EP0055244B1 - Outil de percussion pneumatique à main - Google Patents

Outil de percussion pneumatique à main Download PDF

Info

Publication number
EP0055244B1
EP0055244B1 EP19810890197 EP81890197A EP0055244B1 EP 0055244 B1 EP0055244 B1 EP 0055244B1 EP 19810890197 EP19810890197 EP 19810890197 EP 81890197 A EP81890197 A EP 81890197A EP 0055244 B1 EP0055244 B1 EP 0055244B1
Authority
EP
European Patent Office
Prior art keywords
piston
ring
tool
hand
air
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.)
Expired
Application number
EP19810890197
Other languages
German (de)
French (fr)
Other versions
EP0055244A1 (en
Inventor
Florian Hasewend
Johann Neumüller
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vereinigte Edelstahlwerke AG
Original Assignee
Vereinigte Edelstahlwerke AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Vereinigte Edelstahlwerke AG filed Critical Vereinigte Edelstahlwerke AG
Publication of EP0055244A1 publication Critical patent/EP0055244A1/en
Application granted granted Critical
Publication of EP0055244B1 publication Critical patent/EP0055244B1/en
Expired legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D9/00—Portable percussive tools with fluid-pressure drive, i.e. driven directly by fluids, e.g. having several percussive tool bits operated simultaneously
    • B25D9/04—Portable percussive tools with fluid-pressure drive, i.e. driven directly by fluids, e.g. having several percussive tool bits operated simultaneously of the hammer piston type, i.e. in which the tool bit or anvil is hit by an impulse member
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D17/00—Details of, or accessories for, portable power-driven percussive tools
    • B25D17/24—Damping the reaction force

Definitions

  • the invention relates to a striking, hand-held compressed air tool, as is used for a wide variety of purposes, for example for the construction industry in general in industry and mining. Demolition hammers are an example of such tools.
  • DE-OS 23 26 087 discloses the use of an O-ring for damping the movement of a striker, which is driven indirectly by an electric motor.
  • a similar damping element is described in DE-OS 25 51 292, where it is arranged between a fixed sleeve of an impacting pneumatic hammer and the housing thereof, which causes the crown to rotate in its up and down movement.
  • the percussion piston in the housing is not damped.
  • DE-AS 10 34 557 describes the use of a rubber buffer ring. which is arranged between the cylinder and the retaining cap of the insertion tool, for buffering both the insertion tool and a stepped piston. In the case of an air-buffered step piston, this rubber buffer ring only serves to dampen the counter-impact of the insert tool.
  • An empty stroke is understood to mean that the impact surface of the accelerated piston does not come into contact with the impact surface of an intermediate piston or the shaft of the working tool.
  • the energy imparted to the piston must be effectively reduced without causing damage or converted into heat.
  • the empty impact energy is usually reduced by air buffers with additional safety precautions.
  • the air buffering of the accelerated piston has been achieved in that it is designed in the form of a piston shaft which can reciprocate in the cylinder of the tool and which has a piston part of smaller diameter, the piston head, on its front side, that is to say in the form of a stepped piston.
  • An annular compression space remains free between the piston head and the inner wall of the cylinder of the tool, which is delimited at one end by the bush for the working tool and at the other end by the step in the step piston.
  • the air cushion located there ensures when the piston moves towards the rear end of the shaft of the actual percussion tool, that is, for. B. the chisel, moves, due to the compression for an effective buffering of the piston.
  • the aim of the invention is to create a striking, hand-held pneumatic tool which does not have the disadvantages mentioned above.
  • the hand-held compressed air tools differ from the others in that they are designed to be relatively small, so that the volume which is used for air buffering is also to be kept small, even with small ones Leaks the air buffering can no longer be effective.
  • the invention is based on the known compressed air tools just described and relates to a striking, hand-held compressed air tool with a tool cylinder, within the bore of which a movable, compressed air-operated, piston piston and piston rod is arranged, which serves to actuate the working tool and to buffer the air, and one Buffer ring and consists essentially in that a buffer ring is arranged in the bore of the tool cylinder, which serves as a sleeve for the piston skirt and by a deformable material, for. B. steel, holding member is held in the bore, which is deformable via the buffer ring by the stepped piston.
  • the kinetic energy of the stepped piston is absorbed by the buffer ring in the event of an empty stroke, which is converted into deformation work and heat in the holding part.
  • the holding part is an interchangeable construction element, through which destruction z. B. the tool cylinder is prevented.
  • a particularly simple construction is realized when a compression space for air buffering is formed by the stepped piston, tool cylinder and buffer ring, and at the same time, if the air buffering is reduced in use by wear of the bore or the piston, a better braking of the piston by simply replacing the buffer ring is available again.
  • the holding part for the buffer ring is provided in a recess in the bore, it can be arranged at any suitable point in the bore, the transmission of the forces from the holding part to the cylinder being able to be solved particularly well by appropriately designing the recesses.
  • the recess is an annular groove, in which a preferably cylindrical retaining ring is arranged, a uniform transmission of the forces from the stepped piston to the tool cylinder can be achieved, even if the stepped piston moves within the tool cylinder with greater play.
  • a structurally particularly space-saving and therefore low-weight solution is obtained if the retaining ring encloses the buffer ring in its entire height.
  • the retaining ring on the side facing the working tool protrudes beyond the buffer ring enclosed by it, particularly gentle buffering of the stepped piston can be achieved, the buffering at the same time having longer distances to reduce the forces.
  • the buffer ring may have slots, so that a particularly simple assembly, for. B. also by inexperienced forces, can be carried out at the construction site.
  • the holding part is made of several parts and consists of individual springs that are arranged in corresponding grooves in the tool cylinder, the piston can be particularly gently buffered, whereby tilting of the buffer ring can be avoided with certainty by a symmetrical arrangement of at least three holding parts .
  • the essential advantage of the compressed air tool according to the invention is that whenever the buffer spring has not been installed on the tool for any reason and / or the piston skirt and / or the piston skirt bore have already been worn and there is therefore an insufficient air buffer, the «soft catch and retaining ring when the piston is badly buffered converts its impact energy into deformation work.
  • the buffer ring moves in the direction of the impact surface of the working tool and, on the one hand, this increases the compression or buffer space, i.e. the air cushion, and on the other hand, due to the shifting of the impact positions between the piston and the working tool (chisel, hammer), rhythm disturbances occur, which make the need for a Make the exchange of the combination of buffer ring and holding part and, if necessary, the piston clearly recognizable.
  • the necessary replacement of parts inferior to wear can be provided in good time without difficulty and the damage described above or even the destruction of the expensive cylinder are practically impossible.
  • the replacement of the wearing parts in the pneumatic tools according to the invention is also relatively simple, and the new tools are particularly customer-friendly and service-friendly.
  • the pneumatic tool shown in FIG. 1 is formed by the cylinder 2, over the end part of which the retaining cap 5 is screwed.
  • the compressed air-operated step piston 1 With the piston shaft 1a and a piston head 1b having a reduced diameter.
  • the piston head 1 b lies with its end face on the end face of the shank of the working tool 8 pressed against it by means of the buffer spring 6, for. B. a chisel.
  • the insertion end or the shank of the tool 8 is guided in the tool sleeve 7.
  • Via the return stroke channel 9 the compressed air for return stroke of the piston is supplied after the work cycle.
  • the annular compression space X for buffering the piston is formed between the piston head 1b and the wall of the bore of the cylinder 2. From the figure it can be clearly seen that the cylinder bore has different diameters at different points and that the recess described above, which represents a dead space, is present at the end of the piston head bore.
  • the compressed air tool according to the invention differs from the previously usual tools, as shown in FIG. 2, in that the piston head 1b of the stepped piston 1 is elongated and in a buffer ring 4, which consists of a holding part or holding ring made of deformable material, usually a metal, preferably soft steel, is enclosed, is guided.
  • the retaining ring can either have a relatively low height 3a and can be pressed into a single-conical ring groove 2a in the cylinder or as a ring with a relatively greater height 3b in a double-conical recess 2b in the cylinder bore with a constant diameter.
  • a compression space X is defined by the end face of the buffer ring 4, the inner wall of the cylinder 2 and the step from the piston skirt to the piston head, which no longer adjoins the end of the shaft of the working tool 8 and the bridge part 7 used to guide the working tool .
  • the air cushion in the compression chamber X effectively buffers the piston.
  • the buffer ring 4 with the retaining ring 3b is made in one piece, the retaining ring part having axial slots, as a result of which the retaining ring can spring together, so that this unit can be assembled easily and quickly.
  • Springs can also be provided as holding parts, which correspond in section to the holding ring 3b or 3a and are arranged in axially aligned grooves, at least 3 grooves having to be evenly distributed around the circumference.
  • the buffer ring 4 is displaced in the direction of the work tool and the retaining or catch ring 3 takes it from Piston 1 exerted energy on the buffer ring with more or less large deformation.
  • the buffer ring is moved in the direction of the insertion end of the working tool, the above-mentioned rhythm disturbances occur, which clearly indicate the wear that occurred before, so that the parts inferior to the wear can be replaced in good time.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Percussive Tools And Related Accessories (AREA)

Description

Die Erfindung betrifft ein schlagendes, handgehaltenes Druckluftwerkzeug, wie es für die verschiedensten Einsatzzwecke, beispielsweise für das Bauwesen ganz allgemein in Industrie und Bergbau Verwendung findet. Als Beispiel für solche Werkzeuge seien Abbruchhämmer genannt.The invention relates to a striking, hand-held compressed air tool, as is used for a wide variety of purposes, for example for the construction industry in general in industry and mining. Demolition hammers are an example of such tools.

Aus der DE-OS 23 26 087 wird die Verwendung eines O-Ringes für die Bewegungsdämpfung eines Döppers bekannt, wobei dieser mittelbar über einen Elektromotor angetrieben wird. Ein ähnliches Dämpfelement wird in der DE-OS 25 51 292 beschrieben, wo es zwischen einer feststehenden Hülse eines schlagend-umsetzenden Druckluftbohrhammers und dem Gehäuse desselben welches in seiner auf- und abführenden Bewegung die Drehung der Krone verursacht, angeordnet ist. Der Schlagkolben im Gehäuse ist jedoch ungedämpft.DE-OS 23 26 087 discloses the use of an O-ring for damping the movement of a striker, which is driven indirectly by an electric motor. A similar damping element is described in DE-OS 25 51 292, where it is arranged between a fixed sleeve of an impacting pneumatic hammer and the housing thereof, which causes the crown to rotate in its up and down movement. However, the percussion piston in the housing is not damped.

Aus der DE-AS 10 34 557 wird die Verwendung eines Pufferringes aus Gummi. welcher zwischen dem Zylinder und der Haltekappe des Einsteckwerkzeuges angeordnet ist, zur Abpufferung sowohl des Einsteckwerkzeuges als auch eines Stufenkolbens bekannt. Bei einem luftgepufferten Stufenkolben dient dieser Pufferring aus Gummi lediglich zur Dämpfung des Gegenschlages des Einsteckwerkzeuges.DE-AS 10 34 557 describes the use of a rubber buffer ring. which is arranged between the cylinder and the retaining cap of the insertion tool, for buffering both the insertion tool and a stepped piston. In the case of an air-buffered step piston, this rubber buffer ring only serves to dampen the counter-impact of the insert tool.

Eines der wesentlichen Kriterien für Haltbarkeit, Lebensdauer und auch Handhabbarkeit solcher druckluftbetriebener Meißel oder Hämmer besteht in der konstruktiven Ausgestaltung der Abpufferung des Kolbens im Zylinder. Die Lösung dieses problems ist besonders bei jenen Druckluftwerkzeugen wichtig, welche hohen Leerschlagbeanspruchungen ausgesetzt sind, wie etwa Meißelhämmer für Baumeisterzwecke und Installateurarbeiten.One of the essential criteria for durability, service life and handling of such air-powered chisels or hammers is the structural design of the piston buffering in the cylinder. The solution to this problem is particularly important for those pneumatic tools that are exposed to high empty impact stresses, such as chisel hammers for building and plumbing purposes.

Die Forderung, die an ein modernes Druckluftwerkzeug gestellt sind, bestehen neben der Einhaltung der ergonomischen Richtlinien und gutem Wirkungsgrad vor allem in einer ausreichenden Leerschlagtauglichkeit der Druckluftwerkzeuge. Unter einem Leerschlag ist zu verstehen, daß die Aufschlagfläche des beschleunigten Kolbens mit der Aufschlagfläche eines Zwischenkolbens oder des Schaftes des Arbeitswerkzeuges nicht in Berührung kommt. Dabei muß aber die dem Kolben verliehene Energie, ohne Schaden anzurichten wirksam abgebaut bzw., in Wärme, umgewandelt werden.In addition to compliance with the ergonomic guidelines and good efficiency, the demands placed on a modern compressed air tool are, above all, that the compressed air tools are sufficiently suitable for empty impact. An empty stroke is understood to mean that the impact surface of the accelerated piston does not come into contact with the impact surface of an intermediate piston or the shaft of the working tool. However, the energy imparted to the piston must be effectively reduced without causing damage or converted into heat.

Der Abbau der Leerschlagenergie erfolgt bei Druckluftwerkzeugen üblicherweise durch Luftabpufferungen mit zusätzlichen Sicherheitsvorkehrungen. Bisher wurde die Luftabpufferung des beschleunigten Kolbens dadurch erreicht, daß dieser in Form eines im Zylinder des Werkzeuges hin- und herbeweglichen Kolbenschaftes ausgebildet ist, der an seiner Vorderseite einen Kolbenteil kleineren Durchmessers, den Kolbenkopf, aufweist, also in Form eines Stufenkolbens ausgebildet ist. Zwischen Kolbenkopf und, Innenwand des Zylinders des Werkzeuges bleibt ein ringförmiger Kompressionsraum frei, der an einem Ende durch die Büchse für das Arbeitswerkzeug und am anderen Ende durch die Stufe im Stufenkolben begrenzt ist. Der dort befindliche Luftpolster sorgt, wenn sich der Kolben in Richtung auf das rückwärtige Ende des Schaftes des eigentlichen Schlagwerkzeuges, also z. B. des Meißels, bewegt, infolge der Kompression für eine wirksame Abpufferung des Kolbens.In the case of compressed air tools, the empty impact energy is usually reduced by air buffers with additional safety precautions. So far, the air buffering of the accelerated piston has been achieved in that it is designed in the form of a piston shaft which can reciprocate in the cylinder of the tool and which has a piston part of smaller diameter, the piston head, on its front side, that is to say in the form of a stepped piston. An annular compression space remains free between the piston head and the inner wall of the cylinder of the tool, which is delimited at one end by the bush for the working tool and at the other end by the step in the step piston. The air cushion located there ensures when the piston moves towards the rear end of the shaft of the actual percussion tool, that is, for. B. the chisel, moves, due to the compression for an effective buffering of the piston.

Zusätzlich zu dieser Luftabpufferung sind weitere Sicherheitsvorkehrungen getroffen, indem z. B. vor dem Bund des Schaftes des Schlagwerkzeuges elastische Teile wie z. B. eine Pufferfeder, Kunststoffteile, Gummischläuche od. dgl. angeordnet werden, so daß insbesondere beim Leerschlag ein metallisches Aufschlagen des Kolbens innerhalb des Zylinders vermieden bzw. abgeschwächt wird.In addition to this air buffering, further safety precautions have been taken, e.g. B. in front of the collar of the shaft of the striking tool elastic parts such. B. a buffer spring, plastic parts, rubber hoses or the like. Arranged so that a metallic impact of the piston within the cylinder is avoided or weakened, especially when empty.

Der Nachteil dieses bisher angewandten Systems besteht insbesondere darin, daß schon bei relativ geringem Verschleiß des Kolbenschaftes die Abpufferung durch den oben genannten Luftpuffer rasch abnimmt. Dadurch wird die Pufferfeder bei längerer Dauer dieses Zustandes überlastet. Bei Verschleiß der Bohrung des Zylinders, in welcher sich der Kolbenschaft bewegt, tritt der gleiche Effekt wie bei Verschleiß des Schaftes ein und wenn beide Teile verschleißen, vervielfacht sich der geschilderte Mangel. Dazu kommt, daß aus fertigungstechnischen Gründen am Ende der Kolbenkopfbohrung ein Einstich gemacht werden muß ; der dadurch vorhandene Totraum hat auf den Luftpuffer ebenfalls einen negativen Einfluß. Wenn ein Verschleiß des Kolbenschaftes eintritt, ist nur der Kolben auszuwechseln, hingegen ist bei Verschleiß der Kolbenschaftbohrung der ganze Zylinder samt der Büchse für das Schlagwerkzeug selbst, also z. B. für den Meißel, auszuwechseln. Bei Bruch der Pufferfeder oder wie in der Praxis gehandhabt, wenn vom Bedienungsmann beim Wechseln des Arbeitswerkzeuges, also z. B. des Meißels, auf den Einbau der Pufferfeder verzichtet wird, schlägt schon nach geringfügigem Verschleiß der eben beschriebenen Teile, Zylinder und/oder Kolbenschaft der Kolben unweigerlich in die Stirnfläche der Brückenbohrung, was letztlich zu einem Querbruch des Zylinders in diesem Bereich führen kann. Schon vor einer derart schweren Beschädigung kann es durch Körperschallübertragung auch zu Sekundärbrüchen im Steuerkörper oder in den Auspuffschellen des Druckluftwerkzeuges kommen.The disadvantage of this previously used system is, in particular, that even with relatively little wear on the piston skirt, the buffering by the air buffer mentioned above decreases rapidly. As a result, the buffer spring is overloaded for a longer period of this state. If the bore of the cylinder in which the piston shaft moves is worn, the same effect occurs as if the shaft is worn, and if both parts wear out, the described defect multiplies. In addition, for technical reasons, a recess must be made at the end of the piston head bore; the resulting dead space also has a negative impact on the air buffer. If the piston skirt becomes worn, only the piston has to be replaced. B. for the chisel. In the event of breakage of the buffer spring or as in practice, when the operator changes the work tool, e.g. B. the chisel, the installation of the buffer spring is dispensed, inevitably beats after slight wear of the parts just described, cylinder and / or piston skirt of the piston in the end face of the bridge bore, which can ultimately lead to a transverse fracture of the cylinder in this area. Even before such severe damage, structure-borne noise transmission can also lead to secondary breaks in the control body or in the exhaust clamps of the compressed air tool.

Ziel der Erfindung ist ein schlagendes, handgehaltenes Druckluftwerkzeug zu schaffen, das die oben angeführten Nachteile nicht aufweist. Die handgehaltenen Druckluftwerkzeuge unterscheiden sich von den übrigen dadurch, daß sie relativ klein ausgestaltet werden, sodaß das Volumen, welches zur Luftabpufferung dient, ebenfalls klein zu halten ist, wobei bereits bei geringen Undichtigkeiten die Luftabpufferung nicht mehr wirksam sein kann.The aim of the invention is to create a striking, hand-held pneumatic tool which does not have the disadvantages mentioned above. The hand-held compressed air tools differ from the others in that they are designed to be relatively small, so that the volume which is used for air buffering is also to be kept small, even with small ones Leaks the air buffering can no longer be effective.

Die Erfindung geht von den eben beschriebenen, bekannten Druckluftwerkzeugen aus und betrifft ein schlagendes, handgehaltenes Druckluftwerkzeug mit einem Werkzeugzylinder innerhalb dessen Bohrung ein beweglicher, druckluftbetriebener, einen Kolbenkopf und einen Kolbenschaft aufweisenden Stufenkolben angeordnet ist, welcher zur Betätigung des Arbeitswerkzeuges und zur Luftabpufferung dient sowie einem Pufferring und besteht im wesentlichen darin, daß ein Pufferring in der Bohrung des Werkzeugzylinders angeordnet ist, welcher als Büchse für den Kolbenschaft dient und durch einen verformbares Material, z. B. Stahl, aufweisenden Halteteil in der Bohrung gehalten ist, der über den Pufferring durch den Stufenkolben deformierbar ist.The invention is based on the known compressed air tools just described and relates to a striking, hand-held compressed air tool with a tool cylinder, within the bore of which a movable, compressed air-operated, piston piston and piston rod is arranged, which serves to actuate the working tool and to buffer the air, and one Buffer ring and consists essentially in that a buffer ring is arranged in the bore of the tool cylinder, which serves as a sleeve for the piston skirt and by a deformable material, for. B. steel, holding member is held in the bore, which is deformable via the buffer ring by the stepped piston.

Durch den Pufferring wird die kinetische Energie des Stufenkolbens bei einem Leerschlag aufgenommen, welche in Verformungsarbeit und Wärme im Halteteil ungewandelt wird. Der Halteteil stellt ein austauschbares Konstruktionselement dar, durch welches eine Zerstörung z. B. des Werkzeugzylinders verhindert wird. Durch die Ausbildung des Pufferringes als Büchse für den Kolbenschaft wird gleichzeitig eine weitere Führung für den Kolben erreicht.The kinetic energy of the stepped piston is absorbed by the buffer ring in the event of an empty stroke, which is converted into deformation work and heat in the holding part. The holding part is an interchangeable construction element, through which destruction z. B. the tool cylinder is prevented. By designing the buffer ring as a sleeve for the piston skirt, further guidance for the piston is achieved at the same time.

Eine besonders einfache Konstruktion ist dann verwirklicht, wenn ein Kompressionsraum zur Luftabpufferung durch Stufenkolben, Werkzeugzylinder und Pufferring gebildet ist, wobei gleichzeitig, falls im Gebrauch die Luftabpufferung durch Abnützung der Bohrung oder des Kolbens herabgemindert ist, durch einfachen Austausch des Pufferringes eine bessere Abbremsung des Kolbens wieder erreichbar ist.A particularly simple construction is realized when a compression space for air buffering is formed by the stepped piston, tool cylinder and buffer ring, and at the same time, if the air buffering is reduced in use by wear of the bore or the piston, a better braking of the piston by simply replacing the buffer ring is available again.

Ist der Halteteil für den Pufferring in einer Ausnehmung der Bohrung vorgesehen, so kann dieser an jeder geeigenten Stelle in der Bohrung angeordnet werden, wobei die Übertragung der Kräfte vom Halteteil zum Zylinder durch entsprechende Ausgestaltung der Ausnehmungen besonders gut gelöst werden kann.If the holding part for the buffer ring is provided in a recess in the bore, it can be arranged at any suitable point in the bore, the transmission of the forces from the holding part to the cylinder being able to be solved particularly well by appropriately designing the recesses.

Ist die Ausnehmung eine Ringnut, in welcher ein vorzugsweise zylindrischer Haltering angeordnet ist, kann eine gleichmäßige Übertragung der Kräfte vom Stufenkolben auf den Werkzeugzylinder erreicht werden, selbst wenn der Stufenkolben sich mit einem größeren Spiel innerhalb des Werkzeugzylinders bewegt.If the recess is an annular groove, in which a preferably cylindrical retaining ring is arranged, a uniform transmission of the forces from the stepped piston to the tool cylinder can be achieved, even if the stepped piston moves within the tool cylinder with greater play.

Eine konstruktiv besonders platzsparende und damit gewichtsarme Lösung ergibt sich dann, wenn der Haltering in seiner gesamten Höhe den Pufferring umschließt.A structurally particularly space-saving and therefore low-weight solution is obtained if the retaining ring encloses the buffer ring in its entire height.

Ragt der Haltering an der dem Arbeitswerkzeug zugekehrten Seite über den von ihm umschlossenen Pufferring heraus, so kann eine besonders schonende Abpufferung des Stufenkolbens erreicht werden, wobei gleichzeitig die Abpufferung längere Strecken zum Abbau der Kräfte aufweist.If the retaining ring on the side facing the working tool protrudes beyond the buffer ring enclosed by it, particularly gentle buffering of the stepped piston can be achieved, the buffering at the same time having longer distances to reduce the forces.

Eine besonders einfache Konstruktion ergibt sich dann, wenn der Haltering gemeinsam mit dem Pufferring aus einem Stück besteht, wobei der Pufferring Schlitze aufweisen kann, sodaß eine besonders einfache Montage, z. B. auch von ungeübten Kräften, an der Baustelle durchgeführt werden kann.A particularly simple construction results when the retaining ring together with the buffer ring consists of one piece, the buffer ring may have slots, so that a particularly simple assembly, for. B. also by inexperienced forces, can be carried out at the construction site.

Ist der Halteteil mehrteilig ausgebildet und besteht er aus einzelnen Federn, die in entsprechenden Nuten im Werkzeugzylinder angeordnet sind, so kann eine besonders schonende Abpufferung des Kolbens erreicht werden, wobei durch eine symmetrische Anordnung von zumindest drei Halteteilen ein Verkanten des Pufferringes mit Sicherheit vermieden werden kann.If the holding part is made of several parts and consists of individual springs that are arranged in corresponding grooves in the tool cylinder, the piston can be particularly gently buffered, whereby tilting of the buffer ring can be avoided with certainty by a symmetrical arrangement of at least three holding parts .

Eine fertigungstechnisch besonders einfache und trotzdem hochwirksame Konstruktion ergibt sich dann, wenn die Bohrung des Zylinders einen konstanten Durchmesser aufweist und darin der Pufferring und die Büchse zur Führung des Einsteckendes des Arbeitswerkzeuges angeordnet sind.A construction that is particularly simple in terms of production technology, but nevertheless highly effective, results when the bore of the cylinder has a constant diameter and the buffer ring and the bushing for guiding the insertion end of the working tool are arranged therein.

Der wesentliche Vorteil des erfindungsgemäßen Druckluftwerkzeuges besteht darin, daß immer dann, wenn aus irgendwelchen Gründen der Einbau der Pufferfeder am Werkzeug nicht erfolgt ist und/oder es bereits zu einem Verschleiß des Kolbenschaftes und/oder der Kolbenschaftbohrung gekommen ist und daher ein ungenügender Luftpuffer vorliegt, der « weiche Fang- und Haltering beim schlecht abgepufferten Aufschlagen des Kolbens dessen Schlagenergie in Verformungsarbeit umwandelt. Dabei wandert der Pufferring in Richtung Aufschlagfläche des Arbeitswerkzeuges und es vergrößert sich hierdurch einerseits der Kompressions- oder Pufferraum, also der Luftpolster, und andererseits kommt es infolge der Verlagerung der Aufschlaglagen zwischen Kolben und Arbeitswerkzeug (Meißel, Hammer) zu Rhythmusstörungen, die die Notwendigkeit eines Austausches der Kombination von Pufferring und Halteteil und allenfalls des Kolbens deutlich erkennbar machen. Dadurch kann ohne Schwierigkeiten rechtzeitig für den nötigen Austausch von dem Verschleiß unterlegenen Teilen gesorgt werden und die oben beschriebenen Beschädigungen oder gar die Zerstörungen des teuren Zylinders sind praktisch ausgeschlossen.The essential advantage of the compressed air tool according to the invention is that whenever the buffer spring has not been installed on the tool for any reason and / or the piston skirt and / or the piston skirt bore have already been worn and there is therefore an insufficient air buffer, the «soft catch and retaining ring when the piston is badly buffered converts its impact energy into deformation work. The buffer ring moves in the direction of the impact surface of the working tool and, on the one hand, this increases the compression or buffer space, i.e. the air cushion, and on the other hand, due to the shifting of the impact positions between the piston and the working tool (chisel, hammer), rhythm disturbances occur, which make the need for a Make the exchange of the combination of buffer ring and holding part and, if necessary, the piston clearly recognizable. As a result, the necessary replacement of parts inferior to wear can be provided in good time without difficulty and the damage described above or even the destruction of the expensive cylinder are practically impossible.

Infolge der vereinfachten Konstruktion ist das Auswechseln der Verschleißteile bei den erfindungsgemäßen Druckluftwerkzeugen ebenfalls relativ einfach, die neuen Werkzeuge zeichnen sich besonders durch Kunden- und Servicefreundlichkeit aus.As a result of the simplified construction, the replacement of the wearing parts in the pneumatic tools according to the invention is also relatively simple, and the new tools are particularly customer-friendly and service-friendly.

An Hand der Zeichnung wird die Erfindung näher erläutert.The invention is explained in more detail with reference to the drawing.

Es zeigen :

  • Figur 1 einen schematischen Längsschnitt durch ein bisher gebräuchliches Druckluftwerkzeug und
  • Figur 2 einen Längsschnitt durch ein erfindungsgemäßes Druckluftwerkzeug.
Show it :
  • 1 shows a schematic longitudinal section through a previously used pneumatic tool and
  • Figure 2 shows a longitudinal section through an air tool according to the invention.

Das in Fig. 1 dargestellte Druckluftwerkzeug ist gebildet durch den Zylinder 2, über dessen Endteil die Haltekappe 5 geschraubt ist. Innerhalb des Zylinders 2 bewegt sich der druckluftbetriebene Stufenkolben 1 mit dem Kolbenschaft 1a und einem verringertem Durchmesser aufweisenden Kolbenkopf 1 b. Der Kolbenkopf 1 b liegt mit seiner Endfläche an der Endfläche des mittels der Pufferfeder 6 gegen ihn gedrückten Schaftes des Arbeitswerkzeuges 8, z. B. eines Meißels, an. Das Einsteckende bzw. der Schaft des Werkzeuges 8 ist in der Werkzeugbüchse 7 geführt. Über den Rückhubkanal 9 wird die Druckluft zum Rückhub des Kolbens nach dem Arbeitstakt zugeführt. Zwischen Kolbenkopf 1b und Wand der Bohrung des Zylinders 2 ist der ringförmige Kompressionsraum X zur Abpufferung des Kolbens ausgebildet. Aus der Figur ist deutlich zu erkennen, daß die Zylinderbohrung an verschiedenen Stellen unterschiedliche Durchmesser aufweist, und daß am Ende der Kolbenkopfbohrung der oben beschriebene Einstich, der einen Totraum darstellt, vorhanden ist.The pneumatic tool shown in FIG. 1 is formed by the cylinder 2, over the end part of which the retaining cap 5 is screwed. Within the Cylinder 2 moves the compressed air-operated step piston 1 with the piston shaft 1a and a piston head 1b having a reduced diameter. The piston head 1 b lies with its end face on the end face of the shank of the working tool 8 pressed against it by means of the buffer spring 6, for. B. a chisel. The insertion end or the shank of the tool 8 is guided in the tool sleeve 7. Via the return stroke channel 9, the compressed air for return stroke of the piston is supplied after the work cycle. The annular compression space X for buffering the piston is formed between the piston head 1b and the wall of the bore of the cylinder 2. From the figure it can be clearly seen that the cylinder bore has different diameters at different points and that the recess described above, which represents a dead space, is present at the end of the piston head bore.

Das erfindungsgemäße Druckluftwerkzeug unterscheidet sich von den bisher üblichen Werkzeugen, wie Fig. 2 zeigt, dadurch, daß der Kolbenkopf 1b des Stufenkolbens 1 verlängert ausgebildet und in einem Pufferring 4, der von einem Halteteil oder Haltering aus verformbarem Material, meist einem Metall, vorzugsweise aus weichem Stahl, umschlossen ist, geführt ist. Der Haltering kann entweder relativ geringe Höhe 3a aufweisen und in einer einfach-konischen Ringnut 2a im Zylinder oder als Ring mit relativ größerer Höhe 3b in einem doppelt-konischen Einstich 2b in der Zylinderbohrung mit konstantem Durchmesser eingepreßt sein. Es wird dabei ein von der Stirnfläche des Pufferringes 4, der Innenwand des Zylinders 2 und der Stufe vom Kolbenschaft zum Kolbenkopf hin begrenzter Kompressionsraum X ausgebildet, der nicht mehr an das Ende des Schaftes des Arbeitswerkzeuges 8 und den zur Führung des Arbeitswerkzeuges dienenden Brückenteil 7 angrenzt. Der im Kompressionsraum X befindliche Luftpolster bewirkt eine wirksame Abpufferung des Kolbens.The compressed air tool according to the invention differs from the previously usual tools, as shown in FIG. 2, in that the piston head 1b of the stepped piston 1 is elongated and in a buffer ring 4, which consists of a holding part or holding ring made of deformable material, usually a metal, preferably soft steel, is enclosed, is guided. The retaining ring can either have a relatively low height 3a and can be pressed into a single-conical ring groove 2a in the cylinder or as a ring with a relatively greater height 3b in a double-conical recess 2b in the cylinder bore with a constant diameter. A compression space X is defined by the end face of the buffer ring 4, the inner wall of the cylinder 2 and the step from the piston skirt to the piston head, which no longer adjoins the end of the shaft of the working tool 8 and the bridge part 7 used to guide the working tool . The air cushion in the compression chamber X effectively buffers the piston.

Es besteht auch die Möglichkeit, daß der Pufferring 4 mit dem Haltering 3b aus einem Stück besteht, wobei der Halteringteil axiale Schlitze aufweist, wodurch der Haltering zusammenfedern kann, sodaß eine leichte und schnelle Montage dieser Einheit möglich ist.There is also the possibility that the buffer ring 4 with the retaining ring 3b is made in one piece, the retaining ring part having axial slots, as a result of which the retaining ring can spring together, so that this unit can be assembled easily and quickly.

Als Halteteile können auch Federn vorgesehen werden, die im Schnitt dem Haltering 3b oder 3a entsprechen und in axial ausgerichteten Nuten angeordnet sind, wobei zumindest 3 Nuten um den Umfang gleichmäßig verteilt sein müssen.Springs can also be provided as holding parts, which correspond in section to the holding ring 3b or 3a and are arranged in axially aligned grooves, at least 3 grooves having to be evenly distributed around the circumference.

Wenn infolge Verschleißes von Kolbenschaft 1a und/oder Bohrung die Abpufferung nicht mehr voll wirksam ist und der Kolben mit steigendem Verschleiß immer weiter gegen das Arbeitswerkzeug 8 beschleunigt wird, wird der Pufferring 4 in Richtung Arbeitswerkzeug verschoben und der Halte- oder Fangring 3 nimmt die vom Kolben 1 auf den Pufferring ausgeübte Energie unter mehr oder minder großer Verformung auf. Bei der Verschiebung des Pufferringes in Richtung Einsteckende des Arbeitswerkzeuges kommt es zu den oben erwähnten Rhythmusstörungen, welche den vorher erfolgten Verschleiß deutlich anzeigen, so daß rechtzeitig der Austausch der dem Verschleiß unterlegenen Teile erfolgen kann.If, due to wear of the piston skirt 1a and / or bore, the buffering is no longer fully effective and the piston is accelerated with increasing wear against the work tool 8, the buffer ring 4 is displaced in the direction of the work tool and the retaining or catch ring 3 takes it from Piston 1 exerted energy on the buffer ring with more or less large deformation. When the buffer ring is moved in the direction of the insertion end of the working tool, the above-mentioned rhythm disturbances occur, which clearly indicate the wear that occurred before, so that the parts inferior to the wear can be replaced in good time.

Claims (9)

1. A percussive, hand-held compressed-air tool, with a tool cylinder (2) inside whose bore a movable pneumatically operated differential piston (1) is disposed which comprises a piston head (1 b) and a piston body (1 a) and used for actuating the operating tool and for air cushioning, and with a cushioning ring (4), characterized in that the cushioning ring (4) is disposed in the bore of the tool cylinder (2), acts as a bush for the piston body, and is held in the bore by a retaining member (3a, 3b) which is of deformable material, for example steel, and which is deformable by the differential piston by way of the cushioning ring (4).
2. A percussive, hand-held compressed-air tool according to claim 1, characterized in that a compression space (X) for air cushioning is formed by the differential piston, the tool cylinder, and the cushioning ring (4).
3. A percussive, hand-held compressed-air tool according to claim 1 or 2, characterized in that the retaining member (3a, 3b) for the cushioning ring (4) is provided in a recess in the bore.
4. A percussive, hand-held compressed-air tool according to claim 1, 2, or 3, characterized in that the recess is an annular groove (2a, 2b) in which a preferably cylindrical retaining ring (3a, 3b) is disposed.
5. A percussive, hand-held compressed-air tool according to any one of claims 1 to 4, characterized in that the retaining ring (3a) surrounds the cushioning ring (4) over its entire height.
6. A percussive, hand-held compressed-air tool according to any one of claims 1 to 4, characterized in that on the side facing the operating tool the retaining ring (3b) projects beyond the cushioning ring surrounded thereby.
7. A percussive, hand-held compressed-air tool according to any one of claims 1 to 6, characterized in that the retaining ring is made integrally in one piece together with the cushioning ring.
8. A percussive, hand-held compressed-air tool according to any one of claims 1, 2 or 3, characterized in that the retaining members are constructed in the form of springs which are disposed in corresponding grooves in the tool cylinder.
9. A percussive, hand-held compressed-air tool according to any one of claims 1 to 8, characterized in that the bore of the cylinder (2) has a constant diameter and the cushioning ring (4) and the bush (7) for guiding the shank of the operating tool (8) are disposed therein.
EP19810890197 1980-12-19 1981-12-09 Outil de percussion pneumatique à main Expired EP0055244B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AT6201/80 1980-12-19
AT620180A AT368801B (en) 1980-12-19 1980-12-19 STRIKING, HAND-HOLDED AIR TOOL

Publications (2)

Publication Number Publication Date
EP0055244A1 EP0055244A1 (en) 1982-06-30
EP0055244B1 true EP0055244B1 (en) 1985-04-24

Family

ID=3583921

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19810890197 Expired EP0055244B1 (en) 1980-12-19 1981-12-09 Outil de percussion pneumatique à main

Country Status (5)

Country Link
EP (1) EP0055244B1 (en)
AT (1) AT368801B (en)
CS (1) CS254308B2 (en)
DD (1) DD208106A5 (en)
DE (1) DE3170203D1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7726413B2 (en) 2006-07-01 2010-06-01 Black & Decker Inc. Tool holder for a powered hammer
US7814986B2 (en) 2006-07-01 2010-10-19 Balck & Decker Inc. Lubricant system for powered hammer
US8590633B2 (en) 2006-07-01 2013-11-26 Black & Decker Inc. Beat piece wear indicator for powered hammer
RU2790125C1 (en) * 2022-07-18 2023-02-14 Федеральное государственное бюджетное образовательное учреждение высшего образования Новосибирский государственный архитектурно-строительный университет (Сибстрин) Pneumatic hammer

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE444401B (en) * 1983-01-24 1986-04-14 Atlas Copco Ab ENERGY ABSORBING POCKET UNIT RECORDING UNIT
DE3309187A1 (en) * 1983-03-15 1984-09-20 Robert Bosch Gmbh, 7000 Stuttgart HAMMER, ESPECIALLY DRILLING HAMMER
DE3405980A1 (en) * 1984-02-18 1985-08-22 Günter Horst 7927 Sontheim Röhm IMPACT DRILLING DEVICE
JPS61148580U (en) * 1985-03-01 1986-09-12

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE332236A (en) *
DE1034557B (en) * 1954-11-12 1958-07-17 Hauhinco Maschf Jackhammer
DE1033148B (en) * 1956-10-03 1958-06-26 Eisen & Stahlind Ag Compressed air impact tool with an elastic buffer ring arranged between the lower cylinder bridge and the impact piston
DE6809332U (en) * 1968-11-30 1969-08-07 Bosch R Gmbh MOTOR DRIVEN PORTABLE DRILL HAMMER
DE2023913B2 (en) * 1970-05-15 1978-11-02 Hilti Ag, Schaan (Liechtenstein) Electropneumatic hammer drill
DE2351242A1 (en) * 1973-10-12 1975-04-17 Bosch Gmbh Robert MOTOR-DRIVEN HAMMER WITH AIR SUSPENSION
DE2437023A1 (en) * 1974-08-01 1976-02-12 Duss Maschf STRIKING OR ROTARY HAMMER
DE2743155A1 (en) * 1977-09-24 1979-04-05 Impex Essen Vertrieb Oscillating air operated hammer - has arresting spiral spring coiled from square cross=section wire contained in housing around tool impact area
DE2756993A1 (en) * 1977-12-21 1979-07-05 Duss Maschf ELECTROPNEUMATIC HAMMER WITH CATCH RING FOR THE PISTON

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7726413B2 (en) 2006-07-01 2010-06-01 Black & Decker Inc. Tool holder for a powered hammer
US7814986B2 (en) 2006-07-01 2010-10-19 Balck & Decker Inc. Lubricant system for powered hammer
US8590633B2 (en) 2006-07-01 2013-11-26 Black & Decker Inc. Beat piece wear indicator for powered hammer
RU2790123C1 (en) * 2022-07-11 2023-02-14 Федеральное государственное бюджетное образовательное учреждение высшего образования Новосибирский государственный архитектурно-строительный университет (Сибстрин) Pneumatic hammer
RU2789977C1 (en) * 2022-07-11 2023-02-14 Федеральное государственное бюджетное образовательное учреждение высшего образования Новосибирский государственный архитектурно-строительный университет (Сибстрин) Pneumatic hammer
RU2790125C1 (en) * 2022-07-18 2023-02-14 Федеральное государственное бюджетное образовательное учреждение высшего образования Новосибирский государственный архитектурно-строительный университет (Сибстрин) Pneumatic hammer
RU2790852C1 (en) * 2022-07-18 2023-02-28 Федеральное государственное бюджетное образовательное учреждение высшего образования Новосибирский государственный архитектурно-строительный университет (Сибстрин) Pneumatic hammer
RU2793242C1 (en) * 2022-07-18 2023-03-30 Федеральное государственное бюджетное образовательное учреждение высшего образования Новосибирский государственный архитектурно-строительный университет (Сибстрин) Pneumatic hammer
RU2796480C1 (en) * 2022-07-18 2023-05-24 Федеральное государственное бюджетное образовательное учреждение высшего образования Новосибирский государственный архитектурно-строительный университет (Сибстрин) Pneumatic hammer
RU2796481C1 (en) * 2022-07-18 2023-05-24 Федеральное государственное бюджетное образовательное учреждение высшего образования Новосибирский государственный архитектурно-строительный университет (Сибстрин) Pneumatic hammer
RU2799469C1 (en) * 2022-07-18 2023-07-05 Федеральное государственное бюджетное образовательное учреждение высшего образования Новосибирский государственный архитектурно-строительный университет (Сибстрин) Pneumatic hammer

Also Published As

Publication number Publication date
CS254308B2 (en) 1988-01-15
DD208106A5 (en) 1984-03-28
EP0055244A1 (en) 1982-06-30
ATA620180A (en) 1982-03-15
DE3170203D1 (en) 1985-05-30
AT368801B (en) 1982-11-10

Similar Documents

Publication Publication Date Title
EP0066779B1 (en) Boring or chiseling hammer
DE19815650B4 (en) rotary hammer
EP0055244B1 (en) Outil de percussion pneumatique à main
CH643176A5 (en) HAND TOOLING MACHINE, ESPECIALLY CHISEL HAMMER.
EP3083155A1 (en) Handheld power tool
EP1781426B1 (en) Needle gun
EP4058252A1 (en) Striking mechanism assembly
DE19929183B4 (en) Air spring hammer mechanism with hollow impact piston with idle opening
EP1910039A1 (en) Percussion mechanism and at least percussively-operated hand machine tool with a percussion mechanism
EP0663270B1 (en) Impact hammer with rotative and/or percussive action
EP1340596B1 (en) Pneumatic percussion mechanism
EP3140081A1 (en) Hand-held power tool
DE2726214A1 (en) Rotary and impact drill with pneumatic piston - has buffer and seal with braking action, between piston and impact member
EP3450109B1 (en) Hammer device, preferably hand-held hammer device
DE2605998C3 (en) Rotary hammer with drive and impact elements housed in a cylinder
EP0312831B1 (en) Vibration isolator for a pneumatic chiselling hammer
EP4058251B1 (en) Impact device assembly
DE810498C (en) Electric hammer
DE19607329C2 (en) Mechanism for preventing idle shocks in power striking tools
DE3231902C2 (en)
DE3421825A1 (en) Vibration reduction by means of variable applied pressure in compressed-air hammers
CH560587A5 (en) Mounting for portable motor driven hammer - has housing and adjustable tool with spring between hammer and tool
WO2020126499A1 (en) Hand-held power tool
DE894530C (en) Jackhammer with device for shock absorption
DE1944018B2 (en) Hammer powered by compressed air

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): CH DE FR GB IT NL SE

17P Request for examination filed

Effective date: 19821220

ITF It: translation for a ep patent filed
GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): CH DE FR GB IT LI NL SE

REF Corresponds to:

Ref document number: 3170203

Country of ref document: DE

Date of ref document: 19850530

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19891116

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19891118

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19891120

Year of fee payment: 9

Ref country code: CH

Payment date: 19891120

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19891130

Year of fee payment: 9

ITTA It: last paid annual fee
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19891231

Year of fee payment: 9

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19901209

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19901210

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Effective date: 19901231

Ref country code: CH

Effective date: 19901231

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19910701

GBPC Gb: european patent ceased through non-payment of renewal fee
NLV4 Nl: lapsed or anulled due to non-payment of the annual fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19910830

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19910903

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

EUG Se: european patent has lapsed

Ref document number: 81890197.7

Effective date: 19910910