EP2271553B1 - Mobile strapping device - Google Patents

Description

The invention relates to a mobile strapping device for strapping of packaged goods with a strapping, which comprises a tensioning device for applying a belt tension on a loop of a strapping band, and a friction welding device for generating a Reibschweissverbindung on two superimposed areas of the loop of the strapping, and a rechargeable energy storage for storage of energy, in particular of electrical, mechanical, elastic or potential energy, which can be released as drive energy at least for the friction-welding device for generating a friction-welded connection.

Such strapping devices (known, for example, from US 4,313,779 A or EP 1 413 519 A1 ) have a tensioning device with which a sufficiently large belt tension can be applied to a belt loop placed around the respective packaged goods. By means of preferably a clamping device of the strapping device, the belt loop for the subsequent connection process can then be fixed to the packaged goods. The connection process is carried out in generic strapping devices by means of a friction-welding device. In this case, the belt loop is pressed onto the belt with an oscillatingly moving friction shoe in the region of two ends. The pressure and the heat generated by the movement melts the usually plastic-containing band locally for a short time. This creates between the two band layers a permanent and at most with great force again to be solved connection between the two band layers.

Generic strapping devices are provided for mobile use, in which the devices carried by a user to the respective site and should not rely on the use of externally supplied supply energy. The energy required for the intended use of such strapping devices for tensioning a strapping band around any packaged goods and for producing a closure is generally provided by previously known strapping devices by an electric accumulator or by compressed air. With this energy is introduced by means of the tensioning device on the tape Tape tension and a closure produced on the strap. Generic strapping devices are also intended to connect only weldable plastic straps together.

In mobile devices, a light weight is of particular importance in order to physically burden the users of the strapping device as little as possible when using the device. Likewise, for ergonomic reasons, the weight of the entire strapping device should be as uniform as possible, in particular in order to avoid concentration of the weight in the head region of the strapping device. Such a concentration leads to unfavorable handling properties of the device. In addition, a possible ergonomic and user-friendly handling of the strapping device is always sought. In particular, the possibility of operating errors and malfunctions should be as low as possible.

The invention is therefore based on the object in a strapping device of the type mentioned to improve the handling and handling properties of the strapping device.

This object is achieved in a generic mobile strapping device according to the invention by a common drive for the clamping device for generating a clamping movement, and for the friction welding device for generating an oscillating Reibschweissbewegung and for a transfer device for generating a transfer movement of the friction-welding device from a rest position to a welding position.

According to the invention, therefore, a mobile strapping device with a motor-driven tensioning device and friction-welding device is provided. In order to be able to use such a strapping device at least approximately as hand-guided strapping machines, it additionally has a likewise motor-driven transfer device of the friction-welding device. In spite of the high degree of automation of the strapping device according to the invention, in terms of the lowest possible weight and to avoid a weight concentration in the head region of the device all of these functional units of the strapping device driven with only one common drive.

This only one drive can preferably be designed as an electric motor, with the drive movement successively the clamping device and the friction welding device can be driven. In an expedient embodiment of the invention, this means are provided with which either an operative connection between the only one drive and the tensioning device or between the drive and the Reibschweißeinrichtung can be generated, for example by reversing the direction of rotation of a motor shaft of the drive.

With this only one motor not only the drive movement of the welding process itself but also a movement of the friction welding device is generated from a rest position to a welding position. In the welding position, a welding element of the friction-welding device bears on the band layers to be welded together with pressure and generates a friction-welded connection by means of an oscillating movement on the band layers. In this case, the welding element of the friction-welding device in the rest position is preferably inactive and is preferably set in motion only at the beginning of a movement out of the rest position.

The drive of the portable mobile strapping device may preferably be a single electric motor. It has been found that the motor can be advantageously designed as a brushless DC motor. Such an engine may be operated in a manner in which it outputs a substantially constant torque at different speeds.

With the use of a brushless DC motor as drive for the clamping device, further advantages can be achieved. As a result, it is possible to control the clamping operation speed dependent. This allows, for example, even at low speeds a - compared to previously possible torques - to provide comparatively high torque of the clamping device. Thus, with such mobile strapping devices, for example, for the first time a band at low speed but towards the end of Nevertheless, clamping process with a high clamping force to put packaged goods. In previous clamping devices to achieve a sufficient belt tension, the band had to be moved at the beginning of the tensioning process at high speed, so that towards the end of the clamping process in the band, the desired belt tension can be achieved. The tape is thereby whipped properly against the packaged goods, which involves a high risk of damage to the packaged goods in itself. This also sensitive packaged goods, now with significantly lower risk of damage with a band with high band tension can be strapped.

Furthermore, a speed-dependent tensioning operation also enables a quick first tensioning, i. a tensioning at a high belt retraction speed, followed by a second tensioning operation with reduced belt retraction speed compared to the first tensioning operation. The belt retraction speeds can be adjusted in particular in such brushless motors due to the possibility of adjusting the speed of the motor shaft and the engine torque in certain areas independently, adjust the required or desired conditions in both clamping operations. With the described division into a first and at least a second clamping operation, particularly high belt tensions can be achieved.

Advantageously, at least one planetary gear is arranged in the power flow between the common drive for the friction welding device and for the clamping device. With this can be, among other things, with respect to the weight of the strapping device and their weight distribution, a particularly favorable way to provide the usually significantly different required speeds for the clamping device and the Reibschweißeinrichtung produce.

The degree of automation of the strapping device according to the invention can advantageously be further improved with the smallest possible number of components required for this purpose, so that the coordination between the transfer device and the friction-welding device also takes place by means of the same only one drive. It can therefore be provided that the drive movement of the motor both as a drive source of the automatic transfer device as is also used to achieve an at least approximately synchronous beginning of the oscillating movement of the Reibschweisselements and the transfer movement of the transfer device. For this purpose, a transmission device can be provided which transforms the motor drive movement into different sub or gear ratios and emits them at two different points, preferably at the same time, namely at one point for the friction-welding device and at another point for the transfer device

The common transmission device of the friction-welding device and its transfer device can be advantageously arranged on a freewheel, which passes on the drive movement to the transmission device only in a certain direction of rotation of a drive shaft of the motor. This is preferably a different direction of rotation than the direction of rotation with which the tensioning device is driven. It has thus proved to be advantageous if - seen in the direction of passing the drive movement - only behind the freewheel, a splitting of the drive movement takes place on the one hand in the direction of Reibschweisselement the friction-welding device and on the other hand to the transfer device. For this purpose, the transmission device can have a first gear part for the friction-welding device and a second gear part for the transfer device, wherein the two gear parts carry out different sub-or translations of the drive movement.

It has proven to be particularly advantageous if in the drive train of the transfer device as part of the transmission device, a transmission is provided with which a reduction ratio in a range of 100: 1 to 30: 1, preferably 40: 1 to 80: 1 and particularly preferably from 50: 1 to 70: 1 is achievable. Such a reduction ratio can be achieved with advantage in particular by a planetary gear, in particular a multi-stage planetary gear. But other types of transmission can be provided for this purpose, for example bevel gear.

An expedient embodiment of the provided with a planetary gear preferred embodiment of the invention may comprise a cam control, with a rotating cam for on and preferably also to turn off the Friction welding device is used. It can be provided that the cam causes a movement of the friction-welding device from a rest position to a welding position by mechanical actuation.

Self-importance may also have an embodiment of the strapping device, in which an actuating means is provided for the common actuation of the tensioning device and the friction-welding device, by which the tensioning device and the friction-welding device are successively put into operation. In this case, it is preferred if, in the case of the strapping device, either the tensioning device and the friction-welding device can be triggered jointly by only one actuation of the actuating means for the successive execution of their functions or if the tensioning device and the friction-welding device can be actuated separately from one another. In the common triggering so by a common trigger manipulation, for example, by pressing only one switch, the clamping device is first set in motion and automatically after the completion of the clamping operation and without further manual manipulation of the device, the welding process started and carried out. In the separate operation, however, the user can determine the times when the tensioning device is used and at which time interval is set by a separate operation, the friction-welding device independently of the tensioning device in motion. For this purpose, it is provided that a separate actuation of an actuating element is provided for triggering the Reibschweissvorgangs, which then run a likewise at least largely automated expiring welding process.

In one possible development of the invention, an adjustable and actuatable switching means can be provided for realizing these two modes, with which the actuating means with the common triggering function or with the possibility of independent and separate operation of the clamping device and friction welding device can be assigned.

Further preferred embodiments of the invention will become apparent from the claims, the description and the drawings.

Fig. 1

eine perspektivische Darstellung einer erfindungsgemässen Umreifungs vorrichtung;

Fig. 2

das Umreifungsgerät aus Fig. 1 ohne Gehäuse;

Fig. 3

eine teilweise geschnittene Darstellung des Motors der Umreifungsvorrichtung aus Fig. 1 zusammen mit auf der Motorwelle angeordneten Komponenten;

Fig. 4

eine stark schematisierte Darstellung des Motors zusammen mit seiner elektronischen Schaltung zur Kommutierung;

Fig.5

eine perspektivische Teildarstellung des Antriebsstrangs des Umreifungsgeräts aus Fig. 1;

Fig. 6

der Antriebsstrang aus Fig. 5 in einer Darstellung aus einer anderen Blickrichtung;

Fig.7

eine Seitenansicht des Antriebsstrangs aus Fig. 5 mit der Schweißeinrichtung in einer Ruheposition;

Fig.8

eine Seitenansicht des Antriebsstrangs aus Fig. 5 mit der Schweißeinrichtung in einer Position zwischen zwei Endpositionen;

Fig.9

eine Seitenansicht des Antriebsstrangs aus Fig. 5 mit der Schweißeinrichtung in einer Schweissposition.

Fig. 10

eine Seitenansicht auf die Spanneinrichtung des Umreifungsgerätes ohne Gehäuse, in der sich eine Spannwippe in einer Ruhestellung befindet;

Fig. 11

eine Seitenansicht auf die Spanneinrichtung des Umreifungsgerätes ohne Gehäuse, in der sich eine Spannwippe in einer Spannstellung befindet;

Fig. 12

die teilweise geschnitten dargestellte Spannwippe des Umreifungsgerätes aus Fig. 10 in einer Seitenansicht;

Fig. 13

die Spannwippe aus Fig. 12 in einer Frontansicht;

Fig. 14

ein Detail aus Fig. 12 gemäss der Linie C - C.

The invention will be explained in more detail with reference to embodiments shown purely schematically in the figures, in which:

Fig. 1

a perspective view of an inventive strapping device;

Fig. 2

the strapping device off Fig. 1 without housing;

Fig. 3

a partially sectioned view of the motor of the strapping from Fig. 1 together with components arranged on the motor shaft;

Fig. 4

a highly schematic representation of the engine together with its electronic circuit for commutation;

Figure 5

a partial perspective view of the drive train of the strapping device Fig. 1 ;

Fig. 6

the powertrain off Fig. 5 in a representation from another perspective;

Figure 7

a side view of the drive train Fig. 5 with the welding device in a rest position;

Figure 8

a side view of the drive train Fig. 5 with the welding device in a position between two end positions;

Figure 9

a side view of the drive train Fig. 5 with the welding device in a welding position.

Fig. 10

a side view of the clamping device of the strapping device without housing, in which a clamping rocker is in a rest position;

Fig. 11

a side view of the clamping device of the strapping device without housing, in which a clamping rocker is in a clamping position;

Fig. 12

the partially cut illustrated rocker of the strapping Fig. 10 in a side view;

Fig. 13

the tilting rocker Fig. 12 in a front view;

Fig. 14

a detail from Fig. 12 according to the line C - C.

That in the Fig. 1 and 2 shown, exclusively hand-operated inventive strapping device 1 has a housing 2, which surrounds the mechanism of the strapping device and on which a handle 3 for handling the device is formed. The strapping apparatus is further provided with a base plate 4, the underside of which is provided for placement on an object to be packaged. On the base plate 4 and connected to the base plate not shown carrier of the strapping device all functional units of the strapping device 1 are attached.

With the strapping device 1, a in Fig. 1 not shown loop of a plastic tape, for example, polypropylene (PP) or polyester (PET)), which was previously placed around the object to be packaged, are tensioned by means of a tensioning device 6 of the strapping device. The clamping device has for this purpose a tensioning wheel 7, with which the band can be detected for a clamping operation. The tensioning wheel 7 acts together with a rocker 8, which can be pivoted by means of a rocker arm 9 from an end position with distance to the tensioning wheel in a second end position about a rocker pivot axis 8a, in which the rocker 8 is pressed against the tensioning wheel 7. Also located between the tensioning wheel 7 and the rocker 8 band is in this case pressed against the tensioning wheel 7. By rotation of the tensioning wheel 7, it is then possible to provide the belt loop with a sufficiently high for the packaging purpose tape tension. The process of clamping and this purpose advantageously trained rocker 8 will be explained in more detail below.

Subsequently, a welding of the two layers by means of the friction-welding device 8 of the strapping device can take place at one point of the belt loop on which two layers of the belt lie one above the other. The strap loop can thereby be permanently closed. For this purpose, the friction-welding device 10 is provided with a welding shoe 11, which melts the two layers of the strapping band by mechanical pressure on the strapping band and a simultaneous oscillating movement with a predetermined frequency. The plasticized or molten areas flow into each other and after cooling of the band then creates a connection between the two band layers. If necessary, then the belt loop can be separated from a supply roll of the tape by means of a cutting device of the strapping device 1, not shown.

The actuation of the tensioning device 6, the delivery of the friction-welding device 10 by means of a transfer device 19 (FIG. Fig. 6 ) of the friction-welding device 10 as well as the use of the friction-welding device per se and the operation of the cutting device are carried out using only a common electric motor 14, which provides a drive movement for each of these components. To the power supply, a replaceable and removable in particular for charging accumulator 15 is arranged on the strapping device. A supply of other external auxiliary energy, such as compressed air or other electricity, is in the strapping apparatus according to the Fig. 1 and 2 not provided.

In the present case, the portable mobile strapping device 1 has a trained as a pressure switch actuator 16, which is provided for commissioning of the motor. For the actuating element 16 17 three modes can be adjusted by means of a switch. In the first mode, by operating the actuator 16 without requiring any further operator action, both the tensioner 6 and the friction welder 10 are triggered sequentially and automatically. To set the second mode, the switch 17 is switched to a second switching mode. In the second possible mode then by operating the actuating element 16 only the Clamping device 6 triggered. For separate triggering of the friction-welding device 10, a second actuating element 18 must be actuated by the operator. In alternative embodiments, it may also be provided that in this mode for triggering the friction-welding device, the first actuating element 16 is to be actuated a second time. The third mode is a kind of semiautomatic, in which the tension button 16 is to be pressed until the prestressed tension or tensile stress in the belt is reached. In this mode, it is possible to interrupt the clamping process by releasing the tensioning button 16, for example, to attach edge protectors to the Umreifungsgut under the strapping. By pressing the tension button, the clamping process can then be resumed. This third mode can be combined with a separately triggered as well as with an automatically subsequent friction welding process.

On a in Fig. 3 shown motor shaft 27 designed as a brushless, grooved female rotor DC motor 14, a transmission device 13 is arranged. In the embodiment shown here, a motor of the company. Maxon Motor AG, Brünigstrasse 20, 6072 Sachseln, type EC140 is used. The brushless DC motor 14 can be operated in both directions of rotation, with one direction of rotation being used as the drive movement of the clamping device 6 and the other direction of rotation being used as the drive movement of the welding device 10.

The in Fig. 4 brushless DC motor 14 shown purely schematically is formed with a grooved internal rotor (rotor) 20 with three Hall sensors HS1, HS2, HS3. This EC motor (electronically commutated motor) has a permanent magnet in its rotor 20 and is provided with an electronic control 22 which is provided for electronic commutation in the stator 24. The electronic controller 22 determines via the Hall sensors HS1, HS2, HS3, which also assume the function of position sensors in the embodiment, the respective instantaneous position of the rotor 20 and switches the electric magnetic field in the windings of the stator 24. Thus, the phases (Phase 1, Phase 2, Phase 3) are switched in response to the position of the rotor 20 to cause a rotational movement of the rotor in a certain direction of rotation, with a predeterminable variable speed and torque. In the present case, a so-called "1 quadrant motor drive amplifier" is used, which the motor provides the voltage, as well as peak and continuous current and this regulates. The current flow for not shown coil strands of the stator 24 is controlled by a bridge circuit 25 (MOSFET transistors), ie commutated. Furthermore, a not further shown temperature sensor is provided on the engine. It is thus possible to monitor and control the direction of rotation, the speed of rotation, the current limit and the temperature. The commutation is constructed as a separate print component and accommodated in the strapping device separately from the motor.

The power supply is ensured by the trained as a lithium-ion battery accumulator 15. Such rechargeable batteries are based on a number of independent lithium-ion cells, in each of which at least substantially independently chemical processes for generating a potential difference between two poles of the respective cell take place. In the exemplary embodiment is a lithium-ion battery manufacturer Robert Bosch GmbH, D-70745 Leinfelden-Echterdingen. The battery of the embodiment has eight cells and has a capacity of 2.6 ampere hours. As an active material or as a negative electrode of the lithium-ion battery graphite is provided. The positive electrode of the accumulator often has lithium metal oxides, in particular in the form of layer structures. The electrolyte used is usually anhydrous salts, such as lithium hexafluorophosphate or polymers. The voltage delivered by a conventional lithium-ion battery is usually 3.6 volts. The energy density of such accumulators is about 100 Wh / kg - 120 Wh / kg.

The transmission device 13 has a freewheel 36 arranged on the motor-side drive shaft, on which a sun gear 35 of a first planetary gear stage is arranged. The freewheel 36 is only in one of the two possible directions of rotation of the drive, the rotational movement of the sun gear 35 on. The sun gear 35 meshes with three Planentenrädern 37, which are in a conventional manner in engagement with a fixed ring gear 38. Each of the planet gears 37 is in turn arranged on a respective shaft 39 associated therewith, which is in each case integrally connected to a driven gear 40. The rotation of the planetary gears 37 about the motor shaft 27 results in a rotational movement of the output gear 40 about the motor shaft 27 and determines a rotational speed of this rotational movement of the output gear 40. In addition to the sun gear 35 is located also the output gear 40 on the freewheel 36 and is thus also mounted on the motor shaft. This freewheel 36 causes both the sun gear 35 and the output gear 40 rotate only in one direction of rotation of the rotational movement of the motor shaft 27. The freewheel 29 may for example be of the type INA HFL0615, as offered by the company Schaeffler KG, D-91074 Herzogenaurach.

The gear device 13 has on the motor-side output shaft 27 also a belonging to a second planetary gear toothed sun gear 28, through the recess while the shaft 27 is performed, in this case, the shaft 27 is not connected to the sun gear 28. The sun gear is fixed to a disc 34, which in turn is connected to the planetary gears 37. The rotational movement of the planetary gears 37 about the motor-side output shaft 27 is thus transmitted to the disc 34, which in turn transmits its rotational motion identical to the sun gear 28. The sun gear 28 meshes with a plurality of planetary gears, namely three, each disposed on a parallel to the motor shaft 27 extending shaft 30 gears 31. The shafts 30 of the three gears 31 are arranged stationary, i. they do not rotate about the motor shaft 27. The three gears 31 are in turn with an internally toothed ring gear engaged, which has on its outer side a cam 32 and hereinafter referred to as the cam wheel 33. The sun gear 28, the three gears 31 and the cam 33 are components of the second planetary gear stage. The planetary gear input rotational rotation of the shaft 27 and the rotational movement of the cam wheel 33 are in a ratio of 60: 1, i. through the two-stage planetary gearbox takes place a 60-fold reduction.

At the end of the motor shaft 27, a bevel gear 43 is also arranged on a second freewheel 42, which is in engagement with a second bevel gear, not shown. This freewheel 42 also transmits only in one direction of rotation of the motor shaft 27, the rotational movement. The direction of rotation, in which the freewheel 36 of the sun gear 35 and the freewheel 42 transmit the rotational movement of the motor shaft 27 are opposed to each other. This means that in one direction of rotation rotates only the freewheel 36 and in the other direction only the freewheel 42 with.

The second bevel gear is arranged at one end of a clamping shaft, not shown, which carries at its other end another planetary gear 46 ( Fig. 2 ). The drive movement of the electric motor in a certain direction of rotation is thus transmitted to the two bevel gears 43 to the clamping shaft. By means of a sun gear 47 and three planetary gears 48, the tensioning wheel 49 of the tensioning device 6 designed as an internally toothed ring gear is thereby set in rotation. The provided on its outer surface with a surface structure tensioning wheel 7 takes in its rotational movement, the respective strap through a frictional engagement, whereby the intended belt tension is applied to the belt loop.

The output gear 40 is formed in the region of its outer peripheral surface as a gear on which a toothed belt 50 of an envelope drive is arranged ( Fig. 5 and Fig. 6 ). The toothed belt 50 also wraps around a relative to the output gear 40 in diameter smaller pinion 51, whose shaft drives an eccentric 52 for an oscillating reciprocating movement of the welding shoe 53. Instead of a toothed belt drive and any other form of enveloping drives could be provided, such as a V-belt or chain drive. The eccentric drive 52 has an eccentric shaft 54, on which an eccentric 55 is arranged, on which in turn sits a welding shoe arm 56 with a circular recess. The eccentric rotational movement of the eccentric 55 about the axis of rotation 57 of the eccentric shaft 54 leads to a translational oscillating reciprocating motion of the welding shoe 53. Both the eccentric 52 and the welding shoe 53 itself can also be formed in any other manner known per se.

The welding device is further provided with a toggle device 60, by means of which the welding device is moved from a rest position (FIG. Fig. 7 ) in a welding position ( Fig. 9 ) can be transferred. The toggle device 60 is attached to the welding shoe arm 56 and in this case provided with a pivotable on Schweissschuharm 56 longer toggle lever 61. The toggle device 60 is further provided with a pivotable about a pivot axis 62 pivoted pivot member 63 which acts in the toggle lever 60 as a shorter toggle. The pivot axis 62 of the pivot member 63 in this case runs parallel to the axes of the motor shaft 27 and the eccentric shaft 57th

The pivotal movement is initiated by means of the cam 32 of the cam wheel 33, which in the counterclockwise rotation in the rotation - based on the representations of Fig. 7 to 9 - the cam wheel 33 passes under the pivot member 63 ( Fig. 8 ). A ramp-like rising surface 32a of the cam 32 in this case touches an inserted into the pivot member 63 contact element 64. The pivot member 63 is thereby rotated clockwise about its pivot axis 62. In the area of a concave recess of the pivoting element 63, a two-part longitudinally adjustable toggle lever rod of the toggle lever 61, which is in two parts according to the principle "piston-cylinder", is arranged pivotable about a pivot axis 69. The latter is also rotatably articulated to a pivot axis 65 designed as a further pivot point 65 of the welding shoe arm 56 in the vicinity of the welding shoe 53 and at a distance from the pivot axis 57 of the welding shoe arm 56. Between the two ends of the longitudinally variable toggle rod, a compression spring 67 is arranged on this, by means of which the toggle lever 61 is pressed both against the welding shoe arm 56 and against the pivoting element 63. The pivoting member 63 is thus operatively connected with the toggle lever 61 and the welding shoe arm 56 with respect to its pivotal movements.

As in the representations of FIGS. 7 and 9 can be seen, is located in the rest position extending through the toggle lever 61 (imaginary) connecting line 68 of the two articulation points of the toggle lever 61 between the pivot axis 62 of the pivot member 63 and the cam wheel 33, ie on one side of the pivot axis 62. By pressing the Cam 33 is the pivot member 63 - with respect to the representations of Fig. 7 to 9 - Turned clockwise. Here, the toggle lever 61 is taken from the pivot member 63 with. In Fig. 8 an intermediate position of the toggle lever 61 is shown, in which the connecting line 68 of the articulation points 65, 69, the pivot axis 62 of the pivot member 63 intersects. In the in Fig. 9 The knee lever 61 is then with its connecting line 68 with respect to the cam wheel 33 and the rest position on the other side of the pivot axis 62 of the pivot member 63. In this movement, the Schweißschuharm 56 by the toggle lever 61 of his Rest position transferred by rotation about the pivot axis 57 in the welding position. In the latter, the compression spring 67 presses the Swivel element 63 against a stop, not shown, and the welding shoe 53 on the two tape layers to be welded together. The toggle lever 61 and thus also the welding shoe arm 56 is thus in a stable welding position.

The in the representation of Fig. 6 and 9 counterclockwise driving movement of the electric motor is transmitted from the timing belt 50 to the now transferred by the toggle lever 60 in the welding position welding shoe 53, which is pressed on the two band layers and moves back and forth in an oscillating motion. The welding time for generating a Reibschweissverbindung is determined by the fact that the adjustable number of revolutions of the cam wheel 33 is counted from the time from which the cam 32, the contact element 64 is actuated. For this purpose, the number of revolutions of the shaft 27 of the brushless DC motor 14 is counted to determine the position of the cam wheel 33, from which the engine 14 is turned off and thus the welding process is to be terminated. In this case, it should be avoided that when stopping the engine 14, the cam 32 stops below the contact element 64. For stopping the motor 14, therefore, only relative positions of the cam 32 relative to the pivot member 63 are provided, in which the cam 32 is not below the pivot member. This ensures that the welding shoe arm 56 is returned from the welding position to the rest position (FIG. Fig. 7 ) can pivot. In this way, in particular a position of the cam 32 is avoided, in which the cam 32 would arrange the toggle lever 61 in a dead center position, ie in a position in which the connecting line 68 of the two articulation points, the pivot axis 62 of the pivoting element 63 - Fig. 8 shown - cuts. Since such a position is avoided, now by means of an actuation of the rocker lever, the rocker ( Fig. 2 ) Loosened from the tensioning wheel 7 and in this case also the toggle lever 61 in the direction of the cam wheel 33 in the in Fig. 7 be pivoted position shown. After the strap loop is removed from the strapping, the latter is ready for another strapping process.

The described successive processes "clamping" and "welding" can be triggered jointly in a switching state of the actuating element 16. For this purpose, the actuating element 16 is closed once actuate, whereby the electric motor 14 first runs in the first direction of rotation and in this case (only) the tensioning device 6 is driven. The band tension to be applied to the respective band can preferably be set on the strapping apparatus by means of a pushbutton in nine stages which correspond to nine different band tension values. Alternatively, a continuous adjustment of the belt tension could be provided. Since the motor current from the torque of the tensioning wheel 7 and this in turn depends on the instantaneous belt tension, the applied belt tension can be adjusted in the form of a limit of the motor current via push buttons in nine stages on the control electronics of the strapping device.

After reaching an adjustable and thus predeterminable limit value for the motor current or for the belt tension, the motor 14 is turned off by its controller 22. Immediately thereafter, the motor is operated by the controller 22 in the reverse direction of rotation. As a result, in the manner described above, the welding shoe 53 is lowered onto the two superposed belt layers and the oscillating movement of the welding shoe is carried out to produce the friction-welded connection.

By operating the switch 17, the actuator 16 can be occupied only with the function of triggering the clamping device. If such a setting is made, only the clamping device is put into operation by pressing the actuator and turned off again after reaching the preset belt tension. In order to trigger the Reibschweissvorgang the second actuator 18 must be actuated. However, apart from the separate triggering, the function of the friction welding device is identical to the other mode of the first actuating element.

As already explained above, the rocker 8 by pressing the in the Fig. 2 . 10 . 11 illustrated rocker lever 9 pivoting movements to perform about the rocker axis 8a. The rocker is this purpose by means of a behind the tensioning wheel 7 and therefore in Fig. 2 unrecognizable, rotatable cam moves. About the rocker lever 9, the cam can perform a rotational movement of about 30 ° and move the rocker 8 and clamping plate 12 relative to the tensioning wheel 7, which is a Insertion of the tape in the strapping device or between the tensioning wheel 7 and clamping plate 12 allows.

In this way, the arranged in the region of the free end of the rocker on the latter toothed clamping plate 12 of a in Fig. 10 shown rest position in one Fig. 11 resulting clamping position and be pivoted back again. In the rest position, the clamping plate 12 has a sufficiently large distance to the tensioning wheel 7, so that a strapping between the tensioning wheel and the clamping plate can be arranged in two layers, as is required for the formation of a closure on a belt loop. In the clamping position, the clamping plate 12 is pressed in a conventional manner, for example by means of a force acting on the rocker spring force against the tensioning wheel 7, wherein different than in Fig. 11 represented, in a strapping process, the two-ply tape between the clamping plate and the tensioning wheel and thus should take place between the two latter no contact. The tensioning wheel 7 facing toothed surface 12a (clamping surface) is concavely curved, wherein the radius of curvature corresponds to the radius of the tensioning wheel 7, or is slightly larger.

As in particular in the Fig. 10 and 11 as well as in the detailed representations of the Fig. 12 - 14 can be seen, the toothed clamping plate 12 is arranged in a groove-shaped recess 71 of the rocker. In addition, the clamping plate 12 is provided with a convexly curved contact surface 12 b, with which it is mounted in the recess 71 of the rocker 8 on a flat bearing surface 72 is. As can be seen in particular from the Fig. 11 and 12 results, the convex curvature in a direction parallel to the belt running direction 70, while the contact surface 12b formed transversely to this direction ( Fig. 13 ). Due to this configuration, the clamping plate 12 is able to perform in the position in the band running direction 70 relative to the rocker 8 and the tensioning wheel 7 tilting movements. Furthermore, the clamping plate 12 is fastened to the rocker 8 with a screw 73 carried out from below by the rocker. For this purpose, the screw is located in a slot 74 of the rocker, whose longitudinal extent runs parallel to the band path 70 in the strapping device. The clamping plate 12 is thereby in addition to the Verkippbarkeit additionally arranged longitudinally displaceable on the rocker 8.

In a clamping operation, first, the clamping rocker 8 from the rest position ( Fig. 10 ) in the clamping position ( Fig. 11 ). In the clamping position, the spring-loaded rocker 8 presses the clamping plate 12 in the direction of the tensioning wheel and clamps both tape layers between the tensioning wheel 7 and the clamping plate 12. Due to different strip thicknesses, different distances between the clamping plate 12 and the circumferential surface 7a of the tensioning wheel 7 can result. This not only different pivoting positions of the rocker 8 result, but also different position of the clamping plate 12 with respect to the circumferential direction of the tensioning wheel 7. To still achieve uniform contact pressure, the clamping plate 12 is directed during the pressing of the tape by a longitudinal movement in the recess 71 and a tilting movement on the contact surface 12b on the support surface 72 independently so that the clamping plate 12 exerts over its entire length as uniform as possible pressure on the strapping. Now, if the tensioning wheel 7 is turned on, the teeth of the clamping plate 12 holds the lower band position, while the tensioning wheel 7 detects the upper band position with its toothed peripheral surface 7a. The rotational movement of the tensioning wheel 7 and the lower coefficient of friction between the two belt layers then causes the tensioning wheel to retract the upper belt ply and thus increase the tension in the belt loop to the desired tension value.

LIST OF REFERENCE NUMBERS

1

Strapping device 1

2

casing

3

Handle

4

baseplate

6

tensioning device

7

tensioning wheel

7a

peripheral surface

8th

seesaw

8a

Rocker pivot axis

9

rocker lever

10

friction welder

11

welding shoe

12

chipboard

12a

clamping surface

12b

contact area

13

transmission device

14

electric DC motor

15

accumulator

16

actuator

17

switch

18

actuator

19

Transfer device

20

rotor

HS1

Hall sensor

HS2

Hall sensor

HS3

Hall sensor

22

electronic control

24

stator

25

bridge circuit

27

motor-side output shaft

28

sun

30

wave

31

gear

32

cam

32a

area

33

cam

35

sun

36

freewheel

37

planet

38

ring gear

39

wave

40

output gear

42

freewheel

43

bevel gear

46

planetary gear

47

sun

48

planet

49

tensioning wheel

50

toothed belt

51

pinion

52

eccentric

53

welding shoe

54

eccentric shaft

55

eccentric

56

Welding shoe arm

57

Rotation axis eccentric shaft

60

Toggle lever device

61

longer toggle

62

swivel axis

63

pivoting element

64

contact element

65

swivel axis

66

swivel axis

67

compression spring

68

connecting line

69

swivel axis

70

Band-running direction

71

recess

72

bearing surface

73

screw

74

Long hole

Claims (15)

1. Mobile strapping apparatus (1) for strapping packed or packaged goods with a strapping band and having
   a tensioning device (6) for applying tensioning to a loop of a strapping band, and
   a friction-welding device (10) for producing a friction-welding connection at two regions of the loop of the strapping band that are located one above the other, and
   a rechargeable energy store (15) for storing energy, in particular electrical, mechanical, elastic or potential energy, which is releasable as drive energy at least for the friction-welding device for producing a friction-welding connection,
   characterized
   by a common drive for the tensioning device (6) for producing a tensioning movement, and also for the friction-welding device (10) for producing an oscillating friction-welding movement and for a transferring device (19) for producing a transferring movement of the friction-welding device (10) from a rest position into a welding position.
2. Strapping apparatus according to Claim 1, characterized by a drive shaft of the only one drive, said drive shaft being operatively connectable to the tensioning device (6), the friction-welding device (10) and the transferring device (19).
3. Strapping apparatus according to either of the preceding claims, characterized by means by way of which either an operative connection between the only one drive and the tensioning device (6) or between the drive and the friction-welding device (10) and with the transferring device (19) is producible.
4. Strapping apparatus according to at least one of the preceding claims, characterized in that with different directions of rotation of the drive, operative Connections to different functional units of the strapping apparatus are producible and removable, in particular to the functional units of tensioning device (6) and friction-welding device (10).
5. Strapping apparatus according to at least one of the preceding claims, characterized by means by way of which the friction-welding device (10) and the transferring device (19) are drivable with the same direction of rotation of the drive.
6. Strapping apparatus according to at least one of the preceding claims, characterized by a freewheel (36) which is operatively connectable to the drive only in the case of a direction of rotation of the drive for transferring the drive movement, wherein with this direction of rotation the friction-welding device (10) and the transferring device (19) are operatively connectable to the freewheel.
7. Strapping apparatus according to at least one of Claims 4 to 6, characterized in that at least one planetary gear mechanism (46) for changing the speed of a drive movement provided by the electric drive of the friction-welding device (10) is arranged in the flux of force between the drive for the friction-welding device (10) and/or for the tensioning device (6).
8. Strapping apparatus according to at least one of the preceding claims, characterized in that in the flux of force between the drive and a functional unit that is operatively connectable to the drive there is arranged a gear mechanism by way of which a reduction gear ratio in the range of 30:1 to 100:1, preferably of 40:1 to 80:1 and particularly preferably of 50:1 to 70:1 is achievable for the drive movement.
9. Strapping apparatus according to at least one of the preceding claims, characterized by an actuating means for jointly actuating the tensioning device (6) and the friction-welding device (10), as a result of which the tensioning device and the friction-welding device are settable successively into operation.
10. Strapping apparatus according to Claim 9, characterized by a switching means having at least two switching states, wherein in the one switching state thereof the tensioning device and the friction-welding device are actuable jointly and in the second switching state thereof the tensioning device and the friction-welding device are actuable separately from one another.
11. Strapping apparatus according to Claim 10, characterized in that the function of the actuating means is changeable, in particular the two switching states of the switching means are transmittable to the actuating means, by way of the switching means.
12. Strapping apparatus according to at least one of the preceding claims, characterized by a brushless DC motor (14) as common drive.
13. Strapping apparatus according to at least one of the preceding claims, characterized in that the friction-welding device (10) is provided with a toggle lever (60) which is pivotable between two end positions, wherein one end position of the toggle lever determines a friction-welding position and the other end position determines a rest position in which the friction-welding device is not in use.
14. Strapping apparatus according to Claim 13, characterized by a planetary gear mechanism which, for a movement of the toggle lever from its rest position into the friction-welding position, transmits a drive movement of the electric drive to the tensioning device.
15. Strapping apparatus according to at least one of the preceding claims, characterized by a speed-controlled tensioning cycle of the tensioning device, during which the electric drive is operated at least periodically at different speeds with an at least substantially constant torque.

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