JPS602471B2 - air hammer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rock hammer.

This invention provides a hammer for use in a normal rotary rock drill, which is easier to manufacture, lower in cost, smaller in size, better in performance, and more trouble-free than conventional ones. Its purpose is to.

Hereinafter, the structure of the present invention will be explained with reference to embodiments shown in the drawings.

This hammer has a hollow cylindrical housing 10,
This housing 10 has an inner flap part and a threaded part formed vertically symmetrically, so that it can be used upside down.

The large inner diameter portions 11 at both ends of the housing 10 are threaded on their inner peripheral surfaces. Adjacent to the large inner diameter portions 11 at both ends, an upper pressure chamber 12 and a lower pressure chamber 13, both of which also have large inner diameters, are formed, and the upper pressure chamber 12
The inner diameter between the lower pressure chamber 13 and the lower pressure chamber 13, that is, the center portion of the housing 10 is also increased to form a central pressure chamber 14. At the boundaries of these large inner diameter parts, there are
Upper shoulder 15, lower shoulder 16, upper piston bearing 17
and a lower piston bearing 18 are formed. At the upper end of the housing 10, a flange on the outer periphery is attached to the upper shoulder portion 1.
5, the air introduction member 19 is engaged with the housing 10.
It is held in place by a top sub 20 screwed into the top end of the .

This upper end sub 20 connects the housing 10 to a drill rod (not shown) of a rock drill, and has a screw for connection and a shaft hole 21 for introducing compressed air through the drill core. A valve seat of a check valve 22 biased by a spring is provided on the circumferential surface of the borehole 21 of the saps 20. Shaft hole 21
The check valve 22 is opened by the compressed air introduced into the hole 21 , and the air passing between the lower large inner diameter part of the borehole 21 and the upper part of the air introduction member 19 is transferred to the radial through hole 23 of the air introduction member 19 . The air is introduced into the housing 10 through the air supply pipe 24 coaxial with the air introduction member 19. Upper piston bearing 17 and lower piston bearing 18'
On the other hand, the upper shaft hole 26 of the stone 25 is capable of swinging.
The air supply pipe 24 is fitted in a removable manner, and a choke passage 28 having a diameter is formed between the upper shaft hole 26 and the lower shaft hole 27.

A drive support 31 is provided in the inner flanges 11 at the lower end of the housing 10.
is screwed into the drive sub 31, and the bit 2 is screwed into this drive sub 31.
9 shanks 30 are flushably fitted.

Further, a ring-shaped stopper 32 is also fitted around the shank 30 of the bit 29 between the drive support 31 and the lower shoulder portion 16 of the housing 10. The upper end of the shank 30 of the bit 29 has a slightly larger outer diameter and forms an anvil 33, and the downward movement of this anvil 33 is restricted by the stopper 32. bit 29
The lower end of the shank 30 has a hexagonal shape, and the lower end of the inner hole of the drive sub 31 also has a similar hexagonal shape to prevent rotation of the bit 29 relative to the housing.
A lower end portion of a sliding seal tube 35 is fixed to the upper end of an air flow path 36 that is formed in the shank 30 through the anvil 33 and branches into a plurality of diagonal holes at the lower end of the bit 29. When the piston 25 descends to the position where the lower end of the piston 25 touches the anvil 33 (the position shown in FIG. 1), the seal tube 35 can be removed from the piston 25. 1st
When the piston 25 rises as shown in the figure, compressed air introduced from the air supply pipe 24 enters the upper shaft hole 26 of the piston 25.
One end is closed to this upper wisteria hole 26, and the other end is the housing 10.
It opens into the upper pressure chamber 12 of the piston 25 and is fed into the upper pressure chamber 12 via a pressure boat 37 installed at an angle on the wall of the piston 25, and lowers the piston 25 to the position shown in FIG.

An exhaust boat 38 is formed along the longitudinal direction of the piston 25, with one end opening at the upper end of the piston 25 and the other end opening at the outer peripheral surface of the piston 25. The compressed air in the upper pressure chamber 12 is passed through the exhaust boat 38 to the central chamber 14 of the housing 10. Note that this exhaust boat 38 is closed by the upper piston bearing 17 when the piston 25 is raised (see FIG. 1).
The piston 25 further has a lower wall extending therethrough.
An exhaust boat 39 having one end closed to the lower shaft hole 27 and a pond end closed at its outer circumferential surface is mirror-slanted. The compressed air sent into the central chamber 14 of the housing 10 as described above is transferred to the exhaust boat 39 and the seal pipe 35.
It is discharged through the air passage 36 of the bit 29, and blows off rock chips and the like generated during rock drilling work. At a position substantially parallel to the exhaust boat 39, the piston 25
An inclined pressure boat 40 is installed through the wall of the vessel. When the piston 25 descends to the position where it contacts the ampillar 33 (FIG. 2), the air supply pipe 2
The compressed air that has entered the upper shaft hole 26 of the piston 25 through the pressure boat 40 is sent into the lower pressure chamber 13 of the housing 10 and causes the piston 25 to rise. When the piston 25 begins to rise, the pressure boat 40 is immediately closed by the lower piston bearing 18.
When the piston 25 rises and comes out of the seal tube 35, the compressed air in the lower pressure chamber 13 flows into the lower shaft hole 2 of the piston 25.
7 and the exhaust boat 39 into the central pressure chamber 14 of the housing 10 . As the piston 25 rises, the air in the upper pressure chamber 12 of the housing 10 is compressed and absorbs the shock, and the pressure boat 37 disengages from the upper piston bearing 17 and opens, causing the piston 25 to descend again as described above. Before this occurs, a certain amount of recoil thrust is generated. During rock drilling, the drive sub 31 is loosened against the bit 29 by the pressure applied to the hammer (see FIGS. 1 and 2). Now, as shown in FIG. 3, when the housing 10 is raised from the bit 29, the fan 33 comes into contact with the stopper 32, and the piston 25
In its downward stroke, the relative relationship with the housing 10 is lowered further than in the above case, and the hole 41 radially penetrated through the lower end of the common trachea 24 is exposed from the upper end of the piston 25, and the upper part of the housing 10 is exposed. The pressure chamber 12 is closed. For this purpose, the compressed air fed into the air supply pipe 24 exits through the hole 41 and enters the upper pressure chamber 12, and then passes through the exhaust boat 38 and enters the central chamber 14 of the housing 10. The air that has entered the central chamber 14 further passes through the piston 25
It enters the lower pressure chamber 13 of the housing 10 through the pressure boat 37, the upper shaft hole 26 and the pressure boat 40, and also enters the lower shaft hole 27 from the exhaust boat 39 of the piston 25,
Furthermore, it reaches the air passage 36 of the bit 29 via the seal pipe 35. Thus, by lifting the hammer off the work surface, the compressed air bypasses the piston 26, interrupting the operation of the hammer, and blowing away debris from the work surface. Since the hole diameter of the choke passage 28 in the piston 25 is set appropriately, compressed air passes through the air passage 36 of the bit 29 during normal operation of the hammer without interfering with the reciprocating movement of the piston 25. It can be flushed out.

In order to simplify the drawings and explanation, only one boat is shown on the piston 25, but it is considered a desirable embodiment to provide three boats on the piston 25.

[Brief explanation of the drawing]

Each of the figures in the drawings is a longitudinal cross-sectional view of an embodiment of the hammer of the present invention, in which Figure 1 shows a state in which the piston is fully raised, Figure 2 shows a state in which the piston is lowered, and Figure 3 shows a state in which the piston is lowered. The figures show the piston in a lowered position and the housing raised relative to the bit. 10...Housing, 12...Upper pressure chamber, 13...Lower pressure chamber, 14...Center pressure chamber,
20...Top end sub, 24...Air supply pipe,
25... Piston, 26... Upper shaft hole, 27... Lower shaft hole, 29.・・・． ...bit, 3
3... Anvil, 36... Air flow path, 37
...Pressure boat, 38,39...Exhaust boat, 40...
Pressure boat, 41... hole. FIG. 1. FIG. 2. FIG. 3,

Claims (1)

[Claims] 1. A tubular housing, an upper end sub connected to the upper end of the housing having a screw for connecting the housing to a drill rod of a rock drill and a shaft hole for introducing compressed air, and the upper end sub. An air supply pipe that communicates with the shaft hole of the housing, extends into the housing, is disposed coaxially with the housing, and has a radial hole at the lower end that can be opened and closed, and the lower end of the housing can be slid a certain distance. A bit having a shank attached to the bit, an air flow passage passing through the shank and the bit having an anvil formed at the inner end thereof, and protruding into the housing from the air flow passage along the axis of the housing. a sliding seal tube fixed to the shank, a piston that is slidably mounted in the housing and can collide with the anvil in its lowered position, and an upper pressure chamber formed in the housing near the upper end of the piston. a lower pressure chamber formed within the housing near the lower end of the piston; a central pressure chamber formed within the housing relative to the middle portion of the piston; and a central pressure chamber formed at the axis of the piston relative to the air supply pipe. an upper axial hole that is movable relative to the oscillating seal tube when the piston is in a descending state; A plurality of pressure ports penetrate through the wall of the piston to allow communication between the upper pressure chamber of the housing in the raised position of the piston and the lower pressure chamber of the housing in the lowered position of the piston, and the central pressure chamber of the housing. a plurality of exhaust ports penetrated through the wall of the piston to communicate the central pressure chamber with the upper pressure chamber of the housing in the lower shaft hole of the piston and in the lowered position of the piston; Machine air hammer. 2. The radial hole at the lower end of the air supply pipe is formed to open into the upper pressure chamber of the housing in the lowermost position facing the housing of the piston and anvil in which the housing is separated from the bit by the predetermined distance;
Compressed air is conducted from the air supply pipe through this hole to the upper pressure chamber of the housing, and is also conducted to the lower pressure chamber of the housing through the upper shaft hole of the piston and one pressure port to stop the vertical movement of the piston. , and a patent in which a portion of the compressed air is conducted to the air flow path of the bit via the upper shaft hole of the piston, the other pressure port, the central pressure chamber of the housing, the one exhaust port, and the sliding seal pipe. An air hammer according to claim 1.