Bolt setting device and method for operating same

Technical field

p0001The invention relates to a bolt driving tool for setting fasteners into a substrate, having a working piston which is abruptly moved translationally by igniting a combustible mixture in a combustion chamber to a fastener, such as to put a pin or a nail, wherein the volume of the combustion chamber is adjustable. The invention further relates to a method for operating such a bolt setting device.

State of the art

p0002From German Patent <patcit id="pcit0001" dnum="DE19962695B4"><text>DE 199 62 695 B4</text></patcit> is a portable combustion-powered pin setting tool having a combustion chamber for receiving a combustion mixture, the size of which is lean by an axial displacement of a frontal combustion chamber wall for adjusting the existing in their mixed fuel gas toward or fat-changeable. From German Offenlegungsschrift<patcit id="pcit0002" dnum="DE102005000032A1"><text>DE 10 2005 000 032 A1</text></patcit> is a combustion-operated setting tool with two partial chambers known, between which a separating element, said lead-through openings having an active opening cross section.

Summary of the Invention

p0003Object of the invention is to improve the operation and / or energy efficiency of a bolt driving apparatus according to the preamble of claim 1 further.

p0004The object is in an actuated tool for setting fasteners into a substrate, having a working piston which is abruptly moved translationally by igniting a combustible mixture in a combustion chamber to a fastener, such as to put a pin or a nail, wherein the volume of combustion chamber is adjustable, achieved in that the bolt driving device comprises a control device which is connected to control an adjusting device for adjusting the combustion chamber volume and with a metering valve for metering fuel gas. In the bolt driving tool according to the invention is preferably a portable combustion-powered Stud gun. For setting a fastener is gas, for example from a gas cartridge, mixed in the combustion chamber with oxygen or air to an ignitable mixture. If the ignitable mixture is ignited, then it abruptly expands to drive the working piston. The inventive combination of the adjustment of the metering valve the bolt driving tool can cover a large energy in more efficient energy utilization. The load on the bolt-firing device during operation is significantly reduced, particularly with bolt ratios with minimal energy. This extends the life of the bolt-firing device is prolonged.

p0005A preferred embodiment of the bolt setting device is characterized in that the adjusting device for adjusting the combustion chamber volume a motor, in particular an electric motor comprises. For adjusting the combustion chamber volume, a stepping motor is used particularly preferably. The motor is driven by the control device.

p0006A further preferred embodiment of the bolt setting device is characterized in that the motor is coupled via a transmission with an adjustable chamber wall. The transmission is preferably designed such that it remains self-locking in its current position when a load of the combustion chamber pressure. Moreover, the transmission is preferably designed such that the combustion chamber pressure does not act on the engine. The motor is preferably mounted by means of damping elements in the bolt driving tool.

p0007A further preferred embodiment of the bolt setting device is characterized in that the control device is connected to a control device for power adjustment and / or a display device that displays energy information. With the help of the operating device can be set by a user or users on a simple manner a desired set amount of energy. With the help of the display device can be displayed in a simple manner, the desired set amount of energy. In addition, can be displayed using the display device a minimum and maximum possible amount of energy setting. Thus, the ease of use of the bolt-firing device is significantly increased.

p0008The object indicated above is alternatively or additionally achieved by a method for operating a bolt setting device previously described, wherein with the aid of control means, both the combustion chamber volume and the dosage of the combustion chamber, the fuel gas supplied is adjusted. Thus, the provided in the bolt driving tool for driving fasteners amount of energy can be adjusted very quickly and efficiently. This is possible in particular to collect various fasteners in different substrates without wasting energy. By setting both the combustion chamber volume and the supplied amount of fuel gas, the mixing ratio in the combustion chamber can be adjusted optimally.

p0009A preferred embodiment of the method is characterized in that the current actual combustion chamber volume is detected and compared with a desired target combustion chamber volume. The adjustment of the combustion chamber volume may be stored in the control device.

p0010A further preferred embodiment of the method is characterized in that from deviations between the current actual combustion chamber volume and the desired target combustion chamber volume, a manipulated variable for the adjustment for moving the combustion chamber volume is determined. The target combustion chamber volume is specified by the user or users. The determined manipulated variable is used for controlling the motor, by means of which the combustion chamber volume is adjusted.

p0011A further preferred embodiment of the method is characterized in that the bolt-firing device has a reset function which is triggered by a user interaction and in the setting of the combustion chamber volume and / or dosage forms of the combustion chamber the fuel gas supplied to calibrate / is. The reset function is triggered for example by the insertion of a battery or a gas cartridge in the bolt-firing device.

p0012A further preferred embodiment of the method is characterized in that the adjusting device is moved to adjust the combustion chamber volume when a reset against a stop. At reset, the motor is, for example, proceedings against a stop. On reaching the stop of the motor in the retracted position is left, for example by blocking a further adjustment or by the motor is switched off.

p0013A further preferred embodiment of the method is characterized in that the current actual combustion chamber volume detected with the aid of a sensor device. By comparison with the desired target combustion chamber volume the necessary adjustment of the motor is determined. A reset function for position determination can be omitted here.

p0014A further preferred embodiment of the method is characterized in that the metering valve is normally closed and is opened by the control means for a predetermined time, so that a defined amount of gas flows into the combustion chamber. The gas is removed, for example, a gas cartridge which is replaceably arranged in the bolt driving tool. By varying the opening time of the metering valve, the amount of gas can be adjusted.

p0015A further preferred embodiment of the method is characterized in that a desired set amount of energy, a minimum possible set amount of energy and / or a maximum possible amount of energy set to appear at the Stud gun. The respective set amount of energy is preferably displayed using the display device described above.

p0016Further advantages, features and details of the invention will become apparent from the following description in which various embodiments are described with reference to the drawings in detail.

p0017<figref idrefs="f0001">figure 1</figref> shows a simplified representation of a bolt-firing device of the invention in section with an operating device.

embodiments

p0018In <figref idrefs="f0001">figure 1</figref> is shown in longitudinal section an inventive Stud gun 1 simplistic with a housing. 2 The housing 2 includes a handle 4, in which the bolt-firing device 1 is anpackbar for driving a fastener, which is expelled from a bolt-firing end 5 from the bolt-firing device 1 and can be driven into a substrate.

p0019The energy required for driving the fastener into the substrate is provided inside the bolt-firing device 1, for example in a gas cartridge. 8 The gas cartridge 8 is connected via an adjustable or controllable metering valve 10 with a combustion chamber or a combustion chamber 12th In the combustion chamber 12 is mixed gas from the gas cartridge 8 with air to form a combustible mixture which is ignited to a fastening element, such as to collect a pin or a nail into the ground.

p0020The combustion chamber 12 is surrounded in the interior of the housing 2 by a cylinder fourteenth On one side, in particular an end face of the cylinder 14 of the combustion chamber 12 is closed by an adjustable chamber wall or furnace wall 15th The combustion chamber wall 15 can be adjusted with the aid of an electric motor 16 via a control gear 17, as indicated by a double arrow 18th By adjusting the combustion chamber wall 15 in the direction of the double arrow 18, the size of the combustion chamber 12 in a simple manner can be varied.

p0021State variables in the combustion chamber 12 and / or the position of the adjustable chamber wall 15 can be detected with the aid of a sensor device 20th The sensor device 20 is connected via a sensor line 21 with an electrical or electronic control device 25th The control device 25 is connected via a control line 26 in terms of control with the electric motor sixteenth An accumulator 28, for example a battery, the control device 25 is supplied with electrical energy. Via a further control line 29 the control means 25 is control-connected to the metering valve 10th

p0022The combustion chamber 12 is remote from its the adjustable chamber wall 15 side, in particular front end closed by a piston head 32 of a working piston 34th The working piston 34 is on the one hand with the piston head 32 in a cylinder and on the other hand at its end facing away from the piston head 32 guided in a guide sleeve. Here, the working piston 34 extends through a buffer means 38 therethrough. The movement of the working piston 34 during the driving of a fastener is braked by the fastening element and in the event of excess kinetic energy by the buffer means 38th

p0023The driving a fastener is triggered by a trigger 42 which is actuated by the handle 4, for example, with the index finger. The bolt driving tool 1 of the invention in addition to the trigger 42 includes an operating device 44 with an operating element 45th

p0024The bolt driving tool 1 of the invention comprises in addition to the trigger 42 and the operating device 44, a display device 55 for displaying power information in the operation of the bolt setting device 1. The display device 55 is connected to the electrical or electronic control device 25, and for example comprises a display, by which the energy information alphanumeric and / or graphically, may be, for example, with icons displayed. Alternatively or additionally, the display device 55 having a color display.

p0025The control element 45 of the user or users of the bolt-firing device 1 can specify a target value for the driving energy. The specified setpoint and / or the desired application, for example, "wood" for low amounts of energy, "concrete" for medium amounts of energy and "steel" for high amounts of energy, is displayed by the display device 55th Moreover, the maximum and minimum possible driving energy displayed by the display device 55, which can be delivered to date of the bolt driving tool. 1 Upon reaching overload or underload limits the user is warned by a display element of the display device 55 or by a beep.

p0026In operation of the bolt setting device 1 25 is preferably determined in consideration of environmental parameters, such as ambient temperature and the ambient pressure, for a desired target Eintreibenergiemenge determined with the aid of the control device the corresponding combustion chamber volume and the amount of gas required. To establish the desired combustion chamber volume, the controller outputs 25 signals to the electric motor 16th

p0027The electric motor 16 is preferably designed as a servo-motor and adjusted by the adjusting mechanism 17, the combustion chamber wall 15. The actuating gear 17 is preferably designed so that it at a load through the combustion chamber pressure, which acts on the adjusting gear 17 on the combustion chamber wall 15 by self-locking in its current position remains. In addition, the actuating mechanism 17 is preferably designed so that the combustion chamber pressure does not act on the electric motor sixteenth

p0028The desired combustion chamber volume is stored in the electrical control device 25th a control variable for the electric motor 16 is determined from a difference between a user-defined set point and a stored or position value of the combustion chamber wall 15, with the combustion chamber volume is adjusted via the control gear 17th

p0029The Stud gun according to the invention has a reset function, in which the combustion chamber volume setting will be recalibrated. The reset function is started, for example, by a user interaction. For example, will reset the insertion of the battery 28 or the gas cartridge. 8 When reset, the combustion chamber volume adjustment, for example, the actuating mechanism 17 or the combustion chamber wall 15, proceedings against a stop.

p0030Two different methods can be used for calibration. Firstly, the electric motor can 16 with a sufficiently large number of steps are driven safely to a stop. When the stop is reached, the electric motor 16 is further charged, but blocks the adjustment. This 16 remains the electric motor in its stop position. Alternatively, a current-voltage characteristic curve of the electric motor 16 are detected. In consequence of the change in the current-voltage characteristic when the stop is reached the electric motor 16 is switched off.

p0031According to a further embodiment, the current actual combustion chamber volume detected by the sensor 20th By comparison with the desired target combustion chamber volume, a necessary adjustment of the combustion chamber wall 15 by means of the electric motor 16 can be determined via the control gear 17th When using the sensor 20, the reset function previously described may be omitted.

p0032The dosing valve 10 is preferably operated electrically and is biased in its closed position. In operation of the bolt setting device 1, the metering valve 10 is driven by the control device 25 and is opened for a predetermined time. When metering valve 10 is open, gas can flow from the gas cartridge 8 into the combustion chamber 12th By varying the opening time of the gas quantity can be adjusted.