Handheld Installation Tools

Abstract

A handheld installation tool for installing a nail or a bolt into a substrate, the handheld installation tool comprising: a driver, preferably a gas spring driver or an electric driver, the driver driving an actuator (11), the actuator being used to drive the nail or the bolt into the substrate, characterized by: a decoupling device, the decoupling device at least partially decoupling a first movement process of a first movable part or a piston (111) in the actuator (11) driven by the driver and a second movement process of a second movable part or a piston (112) in the actuator (11) for driving the nail or the bolt into the substrate.

Description

Technical Field

[0001] The present invention relates to a handheld setting tool for driving or installing nails or bolts. Background Art

[0002] Installation tools or nail installation tools that store the energy required for the installation operation in a preloaded gas spring are generally known from WO 2009 / 046076A1 and are sold by Senco under the trade name "Fusion Technology". Tools that work according to the same principle are also provided by HITACHI and should reach a drive energy or installation energy of 120J.

[0003] Such nailers or nail installation tools ("pneumatic installation tools") are well suited for driving nails into or installing nails into wood, but have various disadvantages relative to combustion-driven installation tools which significantly limit the range of applications for such installation tools.

[0004] For example, pneumatic installation tools appear to be less suitable for driving or installing bolts into solid substrates such as steel or concrete, and this is due, on the one hand, to the low driving or installation energy and, on the other hand, to the possible occurrence of recoil. The latter reason can be illustrated with reference to the following limiting case: a nail of length s is to be driven into the substrate, but substrate and nail do not yield at all. In this case, the substrate forms a counter-support for the relaxed gas spring. The relaxation of the gas spring during the installation operation now accelerates the pneumatic gun over the distance s, where the gas spring performs work w=∫(F*ds) with its force F. For the driving energy / installation energy (such as that required for driving / installation into concrete and steel), this can quickly lead to a recoil energy with serious consequences for the user. Recoil is also a problem for electrically driven installation tools.

[0005] Another disadvantage of known pneumatic installation tools is the lower drive energy and the greater weight and volume compared to combustion-driven installation tools with the same drive energy. This disadvantage is mainly due to the lower operating pressure of such devices. For this reason, WO 2009 / 046076A1 explicitly recommends a low operating pressure between 100psig and 120psig, i.e., a pressure corresponding to the common operating pressure of pneumatic actuators: the requirements for piston rings in pneumatic installation tools are very high. The piston rings should keep the pressure loss caused by leakage in the working gas reservoir, i.e., the gas spring, within a small range during the entire service life of the installation tool, but during the installation operation, they must withstand the abnormally high sliding speed for the pneumatic system, and in addition, they must cause as little friction as possible during sliding. If, for example, the pressure is 1.2kpsig instead of 120psig, then in order to achieve sealing, a correspondingly approximately ten times higher pressing force must be used on the seal, and at a piston speed of the order of 30m / s, which is medium for the installation tool, all have already significantly exceeded the PV value of the piston seal commonly found in pneumatic devices. It will therefore be appreciated that WO 2009 / 046076 A1 explicitly teaches that operating pressures much higher than 120 psig cannot be used.

[0006] The company HILTI proposes in DE 10 2007 000 219 B4 to solve the sealing problem by means of a rolling membrane; however, the service life of such a membrane may be problematic due to the high dynamic loads in the installation tool.

[0007] Another problem with known pneumatic installation tools is that it is difficult to adjust the drive energy, which can be achieved more easily with combustion-driven tools, for example. For example, in installation tools driven by burning an ignitable gas-air mixture, the amount of fuel injected can be varied. In pyrotechnic installation tools, the powder cartridge can be loaded with a charge amount adapted to the application.

[0008] A further disadvantage of the last known setting tools comprising a piston drive is that they have a particularly pronounced spring-back and rebound, which can reduce the quality of the setting and can be physically taxing for the user. Summary of the invention

[0009] The object of the present invention is to solve the above-mentioned problems.

[0010] These problems are solved by a handheld installation tool according to one embodiment. In this embodiment, a handheld installation tool for driving a nail or a bolt into a substrate is provided, the handheld installation tool comprising: a driver, the driver driving an actuator, the actuator for driving the nail or the bolt into the substrate; and a decoupling device, the decoupling device at least partially decouples a first movement process of a first movable part or a piston in the actuator driven by the driver from a second movement process of a second movable part or a piston in the actuator for driving the nail or the bolt. The present invention further provides the following preferred embodiments.

[0011] Further advantages and developments of the invention will be apparent from the detailed description which follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A handheld installation tool is shown according to one embodiment.

[0013] Figure 2 An actuator according to one embodiment is shown.

[0014] Figure 3 An actuator according to one embodiment is shown.

[0015] Figures 4a to 4c An embodiment of a tensioning device is shown.

[0016] Figure 5 An actuator according to one embodiment is shown.

[0017] Figure 6 A handheld installation tool is shown according to one embodiment.

[0018] Figure 7 A handheld installation tool is shown according to one embodiment. DETAILED DESCRIPTION

[0019] The invention is described below with reference to further embodiments and examples, and is described based on known pneumatic installation tools and installation tools with electric drive. These examples are used to better understand the invention: but these examples should not be understood as limiting. Here, in the following description, the same reference numerals are used for the same or corresponding elements and repeated descriptions are basically avoided.

[0020] According to one embodiment of a handheld installation tool for driving or installing nails or bolts into a substrate (such as steel or concrete), the handheld installation tool includes: a driver or a piston driver, preferably a gas spring driver or an electric driver, which drives an actuator 11. The driven actuator 11 is used to drive nails or bolts into the substrate. The handheld installation tool also includes a decoupling device, which at least partially decouples a first movement process of a first movable part or piston 111 in the actuator 11 driven by the driver and a second movement process of a second movable part or piston 112 in the actuator 11 for driving or installing nails or bolts. (For better understanding, the figure numerals here only indicate by way of example the installation tool with a gas spring driver) Figure 1 However, this design of the decoupling device can also be used for other drives, in particular for electric drives).

[0021] The decoupling device can advantageously be configured such that the kinetic energy or translational energy of the first movable part or piston 111 (caused by the driver) is transferred to the second movable part or piston 112 and the kinetic energy or translational energy of the second movable part or piston 112 is used to drive the nail or bolt.

[0022] The drive (gas spring drive or electric drive, as will be explained in greater detail below) is thus used to drive the actuator 11 , in other words the travel control element, which in the present case can be designed as a pneumatic actuator.

[0023] The decoupling device here decouples the movement process of the first movable part (e.g. armature) or the first movable piston 111 (e.g. translational movement of the movable part / piston in the cylinder) realized by the drive from the movement process of the second movable part (e.g. mounting element) or the second movable piston 112 (e.g. mounting piston).

[0024] The partial or local decoupling of the movement process is achieved, for example, by ensuring that a translational movement of the first piston does not directly or synchronously or simultaneously lead to a translational movement of the second piston, and vice versa. In other words, the movement process of the first piston preferably leads to a movement of the second piston only after a certain delay. The (direct) rebound is thus not transmitted directly to the first piston and thus to the drive.

[0025] In an advantageous embodiment, the decoupling device can be formed such that the first movable part or the first movable piston 111 is not rigidly connected to the second movable part or the second movable piston 112 or there is no direct contact between them. As is known to those skilled in the art, in this embodiment, a translational movement of the first piston does not directly or synchronously lead to a translational movement of the second piston.

[0026] In another advantageous embodiment, the decoupling device can be formed so that a compressible fluid, such as air, is present between the first movable part or piston 111 and the second movable part or piston 112. Compared with an incompressible fluid, in which the translational movement of the first piston directly or synchronously leads to the translational movement of the second piston due to the incompressible fluid, such as a lubricant, the compressible fluid at least partially decouples the translational movement of the first piston and the second piston. It is understood by a person skilled in the art that, for example, only reaching a certain smaller distance between the first piston and the second piston in conjunction with the compression of the compressible fluid leads to overcoming the moment of inertia of the second movable part or piston, so that the second part or piston can move in order to carry out the installation process.

[0027] Advantageously, the stroke length (i.e., the distance between the first and second dead points) of the first movable part or piston 111 is independent of the stroke length of the second movable part or piston 112. This allows the nail driving energy (nail installation energy) of the driver to be set independently of the installation stroke of the second movable part or piston 112.

[0028] In another advantageous embodiment, the actuator 11 can also have a cylinder, wherein the first piston 111 and the second piston 112 are arranged opposite each other in the cylinder, and wherein at least one piston seal is formed in the cylinder. These piston seals can be one or more piston rings and / or gas dynamic seals. The gas dynamic seal is preferably a labyrinth piston seal type (as will be described in detail below).

[0029] In another advantageous embodiment, the actuator 11 can also be designed so that a reset device (e.g. a helical compression spring) is formed for the second movable part or piston 112. After driving (installing) the nail or bolt, the second movable part or the second movable piston can thus be reset to the initial position and essentially independently of the reset of the first movable part or the first movable piston of the actuator 11.

[0030] In another advantageous embodiment, the drive may have another actuator 10. The other actuator 10 is, for example, part of a gas spring (as further described below) and is coupled to the first movable part or piston 111, so that the driven other actuator 10 realizes the first movement process in the actuator 11. In this embodiment, the installation stroke of the second movable part or piston 112 in the actuator 11 is independent of the travel of the other actuator 10, so that the nail driving energy (nail installation energy) can be set independently of the installation stroke, using which the nail or bolt is driven.

[0031] Figure 1The structure of an installation tool according to another embodiment is schematically shown. Here, the functions of the installation tool are first described with reference to the following components and / or assemblies:

[0032] - Actuator 11 having a first piston 111 and a second piston 112

[0033] - Pneumatic actuator 10 with piston rod 01 and third piston 101

[0034] - Working gas reservoir 20

[0035] -Electrochemical accumulator 90

[0036] -Motor controller 80

[0037] -Motor 70

[0038] -Reducer 60

[0039] - Tensioning device 50

[0040] - Locking device 40

[0041] exist Figure 1 The handheld installation tool shown in is an installation tool with a gas spring drive, which in another advantageous embodiment has at least one working gas reservoir 20 with working gas, and wherein the actuator 10 is a pneumatic actuator. The pneumatic actuator 10 has a third piston 101, which is connected to the piston rod 01. The third piston 101 is in fluid connection with the working gas reservoir 20 and forms a gas spring together with the working gas reservoir 20.

[0042] The pneumatic actuator 10 is movable between a stroke start position range, in which the gas spring is maximally tensioned, and a stroke end position range, in which the gas spring is at least partially relaxed. It is recognized by those skilled in the art that this driven movement of the pneumatic actuator 10 results in a movement of the movable part or piston 111 in the actuator 11 (first movement process), but this movement is at least partially decoupled from the movement of the second movable part or piston 112 (second movement process).

[0043] In other words, the pneumatic actuator 10 (first actuator) forms a prestressed gas spring together with the working gas reservoir 20 and thus forms a gas spring drive. In order to tension the gas spring, the motor 70 is supplied with electric power from the energy storage device 90 (e.g., a battery or a fuel cell) via the motor controller 80. The motor 70 drives the reducer 60. The reducer 60 drives the tensioning device 50. The tensioning device 50 converts the rotary motion of the reducer 60 into a translational motion on the piston rod 01 of the pneumatic actuator 10 and moves the piston of the pneumatic actuator in such a way that the working gas is delivered from the pneumatic actuator 10 to the working gas reservoir 20, i.e., the gas spring is tensioned. The locking device 40 can lock the gas spring in the tensioned state. In order to install a nail or a bolt 140, the locking device 40 is unlocked, for example, by means of an electromagnetic actuator 41. The volume displaced by the piston of the pneumatic actuator 10 when the gas spring is tensioned is called the working volume.

[0044] The following explains Figure 1 Other optional components of the installer tool:

[0045] Reference numeral 30 denotes a valve which can connect the working gas reservoir 20 to the pneumatic actuator 10. The valve can be controlled forcibly by means of a fast electromagnetic actuator 31 including a spring, for example according to DE 10 2009 031 665 A1, so as to introduce a gas pulse from the working gas reservoir 20 into the actuator 10 and close the valve again before the end of the driving process, preferably when the pressure in the working chamber of the actuator 10 exceeds a determined value which is greater than the pressure in the working gas reservoir 20, the valve automatically opens. It will be appreciated by those skilled in the art that in this way the rebound of the installation tool can be reduced during installation in a solid substrate and the user can change the installation energy by selecting the opening time of the valve; however, this leads to a reduction in the electrical efficiency of the installation tool. The valve 30 can also preferably be formed by a piston of the actuator 30, which serves as a shut-off element or has a shut-off element, and the cylinder of the actuator 10 is designed to contain a valve seat, in which case the sealing is achieved by means of a force from a locking device 40, which can have a spring or can be designed to be elastic in order to generate the force (this variant is described later with reference to Figure 2 illustrate).

[0046] Reference numeral 120 denotes a thermocouple, with which the temperature in the working gas reservoir 20 can be measured. Reference numeral 100 denotes a pressure gauge, in particular an electrical or electronic pressure gauge, with which the static pressure in the working gas reservoir 20 can be measured. Reference numeral 21 denotes a second working gas reservoir, which is usually under overpressure relative to the working gas reservoir 20, and the static pressure of which can be measured, for example, by means of a pressure gauge 101. The working gas reservoir 21 serves the purpose of compensating for possible leakage losses of the working gas reservoir 20. This can be done by means of a pressure reducing valve 32. For temperature compensation, the working gas of the working gas reservoir 20 can be heated or cooled, and this can be done, for example, by means of a Peltier element 110 (instead of a Peltier element, a heat pump can also be used, for example), which, by means of cooling or heating bodies 111 and 112, also enables a thermal connection between the working gas in the gas reservoir 20 and the surroundings. Reference numeral 130 furthermore designates a valve via which the gas reservoir 21 , the “refill reservoir”, can be filled with working gas from the outside.

[0047] In a particularly advantageous embodiment, the piston of the actuator 10 with the piston rod 01 does not act on the nail or bolt 140 itself (directly) to drive the nail or bolt. Instead, the actuator 10 acts with its piston rod 01 on a striking mechanism, and the kinetic energy of the actuator 10 (including the components mechanically connected thereto) can be transferred by the first piston (e.g. Figure 1 The piston 111 in the embodiment is transferred to a movable part, such as a second piston (eg Figure 1 The first piston 111 and the movable part or the second piston 112 are not rigidly connected to each other ("decoupling device") and can drive the nail or bolt 140 completely or mostly with the help of the kinetic energy of the movable part.

[0048] For example, by means of the actuator 10 (first actuator) a first piston 111 in another pneumatic actuator 11 ("strike mechanism", second actuator) is driven via the piston rod 01, which can be filled with air (ambient pressure), for example. The pneumatic actuator 11 comprises, in addition to the first piston 111, a second piston 112, such as Figure 1 As shown in . As mentioned above, the first piston 111 can be driven by the actuator 10 and is unidirectional. The second piston 112 of the actuator 11, which is at least partially decoupled from the first piston 111 by the decoupling device, is preferably bidirectional and equipped with a reset device, which is shown here, for example, in the form of a helical compression spring.

[0049] For sealing purposes, the first piston and the second piston of the actuator 11 can be designed in the manner of pistons of a labyrinth piston compressor, so that the necessary temporary sealing can be achieved gas-dynamically.

[0050] In order to drive the nail or bolt 140, by releasing the locking device 40, the piston rod 01 and thus also the piston of the actuator 10, as well as the first piston 111 of the actuator 11 connected to the piston rod 01, are accelerated by means of the preloaded gas spring. As a result, the pressure between the first piston and the second piston of the actuator 11 increases almost exponentially: the momentum and kinetic energy are transferred from the part of the installation tool directly driven by the gas spring (the piston 101 of the actuator 10, the piston rod 01, and the first piston 111 of the actuator 11) to the second piston 112 of the actuator 11 and thus also to its piston rod and the components connected to the piston rod (such as the return spring) through the gas buffer formed between the first piston and the second piston of the actuator 11. For this purpose, the active masses are coordinated with each other by the professional, taking into account the possible reduction of mass (weight). The installation of the nail or bolt 140 is finally achieved by the piston rod of the second piston 112 of the actuator 11. If the second piston 112 of the actuator 11 is designed to act in both directions, that is, if the side of the cylinder of the actuator 11 facing the nail is closed sufficiently tightly, a second fluid or gas cushion (such as a gas cushion) can be established in the cylinder of the actuator 11 on the side of the second piston 112 facing the nail during the installation process, which can reset the second piston. Figure 1 This fluid or gas cushion prevents the second piston 112 of the actuator 11 from hitting hard on the nail or bolt 140.

[0051] There should be a gap between the piston rod of the second piston 112 of the actuator 11 (used to drive the nail or bolt 140) and the nail 140 itself to allow sufficient momentum transfer (preferably at least 50%) from the first piston to the second piston of the actuator 11 before starting to accelerate and eventually start driving the nail: the driving energy preferably comes mostly from the kinetic energy of the second piston of the actuator 11 (including its piston rod, etc.).

[0052] In order to achieve a short overall length of the actuator 11 and / or only a small gap between the piston rod and the nail, the energy transfer from the first piston to the second piston of the actuator 11 should take place as suddenly as possible, which can be achieved in at least two possible ways: (i) Firstly, one or more vent openings (vent openings) can be provided in the cylinder, so that the first piston can be set in motion and gas or air can be conveyed through this (these) vent openings, for example into the setting tool housing, so that the movement of the first piston does not initially lead to a significant pressure increase in the cavity between the first piston and the second piston. The vent openings are only substantially closed by the first piston 111 in the actuator 11, which is accelerated by the piston drive or its actuator 10, sweeping over the vent openings, so that a significantly greater, in particular steep-sided, pressure increase occurs in the space between the two pistons of the actuator 11 than would be the case if no vent openings were present. (ii) Secondly, the second piston 112 of the actuator 11 can be blocked by means of a mechanism, so that the second piston can only be set in motion when a certain burst force is exceeded. Such a mechanism can be operated in a form-fitting or force-fitting manner and is known, for example, from so-called force limiters and from bolt arrangements of guns. These two variants can be combined with one another.

[0053] The actuator 11 makes the installation stroke and the travel of the preloaded gas spring (formed by the actuator 10 and the working gas reservoir 30) essentially independent of each other. This makes it easier to provide a variable drive energy: only the travel (with which the gas spring is tensioned) and thus the working volume need to be adjusted. This does not change the installation stroke determined by the actuator 11.

[0054] Other aspects of the embodiments of the structural features of the components of the installation tool according to the present invention are described below:

[0055] Figure 2 Show Figure 1 Another possible embodiment of a pneumatic actuator 10 (first actuator) for a gas spring.

[0056] As described in detail below, the third piston 10a includes a plurality of piston rings 15a, wherein a cavity 16a is arranged between the piston rings 15a in the axial direction, that is, in the direction of movement of the third piston 10a, or the piston is constructed to have such a cavity, which is preferably partially, but not completely, filled with an incompressible fluid.

[0057] exist Figure 2 In the embodiment, the piston 10a together with the piston rod 11a is arranged in a cylinder 12a. The cylinder 12a is designed to contain a valve seat 13a towards the high-pressure side p1, that is, towards the working gas reservoir. The piston 10a is designed as an associated shut-off element. Figure 1 The tensioning device 40 can preferably exert sufficient pressing force on the piston 10a by means of a spring in the locked state, so that the working gas reservoir is additionally sealed in the locked, tensioned (ready to fire) state by means of a valve (formed by the piston and cylinder as described). The function of the valve here corresponds to Figure 1 Valve 30. Figure 2 The piston rod 11a and Figure 1 The piston rod is the same as 01.

[0058] exist Figure 2 In the embodiment, the piston 10a has, for example, two piston guide rings 14a. Figure 2 The preferred piston is characterized in that the piston 10a also has a plurality of piston rings 15a, the contact forces of which can be applied, for example, by O-rings, but can also be applied in all other known types and ways. Figure 2 Four piston rings 15a are shown in FIG, but more or fewer piston rings 15a may also be provided. Between each piston ring 15a, the piston 10a is also configured to have a plurality of chambers or cavities. Preferably, these cavities are partially, but not completely, filled with a liquid lubricant.

[0059] The multiple cavities in cascade form (that is, the cavities are connected in series, so that the effect of each cavity is derived from the previous cavity and acts on the next cavity) not only ensures reliable lubrication but also achieves a uniform distribution of the pressure to be sealed to the different seals. The pressing force of each seal can be reduced accordingly and the p*v stress of each individual seal can be reduced accordingly. Figure 2 In the starting stroke position shown in FIG, the valve formed by the cylinder 12a and the piston 10a is closed. In this position, therefore, the working gas must first overcome the valve and then the entire cascade of lubricated piston rings and cavities in order to escape from the working gas reservoir at pressure p1 to the low-pressure side p0. Only during the subsequent adjustment process, during which the piston 10a is completely returned to its starting stroke position, is a leakage of the cascaded, "cushioned" and lubricated piston ring (sliding ring seal) detected.

[0060] It is recommended that the piston 10a and the cylinder 12a be made of sufficiently tough, hard, particularly wear-resistant and highly polishable steel. Very suitable materials include steel (e.g. 1.4108), i.e. cold-working steel and in particular pressure-nitrided steel with a very fine martensitic structure, further characterized by the absence of large-grained carbides or carbonitrides, where "large-grained" also means that linearly precipitated carbides have a maximum extension size in one direction of more than 20 μm and preferably more than 10 μm.

[0061] Preferably, when using steel 1.4108 (material number) for the piston 10a and the cylinder 12a, a slightly higher Rockwell hardness is set for the cylinder 12a than for the piston 10a by corresponding tempering (eg 56-58 HRC for the piston and 58-60 HRC for the cylinder or its working surface).

[0062] In addition to the cold-formed steels mentioned, new materials are particularly suitable for pistons and / or cylinders which can be processed to a near-net contour using so-called additive manufacturing methods (e.g. laser sintering). Examples here include particularly hard, sufficiently tough powder metallurgical steels (e.g. Vibenite 290) and metallic glasses based on elements of the fourth subgroup.

[0063] The working surfaces of the piston 10a and the cylinder 12a can very preferably be coated with a hard material layer or a friction layer. For coating the cylinder 12a or its working surface, CVD-deposited, mainly tetracoordinated carbon (ta-C) is particularly suitable. As a coating for the piston 10a, ta-C is also suitable, but also aC / WC, TiN, TiMoN (as a solid phase solution or MoN / TiN "superlattice"), TiN-MoS2 and nitrides, carbides and carbonitrides of Cr, Ti, Zr, Hf are also suitable, and amorphous aluminum oxide (and / or aluminum oxynitride) present as nanocrystalline or microcrystalline corundum is also suitable. Particularly suitable for the piston rings are professionally selected, especially high temperature and wear resistant plastics selected from the following group: polyetheretherketone (PEEK) and / or polyimide (PI) and / or ultrahigh molecular weight polyethylene (UHMWPE) and / or liquid crystal, preferably filled with solid lubricants such as PTFE and / or graphite and / or hexagonal boron nitride (hBN) and / or MoS2 and optionally (especially ceramic) reinforced with glass fibers, carbon fibers, fumed silica; further preferably, the piston ring material can also be selected in such a way that it has a low sliding film coefficient with the friction counterpart, i.e. the working surface of the cylinder 12a, does not adhere significantly to the friction counterpart as far as possible, has a high thermal conductivity and a low thermal expansion coefficient. Carbon-based materials, such as graphite impregnated with antimony, are considered for the guide rings.

[0064] according to Figure 2 Actuator 10( Figure 1A professional implementation of the working gas reservoir 20 (in the embodiment of the present invention) allows working at very high pressures (e.g. at least 10 bar, more preferably at least 20 bar, more preferably at least 40 bar, more preferably at least 60 bar, more preferably at least 80 bar, more preferably at least 100 bar, more preferably at least 120 bar) and piston speeds (e.g. at least 30 m / s, preferably more than 5 m / s) without having to operate the working gas reservoir 20 ( Figure 1 ) to compromise the sealing performance.

[0065] Figure 3 Show Figure 1 Another possible implementation of the pneumatic actuator 10 (first actuator).

[0066] As described in detail below, the pneumatic actuator 10 includes, in addition to the third piston 10b, a fourth piston 11b, between which a reservoir 13b is formed, which is filled with an incompressible fluid which preferably has the properties described below and is coordinated with the working gas as described below.

[0067] This basis Figure 3 The embodiment of the invention thus shows a completely different and new possibility of realizing a sealed gas spring. Figure 1 ) of the piston rod 01 or even the same piston 101 in Figure 3 In the figure, it is indicated by the reference numeral 11b. In addition, there is a second piston 10b, which has, for example, two guide rings 14b and, for example, a piston ring 15b. The two pistons 10b and 11b are not rigidly connected to each other. 12b represents the cylinder of the pneumatic actuator (first actuator 10). In addition, there is a reservoir 13b arranged in the cylinder 12b between the two pistons, which is filled with a fluid (an incompressible fluid). This is preferably a liquid lubricant, in which polymers or oligomers and / or dispersed solid lubricants such as MoS2 and / or hBN and / or graphite are dissolved and / or solid lubricants are dispersed, if necessary with the addition of stabilizers, so that the fluid has obvious shear-thinning properties and, if necessary, also exhibits thixotropic properties (the thixotropy of the fluid in the reservoir 13b can mechanically unload the locking device 40 during unlocking). Reference numeral 16b indicates a sealing ring, for example a so-called clad carbon ring. For the material selection involving the piston and cylinder and also possible coatings, as described above for Figure 2 The same contents of the description apply. A person skilled in the art will recognize that such a seal is not a decoupling device (as described above) because due to the incompressible fluid the pistons 10b and 11b are not decoupled but move synchronously with each other. The movement of the piston 10b here directly leads to the movement of the piston 11b and vice versa.

[0068] Figures 4a to 4c Shown in Figure 1 A possible embodiment of the tensioning device schematically indicated by reference numeral 50 in the figure, wherein the tensioning device causes the piston 10 ( Figure 1 ) sports. Figure 4a In the middle, 10c means Figure 1 The piston rod 01, 11c represents the lifting element of the piston rod, 20c and 30c represent two mutually meshing gears, and the gears have a flywheel device located thereon, and the flywheel device is composed of components 21-23c and 31-33c respectively ( Figure 4b and Figure 4c The reference numerals in the drawings are similar with suffixes d and e).

[0069] The gear can be Figure 1 The electric motor denoted by reference numeral 70 is set in rotation via a reduction gear 60, where it is sufficient to drive one of the two mutually meshing gears. A planetary gear transmission preferably designed as a multi-stage transmission (all stages are two-shaft operation) is particularly suitable as a transmission 60. By engaging a flywheel device in the piston rod, the rotary motion of the transmission 60 and thus also the gears can be converted into a linear motion. Three figures are used to symbolically illustrate different operating states of the tensioning device.

[0070] Figure 4a The tensioning process is shown, in which the piston rod overcomes the pneumatic actuator 10 ( Figure 1 ) in the working gas (over) pressure p1. Here, the travel of the piston and thus also the energy stored in the gas spring can be selected: the piston rod is locked by means of the locking unit 40 ( Figure 1 ) is locked against the force of the gas spring. (via motor 70 via Figure 1 The transmission 60) drives the gear 20c with the ratchet flywheel in a first rotation direction, and the gear 30c meshing with 20c is driven thereby, but can also be driven by a motor like 20c. The force is transmitted to the piston rod 10c via the ratchet flywheel 21c / 22c / 23c or 31c / 32c / 33c. In the double-sided force transmission shown, the lateral loads on the relevant bearings and / or seals on the piston and / or piston rod 10c can be avoided or reduced. However, in principle, a single-sided drive, for example, only via the gear 20c is also sufficient.

[0071] Figure 4b The reverse direction of rotation is shown, in which the piston rod is not driven because the drive element of the flywheel is not engaged with the lifting element of the piston rod. Figure 4b The middle position moves to Figure 4cShown in the position, in this position avoid any contact between the piston rod 10e and the flywheel 21-23e / 31-33e on the gear 20e / 30e. During the installation process, that is to say during the sudden axial movement of the piston rod 10e in the direction of the arrow, then avoid the contact of the push and lift element. Figure 4c The gear position can be determined, for example, by a drive ( Figure 1 The self-locking of the motor 70 with a high transmission ratio 60 ensures that no additional locking is required.

[0072] The ratchet flywheel comprises a drive element 21c which is rotatably mounted and has a stop or any other limiting structure, so that when the drive element 2c and the lifting element 11c of the piston rod are engaged, the piston rod 10c is driven in one rotational direction of 20c. However, in the opposite rotational direction of 20c, the drive element 21c can be moved over the lifting element 11c substantially without resistance, in that the drive element moves about its rotation axis so that it can pass by the lifting element. Figure 4b This shows a state in which the drive element 21d moves away from the lifting element 11d.

[0073] The drive element here is preferably constructed as a ratchet of a ratchet flywheel and can be configured to match a corresponding lifting element (e.g. "tooth") on the piston rod, where linear loads between the drive element and the lifting element are avoided as much as possible and the goal is to achieve surface loads (Stribeck pressure, not Hertzian stress).

[0074] In addition to the drive element and its rotatable arrangement with a stop / limiting device, the flywheel also includes a device for moving the drive element from a retractable position (such as Figure 4b 21d and 11d shown in the relative positions) returns to the drive position (as shown in the Figure 4a The mechanism can be, for example, a spring 22c with a counter bearing 23c. One possible implementation is, for example, a torsion spring (helical torsion spring) coaxial with the rotatable arrangement of the drive element, one spring leg being fixedly connected to the drive element and the second leg being fixedly connected to the gear 20c.

[0075] Now through Figure 1The actuator 11 (second actuator) can adjust the drive energy independently of the installation stroke simply by the travel distance and thus by the working volume used to preload the gas spring. Preferably, the piston rod 01 has a reinforcement structure perpendicular to the lifting element, with which the drive element of the tensioning device 50 engages or on which the drive element is engaged. The reinforcement structure is used to increase the bending force that the piston rod 01 can reliably withstand; the piston rod can also be configured to have a locking element, to which the locking device 40 can be engaged. As an additional mechanism for reinforcement, the piston rod can be configured to have a reinforcement ring.

[0076] Figure 5 Another alternative embodiment of the actuator is shown, in particular Figure 1 The basis of Figure 2 A simple and realizable variant of the actuator 10 (first actuator).

[0077] As described in detail below, the pneumatic actuator 10 here includes a cylinder 12f, which is configured to include a valve seat 13f, and the third piston 10f is configured to act as a shut-off element of the valve seat or include a corresponding shut-off element, so that the third piston 10f and the cylinder 12f together form a valve, and the valve can be closed by using sufficient external force to press the third piston 10f and thereby the shut-off element against the valve seat 13f formed by the cylinder 12f or attached to the cylinder.

[0078] Therefore, in Figure 5 10f and the valve formed by the piston 12f, 14f and 17f are guide rings (for example, made of antimony-impregnated graphite), 15f is a piston ring, the piston ring is for example made by the above reference Figure 2 Reference numeral 16f denotes a ring having a U-shaped or also a double U-shaped profile, which forms the sealing material already discussed. Figure 2 The preferred part of the cavity described is filled with lubricant; these rings are correctly inserted onto the piston via the piston rod 11f. The pressure required for sealing can now be applied by means of the force of the preloaded (disc-shaped) spring assembly 18f and the nut 19f. Preferably, a thread locking lacquer is provided in the thread of the nut 19f, which thread locking lacquer can be filled with metal powder.

[0079] Other aspects of the embodiments of the present invention are described below, which are particularly convenient for those skilled in the art to implement the present invention:

[0080] For the motor 70, a so-called brushless DC motor is particularly suitable, and such a brushless DC motor preferably has an axial magnetic flux distribution. Such a magnetic flux distribution achieves a very high power density while having a high electrical efficiency, and its polarity achieves sufficient stopping torque through the permanent magnets so that after deceleration through the transmission 60, the motor is decelerated according to the rotation of the gearbox 60. Figures 4a to 4c The tensioning device is reliably maintained at Figure 4c ; thus, the person skilled in the art does not have to use the self-locking generated by the internal friction of the transmission 40 and does not have to provide an additional locking device for the tensioning device (relative to the locking device 40). The motor 70 can advantageously be designed asymmetrically to have a higher electrical efficiency at a certain rated shaft power in the direction of rotation of the tensioning gas spring (i.e., for example, the flywheel device meshes with the piston rod 01). The motor 70 and also the motor controller 80 can be stationary or passively cooled with air; for applications with particularly high requirements for installation frequency and / or installation energy, evaporative cooling can also be used to cool these two components.

[0081] The working gas reservoir 20 preferably encloses a volume Va for which Figure 1 The maximum working volume Vh of the actuator 10 satisfies the following: preferably Va>=Vh, more preferably Va>=2*Vh, more preferably Va>=3*Vh and more preferably Va>=4*Vh. In the fully tensioned state, the operating pressure in the working gas reservoir 20 is preferably at least 10 bar, more preferably at least 20 bar, more preferably at least 40 bar, more preferably at least 60 bar, more preferably at least 80 bar, more preferably at least 100 bar and more preferably at least 120 bar. Maraging steels are particularly suitable as materials for the working gas reservoir. Of these maraging steels, corrosion-resistant types (colloquially referred to as "stainless steels") are particularly preferably used, or other approaches can also be used to achieve corresponding corrosion protection. Alternatively, fiber-reinforced plastics can be used instead of steel, which plastics can also be designed to avoid diffusion losses by means of one or more layers forming a diffusion barrier structure. In principle, hardenable aluminum-plastic alloys, such as aluminum 7068, and titanium alloys, such as Ti-6Al-V4, are also very suitable as materials for the working gas reservoir.

[0082] As working gas, nitrogen that is as dry as possible is suitable ("as dry as possible" in the present case means that the formation of dew can be reliably avoided in the entire working area). The use of a light gas (i.e., in practice helium, since hydrogen is rarely considered due to its reactivity (flammability and, if necessary, the risk of hydrogen embrittlement)) instead of nitrogen has the advantage that, due to its high sound velocity, gas dynamics have only a less significant effect even at relatively high piston speeds: that is, with heavier gases and higher piston speeds, during the installation process, due to the piston movement, there is first a non-zero reduction in the working gas pressure at the bottom of the piston (of the working piston of the actuator 10), followed by a subsequent pressure increase ("overshoot") during the subsequent sudden deceleration of the piston; this process is associated with irreversibility, i.e., a reduction in efficiency, and in addition, an unfavorable distribution of the forces over the travel of the gas spring.

[0083] On the other hand, polyatomic gases and in particular gases with more than two atoms (such as CF4) offer the advantage of having a smaller isentropic index, which, under the same initial conditions and the same compression ratio, leads to a smaller temperature increase of the working gas during compression (i.e. when the gas spring is tensioned) and thus to smaller heat losses and thus to smaller irreversibility than is the case for monatomic gases. Gas mixtures can also be considered. For example, CO2 can be added to nitrogen in order to increase the isentropic index of the gas mixture. The use of CO2 as the working gas (working medium) also offers the advantage that it can be replenished with a very high density in the refilling reservoir ( Figure 1 In the gas spring (reference numeral 21 in the figure), a working medium for compensating leakage losses is stored. In order to achieve high operating pressures according to the invention, in the described design of the gas spring, it is preferably taken into account that the corresponding working gas is no longer regarded as an ideal gas: the cohesive pressure and the covolume do not disappear. In each case, it is preferred that the working gas (whether pure gas or mixture) is coordinated with the piston rings and the lubricant: the working gas or these working gases should dissolve as little as possible in the lubricant and have the smallest possible diffusion rate in the lubricant in order to achieve the smallest possible leakage rate. In the present case, the leakage rate can be regarded as being as small as possible when the installation tool can achieve at least 10,000 installations under all common environmental conditions and can be stored for at least 5 years without the need for refilling of the working gas.

[0084] The cylinder and the working gas reservoir can be understood as a piston drive and a basic problem occurs with installation tools having an installation piston: a sudden movement of the piston mass during the installation process and in particular during the driving of nails or bolts can lead to a noticeable springing of the installation tool, which affects the quality of the installation.

[0085] Regarding the fastening quality, this problem is known and has been solved, see for example WO 2019 / 121016 A1.

[0086] Furthermore, the strong springing and rebounding result in a high physical strain on the staff. The reason for the springing is, on the one hand, that the extended movement path of the piston's center of gravity usually does not intersect the center of gravity of the setting tool. On the other hand, the center of rotation D1 (constraint) is formed by holding the setting tool at the handle, which is also located next to the movement path of the piston's center of gravity. As a result, the setting tool is known to spring and rebound violently during the setting process and also during the driving process. The present invention is also unable to avoid this problem.

[0087] However, the problem can be at least substantially eliminated as shown below by way of example, which is also not to be understood as restrictive:

[0088] Figure 6 Another preferred embodiment of the handheld nail setting tool according to the present invention is shown.

[0089] Install the piston 610 (e.g. Figure 1 In the case of using a decoupling device, the second movable part or piston 112 has at most a quarter of the mass of the drive 600. The drive 600 is particularly advantageously arranged in the setting tool so that it can be moved axially, for example on a guide structure 690.

[0090] Therefore, the piston drive 600 (eg gas spring drive, electric drive, etc.) is designed here so that it has a significantly higher mass than the piston 610 itself, preferably four times the mass and particularly preferably more than ten times the mass.

[0091] Piston driver 600 (in the present case, for example (see Figure 1) comprising a motor 70, a reducer 60, a tensioning device 50, a locking device 40, a piston of an actuator 10, possibly with a valve, and a working gas reservoir 20) is movably arranged in or on the installation tool along the movement axis of the piston 610, for example by means of one or more rails or other guide structures 690, where the extended movement path of the center of gravity S1 of the piston preferably passes through the center of gravity S2 of the piston driver 600, as long as it is achievable structurally and within the scope of manufacturing accuracy, and the piston driver 600 has at least one stroke start position A, and a stroke end position range B. As long as no installation operation is carried out, an additional locking device 620 fixes the piston driver in the stroke start position A relative to the rest of the installation tool and in particular relative to the handle 630 of the installation tool. During the installation operation, the locking device 620 is unlocked / released actively (for example by means of an actuator) or passively (for example by rebounding itself), whereby during the installation operation, the piston driver 600 is first allowed to return through a determined travel distance s'. The travel distance s' is particularly preferably designed so that the driving of the nail or bolt ends before the travel distance is "exhausted", that is, before the piston driver 600 moves back over the travel distance s'. Then, the shock absorber 640 (for example, a hydraulic buffer with an elastomeric stop 650 and a return spring 660) starts to work and starts to brake the piston driver 600 over the buffer distance s". Figure 1The shock absorber 640 preferably works under irregular limit conditions. The described arrangement requires a reset device so that the piston driver 600 is transported back to the stroke starting position after the installation process and locked here by means of a locking device 620. In the simplest case, this can be achieved by a spring, in particular a helical compression spring or a wave ring spring, which is similar to the firing spring of an automatic loading shooting weapon. In an installation tool with a propelling charge, the return energy can also be partially used for "ammunition delivery" (casing, nails) in a known manner. During the return stroke of the piston driver 600 is buffered, the user is subjected to a torque on the handle 630 of the installation tool, which mainly causes the wrist joint of the user to be subjected to a mechanical load. This torque can also be reduced numerically in favor of the staff, in that the handle 630 of the installation tool is, for example, rotatably connected to a housing 680 of the installation tool by a hinge 670, in which the piston driver 600 is movably arranged. This rotational movement can also be damped and reset, for example by means of one or more hydraulic shock absorbers 641 with one or more return springs, which can also be achieved by means of polymer buffers; a locking device 621 similar to the locking device 620 can also be used and may be advantageous if necessary. If present, this locking device is preferably unlocked directly before the piston drive 600 is still damped in the return stroke and in particular after the installation process is completed (!). After the return to the stroke start position, for example by the spring of the second buffer 641, the locking device 621 is locked.

[0092] In contrast to the prior art, the method described not only improves the nail driving quality but also, in particular with regard to the force peaks occurring during the installation operation, simultaneously significantly reduces the biomechanical stress on the personnel, which can lead to fatigue and injuries.

[0093] Of course, the installation tool that is buffered by the method described above is heavier than the installation tool without buffering due to the parts required to perform the method. However, the additional weight is allowed to vary within a range of about 3% to 10% of the common installation tool. The installation tool involved in the embodiment of the present application is characterized by a high installation energy density and can still be constructed lighter than, for example, a conventional installation tool. The piston drive of the installation tool driven by combustion and especially gunpowder, and the piston drive based on an electric drive (such as a Thomson coil) can have a particularly high installation energy density with respect to gravity and / or a particularly high force increase rate on the piston, so that the buffering method described above for such an installation tool may be particularly beneficial to protect the staff from fatigue and injury. The situation described later becomes more important due to the increasingly stringent labor protection regulations in the future.

[0094] Due to friction and necessarily due to the force of, for example, the return spring 660, a certain small rebound still occurs due to the gripping of the handle 630 and the resulting rotation center D1 at the hinge 670; in order to further reduce this rebound, the structure can make it possible that the extension path of the center of gravity S1 of the piston 610 does not pass exactly through the center of gravity of the piston driver 100, but is more parallel to the direction of movement of the piston and slightly offset in the direction of rotation center D1.

[0095] For example, with the help of Figure 1 The decoupling device formed by the actuator 11 in the embodiment of the present invention can also realize an installation tool different from an installation tool with a gas spring. For example, particularly powerful electric drives with active mutually repelling coils are known, for example from WO 2012 / 079572 A2 and WO 2014 / 056487 A2. For example, an installation tool can be realized in which, instead of a gas spring or a gas spring drive, a gas spring drive according to WO 2012 / 079572 A2 is used. Figure 2 An electric drive, whose movable armature together with its excitation coil A acts as a movable "piston". However, the electric drive is not unproblematically suitable for use as a drive for an installation tool for the following reasons:

[0096] (A) For a stroke designed to correspond to the installation stroke of the nail installation tool, a mass that is too high for the driver is obtained;

[0097] (B) The necessary piston speeds in the setting tool lead to high dynamic loads on the flexible strands, via which the drive is supplied with electrical power;

[0098] (C) When using powder composite materials ("SMC") for an armature ("piston") which allows a particularly high electrical efficiency, there is a risk of the armature breaking in the event of an uncontrolled deceleration of the armature (for example during installation in a solid substrate or in the event of incorrect installation).

[0099] In this context, another embodiment of the handheld installation tool comprises an electromagnetic drive, which preferably has a Thomson coil actuator, for example according to WO 2018 / 104406A1 (see the document Figure 1), that is, an electric drive comprising a first excitation coil, a soft magnetic frame and a squirrel-cage rotor or a squirrel-cage winding which is movably mounted along an axis, the soft magnetic frame having a saturation magnetic flux density of at least 1.0 T and / or an effective specific conductivity of at most 10^6 S / m. In this electromagnetic drive, the frame is configured as a "flux concentrator", the first excitation coil is directly or indirectly mounted on the frame and is formed, for example, from a fiber-reinforced flat wire. In this embodiment, the hand-held setting tool also has the decoupling device described above, the movably mounted squirrel-cage rotor or the movably mounted squirrel-cage winding being formed in a (e.g. slidably mounted) movable element (piston, armature), which realizes the movement process of the first movable part or piston ("strike mechanism") in the actuator. As described above, the movement of the first movable part or piston realized or driven by the movable squirrel-cage rotor is at least partially decoupled from the movement of the second movable part or piston in the actuator for driving nails or bolts, which reduces the rebound impact when installed in a solid substrate.

[0100] Another alternative embodiment of the handheld installation tool includes, for example, an electromagnetic drive according to WO 2012 / 079572A2 or WO 2014 / 056487A2 (as further described below), that is, an electromagnetic drive having at least one first coil and a second coil, the first coil being formed in a magnetic flux concentrator and the second coil being a movable coil. In this embodiment, the movable coil is formed in or on a movable element (piston, armature), which realizes the movement process of the first movable part or piston ("strike mechanism") in the actuator. As described above, the movement process of the first movable part or piston realized or driven by the moving coil is at least partially independent of the movement of the second movable part or piston in the actuator for driving the nail or bolt, which reduces the rebound impact.

[0101] With this embodiment, problem (A) is eliminated by the decoupling device.

[0102] Problem (B) can also be eliminated for electric drives with a moving coil by means of a decoupling device, since the short, limited stroke (relative to the installation stroke) of the electric drive allows the stranded wire to be significantly shorter and accordingly be subject to less inertial forces during operation; in addition, the movable coil can be supplied with electrical power via sliding contacts when necessary.

[0103] Problem (C) can also be solved by the decoupling device, since the deceleration of the armature ("piston") is now determined: due to the air cushion formed between the two pistons of the actuator 11 during the installation operation, for example, the "armature" or piston of the electric drive cannot experience a hard collision.

[0104] In another embodiment of an electric drive with movable coils, the drive can be reset in a simple manner: for driving / installing a nail, the coils are at least temporarily energized in the opposite direction (particularly preferably by means of capacitor discharge), so that repulsive forces act between the coils. Such reverse energization preferably also achieves mutual compensation of the electromagnetic remote fields formed, so that only lower requirements are placed on the shielding properties of the housing of the setting tool. Conversely, for resetting, the coils can be energized in the same direction, so that attractive (Lorentz) forces act between the coils.

[0105] Figure 7 In another embodiment, a decoupling device, such as Figure 1 An electric piston drive with a movable coil in combination with an actuator 11. This is a particularly high-power variant of the electric drive, which can accelerate a mostly non-metallic working piston with high efficiency by means of at least one movable coil and is characterized by a higher electrical efficiency and a lower mass of the installation tool at the same installation energy compared to the prior art. The following description should also not be understood as restrictive. Figure 7 The installation tool is symbolically shown in a "ready to fire" position.

[0106] Figure 7 The reference numerals in the figure represent:

[0107] 700: Power supply line (highly flexible stranded wire)

[0108] 710: Magnetic circuit (also called "flux concentrator"), i.e. a structure made of a soft magnetic material. The magnetic circuit particularly preferably has a saturation flux density of at least 1 T, preferably at least 1.5 T and more preferably at least 1.9 T and in particular has an effective conductivity of at most 10^6 S / m, more preferably at most 10^5 S / m and more preferably at most 10^4 S / m; different soft magnetic composite materials meet these prerequisites. Due to its brittleness, such soft magnetic materials are used for the magnetic circuit 701, and the composite material is partitioned professionally if necessary to avoid fractures in 701. That is, such partitioning is used to prevent the tensile strength (and preferably also called the yield limit) of the soft magnetic composite material from being locally exceeded during the installation process.

[0109] 711: First flat coil attached to the magnetic circuit ("support coil")

[0110] 720: Actuating piston, preferably formed completely or largely from plastic, in particular from a glass-fiber-filled liquid crystal polymer, which can be configured with at least one guide axis

[0111] 721: A second movable flat coil ("thrust coil") fixed to the drive piston or cast into the drive piston or injection-molded around the material of the drive piston

[0112] 730: A mounting piston with a piston rod. The driving energy is transmitted to the nail via the piston rod of the mounting piston 730.

[0113] 740: Substrates made of soft magnetic solid material, in particular ferromagnetic steel, for shielding (EMV, EMVU) and as heat sinks

[0114] 750: A tube made of CFK, especially used to relieve the tension of the magnetic circuit 710 and to center 710 and 780

[0115] 760: A tube made of an aluminum alloy which preferably has the highest possible electrical conductivity and which in the present case serves to shield electromagnetic alternating fields

[0116] 761: A soft magnetic material with a high saturation flux density, in particular ferromagnetic steel, constructed in a tubular shape. Used for shielding electromagnetic DC fields. A top view of the tube 761 is shown next to it, which has discrete gaps 762 distributed around the periphery, which in the present case can be used as gaps to reduce eddy currents.

[0117] 770: Installation tool housing

[0118] 780: Cylinders, for example of high-strength, easily polishable steel

[0119] 790: Carbon clad ring or other guide ring for mounting the piston rod of piston 730

[0120] In order to use Figure 7 The arrangement shown symbolically in FIG. 1 is used to drive or install a nail or a bolt into a substrate. First, a capacitor C1 is charged by a switching regulator SMPS (in a battery-operated installation tool, this is of course charged with the help of electrical energy from the one or more storage batteries BAT). The capacitor C1 should have the highest possible energy density and the lowest possible series resistance as well as a particularly high short-circuit strength. Corresponding capacitors are available as film capacitors specifically for pulse applications.

[0121] After the desired charging voltage has been reached via C1, the thyristor SCR can be activated for driving or installing the nail. The current now flows into the (flat) coil via the supply line 700. The two coils are preferably connected in series and connected in such a way that the currents in the two coils flow in opposite directions during the installation process, that is, the two coils repel each other. For the coils, in particular, Cu flat coils are considered in order to achieve the highest possible filling degree at a very low resistance.

[0122] The power supply line 700 can here pass directly through the piston 720 or its (rear) "guide shaft"; the power supply line is particularly preferably made of an aluminum alloy or copper, in particular in the form of a thin, highly flexible stranded wire, and is tension-relieved outside the piston 720, for example by means of carbon fibers or carbon fiber fabrics: it is important that the tension-relief structure mechanically connected in parallel with the power supply line is made of a material with sufficient tensile strength, that is, the material does not break under the given conditions and has a higher tensile modulus than the power supply line itself to be relieved. The tension-relief structure is preferably designed and dimensioned here so that the electrical conductor is protected from tensile stresses (occurring during or as a result of the installation process) that exceed the yield limit of the electrical conductor or even exceed the tensile strength. In addition, the material of the tension-relief structure should preferably have a high specific strength. Carbon fibers or their fabrics can meet these prerequisites. The driver piston 720 (first piston) is constructed to form an actuator 11 together with the mounting piston 730 (second piston) and the cylinder 780, i.e. as described above (for example according to Figure 1 ) decoupling device.

[0123] Preferred gas-dynamic seals in the form of pistons for labyrinth piston compressors Figure 7 In the embodiment, the guide elements which may be necessary are shown in the same manner and with similar details. The device for resetting the piston is also not shown together.

[0124] In practice, the invention can be implemented as follows: the graphics, including the circuit diagram, are converted into an FEM model and the geometry is parameterized, and the corresponding (material) properties are assigned to the individual components in the list of reference numerals. For the electrical components, real properties are assumed, that is, the circuit diagram is drawn in the model with a corresponding replacement circuit diagram. For the gas chamber, at least the van der Waals equation is established and solved in order to approximately calculate the corresponding gas forces acting on the surface; if necessary, the gas dynamics can also be taken into account. The number of turns of the first flat coil 711 and the movable second flat coil 721 is preferably the same, so that due to their series connection, the coils always generate (close to) the same magnetomotive force. Then, an optimization of the parameters is carried out ("parameter sweep analysis"), where structural requirements, such as manufacturing conditions, such as minimum wall thickness, describable (flat) wire thickness, etc., are taken into account at the same time; in other respects, (all) geometric parameters and the number of turns are changed, and the Pareto optimal state is also found while taking into account the prices of components, parts, materials and approval requirements (EMV, EMVU, etc.). Based on the optimal state thus found, the structural design of the machine structure can then be carried out, which may already differ from the FEM model due to problems of installability and manufacturing, may be more complex and may contain other components to be considered. Then, based on this structural design, the FEM optimization of the parameters is repeated. When carried out by a professional, this process can already produce a very high-performance installation tool after a few iterations. For example, a drive with a magnetic circuit with a diameter of only d=60 mm can easily achieve a drive energy of more than 500 J with an efficiency in the range of 50%. So far, combustion-operated installation tools, in particular powder-type installation tools, provide this energy range.

[0125] Other implementations are given below:

[0126] E1. A hand-held installation tool for driving nails and / or bolts into a substrate, the hand-held installation tool comprising:

[0127] - at least one electrochemical energy storage device 90, such as a battery / rechargeable battery, or a fuel cell

[0128] - At least one motor controller 80, preferably including an inverter

[0129] - at least one electric motor 70, preferably a brushless DC motor, more preferably with an axial magnetic flux distribution

[0130] - at least one speed reducer 60, preferably a multi-stage planetary gear transmission

[0131] - at least one tensioning device 50, preferably comprising a ratchet flywheel

[0132] - at least one locking device 40

[0133] at least one working gas reservoir 20 containing a working gas, which can also be a mixture of different pure gases, and

[0134] - at least one pneumatic actuator 10, wherein

[0135] The pneumatic actuator 10 comprises at least one piston with a piston rod 01 , which is in fluid communication with a working gas reservoir 20 and forms a gas spring together with the working gas reservoir 20 .

[0136] The actuator 10 has a stroke starting position and a stroke end position range, in which the gas spring is maximally tensioned at the stroke starting position, and in which the gas spring is less tensioned at the stroke end position range, characterized in that the working gas reservoir 20 is at a working gas pressure of greater than 10 bar, more preferably greater than 20 bar, more preferably greater than 40 bar, more preferably greater than 60 bar, more preferably greater than 80 bar, more preferably greater than 100 bar, more preferably greater than 120 bar when the gas spring is maximally tensioned, and wherein the volume of the working gas reservoir 20 is at least the same size as the maximum working volume of the pneumatic actuator 10, preferably twice the maximum working volume, more preferably greater than three times the maximum working volume, more preferably greater than four times the maximum working volume, in order to install the nail first The gas spring is tensioned in that the electric motor 70 is supplied with electric power from the energy storage device 90 by means of the motor controller 80 and the electric motor is controlled so as to drive the tensioning device 50 via the reducer 60, which in turn can convert the torque of the reducer 60 into a force so as to move the piston of the actuator 10 against the pressure of the working gas. After reaching the desired piston position, the actuator 10 is locked by the locking device 40, that is, the gas spring composed of the actuator 10 and the working gas storage device 20 is kept in a highly tensioned state, and in order to install the nail, the locking device 40 is released, so that the gas spring relaxes, that is, the actuator 10 is set in motion, and then the kinetic energy of the movable part of the actuator 10 (including the piston of the actuator) is used to drive the nail, and the nail is driven directly or by means of an additional striking mechanism 11.

[0137] E2. The installation tool according to E1 is characterized in that the size of the installation tool is designed so that during the installation operation, the maximum kinetic energy of the movable part of the actuator 10, in particular the maximum kinetic energy of all parts fixedly connected to the piston of the actuator 10, reaches at least half of the driving energy ultimately acting on the nail.

[0138] E3. A piston for a pneumatic actuator and in particular a gas spring, characterized in that the piston comprises a plurality of piston rings and a cavity is arranged between the piston rings in the axial direction, i.e. in the direction of movement of the piston, or the piston is constructed to have the cavity, which is preferably partially, but not completely, filled with a lubricant.

[0139] E4. A piston for a pneumatic actuator, in particular a gas spring, characterized in that the piston comprises a plurality of, for example two, pistons which are non-rigidly connected to one another and between which there is a fluid.

[0140] E5. A piston for a pneumatic actuator according to E4, characterized in that the fluid is a liquid lubricant.

[0141] E6. The piston for a pneumatic actuator according to E5, characterized in that the fluid is a non-Newtonian fluid, and in particular a shear-thinning fluid, and furthermore, the fluid preferably has thixotropic properties.

[0142] E7. A piston for a pneumatic actuator according to E6, characterized in that the non-Newtonian fluid and in particular the structurally viscous, preferably thixotropic fluid is achieved by dispersing one or more solid lubricants, preferably hexagonal boron nitride and / or graphite and / or MoS2, in a liquid lubricant, and / or dissolving one or more oligomers or polymers in a liquid lubricant.

[0143] E8. Pneumatic actuator, comprising a cylinder and a piston according to one or more pistons in accordance with E3 to E7, characterized in that the cylinder is configured to include a valve seat, and the piston is configured to serve as a shut-off element for the valve seat or to have a corresponding shut-off element, so that the piston and cylinder together form a valve, and the valve can be closed by pressing the piston and therefore the shut-off element against the valve seat formed by the cylinder or attached to the cylinder using sufficient external force.

[0144] E9. A striking mechanism for an installation tool, characterized in that the kinetic energy of the first piston of a piston driver is transmitted to a movable part, such as a second piston, and a nail or a bolt is driven entirely or mainly with the aid of the kinetic energy of the movable part, and the first piston and the movable part are non-rigidly connected to each other, whereby the first piston and the movable part are decoupled over their stroke length.

[0145] E10. A striking mechanism for an installation tool, comprising at least a first piston and a second piston and a cylinder, wherein the pistons are arranged opposite to each other, i.e., in the cylinder as in an opposed-piston engine, and as a sealing mechanism, a preferably gas-powered seal, such as a labyrinth seal, can be provided instead of a piston ring, and the first piston is driven, momentum is transferred to the second piston through the gas located between the pistons, and the kinetic energy of the second piston can be used, for example via a piston rod, to drive nails and / or bolts or for hammering drill holes.

[0146] E11. The striking mechanism according to E10 is characterized in that a reset device is provided for the second piston.

[0147] E12. The striking mechanism according to E10 or E11 is characterized in that the working surface of each piston and / or cylinder is hard chrome-plated.

[0148] E13. Hand-held installation tool, including at least:

[0149] A piston drive arranged axially displaceably in the setting tool, the piston drive having one or more stroke start positions and a stroke end position range

[0150] - a piston drivable by a piston driver, said piston preferably having at most a quarter of the mass of the piston driver

[0151] - an openable locking device which can fix the piston drive in one or more stroke start positions

[0152] - shock absorbers, such as hydraulic shock absorbers

[0153] - a reset device, such as a reset spring, which can return the piston driver from the end-of-stroke position range to the start-of-stroke position relative to the installation tool, characterized in that during the installation operation, the locking mechanism is opened or can be opened, so that the piston driver can move from the start-of-stroke position in the direction of the end-of-stroke position range by a rebound that can be experienced by the piston driver, and this return stroke of the piston driver can be braked by the shock absorber, and the piston driver is preferably braked by the shock absorber only after a return stroke of a specific return distance, and the return distance is such that the nail or bolt has been mostly or preferably completely driven in before the shock absorber takes effect and the driver is braked on the return stroke.

[0154] E14. A handheld installation tool according to E13, characterized in that, in the reference system of the installation tool, the extended path of the center of gravity of the piston or these pistons is parallel to the extended movement path of the movable piston driver.

[0155] E15. A handheld installation tool according to E13 or E14, characterized in that the extended path of the center of gravity of the piston or these pistons passes through the center of gravity of the piston driver at least during driving a nail or a bolt, which in the present case means that during driving, the minimum distance of the extended path from the center of gravity of the driver is always at least five times, but preferably more than ten times, smaller than the minimum distance of the extended path from the center of gravity of the entire installation tool.

[0156] E16. A handheld installation tool according to one or more of E13 to E15, characterized in that the installation tool has at least one handle, and the handle is rotatably mounted relative to a part of the installation tool, and the piston driver is axially movably arranged in or on the installation tool, wherein at least one mechanical buffer, such as a hydraulic shock absorber or a polymer buffer, is provided to buffer the rotational movement between the handle and the component, and the handle is rotatably mounted on the component, wherein a locking device can be provided to block the rotational movement when no installation operation is performed.

[0157] E17. An installation tool comprising a striking mechanism according to one or more of E9 to E13, wherein the piston driver is an electric driver and the mass accelerated by the piston driver can be understood as a piston, or includes the mass of the first movable part of the striking mechanism according to E9.

[0158] E18. A handheld installation tool according to E17, characterized in that the drive is an electric drive, which includes at least one excitation coil and at least one active second coil or active squirrel cage winding, wherein the second coil or squirrel cage winding can preferably be arranged on a component made of soft magnetic material that can move along the axis of motion, and the soft magnetic material preferably has a saturation magnetic flux density of at least 1.5T and an effective specific conductivity of preferably at most 10^6S / m.

[0159] E19. A handheld installation tool for driving a nail or a bolt into a substrate, the handheld installation tool comprising: a driver 600, preferably a gas spring driver or an electric driver, the driver driving an installation piston 610 for driving a nail or a bolt into the substrate; characterized in that the installation piston 610 has at most one quarter of the mass of the driver 600.

[0160] E20. A handheld installation tool according to E19, wherein the driver 600 is axially movably arranged in the installation tool, preferably on a guide element 690 .

[0161] E21. The handheld installation tool according to E20 comprises: an openable locking device 620, which is configured to fix the driver in one or more stroke starting positions; a shock absorber 640, such as a hydraulic shock absorber; a reset device, such as a reset spring, which is configured to return the driver from the stroke end position range to the stroke starting position relative to the installation tool; wherein, during the installation operation, the locking mechanism 620 is opened or can be opened, so that the driver 600 can move from the stroke starting position A toward the stroke end position range through rebound performed by the driver, wherein this return stroke of the driver 600 can be braked by the shock absorber 640, wherein the driver 600 is preferably braked by the shock absorber 640 only after a return stroke of a specific return distance s', and the return distance is such that the nail or bolt has been mostly or preferably completely driven in before the shock absorber 640 takes effect and brakes the return stroke of the driver.

Claims

1. A hand-held installation tool for driving a nail or a bolt into a substrate, the hand-held installation tool comprising: a driver that drives an actuator (11) for driving the nail or bolt into the substrate, and a decoupling device which at least partially decouples a first movement process of a first movable part or piston (111) in the actuator (11) driven by the driver from a second movement process of a second movable part or piston (112) in the actuator (11) for driving the nail or bolt; The drive is an electric drive, wherein the electric drive comprises at least a first coil (711) and a second coil (721), wherein the first coil (711) is formed on and / or in a flux concentrator (710), and the second coil (721) is a movable coil, wherein the movable coil is formed in or on a movable element (720), wherein the movable element realizes the movement process of the first movable part or the piston (111) in the actuator (11), and the second coil (721) can be electrically connected via a twisted wire or a sliding contact.

2. The handheld installation tool according to claim 1, wherein: The first movable part or piston (111) is not rigidly connected to the second movable part or piston (112).

3. The handheld installation tool according to claim 1, wherein: A compressible fluid exists between the first movable part or piston (111) and the second movable part or piston (112).

4. The handheld installation tool according to claim 1, wherein: The first movable part or piston (111) has a first stroke length and the second movable part or piston (112) has a second stroke length, the first stroke length and the second stroke length being decoupled.

5. The handheld installation tool according to claim 1, wherein: The actuator (11) further comprises a cylinder, wherein: The first movable part or piston (111) and the second movable part or piston (112) are arranged opposite each other in the cylinder, and at least one piston seal is formed in the cylinder.

6. The handheld installation tool according to claim 5, wherein: The piston seal comprises at least: - one or more piston rings, and / or - Gas powered seals.

7. The handheld installation tool according to claim 1, wherein: The resetting device is configured for the second movable part or piston (112).

8. The handheld installation tool according to claim 1, wherein: The first movable part or piston (111), the second movable part or piston (112) and / or the cylinder working surface are hard chrome plated.

9. The handheld installation tool according to claim 1, further comprising: A further actuator (10) in the drive, wherein the further actuator (10) implements the first movement process in the actuator (11).

10. The handheld installation tool according to claim 9, wherein: The second movable part or piston (112) in the actuator (11) is mounted to a travel independently of the travel of the other actuator (10).

11. The handheld installation tool according to claim 1, wherein: During a mounting operation, the current in the first coil (711) flows at least temporarily in a direction opposite to the current in the second coil (721), causing the two coils to repel each other.

12. The handheld installation tool according to claim 1, wherein: The second movable part or piston (112) has at most one quarter of the mass of the actuator (600) as a mounting piston (610).

13. The handheld installation tool according to claim 1, wherein: The driver (600) is arranged in the installation tool so as to be axially movable.

14. The handheld installation tool according to claim 1, further comprising: an openable locking device (620) configured to secure the actuator in one or more stroke start positions; Shock absorber (640), a reset device configured to move the actuator relative to the installation tool from the end-of-stroke position range back to the start-of-stroke position; wherein, during the installation operation, the openable locking device (620) is opened or can be opened, so that the driver (600) can move from the stroke starting position (A) towards the stroke end position range due to the rebound experienced by the driver, wherein this return stroke of the driver (600) can be braked by the shock absorber (640), and the driver (600) is braked by the shock absorber (640) only after a return stroke of a specific return distance (s'), and the return stroke distance is such that the nail or bolt is mostly or completely driven in before the shock absorber (640) takes effect and brakes the return stroke of the driver.

15. The handheld installation tool according to claim 1, wherein: In the reference system of the installation tool, the extended path of the center of gravity (S1) of the second movable part or piston (112) is parallel to the extended movement path of the movable drive.

16. The handheld installation tool according to claim 15, wherein: At least during the driving of the nail or bolt, the extended path of the center of gravity (S1) of the second movable part or piston (112) passes as close as possible to the center of gravity (S2) of the driver, and during the installation operation, the minimum distance of the extended path from the center of gravity (S2) of the driver is always at least five times smaller than the minimum distance of the extended path from the center of gravity of the entire installation tool.

17. The handheld installation tool according to claim 1, wherein: The installation tool includes at least one handle (630), which is rotatably mounted relative to a part of the installation tool, and an axially movable drive is arranged in or on the installation tool, wherein at least one mechanical buffer (641) is provided to suppress the rotational movement between the handle (630) and the component, and the handle is rotatably mounted on the component, wherein at least one device (621) can be provided to block the rotational movement when no installation operation is performed.

18. The handheld installation tool according to claim 3, wherein: The compressible fluid is air.

19. The handheld installation tool according to claim 6, wherein: The gas dynamic seal is a gas dynamic seal of the labyrinth piston compressor type.

20. The handheld installation tool of claim 16, wherein: During the installation operation, the minimum distance of the extended path from the center of gravity (S2) of the driver is always more than ten times smaller than the minimum distance of the extended path from the center of gravity of the entire installation tool.

21. The handheld installation tool of claim 14, wherein: The shock absorber (640) is a hydraulic shock absorber.

22. The handheld installation tool of claim 14, wherein: The resetting device is a resetting spring.

23. The handheld installation tool of claim 17, wherein: The at least one mechanical buffer (641) is a hydraulic shock absorber or a polymer buffer.

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