WO2019233844A1

WO2019233844A1 - Fastener driving tool

Info

Publication number: WO2019233844A1
Application number: PCT/EP2019/063927
Authority: WO
Inventors: Tilo Dittrich; Emanuel Kurth; Chafic Abu Antoun; Peter Roth; Thomas Sperrfechter
Original assignee: Hilti Aktiengesellschaft
Priority date: 2018-06-06
Filing date: 2019-05-29
Publication date: 2019-12-12
Also published as: TW202000393A; EP3578314A1

Abstract

The invention relates to a fastener driving tool, in particular a hand-held fastener driving tool, for driving fastening elements into a substrate, said fastener driving tool comprising a receptacle which is provided to receive a fastening element, a driving element which is provided to convey a fastening element received in the receptacle along a setting axis into the substrate, and a drive which is provided to drive the driving element along the setting axis onto the fastening element, wherein: the drive comprises an electric capacitor, a squirrel-cage rotor located on the driving element, and an excitation coil through which current flows during a rapid discharge of the capacitor and which generates a magnetic field which accelerates the driving element onto the fastening element; and the fastener driving tool has a cooling channel for a flowing cooling medium and a means for generating a flow of cooling medium through the cooling channel.

Description

setting tool

The present invention relates to a setting device for driving fasteners into a substrate.

Such setting tools usually have a receptacle for a fastening element, from which a fastener received therein is conveyed along a setting axis into the ground. A driving element is for this purpose driven by a drive along the setting axis to the fastener.

From US 6,830,173 B2 a setting device with a drive for a driving element is known. The drive has an electrical capacitor and a coil. To drive the driving element, the capacitor is discharged via the coil, whereby a Lorentz force acts on the driving element, so that the driving element is moved towards a nail.

The object of the present invention is to provide a setting device of the aforementioned type, in which a high efficiency and / or a good setting quality is ensured.

The object is achieved in a setting tool for driving fasteners into a substrate, comprising a receptacle, which is intended to receive a fastener, a driving element, which is intended to convey a recorded in the receiving fastener along a setting axis in the ground a drive, which is provided for driving the driving element along the setting axis on the fastening element, wherein the drive comprises an electrical capacitor, arranged on the driving element squirrel cage and an excitation coil, which in a rapid discharge of the capacitor with Current is flowed through and generates a magnetic field which accelerates the driving element to the fastening element, and wherein the setting device has a cooling channel for a flowing cooling medium and a means for generating a cooling medium flow through the cooling channel. The guided cooling medium flow ensures effective cooling of the exciter coil. As a result, more driving operations are possible before the excitation coil and / or other components of the setting device overheat. In addition, a rise in an ohmic resistance of the excitation coil associated with a temperature increase and an associated drop in the efficiency of the drive are reduced or avoided. The setting tool is preferably handheld used. Alternatively, the setting device can be used stationary or semi-stationary. A limitation of the cooling channel is preferably made of an electrically insulating material, such as ceramic.

A capacitor in the sense of the invention is to be understood as meaning an electrical component which stores electrical charge and the energy associated therewith in an electric field. In particular, a capacitor has two electrically conductive electrodes, between which the electric field builds up when the electrodes are electrically charged differently. Under a fastener according to the invention, for example, a nail, a pin, a clip, a clip, a bolt, in particular threaded bolt or the like to understand.

An advantageous embodiment is characterized in that the excitation coil is adjacent to the cooling channel. The excitation coil is preferably arranged in the cooling channel. Also preferably, the cooling channel passes through the exciter coil. Particularly preferably, the exciter coil has at least one turn of a tubular electrical conductor, wherein the cooling channel passes through the electrical conductor.

An advantageous embodiment is characterized in that the setting device has a frame which surrounds the exciter coil. Preferably, the frame consists of a soft magnetic material. Also preferably, the frame adjoins the cooling channel. Particularly preferably, the cooling channel leads through the frame.

An advantageous embodiment is characterized in that the capacitor is adjacent to the cooling channel.

An advantageous embodiment is characterized in that the drive comprises a switching circuit, by means of which the rapid discharge is triggered, wherein the circuit circuit adjacent to the cooling channel. An advantageous embodiment is characterized in that the driving element is adjacent to the cooling channel. The squirrel-cage rotor preferably adjoins the cooling channel. Particularly preferably, the cooling channel leads through the driving element or the squirrel-cage rotor.

An advantageous embodiment is characterized in that the means for

Generation of a cooling medium flow through the cooling channel comprises the driving element, wherein during a movement of the driving element on the fastening element to a back pressure before the driving element and / or a suction pressure behind the driving element generates the cooling medium flow.

An advantageous embodiment is characterized in that the means for

Generation of a cooling medium flow through the cooling passage comprises a rotor conveying a cooling medium and a motor, wherein a rotation axis of the motor and / or the rotor is parallel to the setting axis. Preferably, the engine is an electric motor.

An advantageous embodiment is characterized in that the cooling channel

Has cooling fins.

An advantageous embodiment is characterized in that the setting device comprises a control unit and a means for detecting a temperature of an environment and / or the setting device, preferably the exciter coil, and wherein the control unit is provided, a cooling medium flow through the cooling channel in dependence on the to control the detected temperature. Preferably, a flow rate of the cooling medium flow through the cooling channel is higher, the higher the detected temperature. Also preferably, the control unit is provided to set a running time and / or speed of the means for generating a cooling medium flow through the cooling passage in dependence on the detected temperature. Also preferably, the cooling channel on a controllable valve, wherein the control unit is provided to control the valve in dependence on the detected temperature.

An advantageous embodiment is characterized in that the cooling medium is a gas, preferably ambient air.

An advantageous embodiment is characterized in that the cooling medium is a liquid. Preferably, the liquid is a ferrofluid or a magnetorheological fluid.

In the drawings, the invention is shown in several embodiments. Show it:

1 is a setting tool in a longitudinal section,

2 is a circuit diagram of a setting device,

3 shows an exciter coil in a longitudinal section,

4 shows a setting device in a schematic longitudinal section,

5 shows a setting device in a schematic longitudinal section,

6 shows a setting device in a schematic longitudinal section,

7 shows a setting device in a schematic longitudinal section,

8 shows a setting device in a schematic longitudinal section,

9 shows a setting device in a schematic longitudinal section,

10 is a setting tool in a schematic longitudinal section,

Fig. 1 1 fragmentary a support structure and

Fig. 12 is a setting tool in a schematic longitudinal section.

In Fig. 1, a hand-held setting tool 10 is shown for driving fasteners in a substrate, not shown. The setting tool 10 has a receptacle 20 designed as a bolt guide, in which a fastening element 30 embodied as a nail is received in order to be driven into the underground along a setting axis A (in FIG. 1 to the left). For a supply of fastening elements to the receptacle, the setting device 10 comprises a magazine 40 in which the fastening elements are accommodated individually or in the form of a fastener element strip 50 and are transported gradually into the receptacle 20. The magazine 40 has for this purpose an unspecified spring-loaded feed element. The setting device 10 has a drive-in element 60, which comprises a piston plate 70 and a piston rod 80. The driving-in element 60 is intended to transport the fastening element 30 out of the receptacle 20 along the setting axis A into the ground. Here, the driving element 60 is guided with its piston plate 70 in a guide cylinder 95 along the setting axis A.

The driving element 60 in turn is driven by a drive which comprises a squirrel cage 90 arranged on the piston plate 70, an excitation coil 100, a soft magnetic frame 105, a circuit 200 and a capacitor 300 with an internal resistance of 5 mOhm. The short-circuit rotor 90 consists of a preferably annular, particularly preferably annular element with a low electrical resistance, for example of copper, and is on the of the receptacle 20th opposite side of the piston plate 70 attached to the piston plate 70, for example, soldered, welded, glued, clamped or positively connected. In embodiments not shown, the piston plate itself is designed as a squirrel-cage rotor. The circuit 200 is intended to cause a rapid electrical discharge of the previously charged capacitor 300 and to guide the discharge current flowing through it through the excitation coil 100, which is embedded in the frame 105. The frame preferably has a saturation flux density of at least 1.0 T and / or an effective electrical conductivity of at most 10 ⁶ S / m, so that a magnetic field generated by the exciter coil 100 amplifies from the frame 105 and suppresses eddy currents in the frame 105 become.

In a setting position of the driving-in element 60 (FIG. 1), the driving element 60 with the piston plate 70 dips into an unspecified annular depression of the frame 105 in such a way that the squirrel-cage rotor 90 is arranged at a small distance with respect to the exciter coil 100. As a result, an exciter magnetic field, which is generated by a change in an electrical exciter current flowing through the excitation coil, passes through the squirrel cage rotor 90 and in turn induces an annular secondary electric current in the squirrel cage rotor 90. This developing and thus changing secondary current in turn generates a secondary magnetic field, which is opposite to the excitation magnetic field, whereby the squirrel cage rotor 90 experiences a repelling of the excitation coil 100 Lorentz force, which drives the driving element 60 on the receptacle 20 and the fastener 30 received therein ,

The setting tool 10 further comprises a housing 110, in which the drive is received, a handle 120 with a designed as a trigger actuator 130, designed as a battery electric energy storage 140, a control unit 150, a trigger switch 160, a pressure switch 170, as an means for detecting a temperature of the exciter coil 100 and electrical connection lines 141, 161, 171, 181, 201, 301, which are formed by the temperature sensor 180 and which contain the control unit 150 with the electrical energy store 140, the trigger switch 160, the contact pressure switch 170, the temperature sensor 180, the circuit 200 and the capacitor 300 connect. In embodiments not shown, the setting tool 10 is supplied instead of the electrical energy storage 140 or in addition to the electrical energy storage 140 by means of a power cable with electrical energy. The control unit comprises electronic components, preferably interconnected on a circuit board to one or more control circuits, in particular one or more microprocessors. When the setting device 10 is pressed against a substrate (not shown in FIG. 1 on the left), an unspecified contact element actuates the contact pressure switch 170, which thereby transmits a contact signal to the control unit 150 by means of the connecting line 171. Triggered by this, the control unit 150 initiates a capacitor charging process in which electrical energy is conducted from the electrical energy storage 140 to the control unit 150 via the connection line 141 and from the control unit 150 to the condenser 300 via the connection lines 301 in order to charge the capacitor 300 , For this purpose, the control unit 150 comprises a switching converter (not designated in more detail) which converts the electric current from the electrical energy store 140 into a suitable charging current for the capacitor 300. When the capacitor 300 is charged and the driving member 60 is in its set ready position shown in Fig. 1, the setting tool 10 is in a ready to be placed state. Characterized in that the charging of the capacitor 300 is effected only by the pressing of the setting device 10 to the ground, a setting process is only possible to increase the safety of bystanders when the setting tool 10 is pressed against the ground. In embodiments not shown, the control unit initiates the capacitor charging process already when the setting device is switched on or when the setting device is lifted off the ground or at the end of a preceding driving operation.

If the actuating element 130 is actuated when the setting tool 10 is ready for setting, for example by pulling with the index finger of the hand, which encompasses the handle 120, the actuating element 130 actuates the trigger switch 160, which thereby transmits a triggering signal to the control unit 150 via the connecting line 161. From this, the control unit 150 initiates a capacitor discharging operation in which electrical energy stored in the capacitor 300 is conducted from the capacitor 300 to the exciting coil 100 by means of the switching circuit 200 by discharging the capacitor 300.

The circuit 200 shown schematically in FIG. 1 for this purpose comprises two discharge lines 210, 220 which connect the capacitor 300 to the exciter coil 200 and of which at least one discharge line 210 is interrupted by a normally open discharge switch 230. The circuit 200 forms an electrical resonant circuit with the exciter coil 100 and the capacitor 300. A swinging back and forth of this resonant circuit and / or a negative charging of the capacitor 300 may have a negative effect on an efficiency of the drive, but can be with the help a freewheeling diode 240 prevent. The discharge lines 210, 220 are electrically connected by means of one of the receptacle 20 facing the end face 360 of the capacitor 300 electrical contacts 370, 380 of the capacitor 300, each with an electrode 310, 320 of the capacitor 300, for example by soldering, welding, screwing, jamming or form-fitting. The discharge switch 230 is preferably suitable for switching a discharge current with high current and is designed, for example, as a thyristor. In addition, the discharge lines 210, 220 have a small distance from one another, so that a parasitic magnetic field induced by them is as small as possible. For example, the discharge lines 210, 220 are combined into a bus bar and held together by a suitable means, such as a holder or a clip. In embodiments not shown, the freewheeling diode is electrically connected in parallel to the discharge switch. In further embodiments, not shown, no free-wheeling diode is provided in the circuit.

To initiate the capacitor discharge process, the control unit 150 closes the discharge switch 230 by means of the connection line 201, whereby a discharge current of the capacitor 300 flows through the exciter coil 100 with high current intensity. The rapidly increasing discharge current induces a field magnetic field, which passes through the squirrel-cage rotor 90 and induces in its squirrel-cage rotor 90, in turn, an annular secondary electric current. This secondary current that builds up in turn generates a secondary magnetic field which is opposite to the excitation magnetic field, whereby the squirrel cage rotor 90 experiences a Lorentz force repelling the exciting coil 100, which drives the driving element 60 onto the receptacle 20 and the fastening element 30 received therein. As soon as the piston rod 80 of the driving element 60 strikes an unspecified head of the fastening element 30, the fastening element 30 is driven by the driving element 60 into the ground. Excess kinetic energy of the driving element 60 is absorbed by a braking element 85 made of a resilient and / or damping material, such as rubber, by the driving element 60 moves with the piston plate 70 against the brake member 85 and is braked by this to a standstill. Thereafter, the driving-in element 60 is returned to the setting position by an unspecified return device.

The capacitor 300, in particular its center of gravity, is arranged on the setting axis A behind the driving element 60, whereas the receptacle 20 is arranged in front of the driving element 60. With respect to the setting axis A, the capacitor 300 is therefore axially offset the driving-in element 60 and arranged radially overlapping with the driving-in element 60. As a result, on the one hand, a short length of the discharge lines 210, 220 can be realized, as a result of which the resistances thereof can be reduced and thus an efficiency of the drive can be increased. On the other hand, a small distance of a center of gravity of the setting device 10 to the setting axis A can be realized. As a result, tilting moments during a recoil of the setting device 10 during a driving operation are low. In an embodiment, not shown, the capacitor is arranged around the driving element around.

The electrodes 310, 320 are arranged on opposite sides on a carrier film 330 wound around a winding axis, for example by metallization of the carrier film 330, in particular vapor-deposited, the winding axis coinciding with the setting axis A. In embodiments not shown, the carrier foil with the electrodes is wound around the winding axis so that a passage remains along the winding axis. In particular, in this case, the capacitor is arranged for example around the setting axis. The carrier film 330 has a film thickness of between 2.5 μm and 4.8 μm for a charging voltage of the capacitor 300 of 1500 V, and a film thickness of, for example, 9.6 μm for a charging voltage of the capacitor 300 of 3000 V. In embodiments not shown, the carrier film is in turn composed of two or more individual films stacked on top of each other. The electrodes 310, 320 have a sheet resistance of 50 ohms / n.

A surface of the capacitor 300 has the shape of a cylinder, in particular a circular cylinder whose cylinder axis coincides with the setting axis A. A height of this cylinder in the direction of the winding axis is substantially as large as its diameter measured perpendicular to the winding axis. By a low ratio of height to diameter of the cylinder, a low internal resistance at a relatively high capacitance of the capacitor 300 and not least a compact design of the setting device 10 are achieved. A low internal resistance of the capacitor 300 is also achieved by a large cross-section of the electrodes 310, 320, in particular by a high layer thickness of the electrodes 310, 320, wherein the effects of the layer thickness on a self-healing effect and / or a lifetime of the capacitor 300 are to be considered.

The capacitor 300 is damped by means of a damping element 350 mounted on the other setting tool 10. The damping element 350 damps movements of the capacitor 300 relative to the rest of the setting device 10 along the setting axis A. The damping element 350 is arranged on the end face 360 of the capacitor 300 and completely covers the end face 360. As a result, the individual windings of the carrier film 330 are uniformly loaded by a recoil of the setting device 10. The electrical contacts 370, 380 protrude from the end face 360 and penetrate the damping element 350. The damping element 350 has for this purpose in each case an exemption, through which the electrical contacts 370, 380 protrude. The connecting lines 301 have to compensate for relative movements between the capacitor 300 and the other setting tool 10 each have a discharge and / or expansion loop, not shown. In non-illustrated embodiments, a further damping element is arranged on the capacitor, for example on its end facing away from the receptacle end face. Preferably, the capacitor is then clamped between two damping elements, that is, the damping elements are applied to the capacitor with a bias voltage. In further embodiments, not shown, the connecting lines have a rigidity which decreases continuously with increasing distance from the capacitor.

In Fig. 2 is an electrical circuit diagram 400 of a not shown setting device for driving fasteners is shown in a substrate, not shown. The setting device has a housing, not shown, a handle, not shown, with an actuating element, a receptacle, not shown, a magazine, not shown, a not shown driving-in element and a drive for the driving element on. The drive comprises a not shown, arranged on the driving element squirrel cage, an exciter coil 410, a soft magnetic frame, not shown, a circuit 420, a capacitor 430, an accumulator designed as an electric energy storage 440 and a control unit 450 with a DC as DC, for example The switching converter 451 has a low voltage side ULV which is electrically connected to the electrical energy store 440 and a high voltage side UHV which is electrically connected to the capacitor 430.

The circuit 420 is provided to cause a rapid electrical discharge of the previously charged capacitor 430 and to guide the discharging current flowing through the exciter coil 410. The circuit 420 comprises for this purpose two discharge lines 421, 422 which connect the capacitor 430 to the excitation coil 420 and of which at least one discharge line 421 is interrupted by a normally open discharge switch 423. A freewheeling diode 424 prevents excessive oscillation of a resonant circuit formed by the switching circuit 420 with the exciter coil 410 and the capacitor 430, as well as a negative charge of the capacitor 430. When the setting tool is pressed against the ground, the control unit 450 initiates a capacitor charging process in which electrical energy is conducted from the electrical energy storage 440 to the switching converter 451 of the control unit 450 and from the switching converter 451 to the capacitor 430, around the capacitor 430 charge. The switching converter 451 converts the electric current from the electrical energy store 440 at an electrical voltage of, for example, 22 V into a suitable charging current for the capacitor 430 at an electrical voltage of 1500 V, for example.

Triggered by an actuation of the actuator, not shown, the control unit 450 initiates a capacitor discharge, in which electrical energy stored in the capacitor 430 is conducted by the circuit 420 from the capacitor 430 to the field coil 410 by discharging the capacitor 430. To initiate the capacitor discharge, the control unit 450 closes the discharge switch 423, whereby a discharge current of the high-current capacitor 430 flows through the exciting coil 410. As a result, the squirrel-cage rotor, not shown, experiences a Lorentz force repelling the excitation coil 410, which drives the drive-in element. Thereafter, the driving element is returned by a return device, not shown, in a set ready position.

An amount of energy of the current flowing through the excitation coil 410 during the rapid discharge of the capacitor 430 is controlled in particular steplessly by the control unit 450 by adjusting a charging voltage (UHV) applied to the capacitor 430 during and / or at the end of the capacitor charging process and before the rapid discharge , A stored in the charged capacitor 430 electrical energy and thus the amount of energy flowing through the exciter coil 410 in the rapid discharge of the capacitor 430 current are proportional to the charging voltage and thus controllable by means of the charging voltage. The capacitor is charged during the capacitor charging process until the charging voltage UHV has reached a setpoint. Then the charging current is switched off. If the charging voltage before fast discharge decreases, for example due to parasitic effects, the charging current is switched on again until the charging voltage UHV has reached the setpoint again.

The control unit 450 controls the amount of energy of the current flowing through the excitation coil 410 in the rapid discharge of the capacitor 430 as a function of a plurality of control variables. For this purpose, the setting tool comprises a as the excitation coil 410 arranged temperature sensor 460 formed means for detecting a temperature of the exciting coil 410 and a means for detecting a capacitance of the capacitor, which is formed for example as a calculation program 470 and the capacitance of the capacitor of a course of a current and an electric voltage of the charging current during the capacitor charging process calculated. Furthermore, the setting tool comprises a means configured as an acceleration sensor 480 for detecting a mechanical load variable of the setting device. Furthermore, the setting device comprises a means for detecting a Eintreibtiefe of the fastener in the ground, which includes an example, optical, capacitive or inductive proximity sensor 490, which comprises a reversing position of the drive element, not shown. Furthermore, the setting device comprises a means for detecting a speed of the driving element, which comprises a first proximity sensor 500 formed means for detecting a first time at which the driving member passes during its movement on the fastener to a first position, formed as a second approach sensor 510 means for detecting a second time at which the driving element passes to a second position during its movement on the fastener, and a means configured as a calculation program 520 for detecting a time difference between the first time and the second time. Furthermore, the setting device comprises a user-adjustable control element 530 and a barcode reader 540 designed as means for detecting a characteristic of a fastener element to be driven.

The control variables, in dependence of which the control unit 450 controls the energy amount of the current flowing through the excitation coil 410 during the rapid discharge of the capacitor 430, include the temperature detected by the temperature sensor 460 and / or the capacity of the capacitor calculated by the calculation program 470 and / or the loader size detected by the accelerometer 480 and / or the fastener driving depth detected by the proximity sensor 490 and / or the speed of the driver element calculated by the calculator 520; and / or the user set setting of the operating element 530 and / or the bar code Reader 540 recorded characteristic of the fastener.

Furthermore, the setting device, preferably the control unit 450, comprises means 550 for detecting a temperature of the exciting coil. The means 550, in one embodiment, is a program that processes a signal that the control unit 450 receives from the temperature sensor 460. In another embodiment, the means 550 comprises a means for detecting an ohmic Resistance of the excitation coil, which has a signal generator and a voltmeter. The signal generator generates a measuring current flowing through the exciter coil 410, and the voltmeter measures an electrical voltage drop across the exciter coil 410. A calculation program calculates the ohmic resistance of the exciting coil 410 from the measuring current and the voltage dropped across the exciting coil 410. The means 550 then calculates a difference from the thus-obtained ohmic resistance of the exciting coil 410 and a reference resistor which, in the same manner, after a long time without Setting operation, ie at ambient temperature was detected. The means 550 finally calculates the temperature of the exciting coil 410 from this difference.

In another embodiment, the means 550 comprises a time-detecting means configured as a timer, means for detecting a driving operation as a data receiver which causes a temperature rise of the exciting coil, a data memory in which a standard cooling rate of the exciting coil and the The temperature increase caused by the operation is stored, and a program for calculating the temperature of the exciting coil 410. The driving-in detecting means is formed as an information receiver which receives information from the control unit 450 about a driving operation started by the control unit 450. The temperature of the exciting coil 410 is calculated as follows. After prolonged disuse of the setting device, a device electronics of the setting device is woken up by operating a main switch, a pressure switch, a trigger switch or a motion sensor. The program for calculating the temperature of the exciting coil 410 then reads in a starting temperature detected by the temperature sensor 460 or an ambient temperature sensor as the actual temperature. In addition, the timer is started. As soon as a first driving operation is detected, the temperature rise stored in the data memory is added to the actual temperature and the sum is stored as a new actual temperature. As soon as a further driving operation is detected, a difference is first made between a difference between the actual temperature and the ambient temperature detected by the ambient temperature sensor and the time recorded by the timer, which has elapsed since the last driving operation, using the standard cooling rate stored in the data memory Temperature drop calculated. Subsequently, the temperature drop is subtracted from the actual temperature and the temperature increase stored in the data memory is added and the sum stored as a new actual temperature. After a long time without driving from, for example, two hours, the timer is set to zero and the electronics of the setting device in one Sleep mode offset or disabled. The ambient temperature sensor is preferably arranged on a board of the electronics, for example the control unit 450.

The setting device has a means 560 for cooling the excitation coil 410, which comprises a rotor and is designed for example as a fan or circulation pump for a cooling liquid. The control unit 450 is provided to control the means 560 for cooling the excitation coil 410, for example a running time and / or rotational speed of the rotor, as a function of the detected temperature of the exciter coil 410. In the embodiment described above, an increased cooling rate of the excitation coil 410 is stored in the data memory, and the program for calculating the temperature of the excitation coil 410 during periods in which the means 560 for cooling the excitation coil 410 is not in operation uses the standard cooling rate and in periods where the means 560 is in operation, the increased cooling rate is used.

The control unit 450 is suitable for controlling further operating sequences of the setting device as a function of the detected temperature of the exciting coil 410. For example, the setpoint value for the charging voltage of the capacitor 430 is controlled as a function of the detected temperature of the excitation coil 410, the higher the setpoint temperature of the excitation coil 410, the higher the setpoint value. Further, the control unit 450 enables a drive-in operation only when the detected temperature of the exciting coil 410 is less than a predetermined maximum temperature. On the other hand, when the detected temperature of the exciting coil 410 is greater than the predetermined maximum temperature, the driving operation is inhibited. The means 560 for cooling the exciter coil 410 preferably remains in operation.

In Fig. 3, an excitation coil 600 is shown in a longitudinal section. The excitation coil 600 comprises an electrical conductor, preferably made of copper, with a circular cross-section, for example, which is wound in several turns 610 about a setting axis A ₂ . Overall, the excitation coil has a substantially cylindrical, in particular circular cylindrical outer shape with an outer diameter R _a and a coil length Ls _P in the direction of the setting axis A ₂ . In a radially inner region relative to the setting axis A ₂ , the exciter coil 600 has a free space 620, which is preferably likewise cylindrical, in particular circular-cylindrical, and an inner diameter R which defines the excitation coil.

At one with respect to the setting axis A ₂ axial end face of the exciting coil 600 is formed as a temperature sensor 660 means for detecting a temperature of Exciter coil 600 is arranged and thermally conductively connected to the exciter coil 600, for example by means of a thermal paste. In non-illustrated embodiments, the temperature sensor is arranged on an inner circumference or outer circumference of the exciter coil.

In Fig. 4, a setting tool 700 is shown for driving fasteners, not shown, in a non-illustrated substrate in a schematic longitudinal section. The setting device 700 has a driving-in element 706, which comprises a piston plate 707 and a piston rod 708. The driving-in element 706 is intended to convey a fastening element along an unspecified setting axis into the ground. Here, the driving element 706 is guided with its piston plate 707 in a guide cylinder, not shown, along the setting axis. The driving element 706 is in turn driven by a drive which comprises an annular short-circuit rotor 709 arranged on the piston plate 707, an excitation coil 710, a soft-magnetic frame 705 and a capacitor (not shown). The squirrel cage 709 is attached to the piston plate 707. The exciter coil 710 is embedded in the frame 705 so that the frame 705 surrounds the excitation coil 710 at least circumferentially.

The setting device 700 has a cooling channel 711 for a flowing cooling medium and designed as a fan 712 means for generating a cooling medium flow through the cooling channel 711, which attenuated by means of one or more not shown damping elements in the setting device, in particular on a housing not shown in detail of the setting device 700 is stored. In one embodiment, not shown, the cooling medium is a liquid, preferably a ferrofluid, which supports the soft magnetic effect of the frame 705. The fan 712 has a rotor designed as a fan 713, which is driven by an electric motor, not shown. An axis of rotation of the motor and the fan 713 is oriented parallel to the setting axis. The frame 705 adjoins the cooling channel 71 1, so that cooling medium conveyed by the fan through the cooling channel 711 flows over an outer surface of the frame 705. Thereby, the frame 705 and thus indirectly the exciting coil 710 is cooled. The fan

The setting device further comprises a control unit, not shown, and a not shown, designed as a temperature sensor means for detecting a temperature of an environment or of the setting device, such as the excitation coil. The control unit controls a cooling medium flow through the cooling channel 71 1 as a function of the detected temperature. The control unit is provided to adjust a running time and / or speed of the motor of the fan in dependence on the detected temperature, preferably the higher the detected temperature, the higher. In an embodiment not shown, the cooling channel has a controllable valve, which is controlled by the control unit in dependence on the detected temperature.

In Fig. 5 is a setting device 720 with a driving element 726, which comprises a piston plate 727 and a piston rod 728, a drive, which comprises a squirrel cage 729, an excitation coil 730, a soft magnetic frame 725 and a capacitor, not shown, a cooling channel 731 and a fan 732, which includes a fan 733 shown. The frame 725 adjoins the cooling channel 731, so that the frame

725 and thus indirectly the exciting coil 730 are cooled by an airflow flowing around a surface of the frame 725.

In a setting position of the driving element 726 (FIG. 5), the driving element emerges

726 with the piston plate 727, which is for example cup-shaped, so in an annular recess 735 of the frame 725, that the squirrel cage 729 is arranged at a small distance from the exciter coil 730. As a result, the squirrel cage 729 thereby delivers more heat to the frame 725, so that the squirrel cage 729 is also cooled by the arrangement shown.

In Fig. 6, a setting tool 740 is provided with a driving member 746 including a piston plate 747 and a piston rod 748, a driver including a squirrel cage 749, an exciting coil 750, a soft magnetic frame 745, a capacitor 743, and a fast discharge circuit 744 of the capacitor 743 via the exciter coil 750, a cooling channel 751 and a fan 752, which comprises a fan 753. The condenser 743, the circuit 744 and the frame 745 adjoin the cooling passage 751 and are cooled by an air flow passing through the cooling passage 751.

In Fig. 7 is a setting tool 760 with a driving element 766, which comprises a piston plate 767 and a piston rod 768, a drive, which comprises a squirrel cage 769, an excitation coil 770, a soft magnetic frame 765 and a capacitor, not shown, a cooling channel 771 and a fan 772, which includes a fan 773 shown. The cooling channel 771 passes through the frame 765, so that the frame 765 and thus indirectly the exciting coil 770 are cooled by an air flow flowing through the cooling channel 771.

8, a setting device 780 is provided with a driving element 786, which comprises a piston plate 787 and a piston rod 788, a drive, which has a squirrel cage 789, an exciting coil 790, a soft magnetic frame 785 and a not shown Condenser, a cooling channel 791 and a fan 792, which includes a fan 793 shown. The cooling channel 791 passes through the frame 785 and an air gap between the exciting coil 790 and the squirrel cage 789, so that the exciting coil 790 and the squirrel cage 789 abut the cooling channel 791 and are cooled by an air flow flowing through the cooling channel 791.

In Fig. 9 is a setting tool 800 with a driving element 806, which comprises a piston plate 807 and a piston rod 808, a drive which comprises a squirrel cage 809, an excitation coil 810, a soft magnetic frame 805 and a capacitor, not shown, a cooling channel 811 and a fan 812, which includes a fan 813 shown. The cooling channel 81 1 passes through the frame 805 and through the piston plate 807 of the driving element 806, so that the frame 805 and the driving element 806 and thus indirectly the excitation coil 810 and the squirrel cage 809 are cooled by a flowing through the cooling channel 81 1 air flow.

In Fig. 10, a setting device 820 with a driving element 826, which comprises a piston plate 827 and a piston rod 828, a drive comprising a squirrel cage 829, an excitation coil 830, a soft magnetic frame 825 and a capacitor, not shown, a cooling channel 831 and a fan 832, which includes a fan 833 shown. The frame 825 is supported by a support structure 836 against radially outward forces adjacent to the cooling channel 831, so that the support structure 836 and thus indirectly the frame 825 and the excitation coil 830 are cooled by an air flow flowing around a surface of the support structure 836.

In Fig. 1 1, a section of a support structure 850 is shown. The support structure 850 is composed of a multiplicity of stacked disks 860 made of a metal or alloy and has cooling ribs 870 on an outer side adjoining a cooling channel, which projects into the cooling channel and transfers heat from the support structure 850 to a cooling channel Increase cooling medium. Preferably, the cooling fins 870 are blackened.

12, a setting device 880 is provided with a driving element 886, which comprises a piston plate 887 and a piston rod 888, a drive which comprises a squirrel cage 889, an exciting coil 890, a soft magnetic frame 885 and a capacitor, not shown, and a cooling channel 891 shown. The driving-in element 886 is guided with its piston plate 887 in a guide cylinder 896 along a setting axis not further described. At a front end of the guide cylinder 896, a brake member 897 is disposed. The cooling channel 891 opens with a plurality of openings 898 When driving element 886 is driven by the drive and accelerated downwardly in FIG. 12, a dynamic pressure is created in front of driving element 886 which directs air flow back through cooling channel 891 to an air outlet 899 forces. The driving element 886 thus forms a means for generating a cooling medium flow through the cooling channel 891. The frame 885 adjoins the cooling channel 891, so that the frame 885 and thus indirectly the exciting coil 890 are cooled by the air flow in the cooling channel.

The invention has been described with reference to a number of illustrated in the drawings and not shown embodiments. The individual features of the various embodiments are individually or in any combination applicable to each other, unless they contradict each other. It should be noted that the setting tool according to the invention can also be used for other applications.

Claims

cLAIMS

1. Setting tool for driving fasteners into a substrate, in particular hand-held setting tool, comprising a receptacle which is intended to receive a fastener, a driving element, which is intended to convey a recorded in the recording fastener along a setting axis in the ground a drive, which is provided for driving the driving element along the setting axis on the fastening element, wherein the drive comprises an electric capacitor, a arranged on the driving element squirrel cage and an excitation coil, which is flowed through during a fast discharge of the capacitor with current and a Magnetic field generated, which accelerates the driving element to the fastener, and wherein the setting device has a cooling channel for a flowing cooling medium and a means for generating a cooling medium flow through the cooling channel.

2. Setting device according to claim 1, wherein the exciter coil adjacent to the cooling channel, in particular in the cooling channel is arranged, wherein the cooling channel in particular passes through the exciter coil.

3. Setting device according to claim 2, wherein the exciting coil has at least one turn of a tubular electrical conductor, and wherein the cooling channel passes through the electrical conductor.

4. setting tool according to one of the preceding claims, wherein the setting device has a particular soft magnetic frame, which surrounds the excitation coil.

5. Setting tool according to claim 4, wherein the frame adjacent to the cooling channel, wherein the cooling channel in particular passes through the frame.

6. Setting tool according to one of the preceding claims, wherein the capacitor adjacent to the cooling channel.

7. Setting tool according to one of the preceding claims, wherein the drive comprises a switching circuit, by means of which the rapid discharge is triggered, and wherein the switching circuit adjacent to the cooling channel.

8. Setting tool according to one of the preceding claims, wherein the driving element, in particular the squirrel cage, adjacent to the cooling channel, wherein the cooling channel in particular by the driving element, in particular by the squirrel cage, passes.

9. Setting tool according to one of the preceding claims, wherein the means for

Generation of a cooling medium flow through the cooling channel comprises the driving element, and wherein during a movement of the driving element on the fastening element to a back pressure before the driving element and / or a suction pressure behind the driving element generates the cooling medium flow.

10. Setting device according to one of the preceding claims, wherein the means for

Generating a cooling medium flow through the cooling channel comprises a rotor conveying a cooling medium and a particular electric motor, wherein a rotation axis of the motor and / or the rotor is parallel to the setting axis.

1 1. Setting device according to one of the preceding claims, wherein the setting device comprises a control unit and a means for detecting a temperature of an environment and / or the setting device, in particular the excitation coil, and wherein the control unit is provided, a cooling medium flow through the cooling channel in Controlling dependence on the detected temperature, in particular, a flow rate of the cooling medium flow through the cooling channel is higher, the higher the detected temperature.

12. Setting device according to claim 1 1, wherein the control unit is provided to set a running time and / or speed of the means for generating a cooling medium flow through the cooling channel in dependence on the detected temperature.

13. Setting device according to one of claims 1 1 to 12, wherein the cooling channel has a controllable valve and the control unit is provided to control the valve in dependence on the detected temperature.

14. Setting tool according to one of the preceding claims, wherein the cooling medium is a gas, in particular ambient air.

15. Setting tool according to one of claims 1 to 13, wherein the cooling medium is a liquid, in particular a ferrofluid or a magnetorheological fluid.