SETTING TOOL AND METHOD FOR OPERATING A SETTING TOOL

Abstract

The invention relates to a setting tool for fastening elements, comprising a driving piston that can be driven by a primary drive, and comprising a secondary drive. In order to create a lightweight, handy setting tool, the primary drive is combined with the secondary drive in a hybrid drive system for the driving piston in such a way that the driving piston can be driven by both the primary drive and the secondary drive.

Claims

1. A setting tool for fastening elements, comprising a driving piston which can be driven by a primary drive, and comprising a secondary drive, wherein the primary drive is combined with the secondary drive in a hybrid drive system for the driving piston in such a way that the driving piston can be driven by both the primary drive and also the secondary drive.

2. The setting tool according to claim 1, wherein the primary drive is a gas-powered drive.

3. The setting tool according to claim 1, the secondary drive is an electric motor-powered drive.

4. The setting tool according to claim 3, wherein the secondary drive is drivingly connected to a piston rod of the driving piston.

5. The setting tool according to claim 1, wherein the primary drive and the secondary drive are connected to a common control unit.

6. The setting tool according to claim 1, wherein a clutch which allows uncoupling of the secondary drive from the driving piston is associated with the secondary drive.

7. A method for operating the setting tool according to claim 1, the method comprising accelerating the driving piston solely by the primary drive in a first mode of operation, and accelerating the driving piston by the primary drive and the secondary drive in a second mode of operation.

8. The method according to claim 7, further comprising accelerating the driving piston solely by the secondary drive in a third mode of operation.

9. The method according to claim 7, wherein the primary drive has a combustion zone and the secondary drive supercharges the combustion zone with aid from the driving piston.

10. The method according to claim 7, wherein the primary drive and the secondary drive are both controlled by a common controller.

11. A computer program product with a program code for carrying out the method according to claim 7.

12. The setting tool according to claim 2, wherein the secondary drive is an electric motor-powered drive.

13. The setting tool according to claim 12, wherein the secondary drive is drivingly connected to a piston rod of the driving piston.

14. The setting tool according to claim 2, wherein the primary drive and the secondary drive are connected to a common control unit.

15. The setting tool according to claim 3, wherein the primary drive and the secondary drive are connected to a common control unit.

16. The setting tool according to claim 4, wherein the primary drive and the secondary drive are connected to a common control unit.

17. The setting tool according to claim 2, wherein a clutch which allows uncoupling of the secondary drive from the driving piston is associated with the secondary drive.

18. The setting tool according to claim 3, wherein a clutch which allows uncoupling of the secondary drive from the driving piston is associated with the secondary drive.

19. The setting tool according to claim 4, wherein a clutch which allows uncoupling of the secondary drive from the driving piston is associated with the secondary drive.

20. The setting tool according to claim 5, wherein a clutch which allows uncoupling of the secondary drive from the driving piston is associated with the secondary drive.

Description

[0016] Further advantages, features and details of the invention are apparent from the following description in which various embodiments of the invention are described in detail with reference to the drawings.

[0017] The sole accompanying drawing shows a simplified representation of a setting device according to the invention.

EXEMPLARY EMBODIMENTS

[0018] In the accompanying drawing a setting tool 1 with a housing 2 is shown in highly simplified form. The housing 2 comprises a handle (not shown), on which the setting tool 1 can be mounted for driving in a fastening element 6 which extends out of the setting tool 1 at a setting end 5 and can be driven into a substrate (likewise not shown).

[0019] The fastening elements 6 which are used are preferably provided by means of a magazine (not shown) which is located inside the device and is mounted in the vicinity of the setting end 5 on the setting tool 1. The fastening elements 6 are automatically withdrawn, preferably individually, from the magazine and are provided in an element guide 4 at the setting end 5.

[0020] Energy required for driving the fastening elements 6 into the substrate is transmitted to the fastening element 6 in the piston guide 3 by means of a driving piston 7 which is guided in the piston guide 3.

[0021] Energy required for driving the fastening elements 6 into the substrate is provided, for example, in a fuel tank 8 in the interior of the setting tool 1. The fuel in the fuel tank 8 is preferably an expandable gas, such as liquid gas. Therefore the fuel tank 8 is also designated as a gas canister or gas cartridge.

[0022] The fuel tank 8 can be connected by means of an adjustable or regulable metering device 10 and a connecting line 11 to a combustion chamber or a combustion zone 12. The metering device 10 is preferably configured as a metering valve.

[0023] In the combustion zone or the combustion chamber 12, fuel, i.e. gas, from the fuel tank 8 is mixed with air to produce a combustible mixture which is ignited by an ignition device 14 in order to drive a fastening element 6, such as a bolt or a nail, out of the element guide 4 at the setting end 5 into the substrate. When a trigger of the setting tool 1 is actuated, the energy required for driving in is transmitted by means of the driving piston 7 from the combustion chamber 12 to the fastening element 6 at the setting end 5.

[0024] For control purposes a controller or control unit 20 is arranged in the setting tool 1. A control line 16, which is also designated as an ignition cable, extends from the controller 20 to the ignition device 14 in the combustion zone 12. By means of the ignition cable 16 the ignitable mixture in the combustion zone 12 is ignited with the aid of the ignition device 14. By means of a control line 17 the metering device 10 is connected in control terms to the controller 20.

[0025] The combustion chamber 12, the ignition device 14 and the metering device 10 with the fuel tank 8 constitute a primary drive 21 for the driving piston 7. The primary drive 21 is combined with a secondary drive 22 in a hybrid drive system for the driving piston 7.

[0026] The secondary drive 22 is configured as an electric motor-powered drive with an electrical power supply device 23 and an electric motor 24. The electrical power supply device 23 is configured for example as a battery or accumulator and is connected by means of a power supply line to the electric motor 24.

[0027] Furthermore, the electric motor 24 is connected in control terms to the controller 20 by means of a control line 18. Thus the controller 20 constitutes a common controller for the primary drive 21 and the secondary drive 22.

[0028] The electric motor-powered drive which constitutes the secondary drive 22 is drivingly connected by means of a coupling device 25 to a piston rod 30 of the driving piston 7. The coupling device 25 comprises a gear 26 connected for conjoint rotation to a drive shaft of the electric motor 24.

[0029] The gear 26 has an external toothing 27, which is in engagement with a linear toothing 28 and is formed on the piston rod 30 of the driving piston 7. The coupling device 25 can be combined with a clutch (not shown) which allows engagement and disengagement of the electric motor 24.

[0030] A display of the setting tool 1 is indicated by a rectangle 34 connected to the controller 20. An input device of the setting tool 1 is indicated by a rectangle 35 likewise connected to the controller 20. Operation-dependent information about the setting tool 1 is visibly presented externally for an operator by means of the display 34. By means of the input device 35 the operator can make inputs on the setting tool 1.

[0031] In the accompanying drawing a first position or starting position of the driving piston 7 is indicated by a line 38. The driving piston 7 is retained in its first position or starting position by a magnet device 40. The magnet device 40 comprises, for example, two magnets of which the north and south poles are indicated by rectangles. Alternatively or in addition the driving piston 7 can be retained in its starting position or first position 38 by friction.

[0032] The driving piston 7 can be moved out of its first position or starting position 38 into its second position illustrated in the drawing by the primary drive 21 and/or the secondary drive 22. Due to the acceleration of the driving piston 7 associated therewith, the fastening element 6 can be driven into the substrate at the end 5 of the setting tool 1.

[0033] After the setting operation the driving piston 7 can be brought back again into its starting position or first position 38 by the thermal piston which is conventional in gas devices or by the secondary drive 22 with the electric motor 24 and the coupling device 25.

[0034] The electric motor-powered drive 22 which constitutes the secondary drive can be provided, as illustrated, by means of the motor unit 24 which engages mechanically on the piston rod 30. Alternatively or in addition the electrical drive can take place by means of a coil system (not shown) on the piston guide side and a corresponding counterpart on the piston side, for example in the form of a solenoid plunger. This type of electrical drive is similar to a reciprocating piston magnet.

[0035] The setting tool according to the invention can be operated in five different modes of operation. In a first mode of operation, which is also designated as standard combustion, the driving piston 7 is accelerated exclusively by means of the combustion pressure provided by the primary drive 21.

[0036] Before the combustion the driving piston 7 is located in its starting position or first position 38, which is also designated as the rearmost position. Due to the ignition of the combustible mixture in the combustion chamber 12 with the aid of the ignition device 14, the driving piston 7 is suddenly moved into the second position illustrated in the drawing, wherein the driving piston 7 is accelerated.

[0037] In a first mode of operation, which is also designated as hybrid drive, the driving piston is accelerated both by the combustion pressure provided by the primary drive 21 and also by the electric drive which constitutes the secondary drive 22. In this case the combustion process is started in the hybrid drive system just as in the first mode of operation. Due to the common control 20 for the two drives 21 and 22, during the piston acceleration the electric motor 24, which is associated with the secondary drive 22, is switched on.

[0038] In a third mode of operation the secondary or electric motor-powered drive 22, which is also designated as an electrical drive, is used for pre-compression of the combustible mixture in the combustion zone 12. The piston acceleration takes place due to the combustion pressure increased as a consequence of the supercharging. The third mode of operation is also designated as combustion with supercharging.

[0039] The driving piston 7 is located initially in its second position illustrated in the drawing in front of the rear position 38. In order to reach a higher oxygen concentration in the combustion chamber 12, the electric motor-powered drive 22 moves the driving piston 7 towards the rear, i.e. towards the combustion chamber 12. In this way the air in the combustion chamber 12 is compressed.

[0040] Simultaneously, the gas from the fuel tank 8 is injected by means of the metering device 10 into the combustion chamber 12. Then the ignition takes place by the ignition device 14. The subsequent combustion with the pressure buildup accelerates the piston and moves the piston 7 out of its starting position 38 again into its second position illustrated in the drawing.

[0041] In the third mode of operation the electric motor-powered drive 22 is preferably coupled to the driving piston 7 only during the supercharging phase. Subsequently the driving piston 7 is controlled mechanically or electrically and brought out of engagement with the driving piston 7. As a result, an undesirable incorrect loading during the working stroke of the driving piston 7 is prevented in a simple manner.

[0042] In addition, in a fourth mode of operation the driving piston 7 is also accelerated in the working direction by the electrical drive 22. The pre-compression of the air in the combustion zone 12 takes place as in the third mode of operation. However, during the acceleration of the driving piston 7 the electric motor-powered drive 22 is additionally switched on for accelerating the driving piston 7. The fourth mode of operation is also designated as a hybrid drive with supercharging.

[0043] In a fifth mode of operation the driving piston 7 is accelerated exclusively by the electric motor-powered drive 22. The fifth mode of operation is also designated as an electric drive. The fifth mode of operation with the electric drive is suitable, in particular, for applications in which only a relatively low setting energy is required in order to drive the fastening element 6 into the substrate. At the start of the electric drive the driving piston 7 is located in its first position or starting position 38.

[0044] The setting tool 1 according to the invention with the hybrid drive system can be lighter than a conventional gas device and also lighter than a battery-operated setting tool. With the setting tool 1 according to the invention, higher setting energies can be achieved by the hybrid drive system than with conventional setting tools.

[0045] The different possibilities for combining the individual drives 21 and 22 make possible a very great variation of the setting energy. With reduced setting energy, gas or accumulator capacity can be saved by comparison with standard energy settings, such as for example a piston advance adjustment.