EP3184252A1 - Combustion-driven setting tool and method for operating such a setting tool - Google Patents

Abstract

The invention relates to a combustion-actuated setting tool (1) for driving fasteners into a substrate, having at least one main combustion chamber (6) for a fuel, with a driving piston (10) which can be guided via ex-positionable gases from the main combustion chamber (6) in the setting direction (15). is drivable, and with an antechamber (25), which is associated with an ignition device (26) and in which prior to the ignition of a fuel-air mixture in the main combustion chamber (6) on the main combustion chamber (6) acting pressure is buildable, the prechamber (25) is connected or connectable to an environment of the prechamber (25) via at least one passage opening (31, 32), which can be closed by a control device (30). In order to improve the effectiveness and / or the functionality when driving in fasteners, the control device (30) comprises an electronic controller (100).

Description

Technical area

The invention relates to a combustion-powered setting tool for driving fasteners into a substrate, with at least one main combustion chamber for a fuel, with a driving piston, which is drivable by exandierbare gases from the main combustion chamber in the setting direction, and with an antechamber, which is associated with an ignition and in in front of the ignition of a fuel-air mixture in the main combustion chamber, a pressure acting on the main combustion chamber pressure is buildable, wherein the prechamber via at least one passage opening which is closable by a control device, connected to an environment of the prechamber or is connectable. The invention further relates to a method for operating such a combustion-powered setting tool.

State of the art

From the German patent application DE 10 32 035 A1 a combustion-powered setting tool for driving fasteners into a substrate is known, comprising at least one main combustion chamber for a fuel, with a piston mounted in a piston guide drive piston, which is driven by expanding gases from the main combustion chamber in the setting direction, and with a prechamber, in front of the Ignition of a fuel-air mixture in the main combustion chamber, a pressure acting on the main combustion chamber pressure is buildable, wherein the pre-chamber of a remote from the main combustion chamber bottom of the drive piston located in its initial position subsequent space is formed within the piston guide, and wherein the pre-chamber via a Passage with the main combustion chamber at least temporarily in communication, wherein in the main combustion chamber, a means for detecting the pressure is provided, which cooperates with the ignition device for the main combustion chamber.

Presentation of the invention

The object of the invention is the effectiveness and / or functionality when driving fasteners with a combustion-powered setting tool with at least one main combustion chamber for a fuel, with a driving piston which is drivable via exansparable gases from the main combustion chamber in the setting direction, and with an antechamber, an ignition device is assigned and in the prior to the ignition of a fuel-air mixture in the main combustion chamber acting on the main combustion pressure can be built up, the pre-chamber via at least one passage opening which is closed by a control device connected to an environment of the prechamber or connectable, to improve.

The object is with a combustion-powered setting tool for driving fasteners into a substrate, with at least one main combustion chamber for a fuel, with a driving piston which is drivable via exandierbare gases from the main combustion chamber in the setting direction, and with an antechamber, which is associated with an ignition and in which prior to the ignition of a fuel-air mixture in the main combustion chamber, a pressure acting on the main combustion chamber pressure is buildable, the prechamber via at least one passage opening which is closed by a control device, connected to an environment of the pre-chamber or connected, thereby achieved in that the control device comprises an electronic control. By using the electronic control for closing or releasing the passage opening of the antechamber, undesired friction losses during operation of the combustion-powered setting device can be significantly reduced. As a result, the life of the combustion-powered setting device can be extended.

A preferred embodiment of the combustion-powered setting tool is characterized in that the electronic control is connected to an electric actuator. About the electric actuator, the passage opening of the pre-chamber can be quickly closed or released in a simple manner.

Another preferred embodiment of the combustion-powered setting tool is characterized in that the electric actuator comprises an electric motor. The electric motor can be controlled quickly and easily via the electronic control. To illustrate the electric actuator, the electric motor is mounted, for example, on the outside of a housing, in particular an antechamber cylinder.

A further preferred embodiment of the combustion-powered setting tool is characterized in that the electrical actuator is mechanically coupled to a control sleeve. The mechanical coupling between the electric actuator and the control sleeve includes, for example, a kind of transmission. The control sleeve has, for example, substantially the shape of a straight circular cylinder jacket which relative to the housing, in particular the prechamber cylinder which delimits the prechamber, between an open position in which the passage opening of the prechamber is released or opened, and a closed position which is the passage opening of the antechamber is released, is movable.

A further preferred embodiment of the combustion-powered setting tool is characterized in that the control sleeve has a toothing which is coupled via a gear with the electric actuator. The toothing may for example be provided on a toothed rack, which is fastened to the outside of the control sleeve. The gear meshes advantageous with the teeth of the rack. As a result, a kind of transmission is shown in a simple manner, via which the control sleeve can be moved by the electric motor controlled by the electronic control.

A further preferred embodiment of the combustion-powered setting tool is characterized in that the control sleeve is designed and movable relative to the passage opening of the antechamber, that the passage opening of the pre-chamber is released or closed by the electronic control by the electric actuator of the control sleeve. The movement of the control sleeve between the open position and the closed position is made possible for example by a guide of the control sleeve on the housing or the antechamber cylinder, which limits the antechamber. With a complete overlap between a passage opening in the control sleeve and the passage opening of the prechamber, a passage cross section or outlet cross section of the prechamber is maximum. In the closed position, the passage opening of the antechamber is preferably completely closed by the control sleeve. About the electronic control can easily and manner any intermediate positions of the control sleeve can be displayed. Thus, the passage cross-section with the aid of the electronic control and the electric actuator between the open position and the closed position can be varied continuously. As a result, an energy adjustment or adjustment during operation of the setting device is made possible in a particularly advantageous manner.

A further preferred embodiment of the combustion-powered setting tool is characterized in that the electronic control is connected to at least one sensor device which is associated with the main combustion chamber. The sensor device is, for example, a pressure sensor which detects a pressure in the main combustion chamber. A signal from the pressure sensor is processed in the electronic controller of the controller. The sensor device may comprise further sensors which detect, for example, an ambient pressure, a pressure in the pre-chamber, an acceleration of the setting device and / or a temperature at any point of the setting device.

According to a further embodiment, the electronic control of the control device may comprise a user interface. A user of the setting device can individually change or adjust an energy setting of the setting device via the user point.

Another preferred embodiment of the combustion-powered setting tool is characterized in that the electronic control is connected to the ignition device, which is assigned to the prechamber. As a result, temporal sequence control during operation of the combustion-powered setting device is made possible in a simple manner. The opening and closing of the passage opening of the pre-chamber can be timed after a certain period of time after an antechamber ignition. For this purpose, a time interval is measured in the electronic control of the control device, for example, which begins with the prechamber ignition. After the previously set time interval can then be activated automatically, also via the electronic control, the electric actuator for opening the passage opening of the antechamber by means of the control sleeve.

A further preferred embodiment of the combustion-powered setting tool is characterized in that the main combustion chamber is associated with a further ignition device. The setting device described above can with only one ignition device operated, which is assigned to the antechamber. After ignition in the prechamber, reaction gases from the prechamber spread into the main combustion chamber with a progressing flame front. About the propagating into the main combustion chamber flame front then takes place in the main combustion chamber, the ignition of a precompressed air-fuel mixture contained there. The ignition of the fuel-air mixture in the main combustion chamber can also take place via the further ignition device in the main combustion chamber.

In a method for operating a combustion-operated setting tool described above, the above-mentioned object is alternatively or additionally achieved in that the control of the passage opening of the antechamber is effected by the main combustion chamber pressure. This can be realized in a simple manner, a combustion-powered or gas-powered setting tool, which has a much higher energy density. By the measures described above, the control of a venting of the pre-chamber can be realized particularly easily. In this case, an undesirable wear during operation of the setting device can be reduced particularly advantageous. In addition, can be ensured by the control of the passage opening of the prechamber by the main combustion chamber pressure a significantly increased life of the setting device.

A preferred embodiment of the method is characterized in that the control of the passage opening of the antechamber is ignition time-dependent and / or sensor-dependent. As a result, the control of a pre-chamber vent in the operation of the combustion-powered setting device can be realized in a simple manner.

If appropriate, the invention also relates to a computer program product with a program code for carrying out a method described above, in particular if the program is executed in the control of the setting device.

The invention further relates to a control device, in particular an electronic control, an electric actuator and / or a control sleeve for a previously described setting tool. The parts mentioned may be traded separately.

• Figur 1 eine vereinfachte Darstellung eines brennkraftbetriebenen Setzgeräts mit einer Steuereinrichtung vor einer Zündung in einer Vorkammer im Längsschnitt und
• Figur 2 ein ähnliches Setzgerät wie in Figur 1 mit einer anderen Steuereinrichtung kurz vor einer Zündung in einer Vorkammer im Längsschnitt.

Further advantages, features and details of the invention will become apparent from the following description in which, with reference to the drawings, various embodiments are described in detail. Show it:

• FIG. 1 a simplified representation of a combustion-powered setting tool with a control device before ignition in an antechamber in longitudinal section and
• FIG. 2 a similar setting device as in FIG. 1 with a different control device shortly before ignition in an antechamber in longitudinal section.

embodiments

In the FIGS. 1 and 2 is a setting tool 1 greatly simplified in a longitudinal section shown in various operating conditions. That in the FIGS. 1 and 2 Setting device 1 shown can be operated with a fuel gas or with a vaporizable liquid fuel. The setting device 1 comprises a housing 3 with a master cylinder 5, which limits a main combustion chamber 6. The main combustion chamber 6 can be supplied via an inlet device 8 gas and / or air.

In the housing 3 of the setting device 1 is a driving piston 10 in the FIGS. 1 and 2 moved back and forth down and up. The driving piston 10 comprises a piston rod 11, which starts from a piston head 12. A facing away from the piston head 12 setting end 14 of the piston rod 11 is arranged in a (not shown) bolt guide, which serves to guide fasteners, which are also referred to as bolts.

The bolt guide with the piston rod 11 of the drive piston 10 disposed therein is also referred to as a setter. About the network, a fastener, such as a nail, bolts or the like, are driven into a (not shown) underground. Before setting a fastener, the setting tool 1 is pressed with his pin guide to the ground and triggered. To trigger a setting process, for example, a switch (not shown) is used, which is also called a trigger switch. The switch is provided, for example, on a (also not shown) handle of the setting device 1.

By an arrow 15 is in the FIGS. 1 and 2 a setting direction indicated. When setting a fastener of the driving piston 10 is strongly accelerated with the piston rod 11 in the setting direction 15 to drive the fastener into the ground. During the setting process, the driving piston 10 from his in the FIGS. 1 and 2 shown starting position, which corresponds to a top dead center, moved to an end position corresponding to a bottom dead center.

A movement of the driving piston 10 in the FIGS. 1 and 2 upwards is limited by a cylinder-fixed piston stop 16. By the piston stop 16, the top dead center of the driving piston 10 is defined. The piston stop 16 may be combined with a magnetic device 17. The magnetic device 17 is used, for example, the driving piston 10 with a predetermined holding force in his in the FIGS. 1 and 2 to keep the initial position shown.

Movement of the drive piston 10 downwards is limited by one or more stop and / or damping elements 28, 29. The stop and / or damping elements 28 are designed, for example, as a buffer.

The piston head 12 comprises a first piston surface 21, which faces the main combustion chamber 6. A second piston surface 22, which faces away from the main combustion chamber 6, delimits an antechamber 25 in an antechamber cylinder 24. The prechamber cylinder 24 is part of the housing 3 of the setting device 1.

The prechamber 25 represents a pre-combustion chamber to which an ignition device 26 and an inlet device 27 are assigned. In addition, the stop and / or damping elements 28, 29 are arranged in the antechamber 25. About the inlet device 27 of the pre-chamber or pre-combustion chamber 25, a fuel gas-air mixture is supplied, which is ignited by means of the ignition device 26 in the pre-chamber 25.

The pre-chamber cylinder 24 comprises two passage openings 31, 32, which allow, for example, the exit of exhaust gases from the pre-chamber 25. The passage openings 31, 32 can be closed by a control device 30 as needed. The control device 30 comprises a control sleeve 34, which has two passage openings 37, 38.

If the passage openings 37, 38 of the control sleeve 34 are brought into register with the passage openings 31, 32, then the passage openings 31, 32 are opened. In the FIGS. 1 and 2 the passage openings 31, 32 are closed by the control sleeve 34. The control sleeve 34 has substantially the shape of a straight circular cylinder jacket and is in the FIGS. 1 and 2 movable downwards and upwards.

Between the antechamber 25 and the main combustion chamber 6, two or more overflow openings 41, 42 are provided. The overflow openings 41, 42 are each assigned a valve device 43, 44. The valve devices 43, 44 are, for example, valve flaps which open in a pressure-dependent manner in order to allow passage of the ignited air-fuel mixture from the prechamber 25 into the main combustion chamber 6. In the FIGS. 1 and 2 the valve means 43, 44 are closed.

The in the FIGS. 1 and 2 illustrated embodiments of the setting device 1; 121 comprise an electronic control 100 for the representation of the control device 30. A control line 102 controls the electronic control 100 with an electric actuator 104. The electric actuator 104 comprises an electric motor 105 with a shaft 106. At an end of the shaft 106 facing away from the electric motor 105 a gear 108 is indicated, which can be rotatably driven by the electric motor 105.

The gear 108 meshes with a toothing 110, which is designed as a straight toothing. The toothing 110 is designed, for example, on a toothed rack which is provided on the outside of the control sleeve 34. Upon rotation of the gear 108 in the counterclockwise direction, the control sleeve 34 moves in the FIGS. 1 and 2 down, so in setting 15. With a rotation of the gear 108 in a clockwise direction, the control sleeve 34 moves in the FIGS. 1 and 2 upwards, ie opposite to the setting direction 15th

The electric motor 105 of the electric actuator 104 is, for example, a linear motor. Instead of the electric motor 105, the electric actuator 104 may also include another drive, for example a piezoelectric actuator. Differently than shown, the control sleeve 34 for opening and closing the passage openings 31, 32 of the pre-chamber 25 can also be moved differently, for example twisted. The movement of the control sleeve 34 can be done in any manner by applying a voltage.

At the in FIG. 1 Setting device 1 shown, the main combustion chamber 6 is associated with a sensor device 112. The sensor device 112 is connected via a control line 101 in terms of control with the electronic control of the control device 30. The sensor device 112 includes a pressure sensor with which the pressure in the main combustion chamber 6 is detected. During operation of the setting device 1, the sensor device 112 emits a signal which is processed in the electronic control 100.

The electronic controller 100 may have other sensor inputs connected to other sensor devices (not shown). With the further sensor devices, for example, an ambient pressure or a pressure in the pre-chamber 25 can be detected. Alternatively or additionally, an acceleration and / or a temperature at different points in the operation of the setting device 1 can be detected with the further sensor devices.

The electronic control also advantageously includes a user interface. Via this user interface, a user of the setting device 1 can individually set a desired energy for the operation of the setting device 1. With the aid of the electronic control 100, the following operations are controlled, inter alia on the basis of the sensor data and user data during operation of the setting device 1: an electronic control of a metered quantity, a control of the ignition device 26 in the pre-chamber 25 and / or another (in FIG. 1 not shown) ignition device, which may be associated with the main combustion chamber 6. In addition, for example, an unillustrated fan for mixture formation prior to combustion and / or purge of exhaust gases after combustion is controlled by the electronic controller 100.

With the aid of the electric actuator 104, an effective passage cross section in the passage openings 31, 32 of the pre-chamber 25 can be adjusted continuously via the control sleeve 34 in a simple manner. Via the flexible control of the passage cross section, an energy adjustment or energy adjustment by the user is made possible in a particularly advantageous manner. If the user sets the setting device 1 to low energy, then the antechamber venting opens only partially, later or not at all. As a result, during operation of the setting device 1, an air cushion or a cushion of combustion exhaust gases builds up in the pre-chamber 25. By this pad, the driving piston 10 can be braked much gentler, as in a sudden deceleration of the driving piston 10 when it strikes the stops and / or damping elements 28, 29 in the pre-chamber 25. This can reduce device load and extend device life.

With the aid of the electric actuator 104, the closure or release of the passage openings 31, 32 of the pre-chamber 25 can also be controlled in a simple manner as a function of the ambient air temperature and the ambient pressure via the electronic control 100. The two parameters change the Density of the air or the fuel-air mixture before combustion in the pre-chamber 25 and in the main combustion chamber 6. This has an influence on the combustion chamber pressure in the main combustion chamber 6. In order to ensure a simple way a constant energy, the effective flow area of Passage openings 31, 32 are adapted.

At the in FIG. 2 shown setting device 121 is shown that the main combustion chamber 6, a further ignition device 126 can be assigned. About the further ignition device 126, a gas mixture in the main combustion chamber 6 are ignited regardless of whether an ignition in the antechamber 25 has already taken place. As a result, further operating modes of the setting device 121 are made possible.

Unlike the in FIG. 1 Setting device 1 shown is in the in FIG. 2 illustrated setting device 121, a control line 141 is provided, which connects the electronic control 100 of the control device 30 with the ignition device 26 of the pre-chamber 25. As a result, temporal sequence control of the prechamber venting is made possible in a simple manner. In this case, the opening and closing of the passage openings 31, 32 of the pre-chamber 25 is triggered by the control sleeve 34, for example, after a certain period of time after the prechamber ignition.

For example, the electronic controller 100 measures a time interval that begins with the prechamber ignition. After the expiry of the previously set time interval, the passage openings 31, 32 of the antechamber 25 are then released via the electric actuator 104 of the control sleeve 34, that is opened. This provides, inter alia, the advantage that a sensor device (112 in FIG. 1 ) can be omitted.

Claims (10)

An internal combustion setting device (1; 121) for driving fastening elements into a substrate, having at least one main combustion chamber (6) for a fuel, with a driving piston (10) which can be driven via dispersible gases from the main combustion chamber (6) in the setting direction (15) , and with an antechamber (25), which is associated with an ignition device (26) and in which prior to the ignition of a fuel-air mixture in the main combustion chamber (6), a pressure acting on the main combustion chamber (6) pressure is buildable, the prechamber (25) via at least one passage opening (31,32), which is closed by a control device (30) connected to an environment of the pre-chamber (25) or connectable, characterized in that the control device (30) an electronic control (100 ). Internal combustion setting device according to claim 1, characterized in that the electronic control (100) is connected to an electric actuator (104). Internal combustion setting device according to claim 2, characterized in that the electric actuator (104) comprises an electric motor (105). Internal combustion setting device according to claim 2 or 3, characterized in that the electric actuator (104) is mechanically coupled to a control sleeve (34). Internal combustion setting device according to claim 4, characterized in that the control sleeve (34) has a toothing (110) which is coupled via a gear (108) with the electric actuator (104). Internal combustion setting device according to claim 4 or 5, characterized in that the control sleeve (34) is designed and movable relative to the passage opening (31, 32) of the pre-chamber (25) such that the passage opening (31, 32) of the prechamber (25) is movable. is released or closed by the electronic actuator (104) from the control sleeve (34) via the electronic controller (100). Internal combustion setting device according to one of the preceding claims, characterized in that the electronic control (100) is connected to at least one sensor device (112) which is assigned to the main combustion chamber (6). Internal combustion setting device according to one of claims 2 to 6, characterized in that the electronic control (100) is connected to the ignition device (26) which is associated with the prechamber (25). Method for operating a combustion-powered setting device (1; 121) according to one of the preceding claims, characterized in that the control of the passage opening (31,32) of the antechamber (25) is ignition-dependent and / or sensor-dependent. Control device (30), in particular electronic control (100), electrical actuator (104) and / or control sleeve (34), for a setting device (1; 121) according to one of Claims 1 to 8.

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