Fastener driving tool

Abstract

The invention relates to a fastener driving tool (1) for driving a fastening element (2) in the form of a nail into an anchoring base which is made of wood for example. The invention proposes separating a piston (11) from a clamping device (18) while driving in the fastening element (2) so that a gas pressure solely drives the fastening element (2) and is not used to move the clamping device (18).

Description

[0001] Description

[0002] Setting tool

[0003] The invention relates to a setting tool for driving a fastening element into an anchor base with the features of the preamble of claim 1.

[0004] The setting tool is preferably a pusher, but a gun or other setting tool is also possible. The fastening element is usually a nail.

[0005] A setting tool for driving a nail into an anchor base is known from patent application US 2021 / 0 146 517 A1. The known setting tool has a piston-cylinder unit as an energy storage device. The piston is moved into a cylinder by an electric motor via a cable pull, thereby compressing air in the cylinder. To drive the nail into the anchor base, a cable of the cable pull is released from a cable pulley of the cable pull, whereupon the compressed air in the cylinder pushes the piston out of the cylinder, whereby the piston moves the nail axially in a driving direction.

[0006] The object of the invention is to minimize the forces exerted by a setting tool that oppose the driving of a fastener into an anchor base. This does not apply to masses that must be accelerated to drive the fastener.

[0007] This object is achieved according to the invention by the features of claim 1. The setting tool according to the invention has a driver for driving the fastening element into an anchor base. The anchor base is, for example, a component made of wood, concrete or masonry, this list being exemplary and not exhaustive. The driver is movable along and on an axis of the setting tool. In addition, the setting tool has an energy storage device for moving the driver from a rear end position in a driving-in direction to a front end position, a tensioning device for tensioning the energy storage device and a transmitter. The transmitter is displaceable parallel to the axis and arranged offset parallel to this axis. In particular, the transmitter is coupled to the driver in a parallel offset, i.e. the transmitter acts on the driver in a parallel offset to the axis.The transmitter transmits a movement of the tensioning device for tensioning the energy storage device to the driver. During this movement, the energy storage device is tensioned, in particular by the driver. In the front end position, the driver is coupled to the transmitter - preferably automatically - in such a way that the driver moves with the transmitter from the front end position in the tensioning direction to the rear end position and the energy storage device is tensioned. In the rear end position, the driver is separated from the transmitter - preferably also automatically - in such a way that the driver moves independently of the transmitter and the tensioning device when moving from the rear end position in the driving-in direction to the front end position.

[0008] The term "driver" refers to an element of the setting tool according to the invention that is moved in the driving direction by the tensioned energy storage device to drive the fastening element into the anchor base and that moves the fastening element in the driving direction. In particular, the driver is in direct contact with the fastening element. The driver can also be or comprise an assembly consisting of several components. The driver is therefore the element that transfers energy or movement from the energy storage device to the fastening element to drive the fastening element into the anchor base and acts on or moves it in the driving direction.

[0009] The energy storage device stores energy for driving the fastener into the anchor base in essentially any desired form and transfers this energy, at least in part, to the driver. The energy storage device itself or a converter converts the stored energy into movement, i.e., kinetic energy, unless the energy storage device stores the energy as kinetic energy. Storing energy in the energy storage device is referred to here as "tensioning," and discharging or transferring energy from the energy storage device to the driver is referred to as "relaxing" the energy storage device.

[0010] The energy storage device is or comprises, for example, a spring element, in particular a helical compression spring or a piston-cylinder unit as a gas spring. A spring element or a helical compression spring are mechanically tensioned. If the energy storage device is a piston-cylinder unit, a piston is moved into a cylinder of the piston-cylinder unit for tensioning in such a way that a gas contained in the cylinder is compressed. Other energy storage devices are possible. For tensioning, the tensioning device moves the transmitter, which is coupled to the driver in the front end position of the driver, in such a way that the driver moves with the transmitter from the front end position in the tensioning direction to the rear end position, whereby the energy storage device is tensioned, in particular by the driver.In the rear end position of the driver, the driver is separated from the transmitter, allowing the driver to move from the rear end position in the driving direction to the front end position independently of the tensioning device and the transmitter. As a result, the energy storage device moves the driver without the tensioning device and the transmitter when driving the fastener into the anchor base, eliminating the need to use energy from the energy storage device to move the tensioning device or transmitter when driving the fastener.

[0011] The invention has the advantage that the transmitter and the tensioning device are driven neither by the driver nor by the energy storage device when driving the fastening element into the anchor base, whereby no energy from the energy storage device has to be used for a movement, in particular of the tensioning device, during the driving-in process and is therefore not available for the driving-in process.

[0012] The fact that the transmitter has a parallel offset to the axis means that the transmitter does not intersect the axis, but is arranged around it. The driver, when coupled to the transmitter, is arranged radially to the axis within the transmitter. The parallel offset, and the fact that the transmitter is coupled to the driver, particularly offset parallel to the axis, or engages it, has the advantage that the axial length of the setting tool according to the invention can be kept short.

[0013] Preferably, the driver is automatically coupled to the transmitter in its forward end position and / or automatically separated from the transmitter in its rear end position. This means that the driver and transmitter do not need to be manually coupled and / or separated by a user. In particular, separating the driver from the transmitter in the rear end position triggers the driving process. This means that after separating the driver from the transmitter, the tensioned energy storage device transfers energy to the driver, in particular only to the driver, without any further action, thereby loading or moving the driver forward in the driving direction toward the front end position.

[0014] Preferably, the transmitter is separated from the driver by a joint movement of the transmitter and driver in the clamping direction. This means that to separate the driver from the transmitter, both are moved together to the rear end position, thus separating them from each other, especially automatically.

[0015] To automatically separate the driver from the transmitter, in one embodiment of the invention, the setting tool has a disengagement surface that runs obliquely to the axis of the setting tool and that the transmitter reaches shortly before the driver reaches its rear end position. The disengagement surface is arranged and aligned such that it releases the transmitter from the driver when the transmitter is moved to its rear end position. The driver is now movable forward in the driving direction to its front end position independently of the transmitter and is moved or at least acted upon in the driving direction by the energy storage device.

[0016] One embodiment of the invention provides a pulley block as a tensioning device or as part of the tensioning device for tensioning the energy storage device, wherein the pulley block transmits a tensioning force from the tensioning device to the transmitter. A pulley block is understood here to be a mechanical device with a traction mechanism that is guided around at least one deflection point and that simultaneously transmits a force and reduces a travel distance, i.e., a special form of mechanical transmission. The traction mechanism is, for example, a type of rope that preferably stretches little or not at all under tensile stress and that can be guided and wound around the deflection point in a slack-flexible manner.

[0017] In embodiments of the invention, the tensioning device engages the transmitter at a plurality of engagement points distributed evenly or unevenly around a circumference and spaced from the axis of the setting tool. The engagement points can be arranged in a radial plane to the axis of the setting tool or offset from one another in the direction of the axis of the setting tool. For example, the tensioning device has two or more pulleys that engage the engagement points of the transmitter distributed around the circumference. Also possible are a plurality of tensioning devices that engage the engagement points on the transmitter offset from one another in the circumferential direction. Preferably, the engagement points of the tensioning device on the transmitter are arranged in such a way that a symmetrical force introduction from the transmitter to the driver results when tensioning the energy storage device.This means that the clamping force or forces exerted by the clamping device when tensioning the energy storage device balance each other with respect to a tilting moment that they generate due to the force being applied at a distance from the axis of the setting tool. A tilting moment about a radial axis relative to the axis of the setting tool on the driver is avoided.

[0018] One embodiment of the invention provides two pulley blocks as components of the tensioning device, the traction means of which extend in tangential planes to the axis of the setting tool, i.e., are offset parallel to the axis. The tangential planes are planes parallel to the axis of the setting tool and are radially spaced from the axis of the setting tool. Preferably, the traction means of the two pulley blocks extend in tangential planes to the axis of the setting tool that are arranged opposite one another and parallel to the axis of the setting tool.

[0019] When the energy storage device is tensioned, the tensioning device moves the transmitter in the tensioning direction to the rear end position, where the transmitter is separated from the driver. In order to move the transmitter back in the driving direction to the front end position, where it is recoupled to the driver for a renewed tensioning of the energy storage device, one embodiment of the invention provides that the transmitter is movable in the driving direction independently of the tensioning device. Preferably, the setting tool has a return spring element that is connected to the transmitter, which is tensioned when the transmitter moves in the tensioning direction, and which moves the transmitter back in the driving direction to the front end position after separation from the driver.

[0020] The features and combinations of features, embodiments and configurations of the invention mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or drawn in a figure can be used not only in the respective combination specified or drawn, but also in principle any other combinations or individually. Embodiments of the invention are possible which do not have all the features of a dependent claim. Individual features of a claim can also be replaced by other disclosed features or combinations of features. Embodiments of the invention which do not have all the features of the exemplary embodiment, but basically any part of the identified features of the exemplary embodiment, are possible.

[0021] The invention is explained in more detail below using an embodiment shown in the drawing.

[0022] They show:

[0023] Figure 1 is a schematic axial sectional view of a setting tool according to the invention;

[0024] Figure 2 is a perspective view of parts of a driving mechanism of the setting tool of Figure 1 with a driver in a front end position;

[0025] Figure 3 shows the drive mechanism from Figure 2 with the driver just before a rear

[0026] end position; and

[0027] Figure 4 is an enlargement of Figure 3.

[0028] The setting tool 1 according to the invention, shown in Figure 1, is intended for driving a fastening element 2, for example a nail, into an anchor base (not shown) made of, for example, wood. The setting tool 1 has an axis 3 and a housing 4 that encloses the axis 3 and can be understood as cylindrical with a frustoconical taper towards a front end. The housing 4 has a handle 5 for holding the setting tool 1 with one hand, which is arranged on the housing 4 almost radially to the axis 3, slightly behind a longitudinal center of the housing 4. At an end of the handle 5 remote from the axis 3, a battery 6 for supplying power to an electric motor 7 of the setting tool 1 is detachably arranged.

[0029] Near the front end of the housing 4, the setting tool 1 has a magazine 8 for the fastening elements 2, from which the nails forming the fastening elements 2 are individually fed coaxially onto the axis 3 of the setting tool 1 by means of a magazine spring 9.

[0030] Arranged coaxially in the housing 4 is a piston-cylinder unit 10, the piston 11 of which has a coaxial plunger 12 that projects forward, i.e. in the direction of the nail that forms the fastening element 2 and is moved from the magazine 8 onto the axis 2. In the exemplary embodiment, the piston 11 is a hollow, cylindrical piston that is closed at its front end, which has the plunger 12, and is axially displaceable in a cylinder 13 of the piston-cylinder unit 10. The cylinder 13 of the piston-cylinder unit 10 is arranged coaxially and fixedly in the housing 4 of the setting tool 1. Together with the plunger 12, the piston 11 forms a driver 14 of the setting tool 1 for driving the fastening element 2 into the anchor base (not shown). Alternatively, it would also be possible for the plunger 12 alone to form the driver, which is acted upon, for example, by a helical compression spring.

[0031] The piston-cylinder unit 10 forms a tensionable energy storage device 15 of the setting tool 1 according to the invention for driving or moving the driver 14 from a rear end position in a driving direction 16 along and on the axis 3 to a front end position for driving the fastening element 2 into the anchor base (not shown). The driving direction 16 is shown in the figures with an arrow, as is a tensioning direction 17 opposite it. In the exemplary embodiment, the setting tool 1 with the piston-cylinder unit 10 has a pneumatic or gas pressure energy storage device 15, which is tensioned into the cylinder 13 by a displacement of the piston 11, whereby air or gas is compressed in the cylinder 13, the pressure of which is used to move the piston 11 to drive the fastening element 2 into the anchor base.The compression of the air or gas in the cylinder 13 of the piston-cylinder unit 10 is referred to here as “tensioning” the energy storage device 15 and can generally also be understood as storing energy in the energy storage device 15.

[0032] The invention is not limited to the piston-cylinder unit 10 as energy storage 15, but the setting tool 1 according to the invention can also have another energy storage, in particular a likewise coaxially arranged helical compression spring as the mechanical energy storage in this case (not shown).

[0033] To tension the energy storage device 15, i.e., to store energy in the energy storage device 15, the setting tool 1 according to the invention has a tensioning device 18 that tensions the energy storage device 15 by moving the piston 11 from the front end position in the tensioning direction 17 opposite the driving direction 16. The tensioning device 18 displaces the piston 11 into the cylinder 13, thereby compressing the air or gas in the cylinder 13 and thereby tensioning the energy storage device 15. In the exemplary embodiment, the tensioning device 18, shown in Figures 2 to 4, has two pulley blocks 19 that have cables as traction means 20 that run in two tangential planes opposite each other with respect to the axis 3 of the setting tool 1. The tangential planes are planes parallel to an axial plane of the axis 3, laterally adjacent to and radially outside the piston-cylinder unit 10.In the exemplary embodiment, the two tangential planes in which the traction means 20 of the two pulley blocks 19 run are opposite one another with respect to the piston-cylinder unit 10.

[0034] The ropes forming the traction means 20 of the two pulley blocks 19 can each be wound onto a pulley 21, which are arranged coaxially and rigidly with one another on a common shaft 22. A rotational axis 23 of the two pulleys 21 runs tangentially to the axis 3 of the setting device 1. The shaft 22 with the two pulleys 21 is rotary-driven by means of the electric motor 7 via a spur gear 24 with a first pinion 39 that meshes with a first gear 25 that is coaxial and rotationally fixed with a second pinion 40 that meshes with the second gear 26. The first pinion 39 is rotationally fixed to a motor shaft of the electric motor 7 and can be driven in rotation by the electric motor, and the second gear 26 is rotationally fixed to the shaft 22 of the two pulleys 21, such that the shaft 22 and the two pulleys 21 rotate together with the second gear 26 of the spur gear 24.The electric motor 7 is arranged parallel to the two pulleys 21, i.e. also tangential to the axis 3 of the setting device 1.

[0035] In the exemplary embodiment, the electric motor 7 and the cable pulleys 21 are located below the piston-cylinder unit 10, i.e., in the region of a transition from the housing 4 to the handle 5, as can be seen in Figure 1. In Figures 2 to 4, the electric motor 7 and the cable pulleys 21 are drawn above the piston-cylinder unit 10 for the sake of clarity, and the electric motor 7 is indicated by dashed lines. Another arrangement of the electric motor 7 is possible; in particular, the electric motor 7 can be arranged, for example, by means of a bevel gear or a worm gear, radially to the axis of rotation 23 of the cable pulleys 21 and parallel to or in the handle s (not shown).

[0036] From the cable pulleys 21, the ropes forming the traction means 20 of the pulley blocks 19 each run around a housing-fixed deflection pulley 27, from the housing-fixed deflection pulleys 27 parallel to the axis 3 of the setting tool 1 forwards around axially parallel movable deflection pulleys 28, around which the traction means 20 are deflected back by 180° axially parallel to the rear, where the traction means 20 are fixed in the housing 4 of the setting tool 1 at approximately the level of the axis of rotation 23 of the cable pulleys 21, viewed in the direction of the axis 3. A first common axis of rotation 29 of the housing-fixed deflection pulleys 27 runs parallel to the axis of rotation 23 of the cable pulleys 21 and thus tangential to the axis 3 of the setting tool 1. By deflecting the traction means 20 around the movable deflection rollers 28, a tensile force of the pulley blocks 19 is increased; in the exemplary embodiment, the tensile force is doubled, i.e. the tensile force of the pulley blocks 19 and thus a tensioning force of the tensioning device 15 is increased or translated.

[0037] A second common axis of rotation 30 of the movable deflection rollers 28 runs parallel to the first common axis of rotation 29 of the movable deflection rollers 28 and radially intersects the axis 3 of the setting tool 1. The movable deflection rollers 28 are rotatably mounted on transformers 31, which are offset parallel to the axis 3 and arranged opposite one another laterally next to the piston 11 of the piston-cylinder unit 10. They are guided in the housing 4 of the setting tool 1 by sliding guides 32 parallel to the axis 3 of the setting tool 1. For clarity of illustration, parts of the sliding guides 32 that conceal the transformers 31 are not shown.

[0038] The transformers 31 have radially inward-projecting claws 33 on their front sides, which rest against the closed front end of the piston 11 to tension the energy storage device 15. To tension the energy storage device 15, the transformers 31 are pulled into the rear end position in the tensioning direction 17 by winding the traction means 20 onto the cable pulleys 21 with the pulley blocks 19 of the tensioning device 18. They push the piston 11 into the cylinder 13, thereby compressing the air or gas in the cylinder 13 and thereby tensioning the energy storage device 15. The energy storage device 15 is thus tensioned from the front end position in the tensioning direction 17 opposite to the driving direction 16 into the rear end position by the movement of the driver 14, which the piston 11 forms together with the plunger 12.

[0039] Via the claws 33 of the transmitter 31, the clamping device 18 engages the driver 14 at points distributed over a circumference and at a distance from the axis 3 of the setting tool 1. In the exemplary embodiment, the clamping device 18 engages the driver 14 via the claws 33 of the transmitter 31 at two circumferential points radially opposite one another with respect to the axis 3, both eccentrically, namely at a distance from the axis 3 of the setting tool 1, and symmetrically to the axis 3. As a result, tilting moments about imaginary radial axes or transverse axes of the piston 11 forming the driver 14 are compensated radially to the axis 3 of the setting tool 1, i.e. the driver 14 is moved torque-free by the clamping device 18 in the clamping direction 17 into the rear end position during and for clamping the energy storage device 15.

[0040] Two pairs of pins 34 each protrude from the transmitters 31, coaxially in the tangential planes to the axis 3 of the setting tool 1 according to the invention, upwards, i.e., away from the handle 5, and downwards, i.e., in the direction in which the handle 5 protrudes. The pins 34 interact with disengagement surfaces 35, which are arranged fixedly in the housing 4 of the setting tool 1. The disengagement surfaces 35 extend obliquely to the axis 3 of the setting tool 1, with the distance from the axis 3 increasing from front to rear, such that the pins 34 of the transmitters 31 come into contact with the respectively assigned disengagement surfaces 35 shortly before the transmitters 31 reach the rear end position. When the transmitters 31 move further to the rear end position, the release surfaces 35 move the transmitters 31 on the pins 34 radially away from the axis 3 of the setting tool 1, such that the claws 33 are disengaged from the piston 11 forming the driver 14.In this way, the driver 14 is automatically separated from the transmitters 31 in the rear end position and is accelerated and moved forward by the air pressure or gas pressure in the cylinder 13 of the piston-cylinder unit 10, and in doing so moves the fastening element 2, which is arranged coaxially to the axis 3, forward out of the setting tool 1 via the plunger 12, whereby the fastening element 2 can be driven into the anchor base (not shown).

[0041] In the exemplary embodiment, the release surfaces 35 are straight, but they can also be curved, for example.

[0042] By separating the driver 14 from the transmitters 31 in the rear end position of the driver 14, the driver 14 is also separated from the tensioning device 18 and its pulley blocks 19, whose traction means 20 are deflected around the movable deflection rollers 28 of the transmitters 31 and engage the driver 14 indirectly via the transmitters 31 when the claws 33 are engaged with the driver 14 during the movement of the transmitters 31 together with the driver 14 in the tensioning direction 17. During its movement 14 in the driving direction 16 after separation from the transmitters 31, the driver 14 moves independently of the tensioning device 18 with its pulley blocks 19.An energy transferred from the energy storage device 15 to the piston 11 forming the driver 14 when the energy storage device 15 is released is therefore completely available for moving the driver 14 and the fastening element 2 and no energy from the energy storage device 15 is lost for moving the tensioning device 18 with the pulleys 19.

[0043] Return spring elements 36 of a return system engage the transmitters 31. These elements are tensioned rearward when the transmitters 31 move in the tensioning direction 17 and, after the transmitters 31 are separated from the driver 14 in the rear end position, move the transmitters 31 forward again in the driving direction 16 to the front end position. In the exemplary embodiment, the return spring elements 36 are helical tension springs that engage the transmitters 31 via cables as connecting tension means 37 of the return system, which are deflected around second housing-fixed deflection rollers 38 of the return system.

[0044] Coil tension springs as return spring elements 36 are not mandatory for the invention; other return spring elements or return systems are also possible (not shown). Likewise, it is not mandatory for the invention that the return spring elements 36 act indirectly on the transmitters 31 via the tension means 37 of the return system; the return spring elements 36 can also act directly on the transmitters 31 (not shown). In the exemplary embodiment, the tension means 37 of the return spring elements 36 run in the same tangential planes as the tension means 20 of the pulley blocks 19 of the tensioning device 18, which is also not mandatory for the invention.

[0045] The tensioning means 37 of the return system, tensioned by the return spring elements 36, act on the transducers 31, which are moved outward by the release surfaces 35, at an angle inward, i.e., with a force component in the direction of the axis 3 of the setting tool 1. As a result, the transducers 31 are moved inward in the front end position in the direction of the axis 3, causing their claws 33 to re-engage with the driver 14 in the front end position. As a result, the driver 14 is automatically coupled to the transducers 31 in the front end position. List of reference symbols

[0046] Setting tool Setting tool 29 First common axis of rotation Fastening element 30 Second common axis of rotation Axis 31 Transformer Housing 32 Sliding guide Handle 33 Claw Accumulator 34 Pin Electric motor 35 Release surface Magazine 36 Return spring element Magazine spring 37 Traction means of the return system Piston-cylinder unit 38 Deflection pulley of the return system Piston 39 First pinion Tappet 40 Second pinion Cylinder Driver Energy storage Driving direction Tensioning direction Tensioning device Pulley Traction means Cable pulley Shaft Axis of rotation of the cable pulleys 21 Spur gear First gear Second gear Housing-fixed deflection pulley Movable deflection pulley

Claims

Claims: Setting device (1) for driving a fastening element (2) into an anchor base, comprising a driver (14) displaceable along an axis (3) of the setting device (1), the driver being movable by a tensioned energy storage device (15) in a driving direction (16) from a rear end position to a front end position along the axis (3) such that, during its movement in the driving direction (16), the driver (14) moves the fastening element (2) in the driving direction (16) along the axis (3) of the setting device (1), wherein the energy storage device (15) is tensioned by a movement of the driver (14) in a tensioning direction (17) opposite to the driving direction (16) along the axis (3) of the setting device (1), characterized in that the setting device (1) has a transducer displaceable parallel to its axis (3) and offset parallel to this axis (3). (31) and a clamping device (18),which moves the transmitter (31) to tension the energy storage device (15) in the tensioning direction (17), and that the transmitter (31) is coupled to the driver (14) in the front end position of the driver (14) such that the transmitter (31) takes the driver (14) with it during its movement in the tensioning direction (17) and tensions the energy storage device (15), and that in the rear end position of the driver (14) the transmitter (31) is separated from the driver (14) such that the driver (14) moves in the driving direction (16) independently of the transmitter (31) and the tensioning device (18) after separation from the transmitter (31). Setting device (1) according to claim 1, characterized in that the transmitter (31) is automatically disconnected from the driver (14) in the rear end position and / or that the transmitter (31) is automatically coupled to the driver (14) in the front end position. Setting device (1) according to one of the preceding claims, characterized in that the transmitter (31) is separated from the driver (14) by a joint movement of the transmitter (31) and the driver (14) in the clamping direction. Setting device (1) according to claim 2 or claim 3, characterized in that the setting device (1) has a disengagement surface (35) extending obliquely to its axis (3), which moves the transmitter (31) out of engagement with the driver (14) upon reaching the rear end position and thereby separates it from the transmitter (31). Setting device (1) according to one or more of claims 1 to 4, characterized in that the clamping device (18) has a pulley (19) for clamping the energy storage device (15), wherein the pulley (19) is coupled to the transmitter (31) such that it translates a clamping force of the clamping device (17) to move the transmitter (31).Setting device (1) according to claim 5, characterized in that the clamping device (18) engages the driver (14) at several points distributed around its circumference at a distance from the axis (3) of the setting device (1). Setting device (1) according to claim 6, characterized in that the clamping device (18) engages the driver (14) symmetrically with respect to the axis (3) of the setting device (1) with respect to the force application, such that the clamping force does not generate a tilting moment on the driver (14). Setting device (1) according to one or more of claims 5 to 7, characterized in that the clamping device (18) has two pulleys (19) whose tension members (20) extend in tangential planes to the axis (3) of the setting device (1). Setting device (1) according to one or more of the preceding claims, characterized in that the driver (31) is movable in the driving direction independently of the clamping device (18). Setting device (1) according to claim 9, characterized in that the setting device (1) has a return spring element (36) for the transmitter (31) which is tensioned when the transmitter (31) is moved in the tensioning direction (17) and which moves the transmitter (31) in the driving direction (16) after separation from the driver (14) at the rear end position.

Images