JPH11294057A - In hole hammer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in hole hammer which is short and compact so that the cost for a work head can be small. SOLUTION: An in hole hammer to bore the ground is provided with a slender hollow housing 10 to carry a built-in striking piston 24 in a piston chamber 22. A replaceable boring head is screw-connected to a forward end of the housing 10. The striking piston 24 gives an impact to a forward wall (forming the piston chamber 22) of the housing 10, and the impact energy for forward drive is transmitted to the boring head. The boring rod to push the in hole hammer forward and to turn the hammer around the axis in the longitudinal direction is connected to a rear end of the housing 10 through a connection piece 54. The connection piece 54 is fixed to the housing 10 in a slidable and non- rotational manner. The impact energy in the axial direction brought by the striking piston 24 is transmitted to the boring rod.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substantially cylindrical housing and a striking piston which is actuated by a pressure medium in a piston chamber of the housing and is movable back and forth.
ton), a replaceable work head to which the striking energy of the striking piston is transmitted, a non-rotatable connection of the hammer to the boring rod and a pressure medium conductor.
An in-hole hammer including a connection piece non-rotatably connected to a housing for connecting a re-medium conductor.

[0002]

BACKGROUND OF THE INVENTION In-hole hammers are commonly used for boring on gravel or stony ground, especially for working on rocky terrain. In such a use case, the inhammer is pressed and held from behind by a boring rod and rotated continuously.

[0003] A pressure medium (generally compressed air) enters the hammer from behind and moves a striking piston inside the hammer. The striking piston is a work head, for example a boring crown, in which the boring crown is not fixed to the housing but is guided by a keyed shaft rotatably and longitudinally shiftable in the housing. Shock. The key spline must be relatively long so that high torques can be reliably transmitted simultaneously with the mechanical impact. In other words, the in-hole hammer is often relatively long, since a longitudinal shift between the housing and the boring crown must be reliably possible. And boring crowns are relatively heavy and expensive due to their length. Also, the boring crown is a worn part and must be replaced frequently, causing a relatively high operating cost to drive the in-hole hammer.

[0004] It is a basic object of the present invention to provide a short and compact inhaul hammer so that the cost required for the work head is low.

[0005]

SUMMARY OF THE INVENTION To achieve the above objects, the present invention provides a work head which is firmly but interchangeably fixed to the front end of a housing and an impact surface for a striking piston is substantially at the axis of the hammer. It is configured to be the front wall of a vertically arranged piston chamber.

In the present invention, the work head can be made short and therefore relatively light. The boring crown is affordable because the shaft previously required for boring crowns is eliminated. Also, since the impact piston strikes the front wall of the piston chamber instead of the rear shaft, the overall length of the hammer is reduced by at least the conventionally required length of the shaft. If the in-hole hammer is short, it is necessary to work from a narrow squeezed hole or from an already installed sewer pipe (its diameter is usually 1200 to 1600 mm), such as when connecting pipes from homes to the sewer pipe vertically. It is particularly advantageous when there is.

[0007] In order to facilitate the replacement of the work head, it is desirable to insert the work head in a threaded manner into the front extension provided with the threaded portion of the housing. Since this threaded connection (of the housing and the work head) can be very stiff due to the combination of the hammer movement and the rotary movement when the hammer is actuated, so that this connection can be loosened again. It is desirable to place a separation ring between the work head and the housing. When the housing is loosened from the threaded connection with the work head, the separating ring is broken by grinding so that the work head can be turned out of the threaded front extension.

In practice, at least one overflow channel for conducting the pressure medium from the piston chamber is formed at the front end of the housing and at the work head. Due to the overflowing pressure medium, during boring, the gravel (crushed stones) generated by the boring is transported backward through a gap in the boring crown. In this connection,
An outlet opening of the at least one overflow channel is provided in the front face of the work head facing the forward direction of the hammer. For example, at work sites where there is a mix of debris, including loam geological components, there is a risk that such (exit) openings will become blocked. To avoid this, it has been proposed to provide the outlet opening of at least one overflow channel on the side or rear face of the work head.

The work head has a conical sleeve surface for connection to a hard metal elemented boring crown or a pipe or ram ring (a ram ring insertable into a larger diameter pipe). A ram head used when driving into a pipe
May be configured as

When boring straight, the boring crown has a front surface perpendicular to the axis, the surface of which is provided with a hard metal element. The boring head may be provided with a control surface which, at least to some extent, controls the direction of advancement of the in-hole hammer, which intersects at an acute angle with the front surface perpendicular to the axis described above and which is similar to the front surface. The hard metal element has been applied.

The striking mechanism of the in-hole hammer has a first hole in which the striking piston is open rearward, the first hole receiving the first control tube, and the first control tube. Is fixed to the housing and is disposed coaxially within the housing of the piston chamber with radial spacing between the inner wall of the housing and the first control tube having an axial pressure medium channel. It is desirable to form it.

[0012] The hitting mechanism of the in-hole hammer also
The striking piston further has a second bore opening forward, the second bore receiving a second control tube, which is fixed to the housing and the inner wall of the housing. It is preferably arranged coaxially inside the housing of the piston chamber, with a radial spacing between it and the second control tube having an axial pressure medium channel.

[0013] The striking mechanism also has at least one control opening formed in each of the walls surrounding the first hole and the second hole (of the striking piston). Formed to cooperate with the corresponding open end of the control tube to control the flow of pressure medium into or out of the space between the front end of the striking piston and the impact surface. Is done.

According to the following preferred embodiments of the present invention,
The annular space filled with gas is the first
Between the first control tube and the inner wall of the piston chamber, in which the striking piston is guided by a wall surrounding the first control tube. The gas (usually air) that fills this annular space is compressed by the backward movement of the percussion piston, thus dampening its backward movement. In addition, the compressed air assists the next forward movement of the piston during the backward movement of the (hitting) piston, so that the annular space also functions as a pressure accumulator. This significantly increases the impact energy and the impact piston provides a sufficient impact on the front impact surface.

In the in-hole hammer of the present invention,
Since the impact energy is transmitted to the entire hammer housing, if the housing is firmly fixed to the boring rod, the impact energy will also be transmitted to the boring rod, and there is a danger of the rod being destroyed Will be. In order to prevent this, in the present invention, the connection piece has a connection portion and a guide portion. The connection part is connectable to the boring rod and the pressure medium conductor. The guide also guides the connecting piece in the housing and slides the connecting piece axially between the two end positions.

In the housing, there is formed an annular space surrounding the guide portion (the annular space surrounds the guide portion by its length). One (axial) side of the annular space is closed by a seal ring fixed to the housing end and the other side is closed by a seal ring fixed to the guide. The annular space also communicates with a pressure medium (fluid) channel extending through the connecting piece via a radial hole formed in the guide. The housing of the hammer is thus axially movable with respect to the connecting piece and with respect to the boring rod connected to the connecting piece.

This axial movement is dampened by air pressure trapped between the two seal rings. Also, the pressurized air flowing into the annular space between the two seal rings through the radially formed holes will cause the housing to subsequently move as long as the air pressure compresses the two seal rings away from each other. This has the effect of being set at the end position.

[0018] Other features and advantages of the present invention will be apparent from the following description, which describes the invention in specific embodiments with reference to the accompanying drawings.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The in-haul hammer shown in FIGS. 1 and 2 has a longitudinally extending shaft 11 and a housing 1 in the form of a cylindrical tube.
Has zero. The housing 10 is closed at its front end (left end in FIGS. 1 and 2) and has an axially extending hole 1.
2 and at its foremost end an extension 16 with an external thread 14. The rear end (the right end in FIGS. 1 and 2) of the tube-shaped housing 10 is closed by the base 18. The base part 18 has a screw part 20, and is screwed into the rear end of the housing 10 provided with a screw part through the screw part 20.

The housing 10 is configured to surround a piston chamber 22 in which a striking piston (indicated by reference numeral 24) is slidably guided.

The striking piston 24 has a first hole 26 opened rearward, and a control tube 28 formed integrally with the base portion 18 extends into the first hole 26. Also, the first hole 2
6 extends in the piston chamber 22 coaxially with the housing 10 while being spaced from the inner wall 30 of the housing 10 in the radial direction. Of course, the base part 18 and the control pipe 28 may be separate parts. The striking piston 24 further has a second hole 32 opened in the axial direction (upstream side) from the front end thereof, and the front control pipe 34 is received in the second hole 32. The control tube 34 fits snugly into the hole 12 of the housing 10 and extends through the piston chamber 22 (to the right in the figure) coaxially with the housing 10 while being spaced radially from the inner wall 30 of the housing 10. First hole 2
6, and a piston wall portion 36 surrounding the second hole 32,
In 38, control openings 40 and 42 are formed. The control openings 40 and 42 allow the internal space of the corresponding hole to communicate with the space outside the striking piston 24, that is, the piston chamber 22.

The outer diameter of the impact piston 24 and the housing 10
Has a coincidence only in the rear end region 44 and the head region 46 of the striking piston 24, so that the striking piston 24 slides along the inner wall 30 only in these partial regions 44, 46. In the remaining part of the striking piston 24, the outer diameter of the piston 24 is
0 is slightly smaller than the inner diameter. On the wall surface of the rear end area 44 of the striking piston 24 (where the striking piston 24 slides along the inner wall 30 and along the outer wall of the control tube 28), at the side of the striking piston 24, the inner wall 30 and the control tube Seals 48 and 50 are provided to hermetically seal an annular space (space) 52 between the control pipe 28 and the control pipe 28 (the control pipe 28 is
At the right end in the figure, it is closed by the screw portion 20 of the base portion 18). Therefore, the annular space 52 has no communication with the outside.

The connection between the above-mentioned in-hole hammer and a boring rod (not shown) is made through a connecting piece indicated by reference numeral 54. This connection piece is connected
6 and a guide portion 58, and the guide portion 58 is
And inserted into the base portion 18 so as to be coaxial. The cylindrical end 60 of the guide 58 extends into the bore of the control tube 28. Portion 6 from this end portion 60 to the connection portion 56
2 is received in a recess 64 whose outer surface is formed in a hexagonal shape and whose cross-section formed in the threaded portion 20 of the base portion 18 is hexagonal (that is, a shape complementary to the cross-section of the portion 62). The connecting piece 54 is rotatably fixed to the base 18 (and thus to the housing 10).

An annular chamber 66 surrounding the guide portion 58 of the connecting piece 54 has a threaded portion 20 connected to the end of the base portion 18.
(In the figure) to the right. The annular chamber 66 is closed from the outside by a seal ring 68 fixed to the base portion 18. The seal ring 68 is connected to the connection piece 5
4 is slidable on the cylindrical annular surface 70. In the hexagonal portion 62 of the connecting annular surface 72 of the guide portion 58,
Another seal ring 74 is provided. The other seal ring 74 is connected to the connecting piece 54 and is slidable on an inner wall 76 which is a part of the base 18 defining an annular space 66 of the base 18. is there. The annular space 66 includes the base 1
8 communicates with the outside air through a hole 78 formed in the radial direction, and through a radial hole 80 formed in the guide portion 58 of the connection piece 54, a channel 82 (channel 82).
Extends axially through the entire connection piece 54).

The portion of the channel 82 that extends through the connection 56 has a polygonal cross section and receives a pin of a complementary shape (to the polygon of the channel 82) of the boring rod, and Securely connect the hammer (but allow the hammer to rotate). Connection part 5
The inclined surface 84 at the insertion end of 6 presses the spring bolt provided on the connection pin of the boring rod radially inward until the connection pin is pushed into the connection portion 56, and presses the bolt in the radial direction of the connection portion 56. The hole 86 is latched so that the connecting pin does not come out of the state received by the connecting portion 56 even when the boring rod slides outward.

Next, the operation of the above-described in-haul hammer striking mechanism will be described.

By means of a hollow boring rod (not shown) inserted in the connection 56, pressurized air is passed through the channel 82 of the connection piece 54 and the bore of the control tube 28 of the (first) impact piston 24. It is sent to the hole 26. One may start with the striking piston 24 lowered rearward, as shown in FIG. The pressurized air cannot escape from (the space of) the first hole and therefore
The impact piston 24 in the state shown in FIG.
Driven to the position shown in FIG.
The second front wall (surface) 87 is impacted. Thereby, the striking energy of the striking piston 24 is transmitted to the housing 10 and the base 18 connected thereto. Immediately before reaching the end shown in FIG. 2, the control opening 40 formed in the wall 36 of the striking piston 24 passes through the open edge (left in the figure) of the control tube 28, so that the pressurization The generated air is released radially outward from the space between the control pipe 28 and the first hole 26 through the control opening 40. On the other hand, since the seal 48 and the seal 50 close the annular gap between the outer wall of the striking piston 24 and the inner wall 30 of the housing 10, the pressurized air cannot escape backward. However, the pressurized air escapes forward through the annular gap shown in FIGS. In other words, the pressurized air flows into a groove parallel to the axis of the hammer (the striking piston 24).
(Which is located on the outer surface of the head portion 46 and is shown in phantom in the figure). When the air reaches the front of the piston chamber 22, it in turn drives the striking piston 24 from the position shown in FIG. 2 to the position shown in FIG. This is due to the difference in pressure applied to the piston surface. When the control opening 42 provided in the wall 38 of the striking piston 24 has passed the right open end (in the figure) of the control tube 34, the connection between the piston chamber 22 and the control tube 34 to the outside is opened. Occurs via section 42. Impact piston 24
Is moved further rearward, the control opening 40 provided in the wall 36 of the piston 24 again passes through the open edge of the control tube 28, and the first hole 26 in the striking piston 24 is closed again. The pressure fluid flowing into the first hole 26 drives the striking piston 24 to the left again in the figure, and the above process is repeated.

The above-described movement of the striking piston 24 to the left in the drawing is caused by pressurized air (the pressurized air is present in the hermetically closed annular space 52 and the movement of the striking piston 24 to the right in the drawing). Is compressed). Therefore, the air filling the annular space 52 effectively functions as a resilient air cushion for dulling the striking piston 24 when the striking piston 24 moves backward (to the right in the drawing), It also functions as a pressure accumulator that drives the piston 24 forward (to the left in the figure) again.

When the striking piston 24 impacts the front face 87 of the housing 10, the housing 10 is forward (ie, axially immovably connected to the connecting rod) with respect to the boring rod and the connecting piece 54. FIG.
To the left). If these movements were transmitted directly to the boring rod, the boring rod would quickly break. For this reason, a length compensating and damping device
An apparatus is provided between the hammer and the boring rod so that the connection piece 54 can move relative to the housing 10 and the base 18. In the illustrated embodiment, this length correction and shock absorber acts aerodynamically. In the in-hole hammer in the position of FIG. 1, pressurized air flows through the channel 80 into the annular space 66 between the seal ring 68 and the seal ring 74.

When the seal ring 68 and the seal ring 74 move in a direction approaching each other, both the rings 68, 74
Air trapped therebetween is forced out through the radial holes 80, thus dampening movement of the housing 10 relative to the connection piece 54. At this time, the seal ring 74
The air is exchanged between the hollow space formed on the rear side (with respect to the seal ring 68) and the surrounding air through the hole 78. As a result, the pneumatic pressure drives the seal ring 68 and the seal ring 74 again, and both are separated. If used properly technically, that is, if the boring rod is always held in a moderately cushioned (pressure) state, the sealing rings 68, 74 will come into contact with each other during use of the in-hole hammer of the invention. There is no.

Instead of the aerodynamic length assurance (shock absorbing) device, a device for solving this mechanically may be provided. In this case, two seal rings 68, 7
Between 4, a helical compression spring is installed.

FIGS. 3 and 4 show a first embodiment of a boring head or boring crown 88 which is threadably inserted into the threaded extension 16. As shown in FIG. 3, when the boring crown 88 is threadedly inserted into the extension 16, the separation ring 90 is compressed between the boring crown 88 and the housing 10.
When the in-hole hammer is activated, the threaded connection between the boring crown 88 and the housing 10 is so firm that the boring crown 88 does not come loose from the housing 10. Bowling crown 8
If the separating ring 90 is broken, for example by grinding, when removing 8, the boring crown 88 can be removed from the screw-type extension 16 without any effort.

In the example shown in FIG. 3, the boring crown 88 has a front surface 92 perpendicular to the axis 11 of the hammer and a control surface 94 intersecting the front surface 92. Both the front surface 92 and the control surface 94 are provided with a hard metal element (material made of) 96. The control surface 94
It does not affect the boring direction while the in-hole hammer is rotating. Conversely, if the in-haul hammer is not rotating, the control surface 94 affects the boring direction. That is, the control surface 94 can change the direction of the in-hole hammer, that is, the direction of boring, to a desired direction.

In the example shown in FIG. 3, the boring crown 88 has an exhaust channel 98 oriented diagonally rearward as shown. Exhaust discharged from the front control pipe 34 communicates with outside air through the exhaust channel 98. In this example, the outlet opening 100 of the exhaust channel 98 is located behind the boring crown 88 and is configured to prevent clogging with gravel and soil generated during boring.

In the example shown in FIGS. 5 and 6, the exhaust channel 100 is directed toward the front face 92 and the control face 94, and thus is open in the forward drive direction. This configuration is advantageous because the exhausted air blows away the gravel generated during boring and transfers it backward. However, this configuration example is not suitable for use in a mixed soil location that may include loam geology (such as loam geology may block exhaust channels 98).

FIG. 7 shows a boring crown 102 having only a front face perpendicular to the axis (of the hammer) and no control face, in contrast to the examples shown in FIGS. ing. The hammer itself is located inside the central tube of the transport screw indicated by reference numeral 104 and is connected to a boring rod 108. The side of the boring rod 108 is surrounded by spiral wings like the transport screw 104, and the body of the boring rod 108 and the wings form the transport screw 110. The transport screw 110, like the transport screw 104, is located along the inner wall of a sheath-shaped case 112 that defines the hole being excavated. The conveying screws 104 and 110 convey the gravel generated by the boring backward.

Finally, FIG. 8 shows an in-hole hammer of the invention of the type described in connection with FIGS. 1 and 2, wherein a ram head (a ra) is used instead of a boring crown.
An in-haul hammer with an mhead 114 is shown. The ram head 114 has a conical sleeve surface 116. This sleeve surface 116 may be overlaid on the pipe into which the boring rod is to be driven, or the sleeve surface 116 may be overlaid on a ram ring and then inserted into a pipe of appropriate diameter.

[Brief description of the drawings]

FIG. 1 is a partial schematic view of an in-hole hammer (and its axis) embodying the present invention and shown with its striking piston in a rearward position.

FIG. 2 is a partial schematic view of the in-hole hammer of FIG. 1 showing a state in which a striking piston is in a front position thereof.

FIG. 3 is a side view of an in-haul hammer embodying the present invention with a boring crown (shown in cross-section) according to a first embodiment.

FIG. 4 is a front view of the bowling crown of FIG. 3;

FIG. 5 is a side view of an in-hole hammer embodying the present invention with a boring crown (shown in cross section) according to a second embodiment.

FIG. 6 is a front view of the bowling crown of FIG. 5;

FIG. 7 is a schematic partial cross-sectional view of an in-hole hammer according to the present invention used in a coated hole.

FIG. 8 is a view corresponding to FIGS. 3 and 5 showing an in-haul hammer of the invention with a ram head (shown in cross section);

[Explanation of symbols]

 Reference Signs List 10 housing 11 (longitudinal) shaft 22 piston chamber 24 striking piston 54 connecting piece 87 front wall 88 boring head (boring crown)

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[Procedure amendment]

[Submission date] August 25, 1998

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Change

[Correction contents]

FIG.

FIG. 4

FIG. 6

FIG. 2

FIG. 3

FIG. 5

FIG. 7

FIG. 8 ────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 9, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Wherein the outlet opening of the at least one of said overflow channels, the in-hole hammer in hole hammer according to claim 1 wherein formed on the front surface of the work head facing the upstream side of the advancing direction.

5. At least one outlet opening of the overflow channel, in the hole hammer according to claim 1 wherein formed on the side surface or the posterior surface of the work head.

6. The in-hole hammer according to claim 1, wherein the work head is a boring crown provided with a hard metal element.

7. The boring crown, and a substantially vertical front and control surface intersecting this front and obliquely to the shaft, according to claim hard metal elements to the front and the control surface is subjected 6 In-hole hammer as described.

8. The ram head for driving a pipe into a pipe, wherein the ram head has a conical sleeve surface, and the sleeve surface is connected to a pipe into which the ram head is driven. 3. The in-hole hammer according to claim 1, wherein the ram head is connected to a ram ring insertable into a pipe into which the ram head is driven.

9. the striking piston further has a first hole which is open to the rear, inner wall of the inside the piston chamber of the first control tube is the first hole which is firmly fixed to the housing A second hole disposed radially away from the first hole (in the piston chamber) and coaxial with the first hole, wherein the striking piston is open forward; And the second control tube is fixedly secured to the housing coaxially with the interior of the housing in the piston chamber at a radial distance from the inner wall of the housing, the second hole being disposed in the housing. Has an axially extending pressure medium overflow channel, at least one control opening is formed through the wall of the striking piston corresponding to each of the first and second holes,
The control openings cooperate with the corresponding open ends of the control tubes to flow into or out of the space between the front end of the impact piston and the impact wall. 2. The in-hole hammer according to claim 1, wherein

10. A closed annular space filled with gas is formed between the first control pipe and the inner wall of the piston chamber, and the striking piston defines the first control pipe. claim is guided by the wall portion surrounding 9
In-hole hammer as described.

11. The in-hole hammer and relative-in hole hammer according to claim 1, further comprising or not to allow the movement or the length correction mechanism dampened between the boring rod.

12. The connection piece has a connection and a guide, the connection being connectable to a boring rod and to the pressure medium (supply) conductor, the connection piece having two ends in the housing. between parts is guided so as to slide in the axial direction, the connecting piece is resiliently biased in its end position, according to claim 1 1, wherein said connecting piece at this position extend further into the housing with the guide portion In-hole hammer.

13. An annular space in the housing (space) is formed, surrounding the space thereof by the length the guide portion of the annular space of the annular axially extending, firmly to the housing A helical compression spring is disposed between the two rings, wherein the helical compression spring is disposed on one side of the fixed ring and on the other side of another ring fixedly secured to the guide. 12. The in-hole hammer according to 12 .

14. A sealing structure in which an annular space is formed in said housing, said annular space surrounds said guide portion by a length thereof, and said annular space extending in the axial direction is fixed to said housing. Closed on one side by a ring and closed on the other side by a ring firmly fixed to the guide, the annular space is formed in the pressure medium channel passing through the connecting piece and in the guide 13. The in-hole hammer according to claim 12 , wherein the in-hole hammer communicates through a defined radial hole.

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Claims (15)

[Claims] An in-hole hammer having a longitudinally extending axis, which is actuated by a substantially cylindrical housing and a pressure medium introduced into a piston chamber of the housing, and is movable back and forth. A striking piston, a replaceable work head to which the striking energy of the striking piston is transmitted, a non-rotatable connection of the in-hole hammer to a boring rod, and a pressure medium conductor.
a work piece fixedly but removably secured to the front end of the housing in front of the connection piece, wherein the work head is fixedly and removably fixed to the housing. An impact hammer of the impact piston is a front wall of the piston chamber substantially perpendicular to an axis extending in the longitudinal direction of the inhaul hammer. 2. The in-hole hammer according to claim 1, wherein the work head is screw-mounted to an extension provided with a thread of the housing. 3. The in-hole hammer according to claim 2, wherein a separation ring is provided between the work head and the housing. 4. The in-hole hammer according to claim 1, wherein at least one overflow channel is formed in the front end of the housing and the work head to exhaust the pressure medium from the piston chamber. 5. The in-hole hammer according to claim 4, wherein an outlet opening of at least one overflow channel is formed in a front surface of the work head facing an upstream side in a forward direction of the in-hole hammer. 6. The in-hole hammer according to claim 4, wherein an outlet opening of at least one overflow channel is formed in a side surface or a rear surface of the work head. 7. The in-hole hammer according to claim 1, wherein the work head is a boring crown provided with a hard metal element. 8. The boring crown has a front surface substantially perpendicular to the axis and a control surface obliquely intersecting the front surface, and the front surface and the control surface are provided with a hard metal element. In-hole hammer as described. 9. The method according to claim 1, wherein the work head is a ram head for driving a pipe, wherein the ram head has a conical sleeve surface, and the sleeve surface is connected to a pipe on which the ram head is driven. 3. The in-hole hammer according to claim 1, wherein the ram head is connected to a ram ring insertable into a pipe into which the ram head is driven. 10. The piston according to claim 1, wherein said striking piston further has a first hole opened rearward, and a first control tube fixedly secured to said housing has an inner wall of said piston chamber inside said first hole. A second hole disposed radially away from the first hole (in the piston chamber) and coaxial with the first hole, wherein the striking piston is open forward; And the second control tube is fixedly secured to the housing coaxially with the interior of the housing in the piston chamber at a radial distance from the inner wall of the housing, the second hole being disposed in the housing. Has an axially extending pressure medium overflow channel, wherein at least one control opening is formed through the wall of the striking piston corresponding to each of the first and second holes; Control opening Cooperating with an open end of the corresponding control pipe to control a pressure medium flowing into a space between a front end of the impact piston and the impact wall or a pressure medium (fluid) overflowing from the space. Item 14. An in-hole hammer according to Item 1. 11. A closed annular space filled with gas is formed between the first control pipe and the inner wall of the piston chamber, and the striking piston defines the first control pipe. 2. Guided by said surrounding wall.
0 in-hole hammer. 12. The in-hole hammer of claim 1, further comprising a length correction mechanism that allows or reduces relative movement between the in-hole hammer and the boring rod. 13. The connection piece has a connection portion and a guide portion, the connection portion being connectable to a boring rod and the pressure medium (supply) conductor, and the connection piece having two ends in the housing. 13. The connection piece of claim 12, wherein the connection piece is resiliently biased at its end position, guided axially slidably between the parts, at which position the connection piece extends with the guide portion further into the housing. In-hole hammer. 14. An annular space (space) is formed in the housing, and the annular space surrounds the guide portion by its length, and the annular space extending in the axial direction is firmly attached to the housing. A helical compression spring is disposed between the two rings, wherein the helical compression spring is disposed on one side of the fixed ring and on the other side of another ring fixedly secured to the guide. 13. The in-hole hammer according to 13. 15. A sealing wherein an annular space is formed in the housing, the annular space surrounds the guide by a length thereof, and the annular space extending in the axial direction is fixed to the housing. Closed on one side by a ring and closed on the other side by a ring firmly fixed to the guide, the annular space is formed in the pressure medium channel passing through the connecting piece and in the guide 14. The in-hole hammer according to claim 13, wherein the in-hole hammer communicates via a defined radial hole.