EP1671750B1 - Machine for fastening or drilling and method for controlling the sense of rotation of such a machine - Google Patents

Description

The invention relates to a machine for screwing or drilling, with a motor for driving a drive shaft, with an electronic control for controlling the machine, with a motor switch for switching on and off the motor, and with switching means for switching between right / left rotation and vice versa ,

The invention further relates to a method for controlling the direction of rotation of a machine for screwing or drilling.

Such drills or screwdrivers have been in use for a long time. The document US 5,105,130 shows such a machine according to the preamble of claim 1.

The switching between clockwise and anticlockwise rotation is usually done by pressing a mechanical switching element.

During operation, screwdrivers are normally used continuously in clockwise or permanently counterclockwise operation. In the clockwise direction screwed connections are tightened, while in the counterclockwise direction screwed connections can be loosened.

The mechanical change, however, proves to be disadvantageous if the screwdriver is to be operated only for a short time in an opposite direction, which is opposite to the direction of clockwise or counterclockwise rotation set in principle. For this purpose, in turn, the switch for the clockwise / anti-clockwise rotation must be changed.

The invention is therefore an object of the invention to provide an improved machine for screwing or drilling, which ensures a simplified operation, in particular an improved right / left rotation changeover. Furthermore, a method for controlling the direction of rotation of a machine for screwing or drilling is to be specified, which avoids the disadvantages described above.

This object is achieved by a machine for screwing or drilling, with a motor for driving a drive shaft, with an electronic control system for controlling the machine, with a motor switch for on and Turning off the engine, with switching means for switching between right / left rotation and vice versa, and with a timer, the switching between right / left rotation and vice versa only within a certain period of time between operation of the switching means for the right / left rotation and actuation of the engine switch allowed to switch on the machine.

Switching between clockwise and anti-clockwise rotation can be done in a simple manner by the switching means is actuated to switch within the predetermined time window, which can be done for example by means of a button. An incorrect operation can be largely avoided.

According to one embodiment of the invention, switching means for switching between continuous-action / continuous-reverse operation and vice versa, as well as storage means for storing the Dauerlinkslauf- or Dauerrechtlaufzustands are provided.

This makes it possible to electronically change and store a continuous right-hand rotation or continuous reverse rotation so that the machine always runs in the same direction even when the motor is operated several times.

The machine can be operated once in the opposite direction from a once set continuous rotation or continuous reverse when using a changeover switch for the clockwise / anticlockwise rotation in the specified period of time.

Such control of the clockwise or anti-clockwise rotation offers considerable advantages for the user. Namely, the user can as desired, set a continuous right-hand rotation or long-term reverse run that is retained even after the machine has come to a standstill. Also, the user can switch this continuous right or Dauerlinkslauf by pressing a switch for the right / left rotation once in a different direction. For example, the machine can be operated continuously in the clockwise direction for tightening screwed connections and, after operation of a changeover switch within a predetermined time window, in each case for a single screwing operation in the counterclockwise rotation. The next time the engine is started, the machine is again operated in clockwise direction, unless the right / left switch is pressed again.

Conversely, the machine can be put into a permanent left-hand rotation state, for example, for loosening of screw connections, from which a reverse direction of rotation can be adjusted once upon actuation of the switch for the right / left rotation within the predetermined time window.

According to a further embodiment of the invention, the electronic control is designed such that when decoupling the machine from the power supply, the machine is reset to continuous action.

This measure has the advantage that the machine is always basically operated in clockwise rotation when commissioning for the first time, which corresponds to the commonly used direction of rotation. Only by a deliberate conversion is a conversion to a one-time counterclockwise rotation or a long-term reverse rotation.

This is also particularly advantageous when the machine is used by different users or operated at changing locations.

If the machine is equipped with a rechargeable battery, then the reversion to a continuous right-hand run can be connected to the decoupling of the machine from the rechargeable battery.

According to a further embodiment of the invention, the switching means comprise first switching means by means of which a stored continuous right or Dauerlinkslauf for a single start of the machine in the respective reverse direction of rotation can be implemented.

In this way, a particularly advantageous use of the machine for different types of use results.

According to a further embodiment of the invention, the time period for switching between right / left rotation and vice versa and operation of the engine switch is at most 30 seconds, preferably at most 15 seconds, more preferably about 5 seconds.

In this way, the user is given on the one hand sufficient time to allow a change between right / left rotation and vice versa. On the other hand, the time window for switching is not unnecessarily increased.

According to a further embodiment of the invention, the machine has indicator means for indicating the counterclockwise rotation.

In this way, the user can be optically and / or acoustically signaled that the machine is operated in the left-hand rotation or clockwise.

According to a further embodiment of the invention, the switching means comprise a first switch and a second switch which, when actuated in a fixed sequence, allow switching between permanent right / left running and vice versa.

Here, for example, the first switch can be configured as a light switch, which additionally allows the activation of a lighting, while the second switch can be configured as a right / left switch.

In this way, a deliberate switch between continuous right and long-term running and vice versa in a simple way possible.

At the same time, one of the two switches is provided with a double function, in order to also enable an actuation of the lighting, without the need for another switch is necessary.

According to a further embodiment of the invention, the light switch is coupled to the motor switch such that in a first switching stage, only the light switch is actuated, while in a second switching stage, the light switch and the motor switch are actuated simultaneously.

This has the advantage that the light switch can be used separately first to illuminate the workplace before the motor switch is actuated, so before the machine starts. This ensures that the machine can be correctly set up at the workplace.

According to a further embodiment of the invention, at least one of the switches is designed as a button. Preferably, even all of the switches are designed as buttons.

Hereby, a particularly simple structure can be ensured, since the key signals of the switches can be evaluated electronically, so that a mechanical switching, which must be reset, eliminated.

According to a further embodiment of the invention, the motor switch is designed as a gun switch. In an additional development of the light switch and the motor switch can be actuated by means of a common pusher.

In this way, a particularly simple and ergonomic design results in connection with the design of the machine in pistol form.

It goes without saying that the machine can also have any other design. For example, it could be a rod angle screwdriver. Again, preferably the light switch and the motor switch can be actuated by means of a common pusher, which is not designed as a gun switch.

1. (A) Einstellen der Drehrichtung auf Rechtslauf oder auf Linkslauf;
2. (B) Überwachen, ob ein Schaltmittel zur Umschaltung der Drehrichtung betätigt wird;
3. (C) Starten eines Timers, falls eine Aktivierung des Schaltmittels erfasst wird;
4. (D) Überwachen, ob innerhalb einer vorgegebenen Zeitspanne nach Starten des Timers ein Motorschalter betätigt wird, um den Motor zu starten;
5. (E) falls der Motorschalter innerhalb der vorgegebenen Zeitspanne betätigt wird, Umkehren der Drehrichtung von Schritt (A) und Starten des Motors mit der umgekehrten Drehrichtung und
6. (F) Starten des Motors mit der im Schritt (A) eingestellten Drehrichtung, falls der Motorschalter nach Ablauf der vorgegebenen Zeitspanne betätigt wird.

With regard to the method, the object of the invention is achieved by a method for controlling the direction of rotation of a machine for screwing or drilling with the following steps:

1. (A) Setting the direction of rotation to clockwise or counterclockwise;
2. (B) monitoring whether a switching means for switching the direction of rotation is actuated;
3. (C) starting a timer if activation of the switching means is detected;
4. (D) monitoring whether a motor switch is operated within a predetermined period of time after starting the timer to start the engine;
5. (E) if the engine switch is operated within the predetermined time period, reversing the direction of rotation of step (A) and starting the engine in the reverse direction of rotation and
6. (F) Starting the engine with the direction of rotation set in step (A) if the engine switch is operated after the predetermined time has elapsed.

Switching between clockwise and anti-clockwise rotation can be done in a simple manner by the switching means is actuated to switch within the predetermined time window, which can be done for example by means of a button. An incorrect operation can be largely avoided.

According to a further embodiment of the invention, a continuous direction of rotation is stored.

The predetermined period of time for switching the direction of rotation is preferably at most 30 seconds, more preferably 15 seconds, particularly preferably at most 5 seconds.

In a preferred embodiment of this embodiment, the continuous direction of rotation when first starting the machine or when disconnecting the machine from a power supply to a preset state, preferably set to continuous rotation.

According to a further embodiment of the invention, the continuous direction of rotation when activating a particular switching means is reversed and stored.

• (G) Betreiben der Maschine mit der gespeicherten Dauerdrehrichtung, falls der Motorschalter betätigt wird, ohne dass das Schaltmittel zur Umschaltung der Drehrichtung aktiviert wird oder wenn der Motorschalter erst betätigt wird, nachdem die vorgegebene Zeitspanne des Timers abgelaufen ist und
• (H) einmaliges Betreiben der Maschine mit der umgekehrten Drehrichtung wie die gespeicherte Dauerdrehrichtung, falls der Motorschalter gemäß Schritt (E) bei zuvor aktiviertem Schaltmittel zur Umstellung der Drehrichtung betätigt wird, bevor die vorbestimmte Zeitspanne des Timers abgelaufen ist.

According to a further embodiment of the invention, the method has the following additional steps:

• (G) operating the machine with the stored continuous direction of rotation, if the motor switch is operated, without the switching means is activated to switch the direction of rotation or if the motor switch is only operated after the specified time period of the timer has expired and
• (H) operating the machine in the reverse direction once like the stored continuous rotation direction, if the motor switch according to step (E) is actuated with previously activated switching means for switching the direction of rotation before the predetermined time period of the timer has expired.

According to a further embodiment of the invention, the predetermined period of time is at most 30 seconds, more preferably 15 seconds, particularly preferably 5 seconds.

According to a further embodiment of the invention, a left-hand operation by means of indicator means for a user of the machine is displayed, for which example, flashing LED's can be used.

This will prevent the machine from being mistakenly operated in the wrong direction.

Figur 1

eine perspektivische Ansicht einer erfindungsgemäßen Maschine in vereinfachter Darstellung;

Figur 2

ein Flussdiagramm zur Darstellung der Schaltlogik der elektronischen Steuerung, mittels derer eine Umschaltung zwischen Rechtslauf bzw. Linkslauf bzw. umgekehrt ermöglicht wird; und

Figur 3

eine Wahrheitstabelle, aus der sich die Zuordnung der verschiedenen Schaltzustände gemäß Figur 2 ergibt.

Further features and advantages of the invention will become apparent from the following description of a preferred embodiment with reference to the drawings. Show it:

FIG. 1

a perspective view of a machine according to the invention in a simplified representation;

FIG. 2

a flowchart illustrating the switching logic of the electronic control, by means of which a switch between clockwise or counterclockwise or vice versa is enabled; and

FIG. 3

a truth table, from which the assignment of the different switching states according to FIG. 2 results.

In FIG. 1 is a machine according to the invention, which is designed as a screwdriver, shown and designated overall by the numeral 10.

The machine 10 has a pistol-shaped housing 11, in which an indicated only with the numeral 12 engine, a transmission and an electronic control 26 are received. From the engine 12, a drive shaft 14 for driving a tool, such as a screwdriver bit, driven by the gear, not shown. At the front end of the housing 11, which faces the drive shaft 14, there are a series of lighting elements 29, such as LEDs, which emit forwardly and provide illumination of the work site (in FIG FIG. 1 only one LED is visible). The housing 11 has at its lower end a pistol grip 16, at the lower end of a power cable 22 is provided, which can be connected via a power plug 24 to a voltage source. In the area of the "gun trigger" a pusher 18 is provided, via which the engine 12 and the lighting elements 29 of the machine can be actuated. The pusher 18 acts in this case in a first switching stage on a light button, the in FIG. 1 is indicated as SWLICHT. If the pusher 18 further depressed, it also acts in a second switching stage on a motor switch, which is also designed as a button and in FIG. 1 with SWSTART is indicated. At the top of the housing 11 is also a switch 20, which is designed as a button and to switch between right / left rotation and vice versa.

Further, located in the front upper portion of the housing, an indicator means 28, which serves to indicate a left-hand operation, which may be one or more LEDs, which are operated, for example, flashing.

It is understood that the arrangement of the switching elements and the lighting elements in the in FIG. 1 shown embodiment is merely exemplary in nature and that depending on the design and housing of the machine in question, other arrangements may be preferred.

Likewise, it is understood that the machine 10 may also be designed as a battery-powered machine, so that the power cord 22 and the power plug 24 omitted and instead, for example, at the bottom of the pistol grip 16, a removable battery pack can be provided.

In the machine 10, the electronic control 26 is implemented as a microprocessor-based control that controls all functions of the machine, such as soft start of the engine, engine braking at shutdown, overload protection, possibly speed control and / or power control and other test or control functions.

However, the aforementioned functions are not the subject of the present invention. The present invention relates to a novel adjustment for the operation of the machine in clockwise or counterclockwise rotation. These different modes and their settings are explained below with reference to a flowchart that is described in FIG. 2 is shown and indicated generally by the numeral 30. Furthermore, for this purpose, a function table or truth table to be considered, which in FIG. 3 is shown.

The machine 10 can be operated by reversing the motor 12 basically clockwise or counterclockwise. The controller 26 is now designed so that in the ground state, that is to say when the machine 10 is first put into operation, a so-called continuous rotation is established. This continuous right can be changed by pressing a specific key combination in a long-term run. Furthermore, the machine can be operated by pressing the right / left button 20 once in the reverse direction of rotation, if the motor switch is operated within a predetermined time window.

In FIG. 2 the setting of a continuous or sustained run is indicated by the value of the variable DLL. If DLL = 1, then the persistent reverse is set, that is, the mode Flag is set. If DLL = 0, continuous rotation is set. The direction of rotation of the drive shaft is indicated by the variable DIR. DIR = 0 means that the drive shaft rotates clockwise while DIR = 1 means a counterclockwise rotation.

The controller 26 further includes a left-turn timer, which is activated by pressing the button 20. The value of the timer is indicated by the variable TLL. If TLL = 0, then the timer is off or the maximum time of the timer, for example 5 seconds may have expired. If TLL = 1, the timer has not yet expired.

In FIG. 2 Furthermore, the light switch is used, which is abbreviated by SWLICHT. SWLICHT is actuated by depressing the pusher 18 in a first switching stage. If the pusher 18 further depressed, so in addition to SWLICHT the motor switch is actuated in FIG. 1 designated by SWSTART.

In FIG. 2 For example, decision branches are indicated by diamonds in the usual way, the outputs being denoted by Y and N, which stands for "yes" or "no".

Further used FIG. 2 in the usual way rectangular function blocks as well as a start point and an end point, which designate the logical beginning of the decision logic or the logical end of the decision logic.

Those with the decision logic according to FIG. 2 achievable combinations are in the truth table (function table) according to FIG. 3 summarized.

The first line means that, when the motor switch SWSTART is pressed, there is no permanent left rotation, the timer has not been actuated or has expired, the machine is running in the clockwise direction: DIR = 0.

It can be seen from the second line that, when the motor switch SWSTART is actuated, there is no permanent left rotation and the push button SWRL is used to switch right / left was (SWRL = 1) and the timer has not yet expired (TLL = 1) the machine is operated in reverse: DIR = 1.

The third line of FIG. 3 it can be taken out that, when the motor switch SWSTART is actuated, permanent reverse operation is set and the timer has not been actuated or has expired, the machine is also operated in anticlockwise mode: DIR = 1.

On the other hand, it can be seen from the last line that when the motor switch is actuated, long-term reverse operation is set and the timer has been activated and has not yet expired, the machine is operated in the clockwise direction: DIR = 0.

The machine can therefore be moved from the basic states DLL = 0 (continuous rotation) or DLL = 1 (continuous clockwise rotation) by depressing the motor switch in the set continuous running state. Alternatively, the right-to-left switch SWRL can be activated before the SWSTART motor switch is actuated. If the motor switch is then actuated within the specified timer time of 5 seconds, the set continuous direction of rotation is changed once in the reverse direction of rotation.

This behavior will now be explained in detail by means of FIG. 2 explained in more detail. After activating the decision logic by the start (start) according to paragraph 32 is first queried in the branch 34, whether the light switch SWLICHT was actuated via the trigger 18. If this is the case, then the right output results from the branch 34. In the branch 38 is now queried whether in addition to the light switch and the switch for clockwise / anticlockwise rotation SWRL has been actuated. If this is the case, a previously set persistent clockwise or continuous clockwise rotation is converted to the reverse direction of rotation and saved. This is considered and stored by the microprocessor using a "mode flag". In box 42 this is indicated by DLL =! DLL. It says the "!" for the negation, that is the logical NOT or NOT. If the conversion of the continuous direction of rotation in the box 42 has taken place, it is queried in the branch 44 as to whether the reversing switch SWRL has been released again. If this is the case, then it continues with the next query 46, if the motor switch has been pressed. If SWRL has not yet been released, it will wait until it has occurred, as indicated by the feedback loop.

If it is determined in the branch 34 that the light switch has not been actuated, it is first queried in the branch 36 as to whether the forward / reverse switch SWRL has additionally been actuated. If this is not the case, then the right-hand exit leads directly to the next branch 46, ie the query as to whether the motor switch has been actuated. If, on the other hand, the right-to-left switch SWRL is actuated, the timer is started in block 40 and the output leads to the next branch 46.

In the branch 46 is now queried whether the motor switch SWSTART is pressed. If SWSTART is not activated, the left output of the branch leads directly to end point 56 (STOP). If, in contrast, the motor switch is actuated, then the output of the branch 46 leads to the next branch 48. If continuous reverse rotation is now set, the timer has been activated and is not yet expired (DLL AND TLL), the result is the left output. Namely, it is the set Dauerlinkslauf switched to a clockwise rotation, which is displayed in block 50 with clockwise (DIR = 0). Thereafter, the timer is reset at block 54 (TLL = 0) and the process ends at 56.

If, on the other hand, it is determined in the branch 48 that the logical combination of the continuous left running DLL and the activated and not yet expired timer TLL is not true, then the right output results, so that the machine is operated in reverse, as in box 52 by DIR = 1 is shown. Subsequently, the timer in box 54 is stopped again and the process is completed at 56.

In branch 48, as an alternative to the query (DLL AND TLL), the logical expression (! DLL AND! TLL) is also interrogated via a logical OR. It is therefore queried whether continuous right is set and the timer has not been pressed or has expired. If this is the case, then the machine is operated in the clockwise direction, the result is the left output to the box 50. If this is not the case, because for example long-term reverse operation is set and the timer has not been actuated or because continuous rotation has been set and the timer has been actuated and has not yet expired, then the right exit to the box 52 results; the machine is operated in reverse.

The electronic controller 26 is preferably program-controlled. It may be, for example, a microprocessor control. The decision logic according to Fig. 2 is periodically polled by the electronic controller 26 approximately every 1 to 10 milliseconds.

Claims (15)

1. A machine for screwing or drilling having a motor (12) for driving a drive shaft (14), a controller (26) for controlling the machine (10), a motor switch (SWSTART) for switching the motor (12) on and off, switching means (SWRL) for reversing the machine between clockwise and counter-clockwise rotation, and vice versa, characterized in that a timer (TLL) is provided that permits reversal of the machine between clockwise/counter-clockwise rotation, and vice versa, only within a predefined period of time between actuation of the switching means for clockwise/counter-clockwise rotation and operation of the motor switch (SWSTART) to start the machine (20).
2. The machine of claim 1, characterized by switching means (SWRL) for reversing the machine between permanent clockwise/permanent counter-clockwise rotation, and vice versa, and comprising storage means for storing the permanent clockwise or permanent counter-clockwise operating state.
3. The machine of claim 2, characterized in that the controller (26) is configured such that the machine (10) will reset to permanent clockwise rotation every time the machine (10) is decoupled from voltage supply.
4. The machine of any of the preceding claims, characterized in that the switching means comprise first switching means for reversing a stored permanent clockwise rotation (!DLL) or permanent counter-clockwise rotation (DLL) state to the respective opposite direction of rotation for a single start of the machine (10).
5. The machine of any of the preceding claims, characterized in that the switching means comprise a first switch (SWLIGHT) and a second switch (SWRL) which, when operated successively, allow the machine to be reversed between permanent clockwise and permanent counter-clockwise operation, and vice versa.
6. The machine of claim 5, characterized in that the first switch is designed as light switch (SWLIGHT) that allows additional activation of a lighting system (29).
7. The machine of claim 5 or claim 6, characterized in that the second switch is designed as clockwise/counter-clockwise rotation changeover switch (SWRL).
8. The machine of claim 6 or 7, characterized in that the light switch (SWLIGHT) is coupled with the motor switch (SWSTART) in such a way that in a first switching stage only the light switch (SWLIGHT) is operated while in a second switching stage the light switch (SWLIGHT) and the motor switch (SWSTART) are actuated simultaneously.
9. A method of controlling the direction of rotation of a machine for screwing or drilling, comprising the following steps:

   (A) setting the direction of rotation to clockwise or counter-clockwise;

   (B) monitoring whether a switching means for reversing the direction of rotation is activated;
   characterized in that the additional steps follow:

   (C) starting a timer, if an activation of the switching means is sensed;

   (D) monitoring, whether a motor switch is activated to start the motor, before a preset time period beginning with the starting of the timer has elapsed;

   (E) if the motor switch is activated within the preset time period, reversing the direction of rotation of step (A) and starting the motor with the reversed direction of rotation; and

   (F) starting the motor with the direction of rotation preset in step (A), if the motor switch is activated after the preset time period has elapsed.
10. The method of claim 9, characterized in that a permanent direction of rotation is saved.
11. The method of claim 10, characterized in that the permanent direction of rotation is reset to a predefined state, preferably to permanent clockwise direction of rotation, when the machine is started the first time or when the machine is cut off from power supply.
12. The method of claim 10 or 11, characterized in that the permanent direction of rotation is reversed and saved when a certain switching means is activated.
13. The method of any of claims 10 to 12, further characterized by the following steps:

    (G) operating the machine with the saved permanent direction of rotation, if the motor switch is activated without activating the switching means for reversing the direction of rotation or when the motor switch is only activated after the preset time period of the timer has elapsed; and

    (H) operating the machine one time with a direction of rotation opposite to the saved permanent direction of rotation, if according to step (5), after having activated the switching means for reversing the direction of rotation, the motor switch is activated before the preset time period of the timer has elapsed.
14. The method of any of claims 9 to 13, characterized in that the preset time period is 30 seconds at the most, preferably 15 seconds at the most, particularly preferred 5 seconds at the most.
15. The method of any of claims 9 to 14, characterized in that a counter-clockwise operation of the machine is indicated to a user using indicator means (28).

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