The present invention relates to a tool for driving in fasteners, comprising
The invention also relates to a method for driving in fasteners with a tool of this type.
Tools or devices for driving in fasteners are known in the state of the art. Devices of this type usually use combustion gases or operate pneumatically in order to transfer energy to the fastener.
These pneumatically operated or gas-powered tools are very heavy and are unsuitable for working in terrain which is difficult to access, for example due to the compressor required. Handling of the tool is also made difficult by a compressed air hose. In the case of gas-powered tools, gas cartridges accumulate as waste and exhaust gases are emitted. The same is also true of tools which operate with the combustion gases of a fuel. In addition, the driving-in devices which operate with combustion gases need to be serviced at regular intervals in order to enable smooth operation.
Due to these disadvantages, in agriculture when working in terrain which is difficult to access it is still common to rely on hammers or similar tools. However, with activities which require the repeated driving in of fasteners, such as e.g. staples or nails, driving in by hand is exhausting and enormously time-consuming.
Electromechanical tools for driving in fasteners are also known in the state of the art. EP 2 397 269 B1 describes a device for driving a fastener element into a substrate, with a mechanical energy store which is loaded with the aid of electrical energy, wherein the electric motor is supplied with decreasing energy while energy is being stored in the mechanical energy store. Through supplying the electric motor with decreasing energy, on the one hand the loading procedure of the mechanical energy store is unnecessarily lengthened, and on the other hand, due to the utilization of the entire speed range of the motor, in that combination in which the maximum load torque through the mechanical energy store is higher than the maximum drive torque of the motor, the lifespan of the motor is negatively affected.
EP 1 935 572 A1 describes a hand-guided driving device for fastener elements with a mechanical energy store in the form of a spring and a clamping device with a spindle drive. The decentralized arrangement of the clamping device and of the locking device can result in wedging and other problems in the guiding of the shooting device.
The object of the present invention is therefore to create a convenient tool for driving in fasteners, in particular staples, which avoids the disadvantages of the state of the art.
This is achieved by a tool with the features of claim 1.
The tool according to the invention possesses a mechanical energy store for storing mechanical energy. This serves to make it possible for the use of pneumatic devices or those which use combustion gases of a fuel to be dispensed with. Furthermore, the tool possesses an ejecting device by which energy stored in the mechanical energy store is able to be transferred to the fastener. The movement of the ejecting device between an ejecting position and a clamping position is guided by a guide device. In addition, the tool possesses an electric motor which drives a spindle drive. This serves to convert the rotational movement of the electric motor into a linear movement of the ejecting device. The ejecting device has a driver element and a shooting device, wherein the driver element of the ejecting device is able to be connected to the spindle drive and is able to be releasably coupled to the shooting device. Furthermore, a control device is provided, which can control the direction of rotation of the electric motor. Through rotation of the spindle drive in a first direction of rotation, the ejecting device can be moved in the direction toward the clamping position, wherein the mechanical energy store is loaded by this movement of the ejecting device. Furthermore, a locking device for locking the shooting device in the clamping position is provided. Through actuation of the locking device, the locking is able to be released and the shooting device is able to be moved in the direction toward the ejecting position.
According to the invention it is provided that the driver element is able to be moved in the direction toward the ejecting position through rotation of the spindle drive in a second direction of rotation and the locking of the shooting device is able to be released through the movement of the driver element in the direction of the ejecting position. It is thereby possible that, by means of the driver element, both the mechanical energy store can be loaded and the locking can be released, as a result of which the tool can be designed with fewer individual parts and in particular the possibility of a symmetrical, coaxial construction results. The actuation for firing the shooting device by changing the direction of rotation of the spindle drive is able to be realized very simply and is less prone to faults due to the electric motor.
Further advantageous embodiments of the present invention are defined in the dependent claims.
It can be provided that the locking device has at least one rotatably mounted catch element, which is preferably spring-assisted, spring-loaded or resiliently mounted and serves for locking the shooting device in the clamping position. The catch element can, for example, be supported by a sprung disk or tensioned by an annular spring. A preferably symmetrical arrangement of several catch elements around the spindle drive has proved to be particularly advantageous. It can also be provided that the axis of rotation of the catch element is arranged perpendicular to the axis of rotation of the spindle drive. Furthermore, it can be provided that the axis of rotation of the catch element does not run through the axis of rotation of the spindle drive.
Through the possible formation of the locking device as a mechanical component which holds the shooting device in the clamping position without additional power supply and is also able to be released without the supply of electrical energy, accidental firing of the shooting device can be virtually ruled out even in the case of deficient power supply. In addition, the use of a purely mechanical ejecting device makes it possible to save energy. This is advantageous in particular when the tool is to be kept in the clamped state for a long time without being fired. If more than one catch element is used, a redundancy is created in case a catch element fails.
It can be provided that the at least one catch element has a curved inner contour and/or a detent, optionally with a chamfered region, on the side facing the mechanical energy store.
The locking device can be released by disengaging the catch element or elements from the shooting device. This can be effected by rotating the catch element about its axis of rotation. The locking device can be released more easily due to the chamfered region of the detent because the rotational movement of the catch elements is initiated more easily. Furthermore, the chamfered region of the detent can, among other things, provide for a low-wear operation of the catch elements and thus of the locking device.
According to an embodiment example it is provided that the shooting device is formed substantially cylindrical and has a first wall element facing the clamping position and a second wall element facing the ejecting position, wherein the first and/or the second wall elements are formed as stop surfaces for the driver element. In this case, a force is able to be applied to the stop surface by the driver element for releasing the locking. A symmetrical construction of the ejecting device can thereby be realized.
Due to the direction of movement of the driver element in the direction toward the ejecting position, the force acts on the stop surface and thus on the shooting device likewise in the direction toward the ejecting position. Due to the action of this force, the necessary holding force, which the locking device has to exert on the shooting device in order that it is held in the clamping position, becomes greater. As soon as the force exerted by the driver element on the stop surface exceeds a certain threshold value, the shooting device can no longer be held in the clamping position by the locking device and, due to the energy transferred from the mechanical store, the shooting device moves at high speed in the direction toward the ejecting position, where a fastener is then launched. Due to its movement in the direction toward the ejecting position, the driver element thus presses the shooting device out of the locking, whereupon it converts the energy transferred from the mechanical store into kinetic energy (apart from losses due to friction), which can then be used to drive a fastener into a substrate.
It can be provided that the shooting device has at least one support strut via which the first wall element and the second wall element are connected to one another. Preferably, several support struts connect the first and the second wall element to one another. These are preferably arranged symmetrically around the spindle drive.
It is also possible for the support strut(s) and one wall element to be formed as one part. Likewise, it is possible for both wall elements and the support strut(s) to be formed as one part.
In a preferred embodiment of the invention, at least one sensor is provided for detecting the position of the ejecting device. In this case, a very wide variety of sensors, known per se in the state of the art, can be used.
Through the precise detection of the position of the ejecting device it is possible to position the driver element according to the position of the ejecting device, even after the power supply has failed, in order to avoid material damage in the case of a possible release of the locking device.
It can be provided that the control device is formed in such a way that the direction of rotation of the spindle drive is changed when a first position of the ejecting device is reached and/or the electric motor is switched off when a second position of the ejecting device is reached. It is thereby possible for the direction of rotation of the spindle drive to be changed as soon as the clamping procedure is completed and the shooting device is locked. The driver element can thus be moved in the direction toward the ejecting position directly after the clamping procedure in order to be able to fire a shot with little or no time delay. The control device can also regulate the rotational speed of the electric motor, wherein the electric motor is preferably operated at a constant rotational speed during the loading of the energy store.
It can be provided that a stop element is provided for the mechanical energy store, wherein the mechanical energy store is mounted between the stop element and the shooting device. The mechanical energy store is preferably formed as a helical spring, which can be supported on the stop element.
In this case, it can be provided that the spindle drive is mounted, preferably centrally, in the stop element.
It can be provided that the spindle drive is arranged, preferably centered, in the mechanical energy store, preferably within the helical spring.
It can be provided that the spindle drive is arranged centered in the ejecting device, preferably centered in the driver element, and/or centered in the shooting device.
A symmetrical construction of the essential parts of the tool can be made possible by a central, i.e. centered, positioning of the spindle drive in the mechanical energy store and/or in the ejecting device. This has the advantage that it results in an even loading of the particularly stressed parts of the device and no radial moments arise. Through the arrangement of the spindle drive within the mechanical energy store, a space-saving construction of the tool can be made possible.
It can be provided that the driver element is able to be arranged at least partially in the mechanical energy store, preferably within the helical spring, during the movement in the direction toward the clamping position. Such an arrangement enables a space-saving construction since the empty space, in particular within the helical spring, can be utilized. In addition, such an arrangement would offer the advantage that a coaxial construction is possible, as a result of which radial moments on the spindle drive can be avoided.
It can be provided that the spindle drive has a spindle nut, and the driver element has a tension disk which is able to be connected to the spindle nut, wherein the tension disk is able to be arranged within the shooting device, preferably between the first and the second wall elements.
It can be provided that, on the outside of the ejecting device, preferably on the second wall element, a damping element is arranged for retarding the shooting device. In this case, the damping element can consist of a resilient material. However, it is also conceivable that the damping properties of the damping element are able to be set, e.g. by using an adjustable air damper, which, for settability, is preferably fastened stationary on the firing pin seat. As a result, the penetration depth of the fasteners could be set depending on the substrate. Such a setting possibility would enable an only partial driving in of the fasteners. As a result, the tool can also be used to fix with a fastener more sensitive articles or objects, which would be destroyed or at least damaged in the case of driving in with full force.
It can be provided that the shooting device has a firing pin with which a fastener located in a launch position is able to be driven into a substrate.
It can be provided that the guide device has several guide bars, preferably arranged outside the ejecting device, which extend from the stop element in the direction toward the ejecting position. Because the guide device possesses several, preferably four or more, guide bars the risk that the ejecting device will jam or wedge is kept low. Furthermore, the use of several guide bars offers the advantage that, in the case of a symmetrical arrangement of the guide bars, no tilting moment arises in the case of material failure of the shooting device, in particular in the firing pin, and thus consequential damage in the tool can be prevented.
The tool can have an electrical energy store for driving the electric motor. Through the use of an electrical store it is possible to operate the tool independently of a power supply. With appropriate sizing of the electrical store, it is possible to use the device for one or more working days without additional power supply. As a result, the tool is attractive for working in rough terrain.
The tool can have a magazine for storing fasteners.
The object of the invention is also achieved by a method with the features of claim 19. According to this it is provided that the ejecting device is moved by the spindle drive in the direction toward the clamping position for loading the mechanical energy store and the shooting device is held by the locking device when the clamping position is reached. According to the invention, the driver element is moved by the spindle drive in the direction toward the ejecting position to release the locking device.
For this purpose it can be provided that, through a movement of the driver element in the direction toward the ejecting position, a force is applied to the shooting device, in particular the first or the second wall element, and the locking device is thereby released.
It can be provided that the position of the ejecting device, in particular of the driver element, is detected and the electric motor is controlled in dependence on the position of the ejecting device, in particular of the driver element.
It can be provided that an actuation of the ejecting device for driving in a fastener is prevented when no fasteners are located in the magazine.
It can be provided that the magazine has a preferably spring-loaded closure mechanism, which is opened only when the tool is pressed against a substrate. This property represents an important safety feature of the tool, which prevents a shot from being fired inadvertently. This is true above all in cases where the tool is moved frequently over a long period of time while the shooting device is held in the clamping position and thus would in principle be ready to fire.
It can be provided that the ejecting device is able to be moved in the direction toward the clamping position only when sufficient electrical energy for a driving-in procedure is stored in the electrical store. As a result, a sudden resetting of the ejecting device through discharging the mechanical energy store, which would occur when the electric motor is no longer supplied with electrical energy during movement of the ejecting device in the direction toward the clamping position, can be prevented. The kinetic energy released in this case, in the reverse acceleration, could damage the spindle drive, which is not designed for such high speeds.
Further advantages and details of the invention are discussed, for various embodiment examples, with reference to the following figures. There are shown in:
After the shooting device 2 has reached the clamping position S, the direction of rotation of the spindle drive 8 is changed and the driver element 6 is moved back in the direction RA toward the ejecting position A. In this case, the movement of the electric motor 9 is controlled via the control device 11. Then, a shot is fired by pressing the push button 30. For this purpose, the driver element 6 is moved further in the direction toward the ejecting position A. As a result, the driver element 6 presses on the second wall element 15 of the shooting device 2, as a result of which a force F is applied to it. Through the movement of the driver element 6, the force F becomes greater and greater until finally the holding force of the locking device 7 is no longer sufficient to hold the shooting device 2 in the clamping position S. The locking is then released and the energy stored in the mechanical store 3 is transferred suddenly to the shooting device 2, which for its part transfers this energy to the fastener 10 (staple in this case). Through the transfer of force from the shooting device 2 via the firing pin 23 to the fastener 10, the latter is driven into the substrate. The ejecting movement of the shooting device 2 is cushioned by the damper 22.
Three sensors 17 are incorporated for detecting the position of the shooting device 2. These are formed as SMD fork light barriers and detect whether the shooting device 2 is located in the clamping position S or in the ejecting position A. As a result, the position of the ejecting device 5 can also be determined after a possible interruption of the power supply. In addition, a sensor 17 detects whether the driver element 6 is touching the second wall element 15. After a shot has been discharged, the shooting device 2 is brought back into the clamping position S—in the event that fasteners 10 are available in the magazine 26 and there is sufficient electrical energy in the electrical store 25. After catching in place, the driver element 6 is moved in the direction RA toward the ejecting position A. As soon as the driver element 6 is in contact with the second wall element 15, this is detected by a sensor 17 and the driving by the electric motor 9 is stopped. Only an actuation of the tool 1 at a switch provided for this purpose, for example the push button 30, brings about a further movement of the driver element 6 and an application of a force F to the second wall element 15.
Both the barrel 27 and the magazine 26 are formed such that the magazine 26 can be detached from the barrel 27. The firing of a shot can be blocked by means of the safety plate 41 if the barrel 27 is not pressed against a substrate. This represents an important safety feature in order to prevent a shot from being discharged unintentionally or prematurely.
Furthermore, the tool 1 is equipped with an electrical store 25 in the form of a storage battery.
Here, the two wall elements 14, 15 are connected via support struts 16. The spindle drive 8 is mounted via axial bearings 31 in the bearing seat 19 at the rear end of the guide device 4 in the stop element 18 of the mechanical store 3. In this case, the stop element 18 acts as bearing seat 19.
In
The ejecting device 5 in the uncocked state in the ejecting position A is depicted in
The symmetrical arrangement of the individual guide bars 24 of the guide device 4 can minimize the risk that the shooting device will wedge or jam. Through the symmetrical and coaxial construction of the ejecting device 5 together with the guide device 4 and the centrally arranged spindle drive 8, the occurrence of radial moments can also be prevented.
The fasteners 10 are pressed in the magazine 26 along the magazine guide 37 by the cylindrical compression springs 40 in the direction toward the safety plate 41 and thus in the direction toward the barrel 27. If there are no more fasteners 10 in the magazine, another shot is prevented from being discharged through activation of the SMD toggle switch 39 by the thrust piece 43.
The position of the magazine 26 on the barrel 27 is ensured by sprung ball pressure pieces 45. In order to refill new fasteners 10 into the magazine 26, the magazine rail with base 38 can be separated from the magazine guide 37. In order to secure the position of the magazine rail 38 in the magazine guide 37, sprung ball pressure pieces 45 are used.
The precise shape of the catch elements 12 is represented in
In this case, the geometry of the bevel 46, in particular the angle relative to the perpendicular to the upper boundary surface of the catch element 12, can be chosen such that the locking by the locking device 7 does not act in a self-energizing manner. As a result, a rotation of the catch element 12 about its axis of rotation 48 due to a force being exerted in the direction toward the spindle drive is made easier. In the installed state, this perpendicular can be oriented in the direction toward the center of the shooting device 2, thus, e.g. toward the spindle drive 8. The angle relative to the perpendicular can e.g. be in a range between 0 and 30°, preferably 10°.
The catch elements 12 can furthermore have a curved outer contour 49, which make possible an easier rotation of the catch elements 12 when acted on by the ring 34. In this case, a region of the ring 34 can be provided with a bevel 50, as a result of which an even easier rotation of the catch elements 12 is made possible. Alternatively, it would also be possible to round off the region of the ring 34 and instead provide a corresponding bevel on that region of the catch elements 12 which is in contact with this region of the ring 34.
It is not absolutely necessary to form individual or all of the elements 14, 15, 18, 33, 34 and/or 47 substantially circular. A symmetrical construction of one or more of these elements can also be achieved by a polygonal outer contour, e.g. a hexagonal or an octagonal outer contour.
1 tool
2 shooting device
3 mechanical store
4 guide device
5 ejecting device
6 driver element
7 locking device
8 spindle drive
9 electric motor
10 fastener
11 control device
12 catch element
13 inner contour
14 first wall element
15 second wall element
16 support strut
17 sensor
18 stop element
19 bearing seat for spindle drive
20 spindle nut
21 tension disk
22 damper
23 firing pin
24 guide bars
25 electrical store
26 magazine
27 barrel
28 casing
29 planetary gear
30 push button
31 axial bearing
32 position stop
33 firing pin seat
34 ring
35 detent
36 chamfered region
37 magazine guide
38 magazine rail with base
39 toggle switch
40 cylindrical compression springs
41 safety plate
42 cylindrical tension springs
43 thrust piece
44 short-stroke button
45 sprung ball pressure pieces
46 bevel
47 bearing element for catch element
48 axis of rotation for catch element
49 curved outer contour
50 bevel
51 curved contour
F force
S clamping position
A ejecting position
RS direction toward the clamping position
RA direction toward the ejecting position
Number | Date | Country | Kind |
---|---|---|---|
A 51105/2019 | Dec 2019 | AT | national |
Number | Date | Country | |
---|---|---|---|
Parent | PCT/AT2020/060469 | Dec 2020 | US |
Child | 17842045 | US |