US20150275458A1 - Pile hammer - Google Patents
Pile hammer Download PDFInfo
- Publication number
- US20150275458A1 US20150275458A1 US14/663,549 US201514663549A US2015275458A1 US 20150275458 A1 US20150275458 A1 US 20150275458A1 US 201514663549 A US201514663549 A US 201514663549A US 2015275458 A1 US2015275458 A1 US 2015275458A1
- Authority
- US
- United States
- Prior art keywords
- piston
- pile hammer
- cylinder
- striker
- hammer according
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D7/00—Methods or apparatus for placing sheet pile bulkheads, piles, mouldpipes, or other moulds
- E02D7/02—Placing by driving
- E02D7/06—Power-driven drivers
- E02D7/12—Drivers with explosion chambers
- E02D7/125—Diesel drivers
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Placing Or Removing Of Piles Or Sheet Piles, Or Accessories Thereof (AREA)
Abstract
A pile hammer includes a cylinder, a piston displaceably guided in the cylinder, and a striker displaceably guided in the cylinder. The striker is disposed underneath the piston in the operating position of the pile hammer. A combustion chamber is delimited axially by a face surface of the striker that lies in the interior of the cylinder and by a face surface of the piston. Using at least one fuel feed device a predetermined amount of fuel can be introduced into the combustion chamber during each work cycle. The piston has a cavity that is filled, at least in part, with a movable filler.
Description
- Applicant claims priority under 35 U.S.C. §119 of European Application No. 14162394.2 filed Mar. 28, 2014, the disclosure of which is incorporated by reference.
- 1. Field of the Invention
- The invention relates to a pile hammer comprising a cylinder, a piston displaceably guided in the cylinder, and a striker displaceably guided in the cylinder.
- 2. Description of the Related Art
- With pile-driving concrete pillars, the problem regularly exists that the low maximally permissible pressure and tension stresses in the pillar require special measures to prevent damage to the concrete pillars. For this purpose, a damping package is disposed between the workpiece of the pile-driver and the pillar, in order to counteract damage to the concrete pillar.
- It is a disadvantage of the known arrangement that a damping package must be affixed before pile-driving every concrete pillar, thereby increasing the effort and expenditure.
- The invention wishes to provide a remedy for this situation. The invention is based on the task of making available a pile hammer that allows pile-driving concrete pillars, without the requirement of an additional damping package. According to the invention, this task is accomplished by means of a pile hammer including a cylinder, a piston displaceably guided in the cylinder, and a striker displaceably guided in the cylinder. The striker is disposed underneath the piston in the operating position of the pile hammer. A combustion chamber is delimited axially by a face surface of the striker that lies in the interior of the cylinder and by a face surface of the piston. Using at least one fuel feed device, a predetermined amount of fuel can be introduced into the combustion chamber. The piston has a cavity that is filled, at least in part, with a second filler that is different from the piston material.
- With the invention, a pile hammer is made available that allows pile-driving concrete pillars, without the requirement of an additional damping package. By configuring the piston to have a cavity that is filled at least in part with a movable filler, damping of the impact is achieved. As a result, damage to the concrete pillar is counteracted without the requirement of an additional damping package.
- In a further development of the invention, the cavity of the piston is closed off by way of a lid releasably connected with the piston. In this way, the introduction of different fillers is made possible, in contrast to non-releasable attachment—which is also possible—by means of welding, for example, thereby making it possible to adjust different damping, depending on the material of the pillar to be pile-driven. Preferably, the filler is formed by a bulk material or a liquid. In particular, quartz sand or also metal blasting media, particularly steel or aluminum blasting media, are used here as bulk materials. Suitable liquids are oil or water, for example.
- In a further development of the invention, the filler is formed from particles having an essentially round geometry. In this way, a low settling time of the material is achieved, thereby bringing about an optimal damping progression.
- In a further embodiment of the invention, a projection for engagement of a disengagement device is disposed on the piston at its end opposite the combustion chamber. In this way, the lifting groove of the cylinder can be eliminated, because the lifting procedure takes place entirely outside of the cylinder.
- In a further embodiment of the invention, an encapsulation hood is provided, which can be set onto a concrete pillar and has an opening for the striker to pass through. Alternatively, the encapsulation hood can also be configured so that it can be attached to the cylinder of the pile hammer. In this way, sound-absorbing mantling of the impact surface is brought about, thereby bringing about a reduction in the noise emissions. Because the impact of the striker on the pillar represents a main sound source, a significant reduction in the noise level during the pile-driving process is thereby brought about. It is advantageous to dispose at least one sound-absorption element on the encapsulation hood, surrounding the passage opening. More or less homogeneous or fibrous materials are particularly suitable as sound-absorption elements, the thickness of which is defined through the lower frequency at which almost complete absorption of the impacting sound waves can still be achieved. A corresponding absorption can also be achieved by means of the placement of a suitable flow resistance, for example in the form of a nonwoven fiber fabric, which is stretched onto a perforated metal sheet having a perforation in the form of holes or slits, for example, which perforation is sufficiently large and distributed as uniformly as possible.
- Other objects and features of the invention will become apparent from the following detailed description considered in connection with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the invention.
- In the drawings, wherein similar reference characters denote similar elements throughout the several views:
-
FIG. 1 is a schematic representation of a pile hammer in the form of a diesel pile driver; -
FIG. 2 is a representation of the piston of the pile hammer fromFIG. 1 ; -
FIG. 3 is a schematic representation of the placement of an encapsulation hood between pile hammer and concrete pillar; and -
FIG. 4 is a schematic representation of the upper segment of the pile hammer fromFIG. 1 , with the disengagement apparatus disposed on it. - Referring now in detail to the drawings, the pile hammer shown in
FIG. 1 selected as an exemplary embodiment comprises a cylinder 1 that is open on both sides, and regularly can have a length of 3 to 8 meters and a diameter of 0.2 to 1.5 meters. Apiston 2 is displaceably disposed in the cylinder 1. Astriker 3 coaxial to thepiston 2 engages into the open lower end of the cylinder 1, in displaceable manner. A ring-shaped bearing unit 9 is attached at the lower end of the cylinder 1, in which unit acentral shaft section 31 of thestriker 3 is guided in tight and displaceable manner.Central shaft section 31 has an outside diameter that is reduced as compared with the inside diameter of the cylinder 1. The pile hammer is mounted so as to be vertically displaceable along a leader, by way ofguide jaws 13 disposed on the cylinder 1. - A
striker plate 32 that lies below the cylinder 1 is formed onto the lower end of theshaft section 31, the lowerconvex delimitation surface 33 of which plate, directed outward, interacts with the upper end of aconcrete pillar 8 shown inFIG. 3 to be pile-driven during operation. - A
piston section 34 having multiple circumferential sealing rings, spaced apart from one another axially, which run on theinner mantle surface 11 of the cylinder 1, is formed onto the upper end of theshaft section 31 of thestriker 3. Acombustion chamber 12 is delimited by the top of thepiston section 34 of thestriker 3, together with the underside of thepiston 2 as well as theinner mantle surface 11 of the cylinder 1. The face surface of thestriker 3 that faces thecombustion chamber 12 of the cylinder 1 is ground to be planar with aflat fuel bowl 30. - A
damping ring 91 is disposed between thestriker plate 32 of thestriker 3 and thebearing unit 9 of the cylinder 1. Afurther damping ring 92 is disposed adjacent to thebearing unit 9, between the top of thebearing unit 9 and the underside of thepiston section 34 of thestriker 3. - A lower working
end 23 of thepiston 2, provided withcircumferential sealing rings 93 spaced apart from one another axially, runs in the interior of the cylinder 1, above thestriker 3. The lowerfree face surface 21 of thepiston 2, which is ground to be planar, is set off by means of a radially circumferential step. - A
mass section 22 that extends into the upper section of the cylinder 1 and has a cavity 24 (FIG. 2 ) on the inside is formed onto the lower workingend 23 of thepiston 2. Thecavity 24 is closed off with alid 25 shown inFIGS. 2 and 4 on its end of thepiston 2 that lies opposite theface surface 21. In the exemplary embodiment, thelid 25 is attached to thepiston 2 by way ofscrews 251. Thelid 25 is provided with a threadedbore 252 in its center. The threaded bore 252 serves for engagement of a screw anchor—not shown—for handling of thelid 25. Aprojection 26 is formed onto thepiston 2 on the end side, running circumferentially on the outside, in the region of thelid 25. Theprojection 26 serves for accommodating thehooks 71 of adisengagement apparatus 7. In the exemplary embodiment, thecavity 24 of thepiston 2 is filled with quartz sand. - An
injection apparatus 4 is disposed on the circumference wall of the cylinder 1, which apparatus comprises afuel pump 41 that is connected with theinjection nozzle 42 by way of aline 43. The inlet of thefuel pump 41 is supplied with diesel oil by way of afuel tank 5. - The
fuel pump 41, connected with thefuel tank 5 by way of theline 43, has a biasedpump lever 44 that projects into the interior of the cylinder 1, by way of which lever the pump is driven as thedropping piston 2 moves past it. Theinjection nozzle 42 is configured and oriented in such a manner that the fuel emitted is sprayed approximately onto the center of the face surface of thestriker 3 in an essentially cohesive stream. - Furthermore, a
lubricant dispenser 51 is disposed on the cylinder 1, which dispenser is connected with lubricant nozzles distributed in the circumference direction of the cylinder 1. The lubricant is dispensed between thepiston 2 and theinner mantle surface 11 of the cylinder 1 by means of the lubricant nozzles. - In
FIG. 3 , use of the pile hammer with anencapsulation hood 6 is shown. Theencapsulation hood 6 is configured essentially as a hollow cylinder and has a ring-shapedsound absorption element 61 on its end facing the pile hammer, which element delimits thepassage opening 62. Below thesound absorption element 61, apillar accommodation 63 is disposed in theencapsulation hood 6, which accommodation is provided with anelastomer layer 64 on its side facing thepillar 8. Theencapsulation hood 6 serves to reduce the sound emissions during impact of thestriker 3. - The pile hammer described above works as follows: In the starting state, the
piston 2 is raised into an upper position by way of adisengagement apparatus 7. For this purpose, thehook 71 of thedisengagement apparatus 7 engages into theprojection 26 of thepiston 2 and thepiston 2 is subsequently pulled upward by way of thehook 71, which hook is connected with acable winch 72 for this purpose. After disengagement of thehook 71, thepiston 2 falls downward under the effect of gravity, closes the workingconnectors 16, and activates thepump lever 44 of theinjection apparatus 4 with itsface surface 21, thereby causing theinjection nozzle 42 to spray fuel onto thefuel bowl 30 of thestriker 3. Here, an ignitable mixture of fuel droplets and air is formed by means of impact atomization. - When the
piston 2 impacts thestriker 3, a force directed downward is exerted by thestriker 3, and, by way of thestriker 3, on theconcrete pillar 8, which force drives theconcrete pillar 8 further into the ground. Because of the quartz sand introduced into thecavity 24 of thepiston 2, the impulse of the piston is damped, thereby counteracting damage to the concrete pillar during impact. In this connection, the sound emitted during impact of thepiston 2 on thestriker 3, and, by way of thestriker 3, onto theconcrete pillar 8, is reduced by means of theencapsulation hood 6. - During the subsequent upward movement of the
piston 2, triggered by the explosion-like combustion of the fuel, thepiston 2 releases the workingconnectors 16 again, thereby causing the combustion gases to relax and to flow away by way of the workingconnectors 16. Thepiston 2 is now accelerated further upward, drawing fresh air in through the workingconnectors 16, until it has reached its upper end position and the work cycle, as described, is repeated. - Although only a few embodiments of the present invention have been shown and described, it is to be understood that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention.
Claims (11)
1. A pile hammer comprising:
(a) a cylinder having an interior;
(b) a piston displaceably guided in the cylinder and having a piston face surface, said piston being formed by a piston material;
(c) a striker displaceably guided in the cylinder and disposed underneath the piston in an operating position, said striker having a striker face surface lying in the interior of the cylinder;
(d) a combustion chamber delimited axially by the striker face surface and by the piston face surface; and
(e) at least one fuel feed device for introduction of a predetermined amount of fuel into the combustion chamber;
wherein the piston has a cavity that is filled at least in part with a filler material different from the piston material
2. The pile hammer according to claim 1 , wherein the filler is disposed within the cavity in movable manner.
3. The pile hammer according to claim 1 , wherein the cavity of the piston is closed off with a lid that is releasably connected with the piston.
4. The pile hammer according to claim 1 , wherein the filler is formed from at least one of a bulk material and a liquid.
5. The pile hammer according to claim 4 , wherein the filler contains at least one of quartz sand and metal blasting medium.
6. The pile hammer according to claim 5 , wherein the metal blasting medium is a steel blasting medium, a lead blasting medium, or an aluminum blasting medium.
7. The pile hammer according to claim 5 , wherein the filler is formed by particles having an essentially round geometry.
8. The pile hammer according to claim 4 , wherein the filler is formed by at least one of water and oil.
9. The pile hammer according to claim 1 , further comprising a projection for engagement of a disengagement apparatus, wherein the projection is disposed on the piston, on an end of the piston lying opposite the combustion chamber.
10. The pile hammer according to claim 1 , further comprising an encapsulation hood for placement onto a concrete pillar, wherein the encapsulation hood has a passage for the striker to pass through.
11. The pile hammer according to claim 10 , wherein at least one sound absorption element is disposed in the encapsulation hood, surrounding the passage opening.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP14162394.2A EP2924171B1 (en) | 2014-03-28 | 2014-03-28 | Pile driving hammer |
EP14162394.2 | 2014-03-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
US20150275458A1 true US20150275458A1 (en) | 2015-10-01 |
Family
ID=50389326
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/663,549 Abandoned US20150275458A1 (en) | 2014-03-28 | 2015-03-20 | Pile hammer |
Country Status (3)
Country | Link |
---|---|
US (1) | US20150275458A1 (en) |
EP (1) | EP2924171B1 (en) |
CN (1) | CN104947667A (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105274990B (en) * | 2015-11-17 | 2017-08-22 | 上海工程机械厂有限公司 | A kind of circulating water cooling system of diesel hammer |
Citations (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US886193A (en) * | 1907-11-12 | 1908-04-28 | Frank L Aymond | Compressed-air-cushion block. |
US2633832A (en) * | 1949-07-22 | 1953-04-07 | Syntron Co | Diesel hammer |
US2723532A (en) * | 1955-11-15 | Pile driving cap block | ||
US3130762A (en) * | 1961-06-21 | 1964-04-28 | Henry K Kerr | Hammer with detachable striking head faces |
US3721095A (en) * | 1971-08-23 | 1973-03-20 | Bolt Associates Inc | Controllable force method and system of driving piles |
US3788402A (en) * | 1970-12-29 | 1974-01-29 | Bolt Associates Inc | Automatically self-regulating variable-stroke, variable-rate and quiet-operating pile driver apparatus |
US3797585A (en) * | 1971-10-18 | 1974-03-19 | B Ludvigson | Apparatus for generating a pressure wave in an elongated body operatively connected to a drop hammer |
US3927722A (en) * | 1974-02-08 | 1975-12-23 | Leonard L Frederick | Pile driving moving cylinder hammer with valved, fixed piston |
US4020804A (en) * | 1975-12-08 | 1977-05-03 | Fmc Corporation | Diesel pile hammer with vent for starting |
US4079794A (en) * | 1975-11-17 | 1978-03-21 | Van Kooten, B.V. | Cylinder piece for a pile driving ram |
US4187917A (en) * | 1977-11-30 | 1980-02-12 | Hydroacoustics, Inc. | Pile driver |
US4257488A (en) * | 1974-05-20 | 1981-03-24 | Van Kooten B.V. | Guide frame for a pile driving device |
US4465145A (en) * | 1975-12-20 | 1984-08-14 | Koehring Gmbh | Cushioned drive cap for a pile driver |
US4473123A (en) * | 1982-08-05 | 1984-09-25 | Raymond International Builders, Inc. | Diesel hammer capable of delivering uplift blows and method of using same |
US4523647A (en) * | 1983-03-16 | 1985-06-18 | International Construction Equipment, Inc. | Power hammer |
US4580641A (en) * | 1983-04-28 | 1986-04-08 | Raymond International Builders, Inc. | Method and apparatus for starting diesel type hammers |
US4860835A (en) * | 1985-12-23 | 1989-08-29 | Gebruder Lindenmeyer Gmbh | Diesel type pile-driver |
US5117924A (en) * | 1991-01-15 | 1992-06-02 | Berminghammer Corporation Limited | Energy transfer unit for a pile driver |
US5727639A (en) * | 1996-03-11 | 1998-03-17 | Lee Matherne | Pile driving hammer improvement |
US6102133A (en) * | 1995-08-11 | 2000-08-15 | Delmag Maschinenfabrik Reinhold Dornfeld Gmbh & Co. | Ram |
US6595087B2 (en) * | 2001-11-21 | 2003-07-22 | Snap-On Technologies, Inc. | Encapsulated dead blow hammer with improved skeleton |
US6634324B1 (en) * | 2001-03-29 | 2003-10-21 | Delmag Gmbh & Co, Kg | Diesel pile hammer |
US6942430B1 (en) * | 2004-03-10 | 2005-09-13 | Paul W. Suver | Rotary driver for pipe piling |
US20100303552A1 (en) * | 2009-05-27 | 2010-12-02 | American Piledriving Equipment, Inc. | Helmet adapter for pile drivers |
US8763719B2 (en) * | 2010-01-06 | 2014-07-01 | American Piledriving Equipment, Inc. | Pile driving systems and methods employing preloaded drop hammer |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6557647B2 (en) * | 2000-05-30 | 2003-05-06 | American Piledriving Equipment, Inc. | Impact hammer systems and methods |
DE102004062043A1 (en) * | 2004-12-23 | 2006-07-13 | Delmag Gmbh & Co. Kg | Dieselhammer |
CN102031779B (en) * | 2010-11-16 | 2012-07-25 | 上海申启星海洋工程有限公司 | Dual-guide internal cooling diesel pile hammer |
-
2014
- 2014-03-28 EP EP14162394.2A patent/EP2924171B1/en not_active Not-in-force
-
2015
- 2015-03-20 US US14/663,549 patent/US20150275458A1/en not_active Abandoned
- 2015-03-27 CN CN201510138543.4A patent/CN104947667A/en active Pending
Patent Citations (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2723532A (en) * | 1955-11-15 | Pile driving cap block | ||
US886193A (en) * | 1907-11-12 | 1908-04-28 | Frank L Aymond | Compressed-air-cushion block. |
US2633832A (en) * | 1949-07-22 | 1953-04-07 | Syntron Co | Diesel hammer |
US3130762A (en) * | 1961-06-21 | 1964-04-28 | Henry K Kerr | Hammer with detachable striking head faces |
US3788402A (en) * | 1970-12-29 | 1974-01-29 | Bolt Associates Inc | Automatically self-regulating variable-stroke, variable-rate and quiet-operating pile driver apparatus |
US3721095A (en) * | 1971-08-23 | 1973-03-20 | Bolt Associates Inc | Controllable force method and system of driving piles |
US3797585A (en) * | 1971-10-18 | 1974-03-19 | B Ludvigson | Apparatus for generating a pressure wave in an elongated body operatively connected to a drop hammer |
US3927722A (en) * | 1974-02-08 | 1975-12-23 | Leonard L Frederick | Pile driving moving cylinder hammer with valved, fixed piston |
US4257488A (en) * | 1974-05-20 | 1981-03-24 | Van Kooten B.V. | Guide frame for a pile driving device |
US4079794A (en) * | 1975-11-17 | 1978-03-21 | Van Kooten, B.V. | Cylinder piece for a pile driving ram |
US4020804A (en) * | 1975-12-08 | 1977-05-03 | Fmc Corporation | Diesel pile hammer with vent for starting |
US4465145A (en) * | 1975-12-20 | 1984-08-14 | Koehring Gmbh | Cushioned drive cap for a pile driver |
US4187917A (en) * | 1977-11-30 | 1980-02-12 | Hydroacoustics, Inc. | Pile driver |
US4473123A (en) * | 1982-08-05 | 1984-09-25 | Raymond International Builders, Inc. | Diesel hammer capable of delivering uplift blows and method of using same |
US4523647A (en) * | 1983-03-16 | 1985-06-18 | International Construction Equipment, Inc. | Power hammer |
US4580641A (en) * | 1983-04-28 | 1986-04-08 | Raymond International Builders, Inc. | Method and apparatus for starting diesel type hammers |
US4860835A (en) * | 1985-12-23 | 1989-08-29 | Gebruder Lindenmeyer Gmbh | Diesel type pile-driver |
US5117924A (en) * | 1991-01-15 | 1992-06-02 | Berminghammer Corporation Limited | Energy transfer unit for a pile driver |
US6102133A (en) * | 1995-08-11 | 2000-08-15 | Delmag Maschinenfabrik Reinhold Dornfeld Gmbh & Co. | Ram |
US5727639A (en) * | 1996-03-11 | 1998-03-17 | Lee Matherne | Pile driving hammer improvement |
US6634324B1 (en) * | 2001-03-29 | 2003-10-21 | Delmag Gmbh & Co, Kg | Diesel pile hammer |
US6595087B2 (en) * | 2001-11-21 | 2003-07-22 | Snap-On Technologies, Inc. | Encapsulated dead blow hammer with improved skeleton |
US6942430B1 (en) * | 2004-03-10 | 2005-09-13 | Paul W. Suver | Rotary driver for pipe piling |
US20100303552A1 (en) * | 2009-05-27 | 2010-12-02 | American Piledriving Equipment, Inc. | Helmet adapter for pile drivers |
US8763719B2 (en) * | 2010-01-06 | 2014-07-01 | American Piledriving Equipment, Inc. | Pile driving systems and methods employing preloaded drop hammer |
Also Published As
Publication number | Publication date |
---|---|
EP2924171B1 (en) | 2016-07-13 |
EP2924171A1 (en) | 2015-09-30 |
CN104947667A (en) | 2015-09-30 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: DELMAG GMBH & CO. KG, GERMANY Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:JERCH, LEOPOLD;HEICHEL, MATTHIAS;SIGNING DATES FROM 20150319 TO 20150320;REEL/FRAME:035237/0079 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |