Air Hammerfest

Written By Patents.Google

(Translate From Germany to English By Ivonne Fonseca 2019)

General Description

The invention relates to a pneumatic hammer with a stand, in which the drive mounted with the motor and crank mechanism, and an upper bracket for the reception of drive piston-cylinder unit and working piston-cylinder unit, with two cylinders in each case above and below the two piston connecting air lines, and arranged with a wall in the end of the drive cylinder air suction valve.

Such air hammers as known from a brochure (LS 1000d 0379 Gr.) From Bech' + Grohs GmbH, Hucheswagen from 1979 BE are known which have a control valve in the cylinder above the piston connecting air line, by means of which the work of Baer can be interrupted. In this case the working piston is held in its top dead center, currency rend the drive piston constantly sucks air through the continuous drive and its corresponding reciprocating motion and discharges again. This not only causes considerable noise but also the formation of oil mist as the air ejected always achieve a little oil in a finely divided form. This oil released into the atmosphere and provides an environment constitutes pollution. The existing significant Noisy development must be regarded as environmental impact.


Which the object underlying the invention is seen to provide an air hammer of the above type in which the pollution mentioned or debits largely dispensed with, and in particular both a noise attenuation is also a retention of the oil mist, which is in particular sondere idle important.

This object is inventively achieved in that the jib is designed as a substantially closed chamber in which both piston-cylinder units are arranged so that the interior of the chamber is connected via an oil separator and a filter with the outside air, and that at least a part of the walls of the chamber is soundproofed.

By using a chamber for the two piston-cy linder units, the oil mist-containing air is first of all collected at the exit of the upper air duct, so that it can not escape directly into the atmosphere. It can leak out then only through an oil separator and a filter, so that it is reliably ensured that the entrained oil is retained. The filter and the oil separator are also used for air supply to the chamber, but it has only the filter has a function to the effect that a penetration of dust into the housing to prevent, while the oil separator is merely for the passage of air. Further, the walls of the chamber are soundproofed to minimize noise pollution of the environment, which is already reduced by the chamber itself, on.

the volume of the chamber thereby is advantageous so large that the occurring at idle peak internal pressure is low lässigbar vernach, which also is used for noise attenuation.

the chamber is advantageously designed essentially box-shaped, such that the sound insulation can be made of which is arranged on the inner walls of the chamber soundproofing panels.

As an oil separator, a plurality of spaced has been proven in the manner of a labyrinth lamellae which Benach disclosed is near one of the drive piston-cylinder unit, the air opening along with filters having wall region of the chamber extending vertically. Such is off design easy to produce and also very more sam. Preference is given to the wall region of a narrow side of the chamber is formed, wherein the oil separator is arranged in an intermediate wall defining a compartment within the chamber, the width of the axial length formed of appropriate as a pot filter, the air opening surrounding filter corresponds.

In a further embodiment of the invention object to which the two piston-cylinder units supplied, air losses of the system balancing the supply air to be particularly well controlled in order to ensure proper function of the air hammers. For this purpose, it has proved advantageous that arranged in the end wall of the drive cylinder air intake valve on the one hand of a stationary valve plate with offset in distance from the circumference along a circle located through holes, and to make the other hand of an annular valve body having the through holes at the underside of the valve body covers and at reduced pressure in the cylinder against the pressure of a spring from the valve side can be lifted. This spring is advantageously a compression coil spring. It is preferably an embodiment in which on the outer side of the valve plate concentrically positioning plate a one is rotatably mounted and lockable, having through holes, which by rotating the adjustment plate to the through holes of the valve body are congruent for the purpose of infinitely changing the passage cross section of the valve.

The invention and its advantageous embodiments are described guide Example in more detail below with reference to an illustrated in the drawing.

It shows:

1 shows a longitudinal section through an air hammer according to the invention.

The air hammer shown in  comprises a stand 2, in which the drive 3 of thepneumatic hammer 1 with engine 4 and crank drive with crank disc 5 and the connecting rod 6 is mounted. There is provided an upper boom 7 for receiving an actuation piston-cylinder unit 8 and a working piston-cylinder unit 9, which is placed on the stand 2 at 10 and mounted in manner not shown. In the cylinder 11of the drive piston-cylinder unit 8 to be moved a drive piston 12 in the direction of arrow B back and forth in the cylinder 13 of the working piston-cylinder unit 9, a working piston fourteenth There are two cylinders each provided connecting air lines 15 and 16, namely ver binds the air line 15 the cylinders 11 and 13 above the pistons 12 and 14, while the air line 16 the cylinder below the pistons 12 and 13connects 11 and 13 together.

Further, a suction valve is provided Luftan 17 on the end wall of the cylinder 56. 11In the upper air duct 15, a control valve 18 is arranged, which the air duct terminates in the position shown 15 to the space 19 in the cylinder 13 top half of the working piston 14 and only the space 20 above the drive piston 12 in the cylinder 11 in arrow Rich tung A with the outside air combines. This is around the neutral position of the control valve 18th

Is shown  the control valve 18 is rotated counterclockwise so that the air line 15 is continuous and the discharge of air in the direction of arrow A inhibited, it is understood that the continuous reciprocation of the drive piston 12 in the direction of arrow B is a corresponding , cause opposite reciprocating movement of the working piston 14 in the direction of arrow c. The air in the cylinder chambers 19 and 20 and the air line 15 is practically completed, so that only losses due to leaks by means of the function of a check valve having Luftan suction valve are compensated 17th A potentially which builds up by such leaks in the cylinder chambers 22 and 23 and in line 16 overpressure relief via the openings 25balanced.

According to the invention, the boom 7 to be substantially closed chamber 28 is now formed, in which the two piston-cylinder units 8 are disposed. 9 The interior of the chamber 28 communicates only through an oil separator 26 and a filter 27 with the outside air. Finally, the walls of the chamber 28 are soundproofed. In the shown, preferred embodiment, the chamber 28 is substantially box-shaped, wherein the sound insulation consists of which is arranged on the inner walls of the chamber Sound insulation plates, which are indicated by dash-dotted lines at 29.

Suitably, the volume of the chamber 28 is so large that the occurring at idle peak internal pressure is negligibly small.

Advantageously, the oil separator 26 consists of a plurality of in a manner not shown arranged in the manner of a labyrinth fins 30 extending near one of the drive piston-cylinder unit 8 adjacent the air opening 31, together with filter 27 having wall region of the chamber 28 extend vertically , In the illustrated embodiment the wall section 32 is formed from a narrow side of the chamber 28th The oil separator 26is disposed in a direction perpendicular to the drawing plane, extending and therefore non-visible intermediate wall, which forms within the chamber 28 is a compartment 33, the width of the formed b the axial length of a pot filter 35, the air hole 31 by forming filter 27 equivalent.

Particularly advantageous is the design of which is arranged in the end wall 56 of the drive cylinder 11 Luftan suction valve 17th, this consists in part of a stationary valve plate 35. This valve plate 35 has t from the periphery 36 at a distance along a circle 37 offset through holes 38. Furthermore, an annular valve body 39 is provided, which covers the apertures 38 at the bottom 40 of the valve plate 35th This valve body 39 in the form of a flat ring is held by a spring 41 at the bottom 40 of the valve plate 35 and can be lifted off at reduced pressure in the space 20 of the cylinder 11 against the pressure of spring 41 from the valve plate 35 downward. The spring 41 is a compression coil spring here. The air suction valve 17 operates can be seen as a check valve, but still permits air only into the cylinder 11, not come out.

The purpose of adjusting the passage cross section of the Luftan suction valve 17and hence the air flow rate at a given vacuum in the chamber 20 of the valve is concentrically mounted rotatably and fixed plate 35, an adjustment plate 43 on the outside 42, kon centrally arranged, for example by means of a, in the valve plate 35engage the bolt 44th This adjustment plate 43 has through holes 45, which, the through holes 38 of the valve plate 35 are by means of rotating the adjustment plate 43, either in the opening or in the closing direction for the purpose of continuous changing the passage cross section congruent.

The valve plate 35 is fixed by means of a flange 46 with bolts 47 to the end wall 56or end plate of the cylinder. 

The setting of the air intake valve 17 is performed according to the requirements by loosening the bolt 44, ent speaking twisting of the adjustment 43 in the direction of the double arrow D, depending on whether an increase or a reduction of the passage cross section is desired, and subsequently tightening the bolt 44th It has been found that the described embodiment of the air intake valve 15 and the guaranteed by the same, fine adjustment is particularly meet the ge at an air hammer given needs.