6), the valve 40 suddenly opens in order to blow pressure medium from the storage chamber 38 into the impingement chamber 34. This second injection of pressure medium is greater than the first because the pressure in the storage chamber 38 has approached the supply pressure more closely. Thus, the movement of the percussion piston 27 is accelerated more and rises, as in FIG. 9 further beyond the outlet openings 106 .

The relaxed medium exits into the atmosphere and the percussion piston falls down again (Fig. 5). It falls faster than the first time and it opens the valve, as shown in FIG. 6 can be seen, this being May the valve opens wider and longer than the first time because the percussion piston sinks further down. Correspondingly, even more pressure medium is blown in in order to throw the percussion piston even higher than the second time, and so on. After about 3–6 work steps, the percussion piston 24 reaches its full potential Work travel length for pile driving. As the F i g. 5, 6, 7, 8, 9 and 10 show the percussion piston sinks when its full travel length is reached, so far down in each work cycle that the head 93 goes so far is lowered so that it blocks the opening 62, as shown in FIG.

In all of the devices shown, the up and down movement of the percussion piston 24 is controlled by the Shutting off the pressure medium flow through the hose line 94 stopped.

The operator can advantageously extend the duration of each medium-padded powerful ramming impact and can reduce the maximum force that occurs with each impact by increasing the through the containment means 93 (Fig. 2) included amount of print medium, and vice versa, by enlargement the height of the head 93, the opening 62 is blocked when the percussion piston 24 is in a larger a predetermined distance from the floor pan 26, whereby the trapped amount increases and vice versa, if desired, removable and interchangeable heads 93 which are fastened to the actuator 91 by screws.

In addition 6 sheets of drawings

Claims (10)

Patent claims: 1. Device for driving a pile with a cylinder and one in the cylinder axially various heavy percussion pistons, with one that seals the cylinder at the bottom Floor pan, with the bottom of the percussion piston, the cylinder wall and the top of the Floor pan delimit an impact chamber, and with ι υ outlet openings for relaxed pressure medium, which are provided at a distance above the floor pan in the cylinder wall, characterized in that that the impact chamber (34) by means of a valve (40) with a storage chamber (38) in ι> Connection stands, the inlet means (94,96,98) for the Having feed of compressible pressure medium, the valve (40) in both of its End positions the connection of the storage chamber g8) with the impact chamber (34) blocked and to The opening can be actuated by the lowering impact piston (24) 2. Device according to claim 1, characterized in that that the bottom group (26), the storage chamber (38) for the compressible pressure medium 2> includes. 3. Apparatus according to claim 1, characterized in that the valve (40) has a head (93) for Blocking the connection of the storage chamber (38) with the impingement chamber (34). «> 4. Apparatus according to claim 1, characterized in that the floor pan (26) with respect to the The cylinder wall (22) comprises axially displaceable piston (60) which can be coupled to the post (28) in such a way that Shear effects are transferable. ή 5. Apparatus according to claim 4, characterized in that the piston (60) has both bores (98) for the passage of the pressure medium, as well as the storage chamber fed through these bores (38) and the valve (40), which is opened 4 "to the pressure medium from the storage chamber (38) to enter the impact chamber (34) when the heavy percussion piston (24) is the Sew the piston (60). 6. Apparatus according to claim 5, characterized in that by means of the head (93) the pressure medium (C, C), after it has flowed from the storage chamber (38) into the impingement chamber (34), can be enclosed in the impingement chamber (34) . 7. Apparatus according to claim 6, characterized in that the piston (60) has an opening (62) which establishes the connection between the storage chamber (38) and the impact chamber (34), wherein the head (93) of the valve (40) can be pressed into this opening (62) in order to close it. 8. Apparatus according to claim 6, characterized in that the valve (40) comprises a valve part (76) which can be pressed down with the actuating means (91, 9iA) , the storage chamber (38) and the valve part (76) thus fitting into one another Parts (70,95) have that there is a pressure medium cushion between them. 9. Device according to one of claims 1 to 5, characterized in that the storage chamber (38) a valve guide (70) with a cylinder f> 5 wall (22) has a coaxial bore (72) into which a spindle (74) of the valve part (76) extends and which is in communication with the bores (98) for the pressure medium, wherein the valve guide (70) with an opening serving to connect the bore (72) and the storage chamber (38) (10 <!) and that the valve part (76) in its upper and lower end position the opening (62) blocked, as well as the opening in intermediate positions (62) released 10. The device according to claim 9, characterized in that the valve guide (70) has a has upper and lower openings (102, 100), each of which is the connection between the bore (72) and the storage chamber (38), the upper opening (102) being larger than the lower and the spindle (74) of the valve (40) blocks the upper opening (102) when the valve (40) moves downwards will.