EP2416929A1

EP2416929A1 - Fuel-operated setting device

Info

Publication number: EP2416929A1
Application number: EP10710220A
Authority: EP
Inventors: Willi Haug; Meinrad Zeh; Alexander Stumpp; Andreas Van Ostaeyen
Original assignee: Fischerwerke GmbH and Co KG
Current assignee: Fischerwerke GmbH and Co KG
Priority date: 2009-04-08
Filing date: 2010-03-17
Publication date: 2012-02-15
Also published as: CN102387897A; WO2010115506A1; DE102009016946A1

Abstract

The invention relates to a fuel-operated setting device (1) for driving bolts (2) into foundations (3), said device comprising a driving piston (4), a piston head guiding element (9), a piston rod guiding element (8), and a combustion chamber (15) with an adjustable length. The aim of the invention is to provide such a setting device with a simple, robust structure and, at the same time, the capacity to regulate the power just before the bolt is placed on the foundation (3), without requiring further movement. To this end, the piston head guiding element (9) and the piston rod guiding element (8) can be moved in relation to each other, and the length of the combustion chamber (15) can be determined by adjusting its path of displacement V.

Description

description

Internal combustion setting device

The invention relates to a combustion-powered setting tool for driving bolts in a substrate with the features of claim 1.

Such setting devices or machines are known, for example, as pin pushing devices on the market. They serve in particular the introduction of nails as bolts in concrete. Starting from the ignition of a combustible blowing agent, for example a powder or a gas, in a combustion chamber, a driving piston is accelerated. This drive piston acts on the bolt, which was previously inserted or inserted in a receiving space. The bolt is in particular driven without pre-drilling into the ground, wherein it is at least partially guided by a bolt guide.

The driving piston comprises on the one hand a piston head, which is acted upon by the combustion gases, and the piston rod, whose end facing away from the piston head acts on the bolt. Typically, the piston rod, which is guided in a piston rod guide, has a smaller diameter than the piston head, which is guided in a piston head guide. However, this is not absolutely necessary.

It is known that the performance of such a setting device can be controlled over the length of the combustion chamber. As such, the space in the piston head guide is referred to, enter the fuel gases at the beginning of the thrust movement. More precisely, it could be called an incinerator room. It is limited by the side facing away from the bolt of the piston head, hereinafter referred to as the back, and is thus dependent on the position of the driving piston in the piston head guide. After driving a bolt, the driving piston is returned within the piston guide, wherein the position of the driving piston can be adjusted before the next driving. In addition to systems in which the piston recirculation is carried out by residual gas pressure, by electromotive drive or by an elastic buffer, in particular systems are known in which the return is effected by a relative movement of the housing and a displaceable piston guide, the piston guide the piston head guide and the piston rod guide as includes permanently connected components. Between two Setzvorgägen the piston guide is pulled out of the housing or pressed by a spring, while the drive piston held by a housing-fixed stop. The driving piston thus shifts relative to the piston guide. When the piston guide and the housing are pushed together, the drive piston remains opposite the piston guide, so that it finally stands in the starting position for the next driving operation.

For example, from the document DE 21 66 664 A, it is known to predetermine the way the piston return by a variable limitation of the displacement of piston guide and housing and thus to regulate the combustion chamber. The document provides that the piston guide is pulled out once and pushed together again before the setting tool is ready again for setting a bolt. However, with such a setting tool is already determined with the moving out of the piston guide, with which power the next driving occurs. If the power is to be adjusted before re-setting, a further reciprocation is necessary. It may happen that the operator makes an adjustment on the control wheel, but this will only take effect on the next drive-in. This can be confusing to the operator and cause many erroneous drive-in operations.

From the document US 5,029,744 it is known that not the displacement of piston guide and housing is changed, but in the return of an axially adjustable, fixed housing stop acts on the piston head. Again, the piston guide is pulled out and pushed together again, the path of this movement always remains the same. When pushed together then affects the adjustable stop on a collar on the piston head. A similar system is known from the document DE 25 48 014 DE, in which case the reciprocating movement takes place against a compression spring and the adjustable stop acts on the bolt to be driven away from the back of the piston head. Both setting tools, however, have the Disadvantage of a rear acting on the piston head stop. This requires either, as in the document US 5,029,744, a complex geometry of stop and collar on the piston head or, as in the document DE 25 48 014 DE, moving parts in the combustion chamber, which can wear out quickly and pollute.

The object of the invention is therefore to provide a setting tool, in which the power regulation can be done just before the attachment to the ground, without additional movements are necessary, and at the same time has a simple, robust construction.

This object is achieved by a setting device with the features of claim 1. The invention proposes that the driving piston are guided in a piston head guide and a piston rod guide and that these two guides are displaceable to each other. The displaceability allows for the return of the drive piston in two stages by alternately holding in the piston rod guide and the piston head guide. When pushing apart the piston rod guide and piston head guide of the drive piston is first held in the piston head guide. Thereafter, the drive piston can be held in the piston rod guide, while the piston rod guide and the piston head guide are pushed back into one another. According to the invention, the length of the displacement path is also adjustable and the length of the combustion chamber can be determined. Due to the two-stage return operation of the drive piston, the determination of the path taken thereby can be carried out in the second stage, ie in particular only when applying the setting tool against the ground. This allows an adjustment of the power even before the placement of the setting device, without a complete back-and-forth.

At the same time, a very simple construction can be achieved. The alternating holding can be done in each case via movable stops, but these need not act in particular, as described in the prior art, backwards on the piston head. It can also be dispensed with one of the stops when the friction in one guide is greater than in the other guide. In particular, the piston head guide on a higher friction, which allows that acts on the piston head no stop and thus can be dispensed with a complicated structure in this area. A stop in the area of the piston rod guide can For example, act on the front, the bolt facing the end of the piston rod. Preferably, therefore, a movable stop is arranged in the piston rod guide.

A manual operation of this stop is unnecessary if this is spring-actuated, which is why this is preferred. The stop can be removed from the piston rod guide before firing and driving in the bolt via another mechanism. In a preferred embodiment, however, a much simpler structure results in that the stop is displaced by the driving piston itself during the driving process. Since the forces for returning the driving piston are significantly lower than the forces during the driving operation, the stopper can be designed so that it is suppressed during driving.

Preferably, a bolt to be driven in is used as the stop. This can be supplied manually or automatically and provide the necessary support for the return of the drive bolt, for example, by a concatenation or a correspondingly tight seat in the region of the piston rod guide. This has the great advantage that no additional component is needed for the stop.

In a preferred embodiment acts between the piston head guide and the piston rod guide a compression spring, wherein the compression spring can act directly on the piston head guide and the piston rod guide or indirectly via other components. The compression spring causes the setting tool can be pressed against the force of the compression spring to the ground. This movement can serve for one of the first or second stage of the described repatriation of the driving piston, on the other hand, a safety query can be carried out in such a way that the setting device can be triggered only in the scheduled, ie tensioned state. Such mechanisms are well known and therefore need not be described here. With the movement away from the ground, the pressure spring automatically causes the piston head guide and piston rod guide to move apart and thus the other stage of the return of the drive piston. Thus, the operator does not need to make any additional movement for the piston return by the pressure spring in addition to the pressing of the device for unlocking. The displaceability of the piston head guide to the piston rod guide is preferably adjustable via a stop device. Alternatively, a manual measuring and adjusting the displacement would be conceivable. In contrast, a stop device has the advantage of a simple and quick handling.

Preferably, the stop device is rotatably adjustable, which is usually perceived as particularly illustrative for the operator. It is also particularly advantageous for handling when the axis of rotation for the adjustment coincides with the longitudinal axis of the drive piston. In addition, this allows a symmetrical and thus visually appealing design of the setting device can be achieved.

In a preferred embodiment, the stop device sleeve-like manner comprises the piston guide. In particular, with a rotating adjustment, this results in a particularly clear handling similar to that of cordless screwdrivers and the like. Known. In addition, this large gripping surfaces are possible, so that the adjustment is easily possible even with gloves.

Preferably, the stop means comprises at least two components, wherein the first component is supported directly or indirectly on the piston rod guide, while the second component is supported directly or indirectly on the piston head guide. In this case, both components can each be designed in one piece with the piston rod guide or the piston head guide. Due to the support on the piston rod guide and on the piston head guide whose relative movement can be directly influenced. The relative movement in turn can be used in a simple manner as described above to accomplish a part of the return movement of the driving piston.

In order to make the operation of the stop device as simple as possible, preferably the second component on the piston head guide is rotatable relative to the piston head guide, as it is closer to the operator than the first component on the piston rod guide and thus results in ease of use.

The invention will be explained in more detail with reference to two embodiments shown in the drawings. Show it: Figure 1a - 1c, the setting device according to the invention in a schematic sectional view in three different device states;

Figure 2 shows the same setting device in a sectional view corresponding to the device state shown in Figure 1 b; and

Figure 3 shows a second inventive setting tool in a sectional view.

The setting devices 1, 1 'shown in the figures are shown for clarity in each case without ignition mechanism, cartridge and handle and without Abblaslöcher for combustion gases, since it does not matter and such components are well known. The setting devices 1, 1 'are powder-operated setting devices 1, 1', but it could also be gas-operated setting devices.

The setting device 1 shown as the first exemplary embodiment in FIGS. 1a-1c and 2 serves for introducing a nail-like bolt 2 into a base 3 (see FIGS. 1a and 1c). The bolt 2 is driven by a driving piston 4 of the setting device 1 in the ground 3. The driving piston 4 is a rotationally symmetrical, rod-like component with a piston rod 5 of small diameter, which extends over a large part of the length of the driving piston 4 and the bolt 2 faces. Facing away from the bolt 2, a piston head 6 of approximately twice the diameter adjoins the piston rod 5. The driving piston 4 is guided in a piston guide 7, which is formed on the one hand by a piston rod guide 8 and on the other hand by a piston head guide 9. The piston rod guide 8 and the piston head guide 9 are each substantially tubular and telescopically slidable. The piston head guide 9 has a taper 10 on its end facing away from the bolt 2. The taper 10 forms a narrow cylindrical channel 11 and this in the driving piston 4 away from the direction of a conically widened seat 12 for a cartridge. Between the rear side 13 of the piston head 6 and the taper 10, a displacement 14 for the driving piston 4 is formed. In the recirculated position of the drive piston 4 shown in FIG. 1c, the displacement 14 is minimal and forms a combustion space 15. In the combustion space 15, the powder particles burn up Gases that expand and thereby drive the driving piston 4 in the direction of the bolt 2, which will be described in more detail below.

Between the piston rod guide 8 and the piston head guide 9 acts a compression spring 16 (not shown in Figure 2), in particular a helical spring, so that the piston rod guide 8 and the piston head guide 9 in the position shown in Figure 1 b, in which no force acts from the outside, pulled apart. Against falling out of the piston rod guide 8 from the piston head guide 9 acts a pin 17 in the piston head guide 9, which engages radially in a longitudinal groove 18 in the piston rod guide 8 (only shown in Figure 2). This engagement also prevents twisting of piston rod guide 8 and piston head guide 9 to each other.

The pushing together of piston rod guide 8 and piston head guide 9 is limited by a stop device 19. It consists of a first component 20, which is supported on the piston rod guide 8, and a second component 21, which is supported on the piston head guide 9. In Figures 1a - 1c, the first component 20 is shown as a hook-shaped cantilever, while the second component 21 is shown as a longitudinally displaceable block. Due to the displaceability, a distance A between the two components 20, 21 is adjustable. The distance A is shown in Figures 1b and 2 as a double arrow, while it is not visible in Figures 1a and 1c, since the two components 20, 21 are pushed together to stop. The displaceability of the second component 21 is symbolized by a double arrow B, wherein it, as shown below, depends less on an actual longitudinal displacement, but on the adjustability ansich.

Figure 2 shows the structural design of the two components 20, 21 as respective sleeve-shaped components which are telescopically slidable and cup-like radially inwardly facing shoulders 22 which are supported on correspondingly facing projections 37 on the piston rod guide 8 and the piston head guide 9. The first component 20 is not rotatable relative to the piston rod guide 8 by a press fit. It has at its second component 21 facing circular edge 23 in an axial direction facing narrow extension 24. When pushing together Piston rod guide 8 and piston head guide 9 penetrates the first component 20 telescopically in the second component 21 until the extension 24 abuts a stop surface 36 in the interior of the second component in the region of the shoulder 22. The abutment surface 36 is stepped over the circumference, similar to a spiral staircase. By rotation of the second component 21 relative to the piston head guide 9, the distance A and consequently the displacement path V of the piston rod guide 8 to the piston head guide 9 can thus be varied. The axis of rotation D of the second component coincides with the longitudinal axis L of the driving piston 4. The second component has a large peripheral surface 25, which allows easy manual adjustment. The components 20, 21 may have markings for the correct setting of the angle of rotation corresponding to the desired distance A. The distance A corresponds to the power of the setting device 1.

The piston rod guide 8 has a stop 26 for supporting the driving piston 4 in its front third in the driving direction. The stop 26 is shown in the figures 1a - 1c as a separate conical component, the spring-actuated by an opening 27 (see Figure 1a) is pressed into the interior of the piston rod guide 8. As is clear from Figure 2, the invention proposes to actually perform this stop 26 not as a separate component of the setting tool, but to use the bolt 2 to be driven as a stop. The bolt 2 is surrounded by a plastic sleeve 28. Several bolts 2 with plastic sleeves 28 form a chain 29, wherein the plastic sleeves 28 are connected to each other via predetermined breaking points 30. The chain 29 is pressed in a known manner by means of a magazine (not shown) resiliently in the piston rod guide 8, which for this purpose has a longitudinal slot 31 as an opening 27. The chain 29 is simultaneously supported in the axial direction of the setting tool 1 by the magazine. Thus, the einzutreibende bolt 2 form a resilient stop 26.

In Figure 2, a resiliently inwardly pivoting stop pawl 32 is also shown in the central region of the piston head guide 9 for retaining the driving piston 4. Furthermore, a tubular housing 33 is shown, which comprises the piston head guide 9 in the region of the taper 10 and can be movable or rigid with respect to this.

The function according to the sequence of figures 1a-1c is explained below. Figure 1a shows the setting tool 1 immediately after the driving of a bolt 2 in the substrate 3. The piston rod guide 8 and the piston head guide 9 are pushed into each other, so that the components 20, 21 of the stop means 19 abut each other. The operator has pressed the setting tool 1 against the ground 3 against the compression spring 16. The driving piston 4 is in the front in the driving direction position and therefore displaces the stop 26 radially outward.

Now, if the contact pressure is reduced and the setting tool 1 deducted from the substrate 3, the piston rod guide 8 and the piston head guide 9 are pushed apart by the compression spring 16 until the position shown in Figure 1 b and Figure 2 is reached. The driving piston 4 is held in this movement in the piston head guide 9. This can be done either by correspondingly high friction, as shown in Figures 1a - 1 c realized by an O-ring 34 on the piston head 6, or by the stopper pawl 32 shown in Figure 2. Since the piston rod 5 relative to the piston rod guide 8 shifted to the rear has, the stop 26 (Figures 1a - 1 c) and the next pin 2 (Figure 2) resiliently into the interior of the piston rod guide 8 and thus pushed in front of the piston rod 5. In this state, the performance of the setting tool 1 can be changed by adjusting the stop means 19.

When restoring the setting tool 1 against a substrate 3, the piston rod guide 8 and the piston head guide 9 are pushed into each other again until the components 20, 21 of the stop means 19 as shown in Figure 1c abut each other. During this movement, the driving piston 4 is supported on the stop 26 or the next bolt 2 to be driven in, as a result of which the driving piston 4 moves relative to the piston head guide 9. By the predetermination of the displacement V creates a combustion chamber 15 of predefined length and thus the desired performance of the setting device 1. By igniting a cartridge of the driving piston 4 is driven in the direction of the substrate 3 until the pin 2 is fully driven, or until the driving piston 4th with the piston head 6 runs on a buffer 35 made of rubber (Figure 2), which is arranged on the piston head 6 facing the end face of the piston rod guide 8. Due to the extremely high pulse of the driving piston 4, the stop 26 is displaced. In FIGS. 1a-1c, this is done by a radial displacement during the stop 26 in FIG corresponding bolt 2 is displaced axially, wherein the nearest predetermined breaking point 30 of the chain 29 breaks.

The power regulation can be done immediately prior to attachment to the ground 3, without the additional movements by the operator are necessary. At the same time results in a simple, robust construction with few components.

FIG. 3 shows an alternative construction of a setting tool V as a second exemplary embodiment, the position corresponding to the illustration in FIG. In the following, only the differences from the first exemplary embodiment will be discussed in order to avoid repetition. This also applies to the unchanged movement sequence. The same components are provided with the same reference numbers.

A significant difference arises from the fact that the piston rod guide 8 'includes the piston head guide 9' and not vice versa. Where the piston head guide 9 'is guided in the piston rod guide 8', the piston rod guide 8 'has a corresponding diameter extension 38. The advantage of this arrangement is in a significantly shorter overall construction compared to the first embodiment, resulting in a handy setting tool 1 'results.

Another difference lies in the stop device 19 '. In contrast to the first embodiment, the first component 20 'is rotatable, with respect to the piston rod guide 8'. Piston rod guide 8 'and first component 20' are connected to each other via a thread 39, so that it comes by a rotation to a relative movement. The second component 21 'is formed only as a shoulder 40 on the outer diameter of the piston head guide 8' and thus integral therewith. The shoulder 40 forms a stop surface 36 ', which points in the direction of the first component 20'. The first component 20 'has a hook-shaped extension 24', which can be brought to bear against the abutment surface 36 '. The corresponding movement counteracts a compression spring 16 ', which on the one hand on the first component 20', and thus indirectly on the piston rod guide 8 ', and on the other hand on the housing 33', and thus indirectly on the piston head guide 9 ', supported. The housing 33 'is fixedly connected to the piston head guide 9', preferably via a releasable connection (not shown).

Claims

claims

1. Internal combustion setting device (1, 1 ') for driving bolts (2) in a substrate (3), with

a driving piston (4, 4 '),

a piston head guide (9, 9 '),

- A piston rod guide (8, 8 ') and

- A combustion chamber (15) with adjustable length, characterized in that the piston head guide (9, 9 ') and the piston rod guide (8, 8') are displaceable to each other and that via an adjustment of their displacement path V, the length of the combustion chamber (15) determinable is.

2. Combustion-operated setting tool according to claim 1, characterized in that in the piston rod guide (8, 8 '), a movable stop (26) is arranged.

3. Internal combustion setting device according to claim 2, characterized in that the stop (26) is spring-actuated.

4. Combustion-operated setting tool according to claim 2, characterized in that the stop (26) is displaced during the driving operation by the driving piston (4).

5. Internal combustion setting device according to one of claims 2 to 4, characterized in that the stop (26) is a einzutreibender bolt (2).

6. Combustion-operated setting tool according to one of the preceding claims, characterized in that between piston head guide (9, 9 ') and piston rod guide (8, 8') a compression spring (16 16 ') acts.

7. Combustion-operated setting tool according to one of the preceding claims, characterized in that the displaceability of the piston head guide (8, 8 ') to the piston rod guide (8, 8') via a stop means (19, 19 ') is limited adjustable.

8. Combustion-operated setting tool according to claim 7, characterized in that the stop device (19, 19 ') is rotatably adjustable.

9. Combustion-operated setting tool according to claim 8, characterized in that the axis of rotation D of the stop device (19, 19 ') substantially coincides with the longitudinal axis L of the drive piston (4).

10. Combustion-operated setting tool according to claim 8, characterized in that the stop device (19, 19 ') sleeve-like manner, the piston head guide (9, 9').

11. Combustion-operated setting tool according to claim 8, characterized in that the stop device (19, 19 ') has a first component (20, 20'), which is supported on the piston rod guide (8, 8 '), and a second component (21 , 21 '), which is supported on the piston head guide (9, 9').

12. Combustion-operated setting tool according to claim 1 1, characterized in that the second component (21) is rotatable relative to the piston head guide (9).

13. Combustion-operated setting tool according to claim 1 1, characterized in that the two components (20, 21) engage telescopically in one another.